Biological treatment of wastewater with high concentrations of zinc and sulfate ions from zinc pyrithione synthesis

生物法处理吡啶硫酮锌生产废水中高浓度锌离子和硫酸根离子（英文）

An enriched and domesticated bacteria consortium of sulfate-reducing bacteria(SRB)was used to treat wastewater from zinc pyrithione(ZPT)production,and the effects of different reaction parameters on sulfate reduction and zinc precipitation were evaluated.The single-factor experimental results showed that the removal rates of Zn2+and24SO?decreased with an increased ZPT concentration ranging from3.0to5.0mg/L.Zn2+and24SO?in wastewater were effectively removed under the conditions of30?35°C,pH7?8and an inoculum concentration of10%?25%.The presence of Fe0in the SRB system enhanced Zn2+and24SO?removal and may increase the resistance of SRB to the toxicity of Zn2+and ZPT in wastewater.A Box?Behnken design was used to evaluate the influence of the main operating parameters on the removal rate of24SO?.The optimum parameter values were found to be pH7.45,33.61°C and ZPT concentration of0.62mg/L,and the removal rate of24SO?reached a maximum of91.62%under these optimum conditions.

采用富集和驯化后的硫酸盐还原菌处理吡啶硫酮锌生产废水,并考察不同实验参数对硫酸盐降解和锌沉淀的影响。单因素实验结果表明:当吡啶硫酮锌浓度为3.0~5.0 mg/L时,锌离子和硫酸根离子的去除率呈明显下降趋势。当温度为30~35℃、pH为7~8、接种量为10%~25%时,锌离子和硫酸根离子都能得到有效去除。零价铁不仅能提高硫酸盐还原菌对硫酸根离子和锌离子的去除效果,还能加强硫酸盐还原菌对锌离子和吡啶硫酮锌毒性的抗性。此外,采用Box-Behnken法研究主要实验参数对硫酸盐去除率的影响。得到最佳实验条件如下:pH7.45、温度33.61℃、吡啶硫酮锌浓度0.62 mg/L。在最佳实验条件下硫酸根离子的去除率能达到最大值91.62%。