The study on Anaerobic Digestion of Wastewater Containing Organic Solids

An anaerobic wastewater treatment process has been applied mainly to the wastewater of high TOD (Total Oxygen Demand) strength but with less suspended solids. This study examined the property of treatabililty of the artificial wasterwater compounded with wheat starch (TOD 20000mg/l, SS 15000mg/l) under mono-phase fixed-bed anaerobic digestion. The test result showed dependency of TOD removal and gas generation on TOD volumetric loading. Namely, TOD removal maintained 90 to 95% as long as TOD load was within 7kg/m3·d. Most solids were digested to methane gas at the rate of 0.33Nm3/kg TOD removed, decreasing the SS concentration in outfall from the reactor to less than 1000mg/l. Thus the study proved the possibility of diversified application of anaerobic process to the wastewater with high organic suspended solids from economical viewpoint.