Skip to main content

Removal and recovery of nutrients and value-added products from wastewater: technological options and practical perspective

Abstract

Wastewaters from various process industries, namely food and agricultural, sugar mill, brewery, milk, vegetable and fruit, and meat and fisheries processing industries and their wastewater effluents contain nutrients, organic matter, inorganic, heavy metals, suspended solids, and pathogens. The discharges of non-treated wastewater enter the nearby aquatic ecosystem (e.g., lakes, rivers) and are a significant concern due to the presence of different nutrients, competing ions and C containing pollutants. It causes excessive growth of algae, loss of habitat/species, and other negative impacts on human health/environment. In the present review, different treatment approaches have been discussed in utilizing these nutrients to synthesize value-added products such as biopolymer, biofuel, pigment, organic acid, or enzymes. These biopolymers can be used to prepare various food products/packaging materials. Dextran, chitosan, carrageenan, alginate, and pectin are good examples of non-food biopolymers. Besides these products, poly-β-hydroxybutyrate (PHB) synthesis from wastewater nutrients is reported as a new source of bio-nanocomposite materials/biopolymer-based coatings. In this review, the different treatment approaches are discussed, which are being used worldwide for the removal/recovery of nutrients, toxic pollutants, and the potential resource recovery of value-added products from wastewater.

Graphic abstract

Introduction

Process industries dispose of their solid, liquid wastes or byproducts to nearby water bodies directly or indirectly, inducing conditions that harm the water quality and the health of aquatic organisms. This wastewater contains inorganic and organic pollutants and pathogenic microbial species that trigger waterborne diseases or infections to humans and other life forms [1]. Other pathways of water contamination are reported from a landfill produces leachates that can also percolate the soil layer and contaminate the ground water. On the other hand, severe rainfall can cause agricultural and stormwater runoff that carries more nutrients [nitrogen (N), phosphorus (P), and potassium (K)] from the washed-off fertilizers and decomposing organic wastes [2]. Thus, the groundwater and surface water that serves as the drinking water source can also be contaminated. Although industrial wastewater lacks nutrients, it is often rich in organic pollutants and contains numerous toxic chemicals [1, 2]. Different categories of treatment systems (physical, chemical, and biological) have shown their capacity for the purification of contaminated water and can minimize the risks of negatively affecting the waterways.

Biological nutrient removal (BNR) processes and several other technologies are applied to treat domestic sewage and industrial wastewaters. They have reported to achieve high quality of treated effluent, Fig. 1 [3]. However, from a resource recovery viewpoint, N, P, or K are valuable nutrients. Due to technological advancements, they can be recovered and used in agricultural lands for enhancing crop productivity. Furthermore, some challenges have been reported during industrial wastewater treatment. It contains high chemical oxygen demand (COD) and other nutrients (e.g., effluents from slaughterhouses, olive mills, and the textile industry). In such cases, instead of using the conventional activated sludge process, a sequencing batch reactor (SBR) is used wherein different biological treatment steps are performed in time-sequenced stages of operation (fill, react, settle and decant) [3, 4].

Fig. 1
figure1

Different sources of wastewater and the application of various wastewater treatment strategies for water reuse and nutrient recovery

Biopolymers can also be recovered as a resource during the biological treatment of wastewater. The non-food forms of biopolymers are bioplastics which are often used in the food packaging industry. Biopolymers are used in the food industry because of their physicochemical and functional properties. Typical examples include starch, cellulose, chitin, whey, collagen, soy, and casein. Biopolymers have good biodegradability and mechanical stability. Therefore, they are used to increase the texture of food gel and freeze fruit juices or pulps [5, 6]. There are specific steps involved in producing biopolymers and new challenges for their implementation in the food industry. In recent years, scientists have been researching on the production of healthy biopolymer-based foods to meet the consumers’ expectations and market demands. The application of biopolymers is currently limited in different fields due to their hydrophilic characteristics, high water vapor, and gas permeability [6].

The most commonly known food-grade biopolymers are dextran, chitosan, alginate, or pectin. Previous studies have shown poor interaction between the cationic ε-polylysine or neutral biopolymers. Still, strong interaction between the cationic ε-polylysine and anionic biopolymers are found. Mainly, it depends on the biopolymer type and mass ratio to ε-polylysine [7]. The cationic ε-polylysine (ε-PL) has food-grade antimicrobial properties, and it prevents the action of food pathogens or food spoilage causing microorganisms. It has been reported that cationic ε-polylysine has an interactive nature and can be found in a variety of food-grade biopolymers. Pectin, alginate, or (carrageenan) and neutral (dextran) or cationic (chitosan) biopolymers are the main products [8]. This type of interaction is confirmed by carrying out isothermal titration and calorimetry (ITC). Micro-electrophoresis (ME) or turbidity measurement studies have also been reported in the literature [7, 8]. Considering the background mentioned above and the literatures on this topic, this review mainly focuses on identifying the role of nutrients, applying microbial processes to convert nutrients to useful products, and the recovery of biopolymers from wastewater.

Recently, the polyhydroxyalkanoate (PHA) extraction approach has been discussed wherein the municipal secondary wastewater sludge has been used as a primary raw material and the extraction performance/yield has been improved via optimizing the process conditions. These parameters were temperature, duration time and the solid sludge concentration. Optimal parameters in the extraction process showed good results of recovered PHA (0.65 g) compared to the non-optimized conditions. A further task was on PHA characterization via GC–MS and FTIR analytical techniques [8]. Also, NMR spectroscopy finds application in the PHA characterization task. These techniques reveal information on the PHA profile and it was shown to contain 58% medium chain length (MCL) PHAs. Hence, the extracted PHA with rich, diverse nature from municipal secondary waste sludge (as raw material) can be utilized at a minimal cost. It explores the potential of waste for biopolymers with reduced cost of its production [9]. This approach finds a sustainable manner for waste management and utility of municipal secondary waste sludge. A few reports also discuss the application of response surface methodology for optimal extraction of PHA recovery with a high yield (0.61 g) [8, 9]. In another report on wastewater utility, the possibility of biodiesel production was demonstrated via the utilization of a dried sewage sludge system. Another study reported enhanced yield (29.8%) with the optimal mode of in situ transesterification conditions [10] and these conditions are temperature (450 °C), catalyst (0.16 g/mL), and sludge solids concentration (5%). The further task was obtaining high purity of biodiesel which was later confirmed via different analytical techniques (GC–MS/FTIR/NMR spectroscopy). The produced biodiesel profiles contained mostly of methyl esters of fatty acid (FAME). These fatty acids are oleic and palmitic with myristic and stearic acid [9]. Others value added products are lauric and palmitoleic acid with linoleic acids, indicating the potential use of sludge as a potential feedstock for biodiesel synthesis. Besides, in these two reports, the analyzed FAME profile also showed high-quality biodiesel from this process [9, 10].

In another study, the Serratia species ISTD04 was discovered to be involved in the carbon dioxide sequestration process through genomic analysis [10]. These microbe isolates are involved in the biosynthesis of exopolysaccharides (EPS) in the context of microbial fermentation. The key and accessory enzymes were identified using this technique of analysis. The report also discusses the genes involved in EPS biosynthesis and the structure of the EPS genome. This research helped in the identification of eight putative genes that are found in clusters and are thought to be involved in the CO2 sequestering process for the production of EPS. Substrates had an impact on EPS biosynthesis titers [10], with glucose having an impact of 0.88 g/L and bicarbonate having an impact of 1.25 g/L. Lipopolysaccharides and stewartan are produced as a result of this microbe's activity. Emulsan and polysaccharides [11] are the other products that can also be produced by fermentation. The capsular polysaccharides and fatty acid synthesis have also been reported by a number of researchers. When the EPS titer was increased by more than threefold, the optimal process parameters for EPS biosynthesis were also reported by the authors [11]. Furthermore, the functional groups and monomer compositions, with a particular emphasis on linkage analysis and purified EPS structures, were delineated in that study. Glucose and galactose sugars have been identified as monomers in EPS. The presence of other sugars such as mannose and glucosamine was also reported. This EPS can be used for bioflocculation (measured by kaolin test at 58% flocculating activity) and for dye removal (measured by crystal violate removal at 95%) applications. In EPS biosynthesis, this bacterial strain can be used in a carbon-sequestering approach that has the potential to be expanded in the future [10, 11].

The amount of waste generated by various processing industries has recently become a critical issue. The biorefineries approach is now being applied for the production of biodiesel using waste materials (i.e., organic and raw carbon) as a potential feedstock. It may provide low- or no-emission alternatives to fossil fuels [11]. The utility of municipal secondary sludge materials as growth media for chemolithotrophic Serratia species is well documented in ESTD 04, and this microbe is a strain of the oleaginous bacteria. Analytical studies were conducted on the hydrocarbons in the C7–C25 length range and fatty acids (saturated and unsaturated) in biodiesels [12]. This composition results in enhanced biofuel production. The optimal in situ transesterification process parameters were mentioned by the authors, resulting in an increased yield by more than 25%. This optimal parameter indicates an increase in the efficiency of the transesterification process (74–94%). Besides, the authors also reported the biodiesel fuel property in terms of the total acidity and cetane number of the fuel. Pour points, a high heating value, and cloud point are also some of the properties that should be considered during evaluation. In general, for biofuel production to be viable at the commercial scale, the properties of biofuel have been determined to be suitable for blending at a rate of 5% using the ASTM standard methods [11, 12].

Numerous researchers have concluded that the excessive use of synthetic plastics has a negative impact on the health of the environment. This also contributes to plastic pollution and its accumulation in water bodies, aquatic ecosystems and natural resources. Plastic pollution can be avoided by utilizing biopolymers that are environmentally friendly and aid in the survival of certain living organisms. The use of biopolymers has a number of advantages due to their biodegradability and biocompatibility. In comparison to other biological systems, certain bacterial species can synthesize and accumulate a large quantity/amount of PHAs (plant cell). Numerous studies have been conducted on the major stumbling block in the context of bacterial PHS biosynthesis, which is the requirement for the fermentation and downstream processing costs [12]. This is the major obstacle in the biosynthesis of bacterial PHAs, and it also necessitates the aforementioned properties and opportunities. Several researchers have discussed the structural diversity of PHAs as well as the mechanisms of bacterial degradation and biosynthesis. Additional research on PHAs usage have also revealed its life-cycle analysis and environmental impacts. In a recent study, several advanced tools and techniques have been discussed and applied in recent years to quantify PHA biosynthesis under the influence of various environmental factors [13]. These factors may have an effect on the commercialization of bioplastic applications and synthesis. PHAs have a variety of extraction techniques, downstream processing steps, and biomedical applications. By considering the future scenarios and environmental sustainability, these biopolymers (PHAs) can present opportunities and challenges for commercial-scale utility. They can contribute to the goal of promoting sustainable natural resource development [12, 13].

Status of wastewater reuse

Nowadays, the reuse of wastewater is practiced worldwide to overcome the persisting problem of water scarcity. The recommended guideline for wastewater reuse is documented in QMRA [14]. Typical wastewater from domestic/household sources includes toilet flushing, laundry, dishwashing, food residues, oils, soaps, and numerous chemicals. Thus, wastewater can be from domestic, industrial, commercial, or agricultural activities, surface runoffs, stormwater, and sewer infiltration [15]. For this reason, efficient and resilient wastewater treatment processes are used to remove BOD, COD, suspended solids, toxic pollutants, and pathogenic microorganisms. In many developing and developed countries wastewater reuse for irrigation purposes has been demonstrated [16]. Nevertheless, wastewater from commercial establishments (e.g., beauty salons, furniture refinishing, automobile washing, and repairing) might contain hazardous/toxic materials. Therefore, this type of wastewater will require additional treatment steps [17].

From an ecosystem viewpoint, the shorelines, beaches, marshy lands, and mangrove forests are natural habitats for hundreds of fish species and other aquatic life forms [18]. Besides, the migratory waterbirds use the area for resting and feeding. Clean water sources are used for scenic and recreational activity, while in some countries, they also serve as residential areas for the citizens. Thus, clean water is essential for the survival of humans, plant, and animal species and for preserving the ecosystem quality [19].

Wastewater from the food and agricultural industries

Wastewater from the food and agro-industries emerges from a variety of processing units, for example, slaughterhouses, coffee processing industry, breweries, pulp and paper industry, biodiesel production, etc. Based on the wastewater composition (i.e., its high COD content), there is a great potential of the waste streams of these industries to support/facilitate nutrient recovery and generate valuable, economical, and sustainable products [20]. A study in Brazil showed three common agro-industrial byproducts. These are cheese whey from the cheese production industry and steep corn liquor from the corn wet milling industry. Vinasse from the sugarcane alcohol industry was treated with mixotrophic cultivation of Chlorella vulgaris to reduce their toxicity and remove the high nutrient concentrations for a safe discharge and generate value-added biomass for industrial applications [21]. A recent paper reviewed the utilization of lignocellulosic agricultural wastes for biogas production. The authors mentioned that agricultural residues' anaerobic digestion (AD) is a reliable alternative energy source, producing biomethane. Such an approach could reduce greenhouse gas emissions (GHGs) in the order of 979 Mt CO2 eq. per year [20, 22].

The agro-industrial wastewater contains high COD, and therefore, it can efficiently serve as a suitable feedstock for microbial fuel cells (MFC). However, the power density (PD) and the coulombic efficiency (CE) will vary depending on the wastewater's type/source, composition, and physico-chemical characteristics. For wastewaters containing easily degradable natural organic matter such as soluble sugars or volatile fatty acids (VFAs), MFCs have shown promising results [23].

High-molecular weight compounds such as celluloses, starches, or proteins can be used as substrates in MFC, but they tend to show low PD and CE than pre-fermented media or glucose. However, the formation of free ammonia and long-chain fatty acids during the biodegradation process and the competition between nitrate and sulfates at the anode can severely inhibit the functioning of the MFC system [24]. The wastewater composition of some agro-industries and their possible nutrient recovery options are discussed in the following sections.

Agriculture processing wastewater

There has been a growing trend in maximizing crop yield to meet the unexpected rise in food demand worldwide. The use of chemical fertilizers and pesticides has majorly helped to fulfil this demand. Subsequently, small- and large-scale farming has made agricultural activities a potential source of environmental pollution [20, 25]. In some countries, farmers have been using direct wastewater due to a lack of freshwater resources. On the other hand, the excess/overuse of fertilizers, pesticides/insecticides, and herbicides has led to agricultural runoff, affecting human health and the environment [26]. According to UNESCO (2017), more than 80% of the generated wastewater is released to the environment or the ecosystem without adequate treatment. However, it is noteworthy to mention that, the wastewater is a rich and abundant water source, energy, nutrients, and other valuable renewables/recoverable products. Although the costs of wastewater management is balanced by minimizing the health risks, it can provide economic and environmental benefits and create new business opportunities that will facilitate a circular economy in the region [27, 28]. Thus, concerning wastewater irrigation, it is reported as a common practice in many parts of the world with severe freshwater scarcity.

