Guo Jing, Kang Yong, Feng Ying
School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China.
School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China.
J Environ Manage. 2017 Dec 1;203(Pt 1):278-285. doi: 10.1016/j.jenvman.2017.07.075. Epub 2017 Aug 10.
A simple and valid toxicity evaluation of Zn, Mn and Cr on sulfate-reducing bacteria (SRB) and heavy metal removal were investigated using the SRB system and SRB+Fe system. The heavy metal toxicity coefficient (β) and the heavy metal concentration resulting in 50% inhibition of sulfate reduction (I) from a modeling process were proposed to evaluate the heavy metal toxicity and nonlinear regression was applied to search for evaluation indices β and I. The heavy metal toxicity order was Cr > Mn > Zn. Compared with the SRB system, the SRB+Fe system exhibited a better capability for sulfate reduction and heavy metal removal. The heavy metal removal was above 99% in the SRB+Fe system, except for Mn. The energy-dispersive spectroscopy (EDS) analysis showed that the precipitates were removed primarily as sulfide for Zn and hydroxide for Mn and Cr.The method of evaluating the heavy metal toxicity on SRB was of great significance to understand the fundamentals of the heavy metal toxicity and inhibition effects on the microorganism and regulate the process of microbial sulfate reduction.
利用硫酸盐还原菌（SRB）系统和SRB+Fe系统，对锌、锰和铬对硫酸盐还原菌的简单有效毒性评估以及重金属去除情况进行了研究。提出了通过建模过程得出的重金属毒性系数（β）和导致硫酸盐还原抑制50%的重金属浓度（I）来评估重金属毒性，并应用非线性回归来寻找评估指标β和I。重金属毒性顺序为Cr＞Mn＞Zn。与SRB系统相比，SRB+Fe系统表现出更好的硫酸盐还原和重金属去除能力。除锰外，SRB+Fe系统中重金属去除率高于99%。能量色散光谱（EDS）分析表明，沉淀物主要以硫化物形式去除锌，以氢氧化物形式去除锰和铬。评估SRB上重金属毒性的方法对于理解重金属毒性的基本原理以及对微生物的抑制作用和调节微生物硫酸盐还原过程具有重要意义。
