Biological treatment of poultry slaughterhouses wastewater by using aerobic moving bed biofilm reactor

Abstract

Wastewater emerging from poultry technical slaughterhouses is characterized by its high degree of pollution in terms of organic content. This causes a rise in organic load disposed to wastewater treatment plants and thereby drooping efficiency. Effective and economical ways to treat such wastewater, based on reducing concentration of organic loads to appropriate level, preserves environs and reduces treatment costs for owners of industrial plants without augmenting investment costs. Aerobic Moving Bed Biofilm Reactor (MBBR) technology based on biofilm phenomenon is advocated in this research work. An active biofilm developing on plastic carriers (composed of polyethylene granular particles, PE) is placed in a reactor. The suspended carriers are kept in constant motion, their sizeable active surface fostering swift weight gain of microorganisms. This technology proved successful in removing pollution generated by poultry wastewater in treatment plants as measured by different indicators.This research work encouraged the use of aerobic moving bed biofilm reactor for treatment of poultry slaughterhouses wastewater. The increase in thickness of biological membrane formed around the plastic bed granules led to emergence of an oxygen deficient area around the bed particles that helped removing nitrates. Both TDS and COD values decreased, with increasing age of reactor. Continuous improvement in removal efficiencies of COD and TDS is noted with increasing reactor detention time. The increase in organic load has reduced removal efficiency of COD, TDS, NO₃^– and PO₄^3-.

Keywords: Poultry slaughterhouse, mobile bed biofilm reactor, attached biological membrane, organic load, biological treatment, detention time