Approaches to Agro-industrial Solid Waste Disposal and Bioenergy Generation

Abstract

Increasing concern about the environment, food and feed shortages, and hike in the price of petroleum has stimulated interest in the new ways of producing more bioenergy. The interest is rapidly increasing toward converting agricultural and industrial wastes to commercially valuable products. Waste disposal and pollution are inextricably linked. Unwanted residues that are usually perceived to be of negative value are described as waste. The production of citrus juice on an industrial level leads to a considerable quantity of solid and liquid residue (8–20 million tons year⁻¹), which is considered as waste. Citrus processing residues possess no economic value. They are rich in soluble sugars, cellulose, hemicellulose, pectin, and essential oils that could form the basis of several industrial processes. Possible applications of these waste residues include fertilizer, cattle feed, charcoal, adsorption of chemical compounds, bioethanol production, and extraction of essential oils and pectin.

The majority of waste disposal situations involve pollution of various kinds. Thus, the solid wastes and its disposal is one of the serious problems in developing countries, which require eco-friendly treatment options. The bioethanol made from citrus waste biomass can offer immediate and sustained greenhouse gas advantages and also solve the problem of its disposal. The study proposes alternatives for the minimization and recovery of solid and liquid residues generated in the production of citrus processing with a view of industrial plants for its reuse and value addition, thus saving environment from its hazards.