Optimize system configuration and operation condition of anaerobic baffled reactor (ABR) and anaerobic filter (AF) for treating domestic wastewater.

This study aims to optimize the system configuration and operation condition of the decentralized anaerobic baffled reactor (ABR) and anaerobic filter (AF) for treating domestic wastewater. Laboratory scale of ABR consisting of 66 liters working volume with eight compartments and AF consisting of 52 liters with five compartments operated under hydraulic retention time (HRT) of 24 – 48 hr. For ABR, the inlet and outlet between each compartment were varied between 3 and 9 cm height while foam and ceramic filters were used in the AF system as attached growth and filter media. Within all operation conditions, the pH value in all reactors was around the neutral condition, 6.8 – 7.2, sufficient for microbial survival and organic and nitrogen degradation activity. For the ABR, the optimum condition was obtained under 48 hr HRT and 3 cm height of inlet and outlet between each compartment. In this case, total suspended solids (TSS) and chemical oxygen demand (COD) removal efficiencies were up to 93% and 92%, respectively. It can note that obtained optimum condition provided about 4% – 23% higher than other conditions. Likewise, AF operating with foam medium was found as an optimum condition. COD and TSS removal in AF could reach 92% and 91%, respectively, while other conditions provided only 82% – 89%. However, both systems are commonly designed for anaerobic digestion only; fluctuation of nitrogen removal could reveal the presence of active microorganisms, which has responded to ammonia, nitrate, and nitrite removal. In summary, the HRT of 48 hr in ABR and AF could highly remove organic compounds from domestic wastewater. The 3 cm heigh of inlet and outlet from each compartment could enhance the contact time between wastewater and sludge. At the same time, the foam medium could act simultaneously as attached growth media and filter. Moreover, six compartments of ABR and two compartments of AF could treat domestic wastewater to reach the effluent standard of Cambodia. [ABSTRACT FROM AUTHOR]