化学解耦联剂对活性污泥工艺中污泥产率的影响

采用3,3′,4′,5-四氯水杨酰苯胺(TCS)作为代谢解耦联剂添加到活性污泥工艺中,连续曝气分批培养实验结果表明,TCS在浓度高于1.0mg/L时是一种有效的化学解耦联剂,能显著地降低污泥产率.当TCS浓度为6.0mg/L时,污泥产率可降低约50%.在40d的运行期间,隔天分别在3个反应器中添加TCS 2.0、2.8和3.6mg/L,基质的去除能力和出水氨氮及总氮浓度均未受影响,污泥的SOUR值和脱氢酶活性相应增加,污泥的沉降性能也未见有明显影响.镜检发现,对照反应器中的污泥经40d运行后仍有丝状菌存在,而添加解耦联剂反应器中的污泥几乎无丝状菌的存在.以上结果表明,可以应用TCS来降低活性污泥工艺中的剩余污泥产量.

The Use of Chemical Uncoupler to Reduce Sludge Yield in Activated Sludge Process

To determine whether chemical additions can be used to reduce sludge production in biological wastewater treatment, 3,3',4',5-tetrachlorosalicylanilide (TCS), served as a metabolic uncoupler was added to activated sludge cultures. The batch tests have confirmed that TCS is an effective chemical uncoupler in reducing the sludge yield when its concentration is higher than 1.0 mg/L. It was showed that TCS was able to reduce sludge yield by approximately 50% when the TCS concentration was 6.0 mg/L. It was also revealed that substrate removal capability and effluent nitrogen concentration were not affected adversely by the presence of TCS when TCS was dosed every other day in a range of 2.0-3.6 mg/L during the 40 d operation of activated sludge batch cultures. Such a sludge growth reduction is associated with the enhancement of microbial activities in terms of the SOUR and dehydrogenase activity. Sludge settleability from the treated and control samplers was comparable and not significantly different. Meanwhile, there was a finding that the filamentous bacteria still grow in sludge floc in the control reactor after 40 d operation. These results suggested that it might be possible to apply TCS in activated sludge systems to reduce the excess sludge yield.