Performance Evaluation of Sequencing Batch Reactor for Treatment of Coffee Pulping Wastewater

Abstract

The coffee industry uses large amount of water during various stages of coffee production. Coffee processed by wet method generates large volume of high strength wastewater rich in COD and nutrients hence to comply with stringent environmental regulations and for restoration of safe environment, it has become imperative to find less costly and easily adaptable treatment technology. Coffee pulping wastewater characterized as acidic (3.92 – 4.99), high content of suspended and dissolved organic matter makes it amenable to rapid biodegradation. In the present study, Sequencing Batch Reactor (SBR) has been employed has an efficient technology for treating coffee pulping wastewater treatment because of its simple configuration and high efficiency in COD and nutrients removal. The COD in the influent coffee wastewater sample is 8320 to     10400 mg/l, influent phosphorus is 60 to 94 mg/l and influent nitrate nitrogen concentration is 32 to 52 mg/l. The COD concentration remaining in the effluent is 296 mg/l, phosphorus concentration is 3 mg/l and nitrate nitrogen concentration is less than 8 mg/l. With raw wastewater the SBR performance was low and after dilution (1:4) of coffee pulping wastewater the performance of SBR increased in terms of COD, nitrogen and phosphorus removal. This study also showed that there is a need for pre-treatment of coffee pulping wastewater since it contains recalcitrant with high COD concentration and low BOD concentration.