On the one hand, such an approach increases the reuse efficiency of the available water resources and can positively impact livelihoods. While, on the other hand, the wastewater can percolate and contaminate the groundwater and surface waters. Hence, the prevailing hydrochemical processes in the region, the soil and groundwater characteristics are analyzed/characterized to ascertain the geochemical and hydrological effects of wastewater irrigation [28]. For example, in the city of Hyderabad in India, the farmers are practicing intensive agricultural activities for the past few decades in the peri-urban areas. Every month, the groundwater in this region is sampled to ensure its quality for drinking and domestic purposes [29, 30]. Some important highlights of this study are summarized as follows:

  1. 1.

    Groundwater samples were collected from three sampling locations (watershed irrigated area, groundwater, and the upstream peri-urban area) and analyzed for anions, cations, and nutrients.

  2. 2.

    The anthropogenic influence in the hydro-geochemical processes (cation exchange, precipitation, or dissociation of minerals using saturated indices) and the freshwater–wastewater aquifer interface was evaluated.

  3. 3.

    The saturation indices of halite, gypsum, and fluorite exhibited mineral dissociation, while calcite and dolomites showed mineral precipitation.

  4. 4.

    The groundwater geochemistry of the watershed sources is controlled by long-term wastewater irrigation. Local rainfall pattern and the water–rock interactions were also reported.

Such results are significant for local decision-makers to develop sustainable groundwater management plans to reduce/minimize aquifer and groundwater pollution due to wastewater irrigation [28, 29, 31].

Brewery processing wastewater

The wastewater generated from the brewery industry contains high quantities of soluble organic materials, nutrients (K and N > 60 mg/L), and suspended solids (SS ~ 300 mg/L), which contributes to an average pollution load of 6000 kg COD/day and 1500 kg SS/day, respectively. The volume of this wastewater usually varies between 2 and 10 m3/m3 of beer produced [32]. Due to its high organic content, different physicochemical and biological wastewater treatment systems are conventionally combined (i.e., integrated/hybrid bioreactors) to remove the pollutants. When the wastewater lacks the required nutrients, external nutrients are added to the wastewater stream to maintain the required COD:N:P ratio (100:5:1) for biological treatment [33]. Recent studies showed the application of electrocoagulation (EC), ultrasonication (US), and sono-electrocoagulation (SEC) processes for the removal of suspended solids present in brewery wastewater. It was reported that the crossflow membrane system can also be integrated into the ED process to obtain high removal of COD at a current density of 100 A/m2, pH of 7.1, and a reaction time of 60 min [34]. Other combined/integrated systems such as the application of nanofiltration and reverse osmosis (RO) combined with SEC have also shown promising results at an operating cost of ~ 1.83$/m3 of wastewater treated [32,33,34].

Meat and poultry processing wastewater

The wastewater generated from slaughterhouses and poultry processing industries can contain high concentrations of organic matter (up to 8000 mg/L), together with high amounts of oil, grease, salt, nitrogen, phosphorus, and suspended solids (~ 500 mg/L). Besides, this type of wastewater also contains many pathogens (Salmonella or Shigella bacteria, helminth eggs, or amoebic cysts). If the industry also uses curing and pickling steps to process the hides, then the chloride concentration can be exceedingly high, i.e., > 75,000 mg/L [35]. The concentration of fats and grease is high due to cooking activities in the plant. Physico-chemical flotation and solubilization ponds are usually employed to treat this type of wastewater, and the sludge formed in the floatation unit is separated using centrifugal decanters [36]. The sludge samples are characterized for different parameters based on proximate analysis or differential thermal analysis. Besides, a boiler combustion test is performed in some sludge samples to ascertain its fuel quality [37].

Fish and shellfish processing wastewater

Wastewater generated from fish and shellfish processing installations contains high organic matter and different pollutants (i.e., oils, protein, suspended solids, P and Cl). The wastewater quality depends on the type of fish processed, and there is always a marked difference in the wastewater characteristics when white or fatty fish species are processed. Thus, there is a wide variation in the organic matter (COD = 2000 mg/L for whitefish and 60,000 mg/L for oily fish species) [38]. In this type of wastewater, microbiological contamination during shellfish harvesting is usually identified by undertaking a sanitary survey. The samples of shellfish are tested for fecal coliforms [39]). The amount of fecal coliform can be elevated during the monsoon periods, and the bacterial concentration in shellfish has shown a strong correlation with other water quality parameters. Therefore, post-harvest treatment is required before marketing the shellfish for human consumption purposes [40].

From a practical viewpoint, in coastal areas, the local economy depends on the fishing and aquaculture industry, accounting for ~ 7% of the income and employment of the citizens. It is important to note that the coastal ecosystem contributes to a substantial native flora and fauna population. The recent interferences due to human activity have damaged the seaside and marine ecosystem [39, 41].

Fruit and vegetable processing wastewater

There are many fruit and vegetable processing industries that generate huge quantities of wastewater during its cleaning activities. Usually, this wastewater has high suspended solids (SS), sugars, or starches; it also contains additional pollutants such as brine or acids. This wastewater contains less amount of aggressive chemicals compared to other sectors. In some cases, fats, oils, and residual pesticides are removed from the fruits and vegetables depending on the products' country of origin [41, 42].

In terms of wastewater treatment, fruit and vegetable processing wastewater can be fermented to produce biohydrogen, which is used for the production of electricity. Fermentation technology also promotes biohydrogen production. It is in the range of 57–70 mL H2/g VS removed at different percolation frequencies. However, the percolation frequency did not affect the overall biohydrogen yield in a dry fermentation reactor. At wastewater dosing frequencies (i.e., the feed) of once or twice every two days have shown ~ 80% biohydrogen production. Besides, biogas production and 97% carbon recovery in the form of biomethane are reported from vegetable market wastes in an anaerobic baffled reactor (ABR) [4344]. In an ABR, the waste is added in the form of a slurry, and effluent recirculation is done to utilize the volatile fatty acids (VFA) formed during the process. In a recent study, COD and VS removals were > 90% in a four-chamber ABR during 30 days of reactor operation [45].

Vegetable oils and fats processing wastewater

During vegetable oils and fats extraction, the amount and quality of wastewater generated depend on the technology applied during its production. Usually, the amount of sewage is reported to be ~ 25 m3 per ton of products, and it contains high COD, BOD, and suspended solids (SS) [46]. The wastewater is also generated from the ethylic transesterification process for biodiesel production without chemical or biochemical catalysts under different thermodynamic conditions. In this process, wet animal fats, soybean, or palm oils are used as the feedstocks for 2 h, at 240 °C, and at pressures varying between 20 and 45 bars for transforming almost all the lipid fraction of the samples to biodiesel [47]. However, the conversion efficiency largely depends on the feedstock, reaction time, operational conditions, and catalysts. Typical conversion efficiencies are 80%, 84%, and 98% for animal fat, soybean oil, and palm oil, respectively [46, 47]. This process is thermodynamically favorable compared to the traditional esterification or transesterification processes. The discharge of fats, oils, and grease (FOG) containing wastewater affects the sewer system. The FOG accumulates at different points in the sewer catchment, starting from the kitchen to the pumping stations. They make the wastewater oily, with floating agglomerates and hard deposits [48]. FOG-containing wastewater has high calorific contents on the positive side and is considered a potential feedstock for energy recovery processes. Therefore, prior knowledge of the wastewater quantity and volume is necessary to develop an economically viable solution for their collection and design efficient energy recovery processes. Usually, FOG waste is collected from households, food service establishments (FSEs), and sewage pumping stations in the form of FOG-rich sewage sludge [49]. For example, the amount of FOG recovered from the Thames Water utility catchment in the UK is ~ 9.4 × 104 tons per year. In addition, 222 GWh of biogas per year is produced from FOG-rich sludge [50]. More than six million households in this catchment can contribute to the generation of 7.9 × 104 tons per year of FOG wastes than 1.4 × 104 tons per year from private homes [49, 50].

Dairy products processing wastewater

This type of wastewater is generated in huge quantities from the dairy sector, i.e., during milk processing (ratio varying between 1:1 and 1:5 the volume of milk processed: volume of wastewater generated) (Fig. 2). This wastewater contains BOD values as high as 2.5 kg BOD/t, milk, N, P, and Cl. In a recent study, the effect of high-frequency ultrasonication was examined for the recovery of lipids from wastewater of a cheese manufacturing plant [51]. The authors tested two frequencies (500 kHz and 1 MHz), two temperatures (22 and 40 °C), and different energy densities: 7.5, 30.2, 60.5, and 121 J/mL at 500 kHz 7.9, 32, 63.4, 127 J/mL at 1 MHz, respectively. These energy densities correspond to 30, 120, 240, and 480 s of the sonication process to create and recover the lipids. In that study, the sonication test was carried out using a single plate transducer and the reflector system at 40 W created a standing wave to coalesce and flocculate the lipid globules [52]. Some reports have achieved higher lipid recovery rates at 40 °C after 480 s of sonication (77% at 500 kHz and 75% at 1 MHz). However, at 22 °C and 500 kHz, the lowest lipid recovery was observed (47%) at all the applied energy densities [51, 52]. Nevertheless, the high-frequency ultrasound causes changes in particle size and turbidity, leading to coagulation or aggregation and settling of the colloidal particles.

Fig. 2
figure2

Treatment of dairy wastewater and the role of lactic acid bacteria for polylactic acid (PLA) synthesis

In recent years, dairy industries have been applying AD for energy recovery in the form of biomethane, and such initiatives measure the industries’ environmental performance [53]. In the literature, material flow analysis (MFA) and life cycle analysis (LCA) have been carried out in full-scale AD units treating dairy industry wastewater [54]. From a resource recovery viewpoint, electricity (426 MWh/annum) and heat energy (1236 MWh/annum) are generated from AD plants using this type of wastewater. Thus, 20% of the energy required for the operation of the industry is recovered, and there is a significant reduction of the total carbon footprint emission (13%) compared to the baseline scenario [53, 54].

Sugar processing wastewater

During the process of sugar extraction, large volumes of high strength wastewater are produced, e.g., COD ~ 20,000 mg/L) [55]. The removal of COD or color (> 90%) can be achieved by electrochemical method under the following condition: pH 6.0, enter-electrode gap 20 mm, current density 156 A/m, electrolyte concentration 0.5 M and reaction time 120 min [56]. However, the sludge formed after the treatment contains fewer organic matters in this process and can be used as a fertilizer. Another option produces biohydrogen from sugar industry effluents using a dual-chamber microbial electrolysis cell (MEC). In a recent study, biohydrogen production tests using different cathodic materials was reported in the literature (Ni-plate, Ni-foam, and stainless-steel mesh) [57]. The authors measured the MEC's hydrogen production quantity or recovery, columbic efficiency, and COD removal efficiency. At an applied voltage of 1 V and using Ni-foam as the cathode, the hydrogen production was 1.6 and 1.43 mmol/L/d using cane sugar and raw sugar effluents, respectively [58].

Impacts and benefits of wastewater treatment

By adopting the best available/appropriate technologies, the toxic pollutants from all the wastewater sources discussed earlier can be removed. These wastewaters also serve as an essential feedstock for resource recovery [59]. However, wastewater treatment aims to remove the COD and BOD. A more sustainable bio-economy is achieved by monetizing the wastewater potential to recover energy, nutrients, and other value-added products. Hence, water should be managed carefully during every part of the water cycle, starting from freshwater abstraction, pretreatment, collection, distribution, domestic/industrial use, wastewater discharge, wastewater collection and wastewater treatment [58, 59].

Wastewater generation in cities

In some low-income areas of cities or towns in developing countries, a large portion of the wastewater is directly discharged into the closest surface water drains or informal drainage channel with little or almost no prior treatment. This wastewater contains human wastes, hospital wastes, and commercial/industrial (small scale mining, metal processing, metal plating, or motor garage) wastes [59]. Wastewater is collected and treated in urban areas according to the capacity of the treatment plant and the various primary, secondary, and tertiary treatment technologies available. Water used by the municipal authority, e.g., for watering green spaces or cleaning streets, does not require a high degree of treatment similar to potable standards. However, adequate and extensive wastewater treatment is necessary when the water is considered a resource and if the treated water is expected to be discharged into rivers, canals, and other water bodies [60]. The rising demand for urban water could be met only if new approaches for wastewater collection and management are implemented. Besides, social and environmental pressures have led to the development of water-related industries and the emergence of ecological/environmental consultants who provide technical services to treat water [61].

Wastewater is now seen as a potential resource rather than as a waste. 70% of the world population expects to live in cities by 2050 compared to today's status of 50%. It can create problems due to inadequate infrastructure and inefficient ways of treating and managing wastewater. According to the current status, 1.8 billion people are at the risk of contracting cholera, dysentery, typhoid, or other diseases. At the same time, the rivers in Africa, Asia, or Latin America are heavily contaminated due to the direct discharge of domestic/industrial wastewater into the river [62]. Eco-industrial park (EIP) networks, where the concept of industrial symbiosis (between multiple business establishments) is implemented, make use of wastewater as a feedstock or raw material. Industrial water consumption is responsible for 22% of the global water use. For example, Europe and North America consume nearly 50% of water to meet their industrial demand compared to developing countries (4–12%). An increase in industrial establishments in a country can contribute to a fivefold increase in the wastewater generation rates. Therefore, new businesses are created to treat the wastewater near the vicinity of the generation site and reuse the treated water for cooling or heating, toilet flushing, irrigation, and automobile washing purposes [63].

Wastewater components and their effects

Wastewater contains 99.9% water and 0.1% N or P as nutrients. Besides, it includes FOGs, cooking oils, persisting organic pollutants, endocrine-disrupting chemicals, micro-pollutants, and disease-causing bacteria or viruses as pathogens. The presence of sediments and other toxic substances from the scouring of roads during the rainy seasons, parking lots, rooftops can also affect the river and lake ecosystems [64]. Thus, the decaying fraction of organic matter or debris uses the oxygen in a lake or pond, thereby affecting the survival of the fish or other aquatic organisms. Wastewater also contains nutrients that induce eutrophication, and it has shown to cause a decline in certain marine species in different water bodies [65]. Besides, chlorine and inorganic chloramines are toxic for aquatic invertebrates, algae, and fish species. If the wastewater contains poisonous metals such as mercury, lead, cadmium, chromium, or arsenic, it could easily cause chronic health effects on the aquatic species. The presence of pharmaceutical or personal care products (PCPs) in wastewater also poses a significant, long-term negative health effect on humans and the ecosystem, including wildlife [66, 67].

