抄録
We investigated the suppressive effects on filamentous bulking by the addition of calcium polysulfide (CPS) . Laboratory experiments were conducted on three activated sludge systems with various loadings of CPS. The influent CPS in the three systems were 0, 100, and 200mg⋅l-1. All systems were operated under the same conditions, that is 0.24kg⋅m-3⋅day-1 of TOC volumetric loading rate, 24 hours of hydraulic retention time, temperature at 25°C, and were approximately operated at the same sludge loadings. A mixture of glucose and pepton was used as the substrate and easily caused the filamentous bulking. The mixed cultures developed in the systems mentioned possessed average SVI values of 400, 232, and 129ml⋅g-1 respectively. From microscopic and microbial observation, the high SVI value was caused by a high content of filamentous microorganisms in the developed mixed cultures. The series with CPS had different microflora compared with the control series with no loading of CPS. It was concluded that CPS suppressed the growth of filamentous microorganisms, and led to the growth of non-filamentous ones, i.e., Zooglea-like flocs.
