(1. 河海大學(xué) 淺水湖泊綜合治理與資源開發(fā)教育部重點(diǎn)實(shí)驗(yàn)室，南京 210098；
2. 河海大學(xué) 環(huán)境學(xué)院，南京 210098)
摘 要: 針對(duì)氧化亞鐵硫桿菌生物(T. f)淋濾法處理重金屬污染底泥進(jìn)行實(shí)驗(yàn)研究。采用分批搖床培養(yǎng)方法，分析生物淋濾過程中Fe2+濃度對(duì)底泥酸化、微生物生長(zhǎng)、Fe2+氧化以及底泥中重金屬溶出率的影響；借助Monod方程得到不同F(xiàn)e2+濃度下氧化亞鐵硫桿菌的最大比生長(zhǎng)速率及飽和常數(shù)；通過經(jīng)驗(yàn)方程推導(dǎo)出不同F(xiàn)e2+濃度下重金屬離子Cu2+和Zn2+的溶出速率常數(shù)。結(jié)果表明，當(dāng)Fe2+濃度由2.0 g/L增加到10.0 g/L時(shí)，氧化亞鐵硫桿菌的最大比生長(zhǎng)速率由0.126 h-1上升到0.159 h-1，飽和常數(shù)由0.881 g/L下降到0.327 g/L，重金屬的溶出速率常數(shù)與Fe2+濃度呈正相關(guān)；當(dāng)Fe2+濃度超過10.0 g/L時(shí)，氧化亞鐵硫桿菌的最大比生長(zhǎng)速率降低，而飽和常數(shù)增大。隨著Fe2+濃度的增加Fe2+氧化速率增大。綜合各個(gè)動(dòng)力學(xué)參數(shù)可知，F(xiàn)e2+濃度為10.0 g/L是生物淋濾體系的最佳底物濃度。
關(guān)鍵字: 重金屬；氧化亞鐵硫桿菌；生物淋濾；動(dòng)力學(xué)
（1. Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of
Ministry of Education, Hohai University, Nanjing 210098, China;
2. College of Environment, Hohai University, Nanjing 210098, China）
Abstract:The bioleaching kinetics of heavy metal from contaminated sediment was studied by batch experiments with Thiobacillus ferrooxidans (T. f). The effects of Fe2+ concentrations on the sediment acidification, the growth of T. f, Fe2+ oxidation, and solubilization ratio of heavy metal during the bioleaching process were investigated. Monod equation was used to derive the maximum specific growth rate and the saturation constant of the T. f with different Fe2+ concentrations. An empirical equation was also used to derive the rate constants of heavy metal ions (Cu2+ and Zn2+) solubilization with different Fe2+ concentrations. The results show that when Fe2+ concentration increases from 2.0 g/L to 10.0 g/L the maximum specific growth rate of T. f increases from 0.129 h-1 to 0.159 h-1, the saturation constant reduces from 0.881 g/L to 0.327 g/L and the rate constant of heavy metals solubilization is linearly dependent on the Fe2+ concentrations. When Fe2+ concentrations is over 10.0 g/L, the maximum specific growth rate of the T. f reduces, while the saturation constant increases. The Fe2+ oxidation rates increase with increasing the Fe2+ concentrations. Taking all the kinetics parameters into account, the optimal concentration of Fe2+ is found to be 10.0 g/L.
Key words: heavy metal; Thiobacillus ferrooxidans; bioleaching; kinetics
