鼠李糖脂对剩余污泥中铜和镍的去除

采用批次淋洗的方法研究了鼠李糖脂浓度、pH、淋洗时间、提取次数以及重金属形态对剩余污泥中Cu和Ni去除效果的影响。结果表明,随着鼠李糖脂浓度的增加,2种重金属的去除率增加,且鼠李糖脂在碱性条件下对Cu和Ni的去除效果较好,最高去除率可分别高达80.77%和46.74%;随着振荡时间和提取次数的增加,Cu和Ni的去除率随之增加,并明显高于去离子水的提取;对污泥重金属形态进行分析发现,鼠李糖脂能有效去除酸提取态的Cu和Ni。研究结论可为剩余污泥的资源化而产生重金属安全隐患问题提供解决的参考方案和奠定理论基础。

Removal of cooper and nickel from excess sludge by rhamnolipid

The washing process in a batch experiment was conducted to investigate the performance of rhamnolipid on removal of cooper (Cu) and nickel (Ni) from excess sludge. Various factors such as concentration, pH, contact time, washing times and distributions of heavy metals were studied. The results showed that the removal efficiency of Cu and Ni increased with the increase of rhamnolipid concentration. Rhamnolipid showed a better removal efficiency of Cu and Ni in alkaline condition, getting the highest removal efficiency of 80.77% and 46.74%, respectively. In addition, with the increase of contact time and washing times, higher removal efficiency was obtained and rhamnolipid performed significantly better than deionized water. The fractionations of heavy metals were identified using the sequential extraction. It indicated that rhamnolipid was effective in removing the exchangeable and carbonated fractions of Cu and Ni from sludge. As a whole, this study will provide a reference solution and theoretical foundation to the problems of security risks of heavy metals in recycling excess sludge.