选矿废水中黄药的生化处理

针对选矿废水中低浓度黄药和金属离子共存的工程实际,采用摇床振荡培养法,利用对黄药有降解性能的菌群,研究了共代谢基质、氮源、碳氮比及金属离子(Fe3+、Zn2+和Pb2+)对菌群降解黄药的影响。研究表明,由于共代谢基质化学结构不同,其对降解的促进作用依次是:多糖 > 二糖 > 单糖;氮源中氯化铵和尿素的促进作用较其他氮源(酵母膏、硝酸钠、亚硝酸钠)好;高碳氮比有利于黄药的降解。0~20 mg/L的Fe3+可促进微生物对黄药的降解;10 mg/L的Zn2+对黄药降解有促进作用,20 mg/L时影响不显著,在浓度为30~50 mg/L的范围内表现出抑制作用;4 mg/L的Pb2+已经对黄药的生物降解表现出抑制作用,且随着Pb2+浓度的升高,抑制作用增强。

Biological treatment of xanthate in floatation wastewater

The effects of co-metabolism substrates,nitrogen sources,C/N ration and metal ions(Fe3+,Zn2+ and Pb2+) on microbial degradation of xanthate were investigated considering the actual conditions that low concentration of xanthate and coexisting metal ions exist in floatation wastewater.Polysaccharide,disaccharide and monosaccharide were selected as co-metabolism substrates.Ammonium chloride,urea,yeast extract,sodium nitrate and sodium nitrite were used as nitrogen sources.The results demonstrated that co-metabolism substrates enhance the biodegradation of xanthate.However,the enhancement vary due to the difference in chemical structure and is in the order:polysaccharides > disaccharides > monosaccharide.Ammonium chloride and urea is better because of high nitrogen content in them,following by yeast extract.The nitrogen in sodium nitrate and sodium nitrite is difficult to be used by this mixed species.Higher C/N ration is in favor of biodegradation of xanthate.With the increase in Fe3+ concentration from 0 to 20 mg/L,the microbial degradation of xanthate is enhanced.10 mg/L of Zn2+ slightly increased biodegradation while in 20mg/L the effect is not significant,and the biodegradation is inhibited in the range of 30-50 mg/L.Pb2+ is inhibitory to microorganisms,4 mg/L of Pb2+ inhibit the biodegradation of xanthate,the inhibition become more evident with the increasing concentration of Pb2+.