Hence, the wastewater should be adequately treated to minimize/prevent health-related issues and environmental impacts. If the wastewater contains high FOGs, traditional grease interceptors trap the FOG, and the accumulated FOG are removed manually. Other FOG removal processes are filters, membranes, hydromechanics grease interceptors, and gravity-based grease interceptors [68]. Thus, from the viewpoint of wastewater treatment and reuse for irrigation, several agencies, including the USEPA, the EU, and the WHO, have recommended strict guidelines and provided suitable solutions for setting up a good water management strategy by considering the local conditions [69]. For example, the treatment of wastewater using a hydroponic system is one of the promising biotechnologies for food production. Several plant species have shown good growth capacities in a hydroponic system fed with sewage [70].

Environmental factors influencing the wastewater characteristics and its impact on agriculture

Table 1 provides detailed information on the different wastewater treatment strategies and environmental factors for the removal of nutrients and toxic pollutants. As mentioned previously, the treated domestic and industrial wastewater are used for agricultural purposes with careful planning and management [70]. When applied to soils, the residual, non-treated pollutants present in low concentrations are easily removed by the soil, thereby reducing/preventing the environmental impacts on surface/groundwater bodies. Besides, the nutrients present in the wastewater can offset or replace the requirement of chemical fertilizers without damaging the soil structures [71]. Nevertheless, the soil characteristics could substantially change due to the treated waters salt or heavy metal content, i.e., from industrial sources. Therefore, in some cases, the treated industrial wastewater is mixed with domestic sewage and directly applied on agricultural lands [72]. From a resource recovery viewpoint, it is always advisable to look for potential options wherein value-added products such as biopolymers can be recovered and commercialized for practical applications.

Table 1 Wastewater treatment strategies for the removal of waste organic matters from different sources

Biopolymers

Many living organisms produce biopolymers, and they are usually present as natural polymers. Biomolecules are generated in the form of cellular or extracellular products during microbe-mediated biochemical reactions. Biopolymers have shown good biocompatibility, biodegradability, and environmental or human compatibility [73]. Due to their unique physicochemical properties, biopolymers are presently used in gas sensors, and for developing electrical noses for application in environmental or disease monitoring, defense, and public safety [74]. The different applications of biopolymers are shown schematically in Fig. 3.

Fig. 3
figure3

The application of biopolymers in different industrial sectors

The use of biopolymers in gas sensors is a common example of their application. It contains biopolymer films as well as self-assembled monolayers of biopolymers or biopolymer films that have been doped with carbon nanoparticles. Sensors that detect gases or toxic vapors made of carbon nanotubes modified with biopolymers have also been reported. In both these examples, the sensitivity, selectivity, response time, or reversibility of biopolymers-based sensors is very high, and they have shown better performance [75]. A wide variety of biopolymers are produced from renewable carbon substrates, including wastewaters rich in nutrients. Anew, in microorganisms, the production of biopolymers has several proven functions: (i) maintaining the cell viability by converting the genetic information, (ii) storing carbon-based macromolecules, (iii) production of energy, and (iv) protecting the microorganism from hazardous/toxic chemicals and harsh environmental conditions [76]. From a biochemistry viewpoint, biopolymers are classified based on the structure of their monomers; for instance, polysaccharides and polyamides (protein or poly-l-glutamic acid-l-PGA), nucleic acids (RNA or DNA), polyesters, polyhydroxyalkanoates, polyphosphates, and polyisoprenoid (natural rubbers) [77]

Various forms of biopolymers can be produced by bacterial fermentation. Biopolymers are being used at the commercial scale for a wide range of applications, including food, pharmaceuticals, plastics, and agricultural products, among others. Refined carbohydrates, agricultural or dairy byproduct as substrates are used to synthesize various biopolymers [78]. However, it is noteworthy to mention that the structural and chemical composition of biopolymers is rather complex. Their production costs at the commercial scale are very high compared to chemically synthesized polymers exhibiting similar characteristics [79]. Therefore, the development of bioprocesses for the production of biopolymers is achieved by optimizing the upstream (e.g., fermentation process) or downstream purification and recovery lines and by applying engineering strategies such as metabolic or cellular engineering of the host cells [80].

Food-grade biopolymers

Food-grade biopolymers have shown to enhance the inherent nutritional properties, improve food quality, and serve as delivery vehicles for bioactive compounds or novel packaging components. In addition, this approach can improve the transport properties of bio-based packaging materials [81, 82]. For example, synthetic hydrogel-based polymers are used to develop films, coatings, extrudable pellets, or synthetic nanopolymers with medical, agricultural, or industrial applications. Edible biopolymers are commonly used for delivering drugs and tissue engineering products produced from wastewater nutrients [83]. Edible films or coatings are biosynthesized from food-grade biopolymers. At present, carbohydrates, protein, and lipids (stand-alone or binary or ternary combinations) are utilized to develop composite biofilm layers [84]. These products are used for the packaging of fruits and vegetables: dairy and meat products, fishes and seafoods [83, 84].

Some food-grade biopolymers such as α-PGA are synthesized using chemical methods, while microbe-mediated processes are used for g-PGA production using Bacilli species. α-PGA and g-PGA isomers are used for drug delivery. PGA nanoparticles are used in the food and medical sectors [85]. For example, the PGA nanoparticles are applied for cancer chemotherapy and tissue engineering. g-PGA is used as a thickener, cryoprotectant, humectants, drug carrier, biological adhesive, heavy metal absorbent, and flocculant. It is commonly used in the food, cosmetic, and medical sectors [86, 87].

Microbial synthesis of biopolymers

Bacterial fermentation process has also been used to produce biopolymers. Bacterial exopolysaccharides i.e., dextran xanthan and gellan production have been reported at the commercial scale. Starch, cellulose, or curdlan have been used to synthesize biodegradable plastics. Table 2 discusses the different types of biopolymers synthesized from wastewater nutrients [88]. Curdlan is reported as a water-insoluble linear β-1,3-glucans, and it contains high-molecular weight polymers of glucose. Several other bioproducts are fungal or bacterial exopolysaccharides (EPS) that can be obtained during biological wastewater treatment [89,90,91]. There are reports on producing several high-yielding alginates from bacterial cells and other novel exopolysaccharides producing microbial strains. Other microbial polysaccharides such as xanthan from Xanthomonas compestis are also reported in the literature. Pullulan also exhibits good chemical and physical properties, and it has several industrial applications.

Table 2 Biopolymers production from wastewater nutrients using biological reactors

The microbe-mediated biochemical reactions and processes are used for the production of polyhydroxyalkanoates (PHA) [92]. This process exposes various ecological niches for the treatment of wastewater containing high organic loads from the dairy industry, olive mills, pulp and paper mills, the treatment of hydrocarbon-contaminated sites, and the treatment of solid wastes. The production of extracellular by-products such as rhamnolipids, extracellular polymeric substances, biomethane and biohydrogen is also accomplished in parallel using one or two combinations of aerobic/anaerobic bioprocesses [90, 92].

The following examples illustrate the reactor configurations and their operating conditions for the production of PHA: (i) A continuous feed and intermittent discharge airlift bioreactor (CFIDAB) was operated at a hydraulic retention time (HRT) of 12–24 h, and at an air flow rate of 1–3 L/min, wherein TCOD (92%), TP (71%) or TN (69%) was achieved and the accumulation of PHA was observed [93, 94], (ii) three different types of carbon sources (34.2% acetate containing wastewater, 4.8% soft drinks wastewater, and 11.3% Faraman industrial wastewater) were tested in a single-stage suspended growth bioreactor and the production of PHA was observed after 2 weeks of reactor operation [95], (iii) rice winery wastewater at different organic loading rates (OLRs) were tested in three sequencing batch reactors (SBRs) and the highest PHA yield (0.23 g/g) was observed at an OLR of 2.4 g COD/L/d [96, 97], and (iv) using a long-term operated (225 days) integrated fixed film activated sludge (IFAS) reactor of pilot-scale capacity (500–800 L), PHA was produced (49%) during the treatment of municipal wastewater nutrients and the removal of carbon and nitrogen was achieved [98, 99]. These studies clearly show the effect of different factors that would contribute to enhanced PHA production and good treated water characteristics. These include, amongst others: (a) type of substrate, (b) enrichment of PHA producing biomass, (c) variability of feed/influent characteristics, (d) nitrification of biofilms at relatively low solids retention time (SRT), (e) biomass yield, and (f) the carbon/substrate conversion efficiencies [99].

Nevertheless, commercializing PHA production at the industrial scale (i.e., using bioreactors) attracts business investments and a techno-environmental assessment opportunity and therefore, it must be performed. In addition to improving the wastewater treatment plants environmental performance, an evaluation should be done on the PHA production capacity/yield, life cycle analysis, carbon, nitrogen, and energy balance [100]. Several studies have evaluated the techno-environmental performance of different bioreactor configurations, and the following results were reported:

  1. 1.

    Global warming and acidification, and terrestrial eutrophication have been reported. The photo-oxidant forming potential was evaluated during PHA-rich biomass production and biogas production was achieved in an anaerobic digestion unit treating municipal wastewater treatment plant sludge [15].

  2. 2.

    The freshwater and marine eutrophication potentials depend on the effluent composition/characteristics, and the PHA-rich biomass produces fewer aeration requirements for COD or nitrogen removal [101, 102].

  3. 3.

    Nitrogen removal (via nitrification–denitrification), energy balance, and PHA production are sensitive to primary treatment efficiency. If the immediate treatment unit or the pre-treatment step is optimized, more value-added products such as biogas, or heat energy can be obtained [102]. Table 3 shows few examples of the application of biopolymers in various sectors.

Table 3 Biopolymers, their derivatives and applications in various sectors

In some previous reports, PHA production has been optimized and demonstrated in full-scale systems. Some examples of such bioprocesses are mentioned as follows: (i) at the Brussels North wastewater treatment plant (WWTP), municipal wastewater was treated for 22 months using a feast–famine strategy, and the biomass accumulated PHA (0.4 g PHA/gVSS) from volatile fatty acid (VFA) rich fermented sludge at 42 °C, resulting in 70% COD, 60% CODsol, 24% nitrogen, and 46% phosphorus removal [103], (ii) batch fermentation of WWTP sludge at different temperatures of 35, 42, and 55 °C produced VFA in the range of 6.0–9.4 gCODVFA/L and 0.39 g PHA/g VSS, and optimal performance was achieved at 42 °C [104], (iii) maximum PHA content (~ 0.76 g PHA/g VSS) was achieved using fermented wastewater containing ethanol and Plasticicumulans acidovorans was observed as the dominant PHA producing microorganism in an anaerobic bioreactor [105], (iv) in anaerobic fermenters and under alternating anaerobic–aerobic conditions in sequencing batch reactors, VFA (0.64 g COD/g COD), ethanol (022 g COD/g COD) and nitrogen were treated in cycles of 12 h, at an SRT of 24 h, under feast and famine conditions to produce PHAs [106, 107], and (v) in another study, two different carbon sources (acetate and wastewater from a soft drinks company) was treated in a bioreactor with carbon/nitrogen feeding regimes and higher PHA accumulation was observed using acetate (79% mg PHA/mg TSS) compared to soft drink wastewater (25% mg PHA/mg TSS) [108].

Potential for the recovery of nutrients and PHA

According to a recent study, wastewater containing high organic content prefers PHA biosynthesis and resource recovery (e.g., treatment of mussel processing wastewater in an SBR) [109]. During the settling phase of SBR operation, the washout of non-accumulating microbial cells and removing undesired products (protein or carbohydrates) is achieved, and PHA is recovered as concentrates. In another study, during the treatment of saline industrial wastewater, PHA production yields are YPHA ~ from 0.48 to 0.72 C mmol PHA/Cmmol VFA).

The maximum PHA storage capacity (PHA ~ 40–60 wt%) was reported using mixed cultures in an SBR operated in cycles of feast/famine phases. Thus, during the settling step, i.e., after the feast phase, the washout of non-PHA storing bacterial cells was achieved [110]. PHA accumulation occurred at higher substrate loads (40% of the weight of the dry cell, DCW), low nitrogen (45% DCW), and low phosphorus (54% DCW) conditions [111]. In another study, under optimal nutrient conditions, the production of PHA was reported to be only 14% [112]. The authors determined the fractional composition of the PHA copolymers [poly(β-OH) butyrate-co-poly(β-OH) valerate, P3(HB-co-HV), and it contained PHB ~ 80% to PHV ~ 8%, respectively. In that study, during PHA production, high COD reduction (75%) was achieved based on phylogenetic profile analysis using 16S rRNA. The authors reported that Firmicutes (71.4%) and Proteobacteria (28.5%) were dominant during PHA accumulation and wastewater treatment [105, 107]. Thauera species with aerobic dynamic feeding steps are the dominating microbial species during PHA accumulation (65% DCW) in continuously operated bioreactors [113].

In some reports, the variation of wastewater composition has shown to influence the PHA production/accumulation; e.g. the wastewater from a yeast-producing industry. According to the findings of a study conducted in an SBR, high concentrations of ammonium inhibited PHA biosynthesis under a dynamic aerobic feeding regime [114]. Industrial wastewater treated in batch (72% DCW) or continuous feeding modes (65% DCW) also affects PHA production. For example, lower PHA accumulation was observed in continuous mode despite a fourfold increase in biomass concentration than the batch mode of operation [115]. These examples indicate that the feedings strategies/regimes, reactors operational conditions, feast/famine conditions, and the type of biomass influence the PHA production [116].

Future research should focus on evaluating different feedstocks to produce biopolymers/bioplastics, such as from agricultural residues, waste cooking oils, oil spills, FOGs, etc. Besides, the efficacy of using mixed microbial cultures, as well as engineered biocatalysts should also be demonstrated to produce bioplastics [117]. Based on the reviewed literature, it is evident that bioplastics have a major role in the “post-oil-era” society. Thus, considering waste (present in water, gas, sediment, and soil) as a “useful feedstock” or a “resource”, and using the best available technologies (BAT), new biomaterials and biofuels could offer sustainable solutions to preserve the earths natural resources.

From a technological perspective, process intensification should be researched in the future by combining several technologies to produce PHA from different feedstocks, and by adopting intelligent process control strategies to maintain the aerobic/anaerobic or microaerophilic conditions in the bioreactors [116].

Technologies for the treatment of industrial effluents coupled to the removal and recovery of nutrients

The treatment methods followed for a specific industrial effluent rely on the influents composition and the thresholds set for the effluents, i.e., the local discharge limits. The technical, economic, and operational feasibility of the selected techniques are essential for process optimization and the future application of recovered valuable products at the commercial scale. Mehta et al. [118] recommended a three-step technology for nutrient recovery from waste streams, in sequential order of nutrient accumulation, nutrient release, and nutrient extraction, respectively. According to the authors, each step can have several options for treatment based on the type of industry, nature of effluents, and the final discharge and recovery requirements [118].

