Immobilized Anaerobic Microbial Cell for Treatment of Domestic Wastewater

Entrapped mixed microbial cell (EMMC) process demonstrated the good mechanical strength and durability. It was found to have small land requirement, stable operating characteristics and no need for sludge recycle. In addition, it can dramatically increase the SRT in the reactor that may help the anaerobic system to have better performance on the treatment of domestic wastewater.
The research was discussed the performance of using Immobilized anaerobic system to treat synthetic and real wastewater. The operation parameters of synthetic wastewater trial were influent COD concentration (700, 400, 200 mg/L) and HRT (12, 6, 4 hours). Then, Test the real domestic wastewater and discuss the results.
In the synthetic wastewater trial, the influent COD 400, 700 mg/L had better COD removal efficiency (about 90%) and the methane gas concentration (above 60%). However, at influent COD concentration below 200 mg/L may decrease the COD removal efficiency and methane concentration. The COD removal efficiency was 80% and methane concentration was 40%. Form the results, low concentration of influent COD as 200 mg/L may show the worse COD removal efficiency and methane conversion of anaerobic system.
In the real domestic wastewater trial, HRT was operated at 6 hours. The COD removal efficiency was 80% (average) and methane gas concentration 23.2% (average) with low gas production rate 0.038 m3/m3/d. Domestic wastewater may cause some inhibition to the anaerobic treatment system.
In conclusion, immobilized anaerobic microbial cell process has the potential to treat the organic matters in the domestic wastewater. However, it still needs further researches to clarify what cause the inhibition and how to enhance the utility of organic matters to convert into the methane gas.