Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China.
Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China.
Bioresour Technol. 2018 Oct;266:45-50. doi: 10.1016/j.biortech.2018.06.048. Epub 2018 Jun 19.
Anaerobic digestion of the heavy metal-contaminated rice straw inoculated with waste activated sludge was carried out through an orthogonal array. The results indicated that the digestion process was optimized with an inoculum to substrate ratio (I/S) of 0.25, a total solid (TS) content of 5%, and an initial pH of 7.0, with corresponding total biogas and methane yields of 745.4 and 285.2 mL/g VS, respectively. Under the optimized conditions, the bioleaching percentages of Cd and As in the biomass were 13.13% and 42.90%, respectively. According to range analysis, the biogas yield, methane yield, and bioleaching percentages of Cd and As in the biomass significantly decreased with an increase in TS content from 5% to 15%. The results suggested that anaerobic digestion with waste activated sludge was feasible for achieving both biogas production and bioleaching of heavy metals from contaminated rice straw.
采用正交试验对接种了废活性污泥的重金属污染稻草进行了厌氧消化。结果表明，在接种量与底物比（I/S）为 0.25、总固体（TS）含量为 5%、初始 pH 值为 7.0 的条件下，消化过程得到了优化，相应的总沼气和甲烷产量分别为 745.4 和 285.2 mL/g VS。在优化条件下，生物质中 Cd 和 As 的生物浸出率分别为 13.13%和 42.90%。根据范围分析，随着 TS 含量从 5%增加到 15%，沼气产量、甲烷产量以及生物质中 Cd 和 As 的生物浸出率显著降低。结果表明，利用废活性污泥进行厌氧消化，既能生产沼气，又能从污染的稻草中生物浸出重金属。