Diverse membrane-based technologies have been shown to be highly selective for the recovery of phosphorus and nitrogen from wastewater. The following are examples of reactors that are commonly used: hollow-fiber membrane contactors (HFMC), forward osmosis (FO), electrodialysis (ED), and bioelectrochemical systems (BES) [119]. As a proceeding step to fertigation and other nutrient recovery systems, anaerobic membrane bioreactors (AnMBR) and direct membrane filtration (DMF) have been recommended [120]. According to a recent study, the application of divalent magnesium chloride as a draw solution could recover 75% of phosphate (PO 3-4 ) and 66% of ammonia (NH3, FAN) [121], respectively. HFMC is usually applied for the successful recovery of N [120]. Ultrafiltration using membranes retains the majority of the pathogens, including viruses, making it a cost-effective alternative for wastewater regeneration/reuse [120, 121]. Struvite crystallization has demonstrated significant, economically efficient recovery of P, generating saleable products with less environmental impact, compared to processes such as electrochemical, biological, membrane systems, and ion exchange [122]. Dilute waste streams with low solids content (< 2000 mg/L), and P concentrations > 50–60 mg P-PO4/L has shown to improve the rate of phosphate recovery [118, 123].

Another crystallization-based method is the vivianite (Fe3(PO4)2·8H2O) precipitation which utilizes Fe salts as a chemical flocculant to precipitate P [120]. Two chemical-free treatment methods that are fast gaining prominence are microalgae-based and photosynthetic bacteria-based treatment technologies. Microalgal cultures recover up to 90% of nutrients from the effluents and are less energy consuming (about 24% lesser) than the conventional treatment units [124]. Green microalgae (e.g., Chlorella sp., Monoraphidium sp. and Scenedesmus sp.) are suitable for wastewater treatment due to their high adaptability to this medium [114, 125]. Besides, valuable biomass is obtained/recovered, ranging from 1 to > 10 kg of dry microalgae per cubic meter of sewage and manure, respectively [126].

This microalgal biomass is converted to renewable energy sources such as biodiesel, biogas, bioethanol, and biohydrogen [127] and for the production pigments, proteins, vitamins, and omega fatty acids [128]. This biomass also finds application in the agriculture industry as a fertilizer [129]. Photosynthetic bacteria (PSB)-based technology assimilates the organic pollutants. Polyhydroxybutyrate (PHB) forms inorganic polyphosphate, leading to P recovery. This technology also facilitates simultaneous denitrification and assimilation, leading to N recovery [130]. PSB, especially the purple non-sulfur bacteria (PNSB), exhibits temperature and toxicity tolerance, gives a high hydrogen yield, and assimilates C, N, and P in a single stage of their metabolic pathway, unlike microalgae [131]. It is noteworthy to mention that the PSB-based treatment is still at its infancy stage, and it will have to undergo several considerations before upscaling at the commercial scale. Thus, based on literature evidence, the harvesting of microalgae and PSB from continuously operated bioreactors still need process optimization and downstream purification. Anew, the photo-granular/photo-activated sludge-based processes and membrane photobioreactors should be tested in real environments to realize its full potential at the semi-industrial and industrial scales [120].

Pesticide use reduces pest damage and, consequently, crop losses. Frequent pesticide use has a detrimental effect on the environment, owing to pesticide accumulation and its persistent nature. Microalgal species cultivation technology can also be used to effectively treat pesticide-contaminated sites. The metabolic functions of the different microbes involved in the removal of pesticides have been summarized in several reports [131]. Additionally, various cultivation techniques can be used to boost microalgal cell growth and their ability to remove pesticides. After wastewater treatment is accomplished, it is used to recycle microalgal biomass that aids in the preparation of biochar and biodiesel biosynthesis. Additionally, it can be used in biorefinery approaches/techniques. It has the potential to improve pollution abatement and facilitate the biosynthesis of high-value-added products [132]. The authors have also examined different algal processes with the goal of generating biodiesel, biobased products, and biofuels [132]. Additionally, some pretreatment and saccharification methods for algal biomass were also discussed together with fermentation, gasification, and pyrolysis processes, as well as hydrothermal liquefaction and anaerobic digestion [132]. These approaches/processes aided in the biosynthesis of hydrogen, biooils, biomethane, and biochar (BC), as well as a variety of other biobased products. For example, 1 kg of oil derived from algal biomass is said to be capable of producing one kg of biodiesel. The yield of biochar per unit dry weight of algal biomass is between 8.1 and 62.4%. The algal-based research can assist in addressing the primary challenge of developing the third generation of biofuels in a cost-effective manner in the future. Table 4 summarizes the various techniques for the biosynthesis of value-added products, including biopolymers [133].

Table 4 Various techniques/approaches for the synthesis of value-added products from different wastewater sources and the results achieved in different studies

Future research prospects and perspectives

Wastewater treatment and reuse vary significantly between the high-income and low-to-middle-income economies in the world. The governmental incentives, involvement of stakeholders, funding from regional partners, availability of monitoring resources, the social and legal framework play an influential role in the successful operation of wastewater treatment units, which is often a hindrance in developing nations. Therefore, more environmentally friendly, resilient techniques/technologies should be developed and implemented in order to reduce the toxic contaminant levels in the treated effluent, primarily when the treated water is used for irrigation. Membrane-based systems can emerge as one of the most reliable, economically feasible technologies for wastewater treatment and nutrient recovery, following improvements concerning membrane fouling, power consumption, the economic viability of regenerated products, carbon footprint, etc. Phosphorus and nitrogen recovery, for example, is beneficial for the agriculture industry, as they are directly applied to arable lands as low-cost fertilizers. The profits thus generated can balance the capital costs of such recovery systems. Therefore, the recovery of nutrients directly links to value-added products that meet societal needs (e.g. fertilizers for the farming community) and make products sold in the relevant markets. However, there is further scope for cost–benefit analysis and life-cycle impact assessment on all the treatment technologies as mentioned in Table 4.

Conclusions

This review highlighted the application of wastewater as a feedstock (resource) which contains large quantities of organic matter, N, P, K, and suspended solids. It also reviewed the potentials of nutrients recovery from different types of wastewater, including fruit, vegetable, meat, and seafood processing wastewaters. Some industrial wastewaters are severely polluted with toxic chemicals and heavy metals, and they are also a source of disease-causing bacteria and parasites. However, innovative and advanced technologies efficiently recover value-added products such as biofuels, bioplastics, biofertilizers, and heavy metals from industrial wastewater. The biosynthesis of PHA, its recovery, and its application in different sectors was also reviewed. From a practical viewpoint, the involvement of other stakeholders (e.g., water authorities, sewage works department, Ministry of Environment) at the regional and national levels is essential to support the transition of converting wastewater and domestic sewage into useful biomaterials, sustainable energy (e.g., biogas, bioelectricity) and water for reuse.

Abbreviations

ABR:

Anaerobic Baffled Reactor

AD:

Anaerobic Digestion

AgNPs:

Silver Nanoparticles

AGS:

Aerobic Granular Sludge system

Al:

Aluminum

ALE:

Alginate-like Exopolymers

ASCs:

Adipose‐derived Stem Cells

BNR:

Biological Nutrient Removal

BOD/t:

Biological Oxygen Demand per time

BOD:

Biological Oxygen Demand per time

BPA:

Bisphenol A

C:

Carbon

Ca2 + :

Calcium ion

CE:

Coulombic Efficiency

CFIDAB:

Continuous Feed and Intermitted Discharge Airlift Bioreactor

Cl :

Chloride ion

COD:

Chemical Oxygen Demand

COD/L/d:

Chemical Oxygen Demand per liter per day

CODVFA/L:

Chemical Oxygen demand Volatile Fatty Acids per liter

DCW:

Dry Cell Weight

DI:

Dairy Industries

DNA:

Deoxynucleic acid

EAM:

Enterprise Asset Management

EC:

Electrocoagulation

EPS:

Expolysccharides

Fe:

Iron

FIW:

Food Industry Waste

FOGs:

Fats, Oils, and Grease

FSEs:

Food Service Establishments

g PHA/g VSS:

Grams of PolyHydroxyAlkanoates per gram of Volatile Suspended Solids

g VS/L/d:

Grams of Volatile Solids per liter per day

GWh:

Giga watts hour

H2/g VS:

Hydrogen per gram of Volatile Solids

HRT:

Hydraulic Retention Time

IFAS:

Integrated with Fixed Films Activated Sludge

ITC:

Isothermal Titration Calorimetry

K:

Potassium

KB:

Keratin-derived Biopolymers

kg COD/d:

Kilograms of Chemical Oxygen Demand per day

kg SS/d:

Kilograms of Suspended Solids per day

kHz:

Kilo Hertz

LCA:

Life Cycle Analysis

l-PGA:

Poly-l-Glutamic Acid

ME:

Micro-Electrophoresis

MEC:

Microbial Electrolysis Cell

MFC:

Microbial Fuel Cell

mg TSS:

Milligram of Total Suspended Solids

mg/L:

Milligram per liter

MHz:

Mega Hertz

MMC:

Mixed Microbial Culture

mmol/L/d:

Millimole per liter per day

N:

Nitrogen

N-NH +4 :

Nitrogen ammonium ion

OLRs:

Organic Loading Rates

P:

Phosphorus

PCL:

Polycaprolactone

PD:

Power Density

PEG:

Polyethyl Glycol

PEP:

PHA Accumulation Potential

PES:

Polyethersulfone

PGA:

Polyglutamic acid

PHA:

Polyhydroxyalkanoates

PHB:

Hydrooxybutyrte

PLA:

Polylactic acid

PO4-P:

Phosphate phosphorus

QMRA:

Quantitative Microbiological Risk Assessment

RNA:

Ribo Nucleic Acid

RO:

Reverse Osmosis

SBR:

Sequencing Batch Reactor

SEC:

Sono-Electro-Coagulation

SRT:

Solids Retention Time

SS:

Suspended Solids

STWs:

Sewage Treatment Wastes

TCOD:

Total Chemical Oxygen Demand

TDS:

Total Dissolved Solids

TKN:

Total Kjeldahl Nitrogen

TN:

Total Nitrogen

TOC:

Total Organic Carbon

TP:

Total Phosphorus

$/m3 :

US dollar per meter cube

UNESCO:

United Nations Educational, Scientific and Cultural Organization

US:

Ultrasonication

US:

United States

VFAs:

Volatile Fatty Acids

VS:

Volatile Solids

WWTP:

Wastewater Treatment Plant

ε-PL:

ε-Polylysine

References

  1. 1.

    Goberna M, Simón P, Hernández MT, García C. Prokaryotic communities and potential pathogens in sewage sludge: response to wastewater origin, loading rate and treatment technology. Sci Total Environ. 2018;615:360–8. https://doi.org/10.1016/j.scitotenv.2017.09.240.

    CAS  Article  PubMed  Google Scholar 

  2. 2.

    Miao L, Yang G, Tao T, Peng Y. Recent advances in nitrogen removal from landfill leachate using biological treatments—a review. J Environ Manag. 2019;235:178–85. https://doi.org/10.1016/j.jenvman.2019.01.057.

    CAS  Article  Google Scholar 

  3. 3.

    He Z, Pagliari PH, Waldrip HM. Applied and environmental chemistry of animal manure: a review. Pedosph. 2016;26(6):779–816. https://doi.org/10.1016/S1002-0160(15)60087-X.

    CAS  Article  Google Scholar 

  4. 4.

    Cid CA, Jasper JT, Hoffmann MR. Phosphate recovery from human waste via the formation of hydroxyapatite during electrochemical wastewater treatment. ACS Sustain Chem Eng. 2018;6(3):3135–42. https://doi.org/10.1021/acssuschemeng.7b03155.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  5. 5.

    Xu E, Campanella OH, Ye X, Jin Z, Liu D, BeMiller JN. Advances in conversion of natural biopolymers: a reactive extrusion (REX)-enzyme-combined strategy for starch/protein-based food processing. Trends Food Sci Technol. 2020;99:167–80. https://doi.org/10.1016/j.tifs.2020.02.018.

    CAS  Article  Google Scholar 

  6. 6.

    Wang X, Oehmen A, Carvalho G, Reis MAM. Community profile governs substrate competition in polyhydroxyalkanoate (PHA)-producing mixed cultures. New Biotechnol. 2020;58:32–7. https://doi.org/10.1016/j.nbt.2020.03.003.

    CAS  Article  Google Scholar 

  7. 7.

    Kavitake D, Balyan S, Bruntha P, Prathapkumar D, Shetty H. Interface between food grade flavour and water soluble galactan biopolymer to form a stable water-in-oil-in-water emulsion. Int J Biol Macromol. 2019;135:445–52. https://doi.org/10.1016/j.ijbiomac.2019.05.199.

    CAS  Article  PubMed  Google Scholar 

  8. 8.

    Li Y, Gao F, Guo J, Ren P, Tian Z, Bai J, Hu J. Polymeric micelles with aggregation-induced emission based on microbial ε-polylysine for doxorubicin delivery. Euro Polymer J. 2020;122:109355. https://doi.org/10.1016/j.eurpolymj.2019.109355.

    CAS  Article  Google Scholar 

  9. 9.

    Kumar M, Ghosh P, Khosla K. Thakur1S, Recovery of polyhydroxyalkanoates from municipal secondary wastewater sludge. Bioresour Technol. 2018;255:111–5. https://doi.org/10.1016/j.biortech.2018.01.031.

    CAS  Article  PubMed  Google Scholar 

  10. 10.

    Kumar M, Ghosh P, KhoslaIndu K, Thakur S. Biodiesel production from municipal secondary sludge. Bioresour Technol. 2016;216:165–71. https://doi.org/10.1016/j.biortech.2016.05.078.

    CAS  Article  PubMed  Google Scholar 

  11. 11.

    Kumar M, Kumar M, Pandey AK, Thakur IS. Genomic analysis of carbon dioxide sequestering bacterium for exopolysaccharides production. Sci Rep. 2019;9:4270. https://doi.org/10.1038/s41598-019-41052-0.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  12. 12.

    Kumar M, Thakur IS. Municipal secondary sludge as carbon source for production and characterization of biodiesel from oleaginous bacteria. Bioresour Technol Rep. 2018;4:106–13. https://doi.org/10.1016/j.biteb.2018.09.011.

    Article  Google Scholar 

  13. 13.

    Kumar M, Rathour R, Singh R, Sun Y, Pandey A, Gnansounou E, Lin K-YA, Tsang DCW, Thakur IS. Bacterial polyhydroxyalkanoates: opportunities, challenges, and prospects. J Clean Product. 2020;263:121500. https://doi.org/10.1016/j.jclepro.2020.121500.

