Experimental studies on the application of the MiFs system adopting an autothermal aerobic digestion for pre-treatment of livestock wastewater

Abstract

The research was conducted to investigate the effects of temperature and contaminants removal efficiency as digestion period on the Autothermal Thermophilic Aerobic Digestion (ATAD) process. The ATAD process for biological treatment of livestock wastewater is a method of the utilization of released heat by oxidation of organic matter, using the anabolic and catabolic activity of aerobic organisms, without exogenous heat. The major advantages of ATAD process have rapid biodegradation rates, low sludge yields, low emission of offensive odor, the ability to inactivate pathogenic microorganisms, and excellent process stability. The MiFs (MultiFunction Storage) system adopting the ATAD process, developed by Seoul National University, was operated to test the applicability to biologically treat livestock wastewater. In full-scale operation, without external heat supply, the temperature increased up to 63¡É, 57¡É, 47¡É in each test. The biodegradation of organic matter by oxidation increased rapidly with time and the removal efficiency of contaminants were initially high, but reduced progressively as the autothermal aerobic digestion extended. Obtained maximum removal efficiency of TSS (Total Suspend solids), VSS (volatile Suspend solids), BOD5, and CODcr were 83%, 93%, 99% and 94%, respectively. E.coli and Salmonella spp. were completely destructed in the MiFs. Further work on the MiFs system with an ATAD process is also needed to determine optimum operating conditions such as hydraulic retention times (HRT), oxygen uptake rates, aeration method.