污泥浓缩池上清液的有机物分子量分布

Distribution of Molecular Weights of Organic Matters in Supernatant from Sludge Tihckener

研究了城市污水处理厂污泥浓缩池上清液有机物中分子量分布与浓缩时间、浓缩温度的关系。通过试验得知，对于高负荷活性污泥系统，当浓缩温度（２０℃）一定时，大、中、小分子均随着浓缩时间（０～４８ｈ）延长而增加，小分子增加量和比例最大；同样，当浓缩时间（４８ｈ）一定时，大、中、小分子均随浓缩温度升高而增加，小分子增加量和比例最大。对于低负荷活性污泥系统，经４８ｈ的浓缩，中分子占的比例最大。在特定的生化处理条件下（Ｔ＝２０℃，ｐＨ＝７），上清液有机物的总去除率为７１％，大分子基本没变，中分子略有降解，而小分子在０～２ｈ降解剧烈，２～５ｈ降解减缓，５～３０ｈ基本不变。

In the sludge thickening thank of a municipal wastewater treatment plant, the relationship between molecular weight distribution of organic matters in supernatant and the thickening time/temperature of the sludge was described in this paper. For the high-rate activated sludge process, when the thickening temperature was constant at 20℃, the quantity of organic matters corresponding to different molecular weight increased with the increase of the thickening time from 0 to 48h, in which the dissolved organic carbon (DOC) corresponding to small molecular increased from 8.5 to 574 mg/L and the ratio of small molecular also increased from 21% to 75%. When the thickening time was constant t 48 h, the quantity of all organic molecules increased with the increase of the thickening temperature from 10 to 30℃, in which the DOC corresponding to small molecular increased from 38 to 1 030 mg/L and the ratio of small molecular also increased from 17% to 67%. For low-rate activated sludge process, the largest portion(63%) of organic matters was corresponding to medium molecules after thickening time of 48 h.