Blais J F, Auclair J C, Tyagi R D
Institut national de la recherche scientifique (INRS-EAU), Université du Québec, Sainte-Foy, Canada.
Can J Microbiol. 1992 Mar;38(3):181-7. doi: 10.1139/m92-031.
A mixed culture of two fast-growing bacterial strains for heavy-metal solubilization of municipal sewage sludge has been developed. Strain VA-7 decreases the initial sludge pH (7-8.5) to a value between 4.0 and 4.5. Then, strain VA-4 begins growing and further reduces the pH to values below 2.0. The rapid decrease of sludge pH by a mixed culture through sulfur oxidation into sulfuric acid solubilizes the toxic metals (Cd 83-96%, Cr 16-54%, Cu 85-87%, Mn 91-94%, Ni 78-79%, Pb 28-46%, Zn 82-96%) to levels recommended for intensive use of residual sludge in agriculture. A study of the physiological and metabolic characteristics of these strains revealed that isolate VA-7 is a strain of Thiobacillus thioparus (ATCC 55127), while isolate VA-4 corresponds to a Thiobacillus thiooxidans (ATCC 55128). These bacterial strains possess distinctive physiological characteristics that allow them to easily grow and solubilize heavy metals in municipal sludge.
已开发出一种用于溶解城市污水污泥中重金属的两种快速生长细菌菌株的混合培养物。菌株VA - 7将初始污泥pH值（7 - 8.5）降低至4.0至4.5之间的值。然后，菌株VA - 4开始生长并将pH值进一步降低至2.0以下。通过混合培养物将硫氧化成硫酸使污泥pH值迅速下降，从而将有毒金属（镉83 - 96%、铬16 - 54%、铜85 - 87%、锰91 - 94%、镍78 - 79%、铅28 - 46%、锌82 - 96%）溶解至农业中大量使用剩余污泥所推荐的水平。对这些菌株的生理和代谢特性的研究表明，分离株VA - 7是排硫硫杆菌菌株（ATCC 55127），而分离株VA - 4对应于氧化硫硫杆菌（ATCC 55128）。这些细菌菌株具有独特的生理特性，使其能够在城市污泥中轻松生长并溶解重金属。
