印染废水处理中厌氧处理时间对后续混凝的影响

Effect of the Anaerobic Retention Time on Subsequent Coagulation in Dyeing Wastewater Treatment

以含活性染料为主的印染废水为研究对象,将经过厌氧处理后的印染废水与原印染废水分别进行混凝脱色实验,初步探讨了厌氧停留时间对废水后续混凝的影响。实验研究表明,厌氧后出水混凝COD去除率较原水直接混凝去除率有所降低。废水的厌氧停留时间越长,厌氧后出水混凝脱色所需的药剂越少,混凝产生的物化污泥也越少。当停留时间达到18小时以上时,后续混凝较原水直接混凝所需药剂和产污泥量分别减少39%-45%,27%-34%。

With the active dyes in dyeing wastewater as study object, the coagulation experiments of anaerobicly treated dyeing wastewater and original dyeing wastewater without anaerobic treatment were carried out, and the effect of the anaerobic retention time on subsequent coagulation was studied. The results showed that the COD removal of coagulation for anaerobicly treated effluent had little decline comparing with direct coagulation for dyeing wastewater without anaerobic treatment. The longer the anaerobic retention time, the less the coagulant dosage needed, and the less the sludge produced. When the anaerobic retention was up to 18 hours or above, the coagulant dosage and produced sludge quantity reduced by 39% - 45% and 27% - 34% respectively comparing with the direct coagulation without anaerobic treatment.