Acta Chim. Sinica ›› 2017, Vol. 75 ›› Issue (6): 552-559.DOI: 10.6023/A17020058 Previous Articles     Next Articles

Special Issue: 铁环境化学




  1. 南京农业大学 资源与环境科学学院 南京 210095
  • 投稿日期:2017-02-15 发布日期:2017-04-12
  • 通讯作者: 周立祥
  • 基金资助:


Biomineralization: a Pivotal Process in Developing a Novel Passive Treatment System for Acid Mine Drainage

Zhou Lixiang   

  1. College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095
  • Received:2017-02-15 Published:2017-04-12
  • Contact: 10.6023/A17020058
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21637003, 41371476).

Biomineralization, a ubiquitous phenomenon found in nature, is a process of the formation of mineral crystal mediated biologically. However, little information is available on how to consciously regulate and strengthen this biomineralization process with an aim to treat effectively wastewater. Here we develop a novel passive biomineralization-limestone ditch treatment system (PBDTS) for purifying toxic metal-containing acid mine drainages (AMD) generated in many mines. It is well documented that the treatment of AMD by traditional passive limestone ditch treatment system (PLDTS) consume a large amount of lime and consequently produce many toxic residue to be treated due to high concentration of dissolved iron and sulphate in AMD. In the paper, Acidithiobacillus ferrooxidans biofilm formed in elastic filler packed in AMD will oxide Fe2+in AMD into Fe3+ and subsequently form biogenic schwertmannite[Fe8O8(OH)6SO4]. Newly formed schwertmannite as a crystal seed will grow by self and scavenge, to a great extent, most of toxic metalloid As and a few of heavy metal cation through co-precipitation and/or adsorption processes. The remaining non-mineralized Fe3+ is reduced to Fe2+ by Acidiphilic iron-reducing bacterial (Acidiphilium sp.) immobilized in slow-release organic carbon-source material filled in next stage of AMD ditch. The resulting Fe2+ from the biological reduction of Fe3+ are re-oxidized by Acidithiobacillus ferrooxidans and hydrolyzed to form schwertmannite through several oxidizing-reducing cycles. As a result, most of soluble Fe and sulphate in AMD can be removed and recovered in the form of schwertmannite in acidic AMD environment. The effluent of AMD pretreated by biomineralization could be neutralized and easily reach a water quality standard by China only with a few of lime. The results from simulation test showed that such a novel PBDTS could save more than 80% of lime requirement amount and produce less than 10% of toxic neutralized residues with comparison to traditional PLDTS. Moreover, the levels of nonferrous metals in the neutralized residues obtained in PBDTS are more than 10 times higher than that in PLDTS. Therefore, the neutralized residues obtained in PBDTS could be considered as nonferrous metal mine to be exploited. Undoubtedly, more attention should be paid to the role of biomineralization in wastewater treatment. Finally, future research needs are proposed in the paper.

Key words: acid mine drainage, biomineralization, heavy metal, Acidithiobacillus ferrooxidans, schwertmannite