生物成矿与铁还原耦合在酸性重金属废水处理中的作用与机制

项目名称： 生物成矿与铁还原耦合在酸性重金属废水处理中的作用与机制

项目编号： No.21477054

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 化学工业

项目作者： 梁剑茹

作者单位： 南京农业大学

项目金额： 90万元

中文摘要： 由于许多重金属酸性废水中Fe3+和硫酸根严重影响石灰中和效果，因此，本项目的目的是研究新的方法和构建新原理旨在酸性条件下去除Fe3+和硫酸根，为后续石灰中和扫除障碍。受AMD等自然环境中A.f菌能促进羟基硫酸铁矿物形成的启发，并结合以前的研究中发现的在常温常压和非生物环境下Fe3+在含硫酸根的酸性环境下不能直接水解形成羟基硫酸铁矿物，但却能在嗜酸性氧化亚铁硫杆菌(A.f)促进下通过氧化Fe2+而容易形成羟基硫酸铁矿物的机理，深入研究A.f菌促进Fe3+和硫酸根生物成矿的调控原理，重点探索Fe3+还原和生物成矿耦合循环大幅提高废水中铁和硫酸根生物成矿率的效果和机制，及其对后续石灰中和效果的影响。在上述研究基础上，初步构建用于处理酸性重金属废水的Fe3+还原耦合下的高效生物成矿-石灰中和系统模型，为众多酸性重金属废水处理提供新原理新方法。

中文关键词： 重金属；废水；生物成矿；嗜酸性氧化亚铁硫杆菌；铁

英文摘要： Fe3+ and SO42- in acidic heavy metal-containing wastewater was found to drastically reduce lime neutralization efficiency of the wastewater. Thus,the purpose of this proposed project is to explore or establish a novel method for scavenaging Fe3+ and SO42- in this acidic wastewater and to enhance lime neutralization efficiency. In light of the spontaneous formation of biogenic iron hydroxylsulfate minerals facilitated by Acidithiobacillus ferrooxidans (A.f.)in Acid Mine Drainage (AMD),considering the already-obtained mechanism of iron hydroxylsulfate mineral not to be spontaneously formed by Fe3+ hydrolysis under acidic and abiotic ambient condition but its formation occurred when Fe3+ derive from the bio-oxidation of Fe2+ by A.f., we further study the regulating principle of biological mineralization of Fe3+ and SO42- by A.f. Futhermore, the chemical reduction of Fe3+ coupled with the resulting Fe2+ bioxidation and subsequent mineralization are used to improve greatly the removal effficiency of Fe3+ and SO42- in the wastewater through biogenic mineral formation. The lime neutralization efficiency of the pretreated acidic wastewater will be investigated in details. On basis of the output mentioned above, a novel model with biological minerlization coupled with Fe3+ reduction and subsequent lime neutralization will be established. The outcome of the proposed project is helpful in obtaining a new principle or method to treat acidic heavy metal-containing wastewater.

英文关键词： Heavy metal;Wastewater;biological mineralization;Iron-oxiding bacterial;Iron