    CAS  Article  Google Scholar 

  14. 14.

    Deepnarain N, Nasr M, Amoah ID, Enitan-Folami AM, Reddy P, Stenström TA, Kumari S, Bux F. Impact of sludge bulking on receiving environment using quantitative microbial risk assessment (QMRA)-based management for full-scale wastewater treatment plants. J Environ Manag. 2020;267:110660. https://doi.org/10.1016/j.jenvman.2020.110660.

    CAS  Article  Google Scholar 

  15. 15.

    Mohapatra S, Pattnaik S, Maity S, Mohapatra S, Sharma S, Akhtar J, Pati S, Samantaray DP, Varma A. Comparative analysis of PHAs production by Bacillus megaterium OUAT 016 under submerged. Saudi J Biol Sci. 2020;27(5):1242–50. https://doi.org/10.1016/j.sjbs.2020.02.001.

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  16. 16.

    Bitter H, Lackner S. First quantification of semi-crystalline microplastics in industrial wastewaters. Chemosphere. 2020;258: 127388. https://doi.org/10.1016/j.chemosphere.2020.127388.

    CAS  Article  PubMed  Google Scholar 

  17. 17.

    Zhang X, Qi M, Chen L, Wu T, Zhang W, Wang X, Tong Y. Recent change in nutrient discharge from municipal wastewater in China’s coastal cities and implication for nutrient balance in the nearshore waters. Estuar Shelf Sci. 2020;242: 106856. https://doi.org/10.1016/j.ecss.2020.106856.

    CAS  Article  Google Scholar 

  18. 18.

    Akansha J, Nidheesh PV, Gopinath A, Anupama KV, Kumar MS. Treatment of dairy industry wastewater by combined aerated electrocoagulation and phytoremediation process. Chemosphere. 2020;253: 126652. https://doi.org/10.1016/j.chemosphere.2020.126652.

    CAS  Article  PubMed  Google Scholar 

  19. 19.

    Zheng J, Kamal MA. The effect of household income on residential wastewater output: evidence from urban China. Utilit Polic. 2020;63: 101000. https://doi.org/10.1016/j.jup.2019.101000.

    Article  Google Scholar 

  20. 20.

    Srivastava RK. Bio-energy production by contribution of effective and suitable microbial system. Mater Sci Energy Technol. 2019;2:308–18. https://doi.org/10.1016/j.mset.2018.12.007.

    Article  Google Scholar 

  21. 21.

    Melo RG, Andrade AF, Bezerra RP, Correia DS, Souza VC, Brasileiro-Vidal AC, Viana-Marques DA, Porto A. Chlorella vulgaris mixotrophic growth enhanced biomass productivity and reduced toxicity from agro-industrial by-products. Chemosphere. 2018;204:344–50. https://doi.org/10.1016/j.chemosphere.2018.04.039.

    CAS  Article  PubMed  Google Scholar 

  22. 22.

    Dar RA, Parmar M, Dar EA, Sani RK, Phutela UG. Biomethanation of agricultural residues: potential, limitations and possible solutions. Renew Sustain Energy Rev. 2021;35: 110217. https://doi.org/10.1016/j.rser.2020.110217.

    CAS  Article  Google Scholar 

  23. 23.

    Yang W, Wang X, Son M, Logan BE. Simultaneously enhancing power density and coulombic efficiency with a hydrophobic Fe-N4/activated carbon air cathode for microbial fuel cells. J Power Sourc. 2020;465: 228264. https://doi.org/10.1016/j.jpowsour.2020.228264.

    CAS  Article  Google Scholar 

  24. 24.

    Choudhury P, Ray RN, Bandyopadhyay TK, Bhunia B. Fed batch approach for stable generation of power from dairy wastewater using microbial fuel cell and its kinetic study. Fuel. 2020;266: 117073. https://doi.org/10.1016/j.fuel.2020.117073.

    CAS  Article  Google Scholar 

  25. 25.

    Srivastava RK, Shetti NP, Reddy KR, Kwon EE, Nadagouda MN, Aminabhavi TM. Biomass utilization and production of biofuels from carbon neutral materials. Environ Pollut. 2021;276: 116731. https://doi.org/10.1016/j.envpol.2021.116731.

    CAS  Article  PubMed  Google Scholar 

  26. 26.

    Jampani M, Liedl R, Hülsmann S, Sonkamble S, Amerasingh P. Hydrogeo chemical and mixing processes controlling groundwater chemistry in a wastewater irrigated agricultural system of India. Chemosphere. 2020;239: 124741. https://doi.org/10.1016/j.chemosphere.2019.124741.

    CAS  Article  PubMed  Google Scholar 

  27. 27.

    Ochando-Pulido JM, Martinez-Ferez A. Novel micro/ultra/nanocentrifugation membrane process assessment for revalorization and reclamation of agricultural wastewater. J Environ Manag. 2018;222:447–53. https://doi.org/10.1016/j.jenvman.2018.05.092.

    CAS  Article  Google Scholar 

  28. 28.

    Khandaker S, Toyohar Y, Kamida S, Kub T. Effective removal of cesium from wastewater solutions using an innovative low-cost adsorbent developed from sewage sludge molten slag. J Environ Manag. 2018;222:304–15. https://doi.org/10.1016/j.jenvman.2018.05.059.

    CAS  Article  Google Scholar 

  29. 29.

    Mohajeri P, Smith CMS, Chau HW, Lehto N. Powdered allodust/allochar augmented single batch aerobic reactor (SiBAR) for high concentration phosphorous removal from agricultural wastewater. J Water Proc Eng. 2020;36: 101301. https://doi.org/10.1016/j.jwpe.2020.101301.

    Article  Google Scholar 

  30. 30.

    Srivastava RK, Shetti NP, Reddy KR, Aminabhavi TM. Biofuels, biodiesel and biohydrogen production using bioprocesses. A review. Environ Chem Lett. 2020;18(4):1049–72. https://doi.org/10.1007/s10311-020-00999-7.

    CAS  Article  Google Scholar 

  31. 31.

    Srivastava RK, Shetti NP, Reddy KR, Aminabhavi TM. Sustainable energy from waste organic matters via efficient microbial processes. Sci Tot Environ. 2020;722: 137927. https://doi.org/10.1016/j.scitotenv.2020.137927.

    CAS  Article  Google Scholar 

  32. 32.

    Dizge N, Akarsu C, Ozay Y, Gulsen HE, Adiguzel SK, Mazmanci MA. Sono-assisted electrocoagulation and cross-flow membrane processes for brewery wastewater treatment. J Water Proc Eng. 2018;21:52–60. https://doi.org/10.1016/j.jwpe.2017.11.016.

    Article  Google Scholar 

  33. 33.

    Dias C, Reis A, Santos JAL, da Silva TL. Concomitant wastewater treatment with lipid and carotenoid production by the oleaginous yeast Rhodosporidium toruloides grown on brewery effluent enriched with sugarcane molasses and urea. Proc Biochem. 2020;94:1–14. https://doi.org/10.1016/j.procbio.2020.03.015.

    CAS  Article  Google Scholar 

  34. 34.

    Papadopoulos KP, Economou CN, Tekerlekopoulou AG, Vayenas DV. Two-step treatment of brewery wastewater using electrocoagulation and cyanobacteria-based cultivation. J Environ Manag. 2020;265: 110543. https://doi.org/10.1016/j.jenvman.2020.110543.

    CAS  Article  Google Scholar 

  35. 35.

    Atangana E, Chiweshe TT, Oberholster PJ, Deyse LM. Evaluation of the absorbance capacity of elements in meat effluent, and their mathematical models by using shrimp chitosan cross-linked glutaraldehyde. Alexandria Eng J. 2020;59(4):2567–74. https://doi.org/10.1016/j.aej.2020.04.018.

    Article  Google Scholar 

  36. 36.

    Fagnani KC, Alvesa HJ, deCastro LEN, Kunh SS, Colpi LMS. An alternative for the energetic exploitation of sludge generated in the physico-chemical effluent treatment from poultry slaughter and processing in Brazilian industries. J Environ Chem Eng. 2019;7(2): 102996. https://doi.org/10.1016/j.jece.2019.102996.

    CAS  Article  Google Scholar 

  37. 37.

    Dróżdż D, Wystalska K, Malińska K, Grosser A, Grobelak A, Kacprzak M. Management of poultry manure in Poland—current state and future perspectives. J Environ Manag. 2020;264: 110327. https://doi.org/10.1016/j.jenvman.2020.110327.

    Article  Google Scholar 

  38. 38.

    Willer DF, Aldridge DC. Microencapsulated diets to improve bivalve shellfish aquaculture for global food security. Glob Food Sec. 2019;23:64–73. https://doi.org/10.1016/j.gfs.2019.04.007.

    Article  Google Scholar 

  39. 39.

    Chinnadurai S, Campos CJA, Geethalakshmi V, Sharma J, Kripa V, Mohamed KS. Microbiological quality of shellfish harvesting areas in the Ashtamudi and Vembanad estuaries (India): environmental influences and compliance with international standards. Mar Pollution Bullet. 2020;156: 111255. https://doi.org/10.1016/j.marpolbul.2020.111255.

    CAS  Article  Google Scholar 

  40. 40.

    Michels MHA, Vaskoska M, Vermuë MH, Wijffels RH. Growth of Tetraselmis suecica in a tubular photobioreactor on wastewater from a fish farm. Water Res. 2014;65:290–6. https://doi.org/10.1016/j.watres.2014.07.017.

    CAS  Article  PubMed  Google Scholar 

  41. 41.

    Fernández E, Lvarez-Salgado XAÁ, Beiras R, Ovejero A, Méndez G. Coexistence of urban uses and shellfish production in an upwelling-driven, highly productive marine environment: the case of the Ría de Vigo (Galicia, Spain). Reg Stud Marine Sci. 2016;8:362–70. https://doi.org/10.1016/j.rsma.2016.04.002.

    Article  Google Scholar 

  42. 42.

    Keskin T, Abubackar HN, Yazgin O, Gunay B, Azbar N. Effect of percolation frequency on biohydrogen production from fruit and vegetable wastes by dry fermentation. Int J Hydrogen Energy. 2019;44(34):18767–75. https://doi.org/10.1016/j.ijhydene.2018.12.099.

    CAS  Article  Google Scholar 

  43. 43.

    Srivastava RK, Akhtar N, Verma M, Imandi SB. Primary metabolites from overproducing microbial system using sustainable substrates. Biotechnol Appl Biochem. 2020;67(6):852–74. https://doi.org/10.1002/bab.1927.

    CAS  Article  PubMed  Google Scholar 

  44. 44.

    Plazzotta S, Manzocco L, Nicoli MC. Fruit and vegetable waste management and the challenge of fresh-cut salad. Trends Food Sci Technol. 2017;63:51–9. https://doi.org/10.1016/j.tifs.2017.02.013.

    CAS  Article  Google Scholar 

  45. 45.

    Gulhane M, Khardenavis AA, Kari S, Pandit P, Kanade GS, Lokhande S, Vaidya AN, Purohit HJ. Biomethanation of vegetable market waste in an anaerobic baffled reactor: effect of effluent recirculation and carbon mass balance analysis. Bioresour Technol. 2016;215:100–9. https://doi.org/10.1016/j.biortech.2016.04.039.

    CAS  Article  PubMed  Google Scholar 

  46. 46.

    Sales EA, Ghirardi ML, Jorquer O. Subcritical ethylic biodiesel production from wet animal fat and vegetable oils: a net energy ratio analysis. Energy Conver Manag. 2017;141:216–23. https://doi.org/10.1016/j.enconman.2016.08.015.

    CAS  Article  Google Scholar 

  47. 47.

    Collin T, Cunningham R, Jefferson B, Vill R. Characterisation and energy assessment of fats, oils and greases (FOG) waste at catchment level. Waste Manag. 2020;103:399–406. https://doi.org/10.1016/j.wasman.2019.12.040.

    CAS  Article  PubMed  Google Scholar 

  48. 48.

    Hakme E, Lozano A, Ferrer C, Díaz-Galiano FJ, Fernández-Alba AR. Analysis of pesticide residues in olive oil and other vegetable oils. Trends Anal Chem. 2018;100:167–79. https://doi.org/10.1016/j.trac.2017.12.016.

    CAS  Article  Google Scholar 

  49. 49.

    Khouni I, Louhichi G, Ghrabi A, Moulin P. Efficiency of a coagulation/flocculation-membrane filtration hybrid process for the treatment of vegetable oil refinery wastewater for safe reuse and recovery. Proc Safety Environ Protec. 2020;135:323–41. https://doi.org/10.1016/j.psep.2020.01.004.

    CAS  Article  Google Scholar 

  50. 50.

    Schmidt JH. Life cycle assessment of five vegetable oils. J Clean Prod. 2015;87:130–8. https://doi.org/10.1016/j.jclepro.2014.10.011.

    Article  Google Scholar 

  51. 51.

    Kurup GG, Adhikari B, Zisu B. Application of high-frequency ultrasound standing waves for the recovery of lipids from high-fat dairy effluent. Ultrason Sonochem. 2020;63: 104944. https://doi.org/10.1016/j.ultsonch.2019.104944.

    CAS  Article  PubMed  Google Scholar 

  52. 52.

    Stanchev P, Vasilaki V, Egas D, Colon J, Ponsá S, Katsou E. Multilevel environmental assessment of the anaerobic treatment of dairy processing effluents in the context of circular economy. J Clean Prod. 2020;261: 121139. https://doi.org/10.1016/j.jclepro.2020.121139.

    CAS  Article  Google Scholar 

  53. 53.

    Parashar A, Jin Y, Mason B, Chae M, Bressler DC. Incorporation of whey permeate, a dairy effluent, in ethanol fermentation to provide a zero waste solution for the dairy industry. J Dairy Sci. 2016;99(3):1859–67. https://doi.org/10.3168/jds.2015-10059.

    CAS  Article  PubMed  Google Scholar 

  54. 54.

    Sunil S, Prasad BSC, Kotresh M, Kakkeri S. Studies on suitability of multiwalled CNT as catalyst in combustion on a CI engine fueled with dairy waste biodiesel blends. Mater Today Proc. 2020;26:613–9. https://doi.org/10.1016/j.matpr.2019.12.179.

    CAS  Article  Google Scholar 

  55. 55.

    Sahu O. Treatment of sugar processing industry effluent up to remittance limits: suitability of hybrid electrode for electrochemical reactor. Meth X. 2017;4:172–85. https://doi.org/10.1016/j.mex.2017.05.001.

    Article  Google Scholar 

  56. 56.

