一株粘质沙雷氏菌对污染水体中镉的去除条件研究

Removal Condition of Cadmium from Polluted Water by a Strain of Serratia Marcescens

水体中重金属污染问题亟待解决,而微生物在水体污染治理中具有显著优势。因此,本文将已从土壤中筛选出的一株对重金属具有耐性的粘质沙雷氏菌(AR1 KX343948.1)用于水体中镉(Cadmium,Cd)污染物的去除。采用控制变量法对粘质沙雷氏菌去除Cd的条件进行了研究,并采用电感耦合等离子法检测耐性菌作用后Cd的浓度变化。结果表明:在实验条件范围内,当Cd浓度为3 mg/L、加菌量为4%、pH为9.4、菌龄为4.5 h及处理时间为96 h时,粘质沙雷氏菌对Cd的去除效果最优,且最高去除率为91.00%。耐性菌对Cd的去除效果在偏低浓度(3~6mg/L)条件下更加显著,对3 mg/L的Cd的去除效率最高,且随加菌量的增加耐性菌对Cd的去除总体呈上升趋势。但在Cd的浓度为12.5 mg/L时,加菌量的增加会抑制耐性菌对Cd的去除。此外,随着处理时间的增加,耐性菌对Cd的去除率不断地增加。

It is urgent to solve the problem of heavy metal pollution in water,and microorganisms have a significant advantage in the treatment of water pollution.Therefore,in this paper,a strain of Serratia marcescens(AR1 KX343948.1)which is resistant to heavy metals was screened out from the soil for the removal of Cadmium(Cd)pollutants in water.The conditions for Cd removal by Serratia marcescens were studied by using control variable method,and the concentration of Cd was measured by inductively coupled plasma method.The results showed that:within the range of experimental conditions,when the concentration of Cd was 3 mg/L,the amount of added bacteria was 4%,the pH was 9.4,the age of bacteria was 4.5 h and the treatment time was 96 h,the removal effect of serratia marcescens on Cd was the best,and the highest removal rate was 91.00%.The removal effect of resistant bacteria on Cd was more significant at low concentration(3~6 mg/L),and the removal efficiency of 3 mg/L Cd was the highest,and the removal of Cd by resistant bacteria increased with the increase of the amount of added bacteria.However,when the concentration of Cd was 12.5 mg/L,the increase of the amount of bacteria would inhibit the removal of Cd by the resistant bacteria.In addition,Cd removal rate of resistant bacteria increased with the increase of treatment time.