Management options for coffee processing wastewater. A review

Coffee processing wastewater is one of the major agro-processing wastes that put high pollution pressure in coffee growing and exporting countries affecting water, soil, and human health. The processing industries apply no or low efficient technologies for management due to a lack of economic and technological feasibility. The purpose of this review was to assess ever practiced and studied management options of coffee processing wastewater and design feasible alternatives suitable for coffee-producing and agrarian regions. Treatment/management efficiencies of the advanced oxidation process, coagulation-flocculation, adsorption, wetland system, anaerobic digestion and fertigation along with their limitations were considered in this review. Most importantly, this work demonstrates fertigation as the first choice of coffee effluent management for agrarian coffee-producing countries due to low cost, additional nutrient value and ease of technological application.