    Jayabalan T, Matheswaran M, Mohammed SN. Biohydrogen production from sugar industry effluents using nickel-based electrode materials in microbial electrolysis cell. Int J Hydrogen Ener. 2019;44(32):17381–8. https://doi.org/10.1016/j.ijhydene.2018.09.219.

    CAS  Article  Google Scholar 

  57. 57.

    Asaithambi P, Matheswaran M. Electrochemical treatment of simulated sugar industrial effluent: optimization and modeling using a response surface methodology. Arab J Chem. 2016;9:S981–7. https://doi.org/10.1016/j.arabjc.2011.10.004.

    CAS  Article  Google Scholar 

  58. 58.

    Sharma S, Simsek H. Sugar beet industry process wastewater treatment using electrochemical methods and optimization of parameters using response surface methodology. Chemosphere. 2020;238: 124669. https://doi.org/10.1016/j.chemosphere.2019.124669.

    CAS  Article  PubMed  Google Scholar 

  59. 59.

    Huang CL, Xiongm L, Guo H-J, Li H-L, Wang C, Chen X-F, Zhao C, Chen XD. Anaerobic digestion of elephant grass hydrolysate: biogas production, substrate metabolism and outlet effluent treatment. Bioresour Technol. 2019;283:191–7. https://doi.org/10.1016/j.biortech.2019.03.079.

    CAS  Article  PubMed  Google Scholar 

  60. 60.

    Chrispim MC, Scholz M, Nolasco MA. A framework for resource recovery from wastewater treatment plants in megacities of developing countries. Environ Res. 2020;188: 109745. https://doi.org/10.1016/j.envres.2020.109745.

    CAS  Article  PubMed  Google Scholar 

  61. 61.

    Cossio C, Norrman J, Conville JM, Mercado A, Rauch S. Indicators for sustainability assessment of small-scale wastewater treatment plants in low and lower-middle income countries. Environ Sustain Indic. 2020;6: 100028. https://doi.org/10.1016/j.indic.2020.100028.

    Article  Google Scholar 

  62. 62.

    Huijbers PMC, Larsson DGJ, Flach C-F. Surveillance of antibiotic resistant Escherichia coli in human populations through urban wastewater in ten European countries. Environ Pollut. 2020;261: 114200. https://doi.org/10.1016/j.envpol.2020.114200.

    CAS  Article  PubMed  Google Scholar 

  63. 63.

    Rashid SS, Liu Y-Q, Zhang C. Upgrading a large and centralised municipal wastewater treatment plant with sequencing batch reactor technology for integrated nutrient removal and phosphorus recovery: environmental and economic life cycle performance. Sci Total Environ. 2020;749: 141465. https://doi.org/10.1016/j.scitotenv.2020.141465.

    CAS  Article  PubMed  Google Scholar 

  64. 64.

    Yuan Y, Ning X-A, Zhang Y, Lai X, Li D, He Z, Chen X. Chlorobenzene levels, component distribution, and ambient severity in wastewater from five textile dyeing wastewater treatment plants. Ecotoxicol Environ Saf. 2020;193: 110257. https://doi.org/10.1016/j.ecoenv.2020.110257.

    CAS  Article  PubMed  Google Scholar 

  65. 65.

    Arias DM, Solé-Bundó M, Garfí M, Ferrer I, García J, Uggett E. Integrating microalgae tertiary treatment into activated sludge systems for energy and nutrients recovery from wastewater. Bioresour Technol. 2018;247:513–9. https://doi.org/10.1016/j.biortech.2017.09.123.

    CAS  Article  PubMed  Google Scholar 

  66. 66.

    Sun D, Gao Y, Hou D, Zuo K, Chen X, Liang P, Zhang X, Ren ZJ, Huang X. Energy-neutral sustainable nutrient recovery incorporated with the wastewater purification process in an enlarged microbial nutrient recovery cell. J Power Sour. 2018;384:160–4. https://doi.org/10.1016/j.jpowsour.2018.02.049.

    CAS  Article  Google Scholar 

  67. 67.

    Kid K, Ikbal Sonoda Y, Kawase M, Nomura T. Influence of mineral nutrients on high performance during anaerobic treatment of wastewater from a beer brewery. J Ferm Bioeng. 1991;72(1):54–7. https://doi.org/10.1016/0922-338X(91)90146-8.

    Article  Google Scholar 

  68. 68.

    Battista F, Fino D, Mancini G, Ruggeri B. Mixing in digesters used to treat high viscosity substrates: the case of olive oil production wastes. J Environ Chem Eng. 2016;4(1):915–23. https://doi.org/10.1016/j.jece.2015.12.032.

    CAS  Article  Google Scholar 

  69. 69.

    Deaver JA, Diviesti KI, Soni MN, Campbell BJ, Finneran KT, Popat SC. Palmitic acid accumulation limits methane production in anaerobic co-digestion of fats, oils and grease with municipal wastewater sludge. Chem Eng J. 2020;396:12523. https://doi.org/10.1016/j.cej.2020.125235.

    CAS  Article  Google Scholar 

  70. 70.

    Chang Y-IM, Chen J-W, Cheng W-Y, Jang L. The reuse of wastewater in making PVA sponge. J Water Process Eng. 2019;30:100476. https://doi.org/10.1016/j.jwpe.2017.08.014.

    Article  Google Scholar 

  71. 71.

    Deh-Haghi Z, Bagheri A, Fotourehchi Z, Damalas CA. Farmers’ acceptance and willingness to pay for using treated wastewater in crop irrigation: a survey in western Iran. Agric Water Manag. 2020;239: 106262. https://doi.org/10.1016/j.agwat.2020.106262.

    Article  Google Scholar 

  72. 72.

    Liu B, Wang X, Liu Y, Gao Y, Ma Z, Xue J. Simulation analysis of flow velocity and liquid film of saline wastewater in falling film evaporation. Environ Technol Innov. 2020;19: 100790. https://doi.org/10.1016/j.eti.2020.100790.

    Article  Google Scholar 

  73. 73.

    Moschakis T, Biliaderis CG. Biopolymer-based coacervates: structures, functionality and applications in food products. Curr Opin Colloid Interf Sci. 2017;28:96–109. https://doi.org/10.1016/j.cocis.2017.03.006.

    CAS  Article  Google Scholar 

  74. 74.

    Prameela K, Mohan CM, Ramakrishna C. Biopolymers for food design: consumer-friendly natural ingredients. In: Grumezescu AM, Holban AM, editors. Biopolymers for food design handbook of food bioengineering. New York: Academic Press; 2018. p. 1–32. https://doi.org/10.1016/B978-0-12-811449-0.00001-3.

    Chapter  Google Scholar 

  75. 75.

    Wankhade V. Animal-derived biopolymers in food and biomedical technology. In: Pal K, Banerjee I, Sarkar P, Kim D, Deng W-P, Dubey NK, Majumder K, editors. Biopolymer-based formulations biomedical and food applications. New York: Elsevier Inc; 2020. p. 139–52. https://doi.org/10.1016/B978-0-12-816897-4.00006-0.

    Chapter  Google Scholar 

  76. 76.

    Merrylin J, Preethi Saratale GD, Banu JR. Production of biopolymers and feed protein from food wastes. In: Banu JR, Kumar G, Gunasekaran M, Kavitha S, editors. Food waste to valuable resources applications and management. New York: Academic Press; 2020. p. 143–62. https://doi.org/10.1016/B978-0-12-818353-3.00007-9.

    Chapter  Google Scholar 

  77. 77.

    Khademian E, Salehi E, Sanaeepur H, Galiano F, Figoli A. A systematic review on carbohydrate biopolymers for adsorptive remediation of copper ions from aqueous environments-part A: classification and modification strategies. Sci Total Environ. 2020;738: 139829. https://doi.org/10.1016/j.scitotenv.2020.139829.

    CAS  Article  PubMed  Google Scholar 

  78. 78.

    Alipour A, Bahrami A, Saebnoori E. Investigation in effect of different culture medium on the anti-corrosive performance of bacterial biopolymer. J Taiwan Inst Chem Eng. 2017;77:64–72. https://doi.org/10.1016/j.jtice.2017.04.050.

    CAS  Article  Google Scholar 

  79. 79.

    Ng CWW, So PS, Lau SY, Zhou C, Coo JL, Ni JJ. Influence of biopolymer on gas permeability in compacted clay at different densities and water contents. Eng Geol. 2020;272: 105631. https://doi.org/10.1016/j.enggeo.2020.105631.

    Article  Google Scholar 

  80. 80.

    Arun KB, Madhavan A, Sindhu R, Binod P, Pandey A, Reshmy R, Sirohi R. Remodeling agro-industrial and food wastes into value-added bioactives and biopolymers. Ind Crop Product. 2020;154: 112621. https://doi.org/10.1016/j.indcrop.2020.112621.

    CAS  Article  Google Scholar 

  81. 81.

    Vinod A, Sanjay MR, Suchart S, Jyotishkumar P. Renewable and sustainable biobased materials: an assessment on biofibers, biofilms, biopolymers and biocomposites. J Cleaner Prod. 2020;258: 120978. https://doi.org/10.1016/j.jclepro.2020.120978.

    CAS  Article  Google Scholar 

  82. 82.

    Ibrahim S, Saied HE, Hasanin M. Active paper packaging material based on antimicrobial conjugated nano-polymer/amino acid as edible coating. J King Saud Univ Sci. 2019;31(4):1095–102. https://doi.org/10.1016/j.jksus.2018.10.007.

    Article  Google Scholar 

  83. 83.

    Huang X, Zhou D, Wang Y, He C, Zhao W, Sun S, Zhao C. A green approach towards functional hydrogel particles from synthetic polymers via spherical capsule mini-reactors. Chem Eng J. 2019;359:1360–71. https://doi.org/10.1016/j.cej.2018.11.042.

    CAS  Article  Google Scholar 

  84. 84.

    Umaraw P, Munekata PES, Verma AK, Barba FJ, Singh VP, Kumar P, Lorenzo JM. Edible films/coating with tailored properties for active packaging of meat, fish and derived products. Trends Food Sci Technol. 2020;98:10–24. https://doi.org/10.1016/j.tifs.2020.01.032.

    CAS  Article  Google Scholar 

  85. 85.

    Mohanraj R, Gnanamangai BM, Ramesh K, Priya P, Srisunmathi R, Poornima S, Ponmurugan P, Robinson JP. Optimized production of gamma poly glutamic acid (γ-PGA) using sago. Biocatal Agric Biotechnol. 2019;22: 101413. https://doi.org/10.1016/j.bcab.2019.101413.

    Article  Google Scholar 

  86. 86.

    Wang D, Hwang J-S, Kim D-H, Lee S, Kim D-H, Joe M-H. A newly isolated Bacillus siamensis SB1001 for mass production of poly-γ-glutamic acid. Process Biochem. 2020;92:164–73. https://doi.org/10.1016/j.procbio.2019.11.034.

    CAS  Article  Google Scholar 

  87. 87.

    Luo SG, Chen SC, Cao WZ, Lin WH, Sheu YT, Kao CM. Application of γ-PGA as the primary carbon source to bioremediate a TCE-polluted aquifer: a pilot-scale study. Chemosphere. 2019;237: 124449. https://doi.org/10.1016/j.chemosphere.2019.124449.

    CAS  Article  PubMed  Google Scholar 

  88. 88.

    Li J, Luo C, Zhang G, Zhang D. Coupling magnetic-nanoparticle mediated isolation (MMI) and stable isotope probing (SIP) for identifying and isolating the active microbes involved in phenanthrene degradation in wastewater with higher resolution and accuracy. Water Res. 2018;144:226–34. https://doi.org/10.1016/j.watres.2018.07.036.

    CAS  Article  PubMed  Google Scholar 

  89. 89.

    Saharan BS, Grewal A, Kumar P. Biotechnological production of polyhydroxyalkanoates: a review on trends and latest developments. Chin J Biol. 2014;2014: 802984. https://doi.org/10.1155/2014/802984.

    Article  Google Scholar 

  90. 90.

    Birch J, Calsteren MRV, Pérez S, Svensson B. The exopolysaccharide properties and structures database: EPS-DB. Application to bacterial exopolysaccharides. Carbohydr Polym. 2019;205:565–657. https://doi.org/10.1016/j.carbpol.2018.10.063.

    CAS  Article  PubMed  Google Scholar 

  91. 91.

    Wei J, Wang B, Li Z, Wu Z, Zhang M, Sheng N, Liang Q, Wang H, Chen S. A 3D-printable TEMPO-oxidized bacterial cellulose/alginate hydrogel with enhanced stability via nanoclay incorporation. Carbohydr Polym. 2020;238: 116207. https://doi.org/10.1016/j.carbpol.2020.116207.

    CAS  Article  PubMed  Google Scholar 

  92. 92.

    Reddy MV, Watanabe A, Onodera R, Mawatari Y, Tsukiori Y, Watanabe A, Kudou M, Chang Y-C. Polyhydroxyalkanoates (PHA) production using single or mixture of fatty acids with Bacillus sp. CYR1: Identification of PHA synthesis genes. Bioresour Technol Rep. 2020;11: 100483. https://doi.org/10.1016/j.biteb.2020.100483.

    Article  Google Scholar 

  93. 93.

    Li B, Boiarkina I, Yu W, Huang HM, Munir T, Wang GQ, Young BR. Phosphorous recovery through struvite crystallization: challenges for future design. Sci Total Environ. 2019;648:12441256.

    Google Scholar 

  94. 94.

    Natsir MF, Ainkhaer MS. The effectiveness of drum of wastewater treatment (DOWT) in reducing TSS of domestic wastewater. Enferm Clínic. 2020;30:175–7. https://doi.org/10.1016/j.enfcli.2019.10.063.

    Article  Google Scholar 

  95. 95.

    Ahmadi F, Zinatizadeh AA, Asadi A. The effect of different operational strategies on polyhydroxyalkanoates (PHAs) production at short-term biomass enrichment. J Environ Chem Eng. 2020;8(3): 103531. https://doi.org/10.1016/j.jece.2019.103531.

    CAS  Article  Google Scholar 

  96. 96.

    Gu J-N, Liang J, Chen C, Li K, Zhou W, Jia J, Sun T. Treatment of real deplating wastewater through an environmental friendly precipitation-electrodeposition-oxidation process: Recovery of silver and copper and reuse of wastewater. Sep Purif Technol. 2020;248: 117082. https://doi.org/10.1016/j.seppur.2020.117082.

    CAS  Article  Google Scholar 

  97. 97.

    Fang F, Xu R-Z, Huang Y-Q, Wang S-N, Zhang L-L, Dong JY, Xie W-M, Chen X, Cao J-S. Production of polyhydroxyalkanoates and enrichment of associated microbes in bioreactors fed with rice winery wastewater at various organic loading rates. Bioresour Technol. 2019;292: 121978. https://doi.org/10.1016/j.biortech.2019.121978.

