Nitrogen Transformation in Two-Phase Anaerobic System of Monosodium Glutamate Wastewater Treatment

摘要

The present work was to investigate the nitrogen-existing forms of monosodium glutamate wastewater and the effects of HRT, organic loading and biomass on the transformation of nitrogen in the full-scale operation of two-phase anaerobic process. The ratio of ammoniacal nitrogen (NH_4~+-N) to total nitrogen (TN) varied from 0.5 in acidogenic phase reactor (Phase I) to 0.85 in methanogenic phase(Phase II), which indicated that ammonium had already become the leading form in Phase II. The ammonia-releasing amount varied greatly at different hydraulic retention time (HRT), especially with the lower HRT of 15h in Phase I and 50h in Phase II, which the ammonia-releasing increased as the decreased HRT on the day 70 to 90. Calculated the removal rate of COD and TN in the different heights of the methanogenic reactor, the values of COD_(rem)/TN_(rem) obtained from the height of 3.0-5.0m and 5.0-10.0m were 22.2:1 and 12.0:1 respectively. The reduction of TN concentration in the height of 5.0-10.0m was 244.5mg/l that was almost 45 percents of the total reduction in Phase II, but the mean sludge concentration of 2698.7mg/l in the height of 5.0-10.0m was lower than the mean sludge concentration of 8943.3mg/l in the height of 3.0-5.0m. The nitrogen imbalance was occurred in the post section of the methanogenic reactor.