固定化SRB处理低浓度含铬废水

TREATMENT OF THE WASTEWATER CONTAINING LOW CONCENTRATION OF CHROMIUM BY IMMOBILIZED SRB

主要选用海藻酸钠和聚乙烯醇等为包埋剂,采用包埋法对SRB细菌进行固定化,并且以固定化小球对铬的去除率为主要参考指标,从失重率、传质性等方面综合考虑,通过正交试验确定固定化小球的最佳配比,同时采用这种新型的固定化小球处理含低浓度铬废水。试验结果表明,固定化SRB小球的最佳包埋条件为:聚乙烯醇8%,二氧化硅2%,海藻酸钠0.2%,活性炭3%,菌液含量30%,饱和硼酸中氯化钙2%,交联时间24 h。固定化小球处理低浓度含铬废水的最佳条件为:p H为6,温度为30℃,初始铬离子浓度为1 mg/L,在250 min内小球表面的活性位点趋于饱和,此时Cr去除率为92%。

Sodium alginate and polyvinyl alcohol（ PVA） were used as embedding agents to generate immobilized SRB cell in this study. The chromium ion removal rate were taken as the mainly reference index. Based on comprehensively considering weightlessness rate and the transmission medium properties,the optimal proportion of immobilized SRB were determined by orthogonal experiment. The new type of immobilized ball was used to treat wastewater containing low concentration of chromium. The results showed that the optimal embedding conditions of the immobilized SRB balls were as following： The mass fractions of PVA,silicon dioxide,sodium alginate,active carbon,microbial and calcium chloride were 8%,2%,0. 2%,3%,30%,2%,respectively,the crosslinking time was 24 h。The optimal conditions of immobilized pellets treating wastewater containing low concentration of chromium were p H of 6,temperature of 30 ℃ and the initial chromium ion concentration of1 mg / L,the length of time of 250 min. At the optimum conditions,the chromium ion removal rate was 92% 。