    CAS  Article  PubMed  Google Scholar 

  98. 98.

    Chojnacka K, Witek-Krowiak A, Moustakas K, Skrzypczak D, Mikula K, Loizidou M. A transition from conventional irrigation to fertigation with reclaimed wastewater: prospects and challenges. Renew Sustain Energy Rev. 2020;130: 109959. https://doi.org/10.1016/j.rser.2020.109959.

    CAS  Article  Google Scholar 

  99. 99.

    Bengtsson S, Karlsson A, Alexandersson T, Quadri L, Hjort M, Johansson P, Morgan-Sagastume F, Anterrieu S, Arcos-Hernandez M, Karabegovic L, Magnusson P, Werker A. A process for polyhydroxyalkanoate (PHA) production from municipal wastewater treatment with biological carbon and nitrogen removal demonstrated at pilot-scale. New Biotechnol. 2017;35:42–53. https://doi.org/10.1016/j.nbt.2016.11.005.

    CAS  Article  Google Scholar 

  100. 100.

    Xia J, Sun H, Ma X, Huang K, Ye L. Ozone pretreatment of wastewater containing aromatics reduces antibiotic resistance genes in bioreactors: the example of p-aminophenol. Environ Int. 2020;142: 105864. https://doi.org/10.1016/j.envint.2020.105864.

    CAS  Article  PubMed  Google Scholar 

  101. 101.

    Adeleye AT, Odoh CK, Enudi OC, Banjoko OO, Osiboye OO, Odedirane ET, Louis H. Sustainable synthesis and applications of polyhydroxyalkanoates (PHAs) from biomass. Proc Biochem. 2020;96:174–93. https://doi.org/10.1016/j.procbio.2020.05.032.

    CAS  Article  Google Scholar 

  102. 102.

    Morgan-Sagastume F, Heimersson S, Laera G, Werkera A, Svanström M. Techno-environmental assessment of integrating polyhydroxyalkanoate (PHA) production with services of municipal wastewater treatment. J Clean Prod. 2016;137:1368–81. https://doi.org/10.1016/j.jclepro.2016.08.008.

    CAS  Article  Google Scholar 

  103. 103.

    Tu W, Zou Y, Wu M, Wang H. Reducing the effect of non-volatile fatty acids (non-VFAs) on polyhydroxyalkanoates (PHA) production from fermented thermal-hydrolyzed sludge. Int J Biol Macromol. 2020;155:1317–24. https://doi.org/10.1016/j.ijbiomac.2019.11.103.

    CAS  Article  PubMed  Google Scholar 

  104. 104.

    Morgan-Sagastume F, Hjort M, Cirne D, Gérardin F, Lacroix S, Gaval G, Karabegovic L, Alexandersson T, Johansson P, Karlsson A, Bengtsson S, Arcos-Hernánde MV, Magnusson P, Werker A. Integrated production of polyhydroxyalkanoates (PHAs) with municipal wastewater and sludge treatment at pilot scale. Bioresour Technol. 2015;181:78–89. https://doi.org/10.1016/j.biortech.2015.01.046.

    CAS  Article  PubMed  Google Scholar 

  105. 105.

    Zhao F, He F, Liu X, Shi J, Liang J, Wang S, Yang C, Liu R. Metabolic engineering of Pseudomonas mendocina NK-01 for enhanced production of medium-chain-length polyhydroxyalkanoates with enriched content of the dominant monomer. Int J Biol Macromol. 2020;154:1596–605. https://doi.org/10.1016/j.ijbiomac.2019.11.044.

    CAS  Article  PubMed  Google Scholar 

  106. 106.

    Tamis J, Lužkov K, Jiang Y, von Loosdrecht MCM, Kleerebezem R. Enrichment of Plasticicumulans acidivorans at pilot-scale for PHA production on industrial wastewater. J Biotechnol. 2014;192:161–9. https://doi.org/10.1016/j.jbiotec.2014.10.022.

    CAS  Article  Google Scholar 

  107. 107.

    Barros ARM, Rollemberg SLDS, Carvalho CDA, Moura HHI, Firmino PIM, Santos AB. Effect of calcium addition on the formation and maintenance of aerobic granular sludge (AGS) in simultaneous fill/draw mode sequencing batch reactors (SBRs). J Environ Manag. 2020;255: 109850. https://doi.org/10.1016/j.jenvman.2019.109850.

    CAS  Article  Google Scholar 

  108. 108.

    Ahmadi F, Zinatizadeh AA, Asadi A, McKay T, Azizi S. Simultaneous carbon and nutrients removal and PHA production in a novel single air lift bioreactor treating an industrial wastewater. Environ Technol Innov. 2020;18: 100776. https://doi.org/10.1016/j.eti.2020.100776.

    Article  Google Scholar 

  109. 109.

    Ji G, Zhai F, Wang R, Ni J. Sludge granulation and performance of a low superficial gas velocity sequencing batch reactor (SBR) in the treatment of prepared sanitary wastewater. Bioresour Technol. 2010;101(23):9058–64. https://doi.org/10.1016/j.biortech.2010.07.045.

    CAS  Article  PubMed  Google Scholar 

  110. 110.

    Argiz L, Fra-Vázquez A, del Río ÁV, Mosquera-Corral A. Optimization of an enriched mixed culture to increase PHA accumulation using industrial saline complex wastewater as a substrate. Chemosphere. 2020;247: 125873. https://doi.org/10.1016/j.chemosphere.2020.125873.

    CAS  Article  PubMed  Google Scholar 

  111. 111.

    Masłoń A, Tomaszek JA, Zamorska J, Zdeb M, Piech A, Opaliński I, Jurczyk Ł. The impact of powdered keramsite on activated sludge and wastewater treatment in a sequencing batch reactor. J Environ Manag. 2019;237:305–12. https://doi.org/10.1016/j.jenvman.2019.02.035.

    CAS  Article  Google Scholar 

  112. 112.

    Reddy MV, Mohan SV. Effect of substrate load and nutrients concentration on the polyhydroxyalkanoates (PHA) production using mixed consortia through wastewater treatment. Bioresour Technol. 2012;114:573–82. https://doi.org/10.1016/j.biortech.2012.02.

    Article  Google Scholar 

  113. 113.

    Wang X, Majzoobi M, Farahnaky A. Ultrasound-assisted modification of functional properties and biological activity of biopolymers: a review. Ultrason Sonochem. 2020;65: 105057. https://doi.org/10.1016/j.ultsonch.2020.105057.

    CAS  Article  PubMed  Google Scholar 

  114. 114.

    Li D, Zhang S, Li S, Zeng H, Zhang J. Aerobic granular sludge operation and nutrients removal mechanism in a novel configuration reactor combined sequencing batch reactor and continuous-flow reactor. Bioresour Technol. 2019;292: 122024. https://doi.org/10.1016/j.biortech.2019.122024.

    CAS  Article  PubMed  Google Scholar 

  115. 115.

    Bhalerao A, Banerjee R, Nogueira R. Continuous cultivation strategy for yeast industrial wastewater-based polyhydroxyalkanoate production. J Biosci Bioeng. 2020;129(5):595–602. https://doi.org/10.1016/j.jbiosc.2019.11.006.

    CAS  Article  PubMed  Google Scholar 

  116. 116.

    Zhang Y, Kuroda M, Nakatani Y, Soda S, Ike M. Removal of selenite from artificial wastewater with high salinity by activated sludge in aerobic sequencing batch reactors. J Biosci Bioeng. 2019;127(5):618–24. https://doi.org/10.1016/j.jbiosc.2018.11.002.

    CAS  Article  PubMed  Google Scholar 

  117. 117.

    Mannina G, Presti D, Montiel-Jarillo G, Carrera J, Suárez-Ojeda ME. Recovery of polyhydroxyalkanoates (PHAs) from wastewater: a review. Bioresour Technol. 2020;297: 122478. https://doi.org/10.1016/j.biortech.2019.122478.

    CAS  Article  PubMed  Google Scholar 

  118. 118.

    Mehta CM, Khunjar WO, Nguyen V, Tait S, Batstone DJ. Technologies to recover nutrients from waste streams: a critical review. Crit Rev Environ Sci Technol. 2015;45(4):385–427. https://doi.org/10.1080/10643389.2013.866621.

    Article  Google Scholar 

  119. 119.

    Yan T, Ye Y, Ma H, Zhang Y, Guo W, Du B, Wei Q, Wei D, Ngo HH. A critical review on membrane hybrid system for nutrient recovery from wastewater. Chem Eng J. 2018; 348:143–156. http://hdl.handle.net/10453/124511

  120. 120.

    Robles Á, Aguado D, Barat R, Borrás L, Bouzas A, Giménez JB, Martí N, Ribes J, Ruano MV, Serralta J, Ferrer J, Seco A. New frontiers from removal to recycling of nitrogen and phosphorus from wastewater in the circular economy. Bioresour Technol. 2020;300: 122673. https://doi.org/10.1016/j.biortech.2019.122673.

    CAS  Article  PubMed  Google Scholar 

  121. 121.

    Singh N, Dhiman S, Basu S, Balakrishnan M, Petrinic I, Helix-Nielsen C. Dewatering of sewage for nutrients and water recovery by Forward Osmosis (FO) using divalent draw solution. J Water Process Eng. 2019;31: 100853. https://doi.org/10.1016/J.JWPE.2019.100853.

    Article  Google Scholar 

  122. 122.

    Peng L, Dai H, Wu Y, Peng Y, Lu X. A comprehensive review of phosphorus recovery from wastewater by crystallization processes. Chemosphere. 2018;197:768–81. https://doi.org/10.1016/j.chemosphere.2018.01.098.

    CAS  Article  PubMed  Google Scholar 

  123. 123.

    Salehi S, Cheng KY, Heitz A, Ginige MP. Re-visiting the Phostrip process to recover phosphorus from municipal wastewater. Chem Eng J. 2018;343:390–8. https://doi.org/10.1016/J.CEJ.2018.02.074.

    CAS  Article  Google Scholar 

  124. 124.

    Romero-Villegas GI, Fiamengo M, Acien-Fernandez FG, Molina-Grima E. Utilization of centrate for the outdoor production of marine microalgae at the pilotscale in raceway photobioreactors. J Environ Manage. 2018;228:506–16.

    CAS  Article  Google Scholar 

  125. 125.

    Vo HNP, Ngo HH, Guo W, Nguyen TMH, Yiwen L, Yi L, Nguyen DD, Chang SW. A critical review on designs and applications of microalgae-based photobioreactors for pollutants treatment. Sci Total Environ. 2019;651:1549–68. https://doi.org/10.1016/j.scitotenv.2018.09.282.

    CAS  Article  PubMed  Google Scholar 

  126. 126.

    Fernandez FGA, Gomez-Serrano C, Fernandez-Sevilla JM. Recovery of nutrients from wastewaters using microalgae. Front Sustain Food Syst. 2018;2:1–13. https://doi.org/10.3389/fsufs.2018.00059.

    Article  Google Scholar 

  127. 127.

    Guldhe A, Kumari S, Ramanna L, Ramsundar P, Singh P, Rawat I, Bux F. Prospects, recent advancements and challenges of different wastewater streams for microalgal cultivation. J Environ Manag. 2017;203:299–315. https://doi.org/10.1016/j.jenvman.2017.08.012.

    CAS  Article  Google Scholar 

  128. 128.

    Garrido-Cardenas JA, Manzano-Agugliaro F, Acien-Fernandez FG, Molina-Grima E. Microalgae research worldwide. Algal Res. 2018;35:50–60. https://doi.org/10.1016/j.algal.2018.08.005.

    Article  Google Scholar 

  129. 129.

    Marazzi F, Bellucci M, Rossi S, Fornaroli R, Ficara E, Mezzanotte V. Outdoor pilot trial integrating a sidestream microalgae process for the treatment of centrate under non optimal climate conditions. Algal Res. 2019;39: 101430. https://doi.org/10.1016/j.algal.2019.101430.

    Article  Google Scholar 

  130. 130.

    Hulsen T, Batstone DJ, Keller J. Phototrophic bacteria for nutrient recovery from domestic wastewater. Water Res. 2014;50:18–26. https://doi.org/10.1016/j.watres.2013.10.051.

    CAS  Article  PubMed  Google Scholar 

  131. 131.

    Gonzalez E, Diaz O, Ruigomez I, de Vera CR, Rodriguez-Gomez LE, Rodriguez-Sevilla J, Vera L. Photosynthetic bacteria-based membrane bioreactor as post-treatment of an anaerobic membrane bioreactor effluent. Bioresour Technol. 2017;239:528–32. https://doi.org/10.1016/j.biortech.2017.05.042.

    CAS  Article  PubMed  Google Scholar 

  132. 132.

    Nie J, Sun Y, Zhou Y, Kumar M, Usman M, Li J, Shao J, Wang L, Tsang DCW. Bioremediation of water containing pesticides by microalgae: mechanisms, methods, and prospects for future research. Sci Total Environ. 2020;707: 136080. https://doi.org/10.1016/j.scitotenv.2019.136080.

    CAS  Article  PubMed  Google Scholar 

  133. 133.

    Kumar M, Sun Y, Rathour R, Pandey A, Thakur IS, Tsang DCW. Algae as potential feedstock for the production of biofuels and value-added products: opportunities and challenges. Sci Total Environ. 2020;716: 137116. https://doi.org/10.1016/j.scitotenv.2020.137116.

    CAS  Article  PubMed  Google Scholar 

  134. 134.

    Cui J, Li F, Wang Y, Zhang Q, Ma W, Huang C. Electrospun nanofiber membranes for wastewater treatment applications. Sep Purif Technol. 2020;250: 117116. https://doi.org/10.1016/j.seppur.2020.117116.

    CAS  Article  Google Scholar 

  135. 135.

    Kotoula D, Iliopoulou A, Irakleous-Palaiologou E, Gatidou G, Aloupi M, Antonopoulou P, Fountoulakis MS, Stasinakis AS. Municipal wastewater treatment by combining in series microalgae Chlorella sorokiniana and macrophyte Lemna minor: preliminary results. J Clean Prod. 2020;271: 122704. https://doi.org/10.1016/j.jclepro.2020.122704.

    CAS  Article  Google Scholar 

  136. 136.

    Hanum F, Yuan LC, Kamahara H, Aziz HA, Atsuta Y, Yamada T, Daimon H. Treatment of sewage sludge using anaerobic digestion in Malaysia: current state and challenges. Front Energy Res. 2019;7:19. https://doi.org/10.3389/fenrg.2019.00019.

    Article  Google Scholar 

  137. 137.

