研究了氧化亚铁硫杆菌LX5(Thiobacillus ferrooxidans LX5)、氧化硫硫杆菌TS6(Thiobacillus thiooxidans TS6)和耐酸性酵母菌R30(Rhodowrulas p.R30)对重金属铬(Cr^3+)的耐受性.结果表明,700mg/L的Cr^3+对硫杆菌LX5、TS6的生长和氧化活性影响不大,但Cr^3+浓度大于500mg/L时明显抑制酵母菌R30的生长.酵母菌R30与硫杆菌LX5和TS6复合能明显加速污泥淋滤的进程,最佳复合比为酵母菌R30接种量2.0%,硫杆菌LX5和TS6接种量10%.分别用含酵母菌R30数量为10^4个/mL和10^2个/mL的酸化污泥作接种物进行污泥淋滤,发现淋滤过程中pH值下降的速度没有明显差异,而在淋滤起始时添加2.0%的酵母菌R30,则淋滤反应提前36h结束,由此可见,在其它条件相同的污泥淋滤中.污泥中所含耐酸性酵母菌的数量是加快淋滤的关键.
The tolerance of Thiobacillusferrooxidans LXS, Thiobacillus thiooxidans TS6 and Rhodotorula sp, R30 to Cr^3+. ions and removal efficiency of metal in sludge by bioleaching through the combination of the above three strains were explored. The effect on the growth and oxidative activity of T. ferrooxidans LX5 and T. thiooxidans TS6 could be neglected when the Cr^3+ concentration was no more than 700mg/L, a common concentration range found in tannery sludge bioleaching system. However, over 500mg/L of Cr^3+ clearly restrained the growth of Rhodotorula sp. R30. In the batch trial of tannery sludge bioleaching, with the combination of strain LX5, TS6 and R30, the time of bioleaching could be apparently shortened. The optimum inoculation ratio were 2.0% for Rhodotorula sp. R30 and 10% for T. ferrooxidans LX5 and T. thiooxidans TS6. Treating tannery sludge with bio-acidified sludge containing 10^4/mL and 10^2/mL yeast R30 as inoculum exhibited that the bioleaching efficiency was not obviously higher in the former treatment than the latter treatment. With inoculation of 2.0% yeast R30 in the beginning of bioleaching, the period of bioleaching could be apparently shortened to 36 hours. It was suggested that for improving bioleaching efficiency inoculating 2.0% of yeast R30 (10^8 cell/mL) in the treated sludge was important in the initial phase of bioleaching.