以甘蔗渣为缓释碳源及载体,负载硫酸盐还原菌(SRB)处理含低浓度Cu^(2+)离子的模拟矿山淋滤水,研究了缓释碳源、p H、ORP、SO2-4、COD等对矿山淋滤水中Cu^(2+)去除效果的影响,并探讨了处理过程中铜元素的形态及归趋模式。结果表明:在处理过程中p H呈现缓慢升高趋势,ORP全部降至-100 m V以下;硫酸根还原率可达92.4%;甘蔗渣作为缓释碳源释放稳定,COD可稳定保持200~300 mg/L之间;负载在甘蔗渣载体上的菌群可耐受高浓度Cu^(2+)的毒性抑制,并利用缓释碳源甘蔗渣释放出的小分子物质将硫酸根持续还原;至实验期结束,20 mg/L的Cu^(2+)浓度降至0.5 mg/L以下,较高浓度的Cu^(2+)拟通过多级反应器串联进行逐级去除;SO2-4和Cu^(2+)的反应速率比表明,SRB每还原约15 mg SO2-4,就有1 mg Cu^(2+)得到去除;Cu^(2+)主要是以硫化物的形式得以去除。
A low concentration of copper( Cu~(2+)) in synthetic leaching wastewater was treated with sulfatereducing bacteria( SRB) using sugarcane bagasse as the carbon source and carrier. The impacts of p H,oxidation reduction potential( ORP),the concentration of sulfate( SO2-4),and the chemical oxygen demand( COD)were analyzed and the form of the precipitate was also investigated. The results showed that the p H values slowly increased,the values of ORP all decreased to below- 100 m V,and the percentage of SO2-4reduction could reach 92. 4% during the period. In addition,the COD was maintained in the range of 200 to 300 mg / L. The microflora in the system had a tolerance to the inhibition of the high concentration of Cu~(2+),and the SRB could reduce sulfate by small molecules that were produced by the biological degradation of the bagasse. At the end of experiment,the concentration of Cu~(2+)was reduced from 20 mg / L to below 0. 5 mg / L,while the high concentration of Cu~(2+)could be removed by several multi-stage reactors in series. Moreover,the reaction rates of SO2-4and Cu~(2+)indicated that 1 mg Cu~(2+)could be removed when SRB reduced 15 mg of SO2-4. Cu~(2+)was eventually removed mainly as sulfide.