Growth Characteristics of Aeolosoma Hemprichi Contributing on Excess Activated Sludge Reduction

In order to stabilize the growth of A.hemprichi and minimize the sludge production through biological predation, A.hemprichi was inoculated in batch and continuous experiments to investigate the growth characteristics and the effect on sludge reduction in this study. Various available volatile suspended solid(AVSS) concentrations were obtained after the ultrasonic irridation on pre-sterilized sludge. It was found the density of A.hemprichi was proportionate to AVSS concentration. A.hemprichi reached the maximum density when AVSS concentration was more than 3000 mg/L. No obvious difference was found between the initial specific growth ratio(mu) of A.hemprichi at various AVSS concentrations. When N > 0.5N_L, mu decreased with the increase of A.hemprichi and Logistic model was adopted to fit the growth of A.hemprichi. The results indicated sludge reduction rate was correlated with the growth rate of A.hemprichi which got the maximum growth activities at the density of 300 ind./ml. SRT of 6 ~ 8 days could control A.hemprichi at this optimum density.