菌藻共生生物膜对重金属镉的去除

Removal of Cd^(2+) by alga-bacteria biofilm

为了解淡水中存在的藻类及其伴生细菌所形成的菌藻共生系统对污水中微量重金属镉的去除作用,通过对菌藻生物膜上多聚糖、ATP的测定,研究淡水菌藻生物膜与镉的去除关系及温度、pH、离子浓度对去除效率的影响.结果表明,淡水中藻类及其伴生细菌对污水中镉离子有较强的去除能力,其适宜温度在25~40℃之间,最适温度为30℃,pH值在6~9之间处理效果较好,最佳pH为6.当镉离子初始浓度小于20mg/L时,生物膜分泌的多聚糖与水中镉离子去除率呈正相关,相关系数R2在0.909 3~0.945 9之间.利用菌藻共生生物膜处理低浓度重金属镉,重金属去除率高.

The algae and associated germs exist prevalently in natural aquatic environments , which can be used to remove heavy metal cadmium in waste water .Based on the polysaccharide of the biofilm and ATP testing ,the effect is studied of alga‐bacteria biofilm on removing the heavy metal cadmium from the sewage and the effect of temperature ,pH ,the initial concentra‐tion of cadmium on removal rate is also discussed .T he result show s that the alga‐bacteria in fresh water have a strong remotion capacity of cadmium in the sewage .The appropriate temper‐ature is 25~40℃ ,the pH 6~9 and the optimum temperature 30℃ ,and pH 6 .When the ini‐tial concentration of cadmium ion is less than 20mg/L ,the amount of polysaccharides w hich are secreted by the biological membrane and cadmium ions in water removal rate is positively relat‐ed ,and the coefficient of association R2 is between 0.909 3~0.945 9 .When the alga‐bacteria biofilm is used to remove the low concentration cadmium from waste water ,the removal rate is high .