MT基因工程菌去除污水中Cd、Ni

MT genetic engineering bacteria for treatment of Cd,Ni in waste water

引言 微生物法处理含重金属的污水或污泥具有很多优点,其机理包括微生物对重金属离子的吸附、生物沉淀、转化、富集、螯合作用[1-2],同时可通过改变重金属的价态使其毒性降低。

Performance of a new URB（upflow-refluence-biomembrane）reactive column using MT（metallothionein）genetic engineering bacteria for treatment of heavy metal element as Cd,Ni in waste water was studied.The effect of filler such as active carbon,haydite,core carbon and aquamats ecobase on removal of Cd and Ni is also discussed.For all supported MT-genetic engineering bacteria fillers packed in column,the removal rate is all higher than 43%.For aquamats ecobase packing,the removal rate of Cd and Ni can reach up to 99.4% and 85.2% respectively,indicating that aquamats ecobase should be the most engineering filler studied.Under the conditions： flow rate 2 L·h-1,pH 9 in influent,reaction temperature 35℃,using URB reactive column and aquamats ecobase as filler,effect of heavy metal load-rate on the removal of Cd and Ni was investigated.The results showed that the optimum heavy metal load-rate for the URB reactor is 0.481 mg·mg-1.At the conditions： quiescence immersing aquamats ecobase filler in the 10% MT-genetic engineering bacteria liquid for 24 h,influent concentration of Cd2＋,Ni2＋ 100 mg·L-1,effect of reactive column temperature on the removal of Cd and Ni was also studied.The results showed that the optimum temperature is 35℃.The results demonstrate that MT-genetic engineering bacteria is of good compatibility and tolerability to Cd and Ni.The combination process of URB-reactor with MT-genetic engineering bacteria could be used for effective removal of heavy metal contaminant in waste water.