Performance of the UASB Pilot Scale Reactor in Treating MSW Leachate in the Hot Climate City of Ahvaz

This study was conducted to determine the efficiency of the up-flow anaerobic sludge blanket (UASB) process in treating the leachate from the municipal solid waste (MSW) in the city of Ahvaz, Iran, under tropical conditions. A pilot scale UASB reactor with a total volume of 30 L was seeded with anaerobic sludge from the sugarcane plant to which diluted municipal leachate was introduced as influent feed. The organic loading rate (OLR) of the reactor was increased from 0.58 to 15 g COD/L.d over a period of 230 days. A maximum COD removal efficiency of 87% was obtained for an organic loading rate of 12 g COD/L.d. The temperature of the reactor was maintained in the range 34-39 ºC during the study period. The maximum reactor temperature (39 ºC) highest reactor temperature (37-39 ºC). The results reveal that the UASB reactor is a feasible one for treating reached was due to the effect of ambient temperature. The highest COD removal efficiency was obtained at the MSW leachates as witnessed by its successful operation in the hot climate of Ahvaz (with an average temperature of 40 ºC over about 7-8 months of the year) and by its potential for receiving and treating high organic loading rates with a high COD removal efficiency (87%). However, an aerobic system must be used after the UASB reactor for the effluent to meet the standards defined for the proposed disposal method.