蠕虫污泥减量效果及其影响因素分析

研究了蠕虫生长在活性污泥法中试系统的污泥减量效果及其对出水水质的影响 ,同时对蠕虫生长的影响因素进行了初步分析 .结果表明 ,除了初始的20d之外 ,整个试验过程中均有蠕虫出现 ,其中红斑瓢体虫(Aeolosomahemprichicii)和仙女虫(Naiselinguis)交替占据优势地位 ,但红斑瓢体虫占据主导地位的时间长于仙女虫 ,而吻盲虫 (Pristinaaequiseta)只是偶尔存在 .蠕虫连续保持高密度生长 (曝气池中蠕虫总密度大于 30条 /mg)长达 172d .高密度下的蠕虫生长不仅能显著降低污泥产率 ,而且能明显提高污泥的沉降性能 .蠕虫密度越高 ,出水水质越差 .仙女虫比红斑瓢体虫具有更大的污泥减量能力 ,并且前者对出水水质的影响也大于后者 .蠕虫生长不影响硝化过程 ,但当仙女虫占优势时 ,蠕虫生长会导致出水PO3₄^3--P浓度的升高 .蠕虫生长影响因素的分析表明 ,只有污泥龄对 2种蠕虫的生长没有影响 ,但温度和水力停留时间均能显著影响它们的生长 .

Reducing Sludge Production by Predation and Its Factors Analysis in Conventional Activated Sludge Process

Reducing excess sludge production induced by Oligochaete is carried out in a pilot scale of conventional activated sludge (CAS) reactor for 345 days. Worms occurred for nearly whole operating period except for the first 20 days, and continuously maintained at high density (over 30 total worms/mgVSS in aeration tank) for 172 days. Three types of worm were found, Aeolosoma hemprichicii and Nais elinguis alternatively dominated, but Pristina aequiseta occasionally presented. High worm density greatly contributes to both reducing sludge production and improving the sludge settling characteristics, and Nais elinguis had more potential for sludge reduction than Aeolosoma. Worm growth had impacts on effluent quality, and Nais elinguis growth affected effluent quality much more than Aeolosoma. Worm growth does not disturb the nitrification process, but PO₄^3--P release into effluent occurres as Nais elinguis dominated. Analysis of factors affecting worm growth show that only SRT has no any impact on neither Aeolosoma nor Nais, however, both temperature and HRT can affect their growth very much.