title: Effect of neutralized solid waste generated in lime neutralization on the ferrous ion bio-oxidation process during acid mine drainage treatment.
abstract: Bio-oxidation of ferrous ions prior to lime neutralization exhibits great potential for acid mine drainage (AMD) treatment, while slow ferrous ion bio-oxidation or total iron precipitation is a bottleneck in this process. In this study, neutralized solid waste (NSW) harvested in an AMD lime neutralization procedure was added as a crystal seed in AMD for iron oxyhydroxysulfate bio-synthesis. The effect of this waste on ferrous ion oxidation efficiency, total iron precipitation efficiency, and iron oxyhydroxysulfate minerals yield during ferrous ion bio-oxidation by Acidithiobacillus ferrooxidans was investigated. Ferrous ion oxidation efficiency was greatly improved by adding NSW. After 72 h incubation, total iron precipitation efficiency in treatment with 24 g/L of NSW was 1.74-1.03 times higher than in treatment with 0-12 g/L of NSW. Compared with the conventional treatment system without added NSW, the iron oxyhydroxysulfate minerals yield was increased by approximately 21.2-80.9% when 3-24 g/L of NSW were added. Aside from NSW, jarosite and schwertmannite were the main precipitates during ferrous ion bio-oxidation with NSW addition. NSW can thus serve as the crystal seed for iron oxyhydroxysulfate mineral bio-synthesis in AMD, and improve ferrous ion oxidation and total iron precipitation efficiency significantly.
authors.affiliation: Environmental Engineering Laboratory, College of Resource and Environment, Shanxi Agricultural University, Taigu 030801, China.
authors.forename: Fenwu
authors.initials: F
authors.lastname: Liu
authors.affiliation: College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China. Electronic address: lxzhou@njau.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Lixiang
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Environmental Engineering Laboratory, College of Resource and Environment, Shanxi Agricultural University, Taigu 030801, China.
authors.forename: Shasha
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Environmental Engineering Laboratory, College of Resource and Environment, Shanxi Agricultural University, Taigu 030801, China.
authors.forename: Lanlan
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Environmental Engineering, College of Resources and Environmental Science, Hubei University, Wuhan 430062, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
mesh_terms: D042763:Acidithiobacillus / Q000378:metabolism; D017610:Calcium Compounds / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D008906:Mining; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D062611:Solid Waste; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D017610:Calcium Compounds; D005296:Ferrous Compounds; D010087:Oxides; D062611:Solid Waste; D014874:Water Pollutants, Chemical; C016538:lime
keywords: Ferrous ion oxidation efficiency; Iron oxyhydroxysulfate mineral; Neutralized solid waste; Total iron precipitation efficiency