    Perera MK, Englehardt JD. Simultaneous nitrogen and phosphorus recovery from municipal wastewater by electrochemical pH modulation. Sep Purif Technol. 2020;250: 117166. https://doi.org/10.1016/j.seppur.2020.117166.

    CAS  Article  Google Scholar 

  138. 138.

    Ullah A, Hussain S, Wasim A, Jahanzaib M. Development of a decision support system for the selection of wastewater treatment technologies. Sci Total Environ. 2020;731: 139158. https://doi.org/10.1016/j.scitotenv.2020.139158.

    CAS  Article  PubMed  Google Scholar 

  139. 139.

    Tahreen A, Jami MS, Ali F. Role of electrocoagulation in wastewater treatment: a developmental review. J Water Process Eng. 2020;37: 101440. https://doi.org/10.1016/j.jwpe.2020.101440.

    Article  Google Scholar 

  140. 140.

    Mukimin A, Zen N, Purwanto A, Wicaksono KA, Vistanty H, Alfauzi AS. Application of a full-scale electrocatalytic reactor as real batik printing wastewater treatment by indirect oxidation process. J Environ Chem Eng. 2017;5(5):5222–32. https://doi.org/10.1016/j.jece.2017.09.053.

    CAS  Article  Google Scholar 

  141. 141.

    Golshan M, Jorfi S, Haghighifard NJ, Takdastan A, Ghafari S, Rostami S, Ahmadi M. Development of salt-tolerant microbial consortium during the treatment of saline bisphenol A-containing wastewater: Removal mechanisms and microbial characterization. J Water Process Eng. 2019;32: 100949. https://doi.org/10.1016/j.jwpe.2019.100949.

    Article  Google Scholar 

  142. 142.

    Simona C, Raluca I, Anita-Laura R, Andrei S, Raluca S, Bogdan T, Elvira A, Catalin-Ilie S, Claudiu FR, Daniela I-E, Silviu P, Leonard-Ionut A, Dan D. Synthesis, characterization and efficiency of new organically modified montmorillonite polyethersulfone membranes for removal of zinc ions from wastewasters. Appl Clay Sci. 2017;137:135–42. https://doi.org/10.1016/j.clay.2016.12.013.

    CAS  Article  Google Scholar 

  143. 143.

    Bhattachary A, Mathur M, Kumar P, Prajapati SK, Malik A. A rapid method for fungal assisted algal flocculation: critical parameters & mechanism insights. Algal Res. 2017;21:42–51. https://doi.org/10.1016/j.algal.2016.10.022.

    Article  Google Scholar 

  144. 144.

    Schambeck CM, Girbal-Neuhauser E, Böni L, Fischer P, Bessière Y, Paul E, Costa RHR, Derlon N. Chemical and physical properties of alginate-like exopolymers of aerobic granules and flocs produced from different wastewaters. Bioresour Technol. 2020;312: 123632. https://doi.org/10.1016/j.biortech.2020.123632.

    CAS  Article  PubMed  Google Scholar 

  145. 145.

    Schambeck CM, Magnus BS, de Souza LCR, Leite WRM, Derlon N, Guimarães LB, da Costa RHR. Biopolymers recovery: dynamics and characterization of alginate-like exopolymers in an aerobic granular sludge system treating municipal wastewater without sludge inoculums. J Environ Manag. 2020;263: 110394. https://doi.org/10.1016/j.jenvman.2020.110394.

    CAS  Article  Google Scholar 

  146. 146.

    Donner MW, Arshad M, Ullah A, Siddique T. Unravelled keratin-derived biopolymers as novel biosorbents for the simultaneous removal of multiple trace metals from industrial wastewater. Sci Total Environ. 2019;647:1539–46. https://doi.org/10.1016/j.scitotenv.2018.08.085.

    CAS  Article  PubMed  Google Scholar 

  147. 147.

    Sarioglu OF, Keskin NOS, Celebioglu A, Tekinay T, Uyar T. Bacteria immobilized electrospun polycaprolactone and polylactic acid fibrous webs for remediation of textile dyes in water. Chemosphere. 2017;184:393–9. https://doi.org/10.1016/j.chemosphere.2017.06.020.

    CAS  Article  PubMed  Google Scholar 

  148. 148.

    Dinesh GH, Nguyen DD, Ravindran B, Chang SW, Vo D-VN, Bach Q-V, Tran HN, Basu MJ, Mohanrasu K, Murugan RS, Swetha TA, Sivapraksha G, Selvaraj A, Arun A. Simultaneous biohydrogen (H2) and bioplastic (poly-β-hydroxybutyrate-PHB) productions under dark, photo, and subsequent dark and photo fermentation utilizing various wastes. Int J Hydrogen Energy. 2020;45(10):5840–53. https://doi.org/10.1016/j.ijhydene.2019.09.036.

    CAS  Article  Google Scholar 

  149. 149.

    Reddy MV, Mawatari Y, Onoder R, Nakamur Y, Yajim Y, Chang Y-C. Bacterial conversion of waste into polyhydroxybutyrate (PHB): a new approach of bio-circular economy for treating waste and energy generation. Bioresour Technol Rep. 2019;7: 100246. https://doi.org/10.1016/j.biteb.2019.100246.

    Article  Google Scholar 

  150. 150.

    Krasaesue N, Incharoensakdi A, Khetkorn W. Utilization of shrimp wastewater for poly-β-hydroxybutyrate production by Synechocystis sp. PCC 6803 strain ΔSphU cultivated in photobioreactor. Biotechnol Rep. 2019;23: e00345. https://doi.org/10.1016/j.btre.2019.e00345.

    Article  Google Scholar 

  151. 151.

    Peña-Jurado E, Pérez-Vega S, de la Serna FJZD, Pérez-Reyes I, Gutiérrez-Méndez N, Vazquez-Castillo J, Salmerón I. Production of poly (3-hydroxybutyrate) from a dairy industry wastewater using Bacillus subtilis EPAH18: bioprocess development and simulation. Biochem Eng J. 2019;151: 107324. https://doi.org/10.1016/j.bej.2019.107324.

    CAS  Article  Google Scholar 

  152. 152.

    Namboodiri MMT, Pakshirajan K. Sustainable and green approach of chitosan production from Penicillium citrinum biomass using industrial wastewater as a cheap substrate. J Environ Manag. 2019;240:431–40. https://doi.org/10.1016/j.jenvman.2019.03.085.

    CAS  Article  Google Scholar 

  153. 153.

    Turunen J, Karppinen A, Ihme R. Effectiveness of biopolymer coagulants in agricultural wastewater treatment at two contrasting levels of pollution. SN Appl Sci. 2019;1:210. https://doi.org/10.1007/s42452-019-0225-x.

    CAS  Article  Google Scholar 

  154. 154.

    Coltelli M-B, Cinelli P, Gigante V, Aliotta L, Morganti P, Panariello L, Lazzeri A. Chitin nanofibrils in poly(lactic acid) (PLA) nanocomposites: dispersion and thermo-mechanical properties. Int J Mol Sci. 2019;20:504. https://doi.org/10.3390/ijms20030504.

    CAS  Article  PubMed Central  Google Scholar 

  155. 155.

    Righetti MC, Cinelli P, Mallegni N, Massa CA, Bronco S, Stäbler A, Lazzeri A. Thermal, mechanical, and rheological properties of biocomposites made of poly(lactic acid) and potato pulp powder. Int J Mol Sci. 2019;20:675. https://doi.org/10.3390/ijms20030675.

    CAS  Article  PubMed Central  Google Scholar 

  156. 156.

    Grujic R, Vukic M, Gojkovic V, et al. Application of biopolymers in the food industry. In: Pellicer E, et al., editors. Advances in applications of industrial biomaterials. Cham: Springer; 2017. p. 103–19. https://doi.org/10.1007/978-3-319-62767-0_6.

    Chapter  Google Scholar 

  157. 157.

    Aldana DS, Andrade-Ochoa S, Aguilar CN, Aguilar CN, Contreras-Esquivel JC, Nevárez-Moorillón GV. Antibacterial activity of pectic-based edible films incorporated with Mexican lime essential oil. Food Contr. 2015;50:907–12. https://doi.org/10.1016/j.foodcont.2014.10.044.

    CAS  Article  Google Scholar 

  158. 158.

    Ali A, Mohd N, Maysoun N, Mustafa A. Antimicrobial activity of chitosan enriched with lemongrass oil against anthracnose of bell pepper. Food Pack Shelf Lif. 2015;3:56–61. https://doi.org/10.1016/j.fpsl.2014.10.003.

    Article  Google Scholar 

  159. 159.

    Cai L, Li J, Quan S, Feng W, Yao J, Yang M, Li W. Dextran-based hydrogel with enhanced mechanical performance via covalent and non-covalent cross-linking units carrying adipose-derived stem cells toward vascularized bone tissue engineering. J Mater Res. 2019;07(6):1120–31. https://doi.org/10.1002/jbm.a.36580.

    CAS  Article  Google Scholar 

  160. 160.

    Sun G, Mao JJ. Engineering dextran-based scaffolds for drug delivery and tissue repair. Nanomedicine (Lond). 2012;7(11):1771–84. https://doi.org/10.2217/nnm.12.149.

    CAS  Article  Google Scholar 

  161. 161.

    Jaiswal L, Shankar S, Rhim J-W, Hahm D-H. Lignin-mediated green synthesis of AgNPs in carrageenan matrix for wound dressing applications. Int J Biol Macromol. 2020;159:859–69. https://doi.org/10.1016/j.ijbiomac.2020.05.145.

    CAS  Article  PubMed  Google Scholar 

  162. 162.

    Agostinho DAS, Paninho AI, Cordeiro T, Nunes AVM, Fonseca IM, Pereira C, Matias A, Ventura MG. Properties of κ-carrageenan aerogels prepared by using different dissolution media and its application as drug delivery systems. Mater Chem Phys. 2020;253: 123290. https://doi.org/10.1016/j.matchemphys.2020.123290.

    CAS  Article  Google Scholar 

  163. 163.

    Fernando IPS, Lee WW, Han EJ, Ahn G. Alginate-based nanomaterials: fabrication techniques, properties, and applications. Chem Eng J. 2020;391:12382. https://doi.org/10.1016/j.2019.123823.

    Article  Google Scholar 

  164. 164.

    Tsioptsias C, Lionta G, Deligiannis A, Samaras P. Enhancement of the performance of a combined microalgae-activated sludge system for the treatment of high strength molasses wastewater. J Environ Manag. 2016;183(1):126–32. https://doi.org/10.1016/j.jenvman.2016.08.067.

    CAS  Article  Google Scholar 

  165. 165.

    Baharvand S, Daneshvar MRM. Impact assessment of treating wastewater on the physiochemical variables of environment: a case of Kermanshah wastewater treatment plant in Iran. Environ Syst Res. 2019;8:18. https://doi.org/10.1186/s40068-019-0146-0.

    Article  Google Scholar 

  166. 166.

    Molazadeh M, Ahmadzadeh H, Pourianfar HR, Lyon S, Rampelotto PH. The use of microalgae for coupling wastewater treatment with CO2 biofixation. Front Bioeng Biotechnol. 2019;7:42. https://doi.org/10.3389/fbioe.2019.00042.

    Article  PubMed  PubMed Central  Google Scholar 

  167. 167.

    Ndao A, Sellamuthu B, Kumar LR, Tyagi RD, Valéro JR. Biopesticide production using Bacillus thuringiensis kurstaki by valorization of starch industry wastewater and effluent from aerobic, anaerobic digestion. Syst Microbiol Biomanuf. 2021. https://doi.org/10.1007/s43393-021-00043-x.

    Article  Google Scholar 

  168. 168.

    Kumar LR, Ndao A, Valéro J, Tyagi RD. Production of Bacillus thuringiensis based biopesticide formulation using starch industry wastewater (SIW) as substrate: a techno-economic evaluation. Biores technol. 2019;294: 122144. https://doi.org/10.1016/j.biortech.2019.122144.

    CAS  Article  Google Scholar 

  169. 169.

    Bolognesi S, Bernardi G, Callegari A, Dondi D, Capodaglio AG. Biochar production from sewage sludge and microalgae mixtures: properties, sustainability and possible role in circular economy. Biomass Conv Bioref. 2021;11:289–99. https://doi.org/10.1007/s13399-019-00572-.

    CAS  Article  Google Scholar 

  170. 170.

    Racek J, Sevcik J, Komendova R, Kucerik J, Hlavinek P. Heavy metal fixation in biochar after microwave pyrolysis of sewage sludge. Desalin Water Treat. 2019;159:79–92. https://doi.org/10.5004/dwt.2019.24282.

    CAS  Article  Google Scholar 

  171. 171.

    Tian Y, Cui L, Lin Q, Li G, Zhao X. The sewage sludge biochar at low pyrolysis temperature had better improvement in urban soiland turf grass. Agronomy. 2019;9:156. https://doi.org/10.3390/agronomy9030156.

    CAS  Article  Google Scholar 

  172. 172.

    Demirbas A, Taylan O, Kaya D. Biogas production from municipal sewage sludge (MSS). Energy Sourc Recov Utiliz Environ Effect. 2016;38(20):3027–33. https://doi.org/10.1080/15567036.2015.1124944.

    CAS  Article  Google Scholar 

  173. 173.

    Zhen G, Lu X, Kato H, ZhaoY LYY. Overview of pretreatment strategies for enhancing sewage sludge disintegration and subsequent anaerobic digestion: current advances, full-scale application and future perspectives. Renew Sustain Energy Rev. 2017;69:559–77. https://doi.org/10.1016/j.rser.2016.11.187.

    CAS  Article  Google Scholar 

Download references

Acknowledgements

RKS acknowledges the kind supports provided by his employer the Gitam Institute of Technology & Management GITAM. CPS and TS thank the ERASMUS+ International Masters of Science in Environmental Technology and Engineering (IMETE), jointly offered by Ghent University (Belgium), IHE Delft Institute for Water Education (The Netherlands), and the University of Chemistry and Technology, Prague (Czech Republic) for providing funding to pursue the MSc programme. ERR thanks the Environmental Science (ES) programme at IHE Delft for providing staff time support (Project: “Support to Society”) to collaborate with researchers from India. The authors thank their respective institutes in India and the Netherlands for providing infrastructural support to start this collaborative research on “waste to energy and biomaterials”.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Eldon R. Rene.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Srivastava, R.K., Pothu, R., Sanchez, C.P. et al. Removal and recovery of nutrients and value-added products from wastewater: technological options and practical perspective. Syst Microbiol and Biomanuf (2021). https://doi.org/10.1007/s43393-021-00056-6

Download citation

Keywords

  • Biopolymers
  • Nutrient resources
  • Value-added products
  • Resource recovery
  • Wastewater