PAM对制药污泥脱水性能改善及毒性削减

制药污泥的脱水处理及毒性削减是当前业界的研究热点。以污泥脱水性能(污泥比阻和泥饼含固率)和污泥综合急性毒性为评价指标,对2种不同型号PAM处理污泥的投加量进行优化,讨论了污泥絮凝脱水和毒性削减的机理。研究结果表明,处理100 mL原污泥,当制药污水厂现场使用的德国天使PAM和拓普戴克TOP8321型PAM投加量分别为4mg/L和12 mg/L时,污泥脱水性能达到最佳,此时污泥比阻从0.730×1012cm/g分别降低至0.126×1012cm/g和0.034×1012cm/g,泥饼含固率从16.32%分别提高至46.89%和34.98%;在毒性削减方面,2种混凝剂都可将污泥上清液毒性由微毒降至无毒,但对污泥毒性的削减效果不明显。对2种PAM的处理成本进行估算发现,污水厂现场使用的PAM对处理该制药污泥效果更佳,且费用相对较低,但要大幅度削减制药污泥的毒性需串联相应毒性削减技术和混凝沉淀单元。

Dewaterability improvement and toxicity reduction of pharmaceutical sludge using PAM

The dewatering and toxicity reduction of pharmaceutical sludge are the hotspots of current researches. Choosing the dewaterability and the comprehensive acute toxicity as the evaluation indicators, the dosages of two different types of PAM were optimized, and the mechanism of dewatering and toxicity reduction was discussed. The results indicated that the dewaterability of the sludge would reach the optimum when the dosages of the PAM used in the pharmaceutical sewage treatment plant and the TOP8321 PAM bought from Toprotect were 4 mg/L and 12 mg/L, respectively. The specific resistance reduced from 0.730×10¹² cm/g to 0.126×10¹²cm/g and 0.034×10¹²cm/g, and the solid content increased from 16.32% to 46.89% and 34.98%, respectively. In the aspect of toxicity reduction, both the PAMs could reduce the toxicity of liquid supernatant to nontoxic, but didn't work obviously on the toxicity reduction of the sludge. The result of the estimation on the treatment cost of the two PAMs indicated that the PAM used in the pharmaceutical sewage treatment plant was more effective and cheaper. However, the technique of toxicity reduction should be combined with coagulating sedimentation section to reduce the toxicity of the pharmaceutical sludge drastically.