Sustainable treatment of different high-strength cheese whey wastewaters: an innovative approach for atmospheric CO2 mitigation and fertilizer production
- 305 Downloads
Raw cheese whey wastewater (CWW) has been treated by means of FeCl3 coagulation-flocculation, NaOH precipitation, and Ca(OH)2 precipitation. Three different types of CWW were considered: without cheese whey recovery (CWW0), 60 % cheese whey recovery (CWW60), and 80 % cheese whey recovery (CWW80). Cheese whey recovery significantly influenced the characteristics of the wastewater to be treated: organic matter, solids, turbidity, conductivity, sodium, chloride, calcium, nitrogen, potassium, and phosphorus. Initial organic load was reduced to values in the interval of 60–70 %. Application of FeCl3, NaOH, or Ca(OH)2 involved additional chemical oxygen demand (COD) depletions regardless of the CWW used. Under optimum conditions, the combination of 80 % cheese whey recovery and lime application led to 90 % reduction in COD. Turbidity (99.8%), total suspended solids (TSS) (98–99 %), oils and fats (82–96 %), phosphorus (98–99 %), potassium (96–97 %), and total coliforms (100 %) were also reduced. Sludge generated in the latter process showed excellent settling properties. This solid after filtration and natural evaporation can be used as fertilizer with limitations due to its saline nature. In an innovative, low-cost, and environmentally friendly technology, supernatant coming from the Ca(OH)2 addition was naturally neutralized in 4–6 days by atmospheric CO2 absorption without reagent addition. Consequently, a final aerobic biodegradation step can be applied for effluent polishing. This technology also allows for some atmospheric CO2 mitigation. Time requirement for the natural carbonation depends on the effluent characteristics. A precipitate rich in organic matter and nutrients and depletions of solids, sodium, phosphorus, magnesium, Kjeldahl, and ammoniacal nitrogen were also achieved during the natural carbonation.
KeywordsCheese whey recovery Biodegradability Physicochemical processes Atmospheric CO2 mitigation Sludge characterization Sludge filterability
The authors thank the economic support received from the Research Group TRATAGUAS (Spain) and Fundação para a Ciência e a Tecnologia (grant SFRH/BD/47559/2008), Portugal under the QREN–POPH with co-participation of the Fundo Social Europeu and national funds. The financial support of the Laboratory of Water Quality Control (IPBeja—Portugal) and cheese whey wastewater from the Queijaria Guilherme are also acknowledged.
- http://pac.iupac.org/publications/pac/pdf/1965/pdf/1004x0625.pdf. Accessed 24 September 2012
- Martins RC, Quinta-Ferreira RM (2010) Final remediation of post-biological treated milk whey wastewater by ozone. Int J Chem React Eng 8(1):Article A142Google Scholar
- Martins RC, Rossi AF, Castro-Silva S, Quinta-Ferreira RM (2010) Fenton’s process for post-biologically treated cheese production wastewaters final remediation. toxicity assessment. Int J Chem React Eng 8(1):Article A84Google Scholar
- Metcalf and Eddy (2003) Wastewater engineering, treatment and reuse, 4th Ed. McGraw-Hill, New York, United StatesGoogle Scholar
- Pan S-Y, Chang EE, Chiang P-C (2012) CO2 capture by accelerated carbonation of alkaline wastes: a review on its principles and applications. Aerosol Air Qual Res 12(5):770–791Google Scholar
- Prazeres AR, Carvalho F, Rivas J (2013b) Fenton-like application to pretreated cheese whey wastewater. J Environ Manage 129:199–205Google Scholar
- Prazeres AR, Carvalho F, Rivas J, Patanita M, Dôres J (2013a) Growth and development of tomato plants Lycopersicon Esculentum Mill. under different saline conditions by fertirrigation with pretreated cheese whey wastewater. Water Sci Technol 67 (9):2033–2041Google Scholar
- Prazeres AR, Carvalho F, Rivas J, Patanita M, Dôres J (2013c) Pretreated cheese whey wastewater management by agricultural reuse: chemical characterization and response of tomato plants Lycopersicon esculentum Mill. under salinity conditions. Sci Total Environ 463–464:943–951Google Scholar
- Ramalho RS (1996) Tratamiento de aguas residuales, Edición revisada - Editorial Reverté, S.A., Barcelona, EspañaGoogle Scholar
- Robbins CW, Lehrsch GA (1998) Cheese whey as a soil conditioner. In: Wallace A, Terry RE (eds) Handbook of soil conditioners: substances that enhance the physical properties of soil. Marcel Dekker Inc, New York, United States of America, pp 167–186Google Scholar