GENOCOV Research Group, Departament d'Enginyeria Química, Biològica i Ambiental. Escola d'Enginyeria, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
GENOCOV Research Group, Departament d'Enginyeria Química, Biològica i Ambiental. Escola d'Enginyeria, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
J Hazard Mater. 2021 May 5;409:124944. doi: 10.1016/j.jhazmat.2020.124944. Epub 2020 Dec 24.
Bioelectrochemical systems provide a promising tool for the treatment of acid mine drainage (AMD). Biological sulphate reduction powered with electrical energy consumes acidity and produces sulphide, which can precipitate metals. However, the produced sulphide and the changes in pH resulting from the biological processes affect the efficiency and the environmental impacts of this treatment significantly. In this work, the effects of pH and sulphur speciation on the sulphate reduction rate (SRR) and comprehensive AMD treatment were evaluated in two-chamber microbial electrolysis cells at a cathode potential of -0.8 V vs. NHE. The increase of initial sulphate concentration from below 1000 mg to above 1500 mg S-SO/L increased SRR from 121 ± 25 to 177 ± 19 mg S-SO/L/d. SRR further increased to 347 mg S-SO/L/d when the operation mode was changed from batch to periodical addition of sulphate and acidity (363 mg S-SO/L/d and 22.6 mmol H/L/d, respectively). The average SRR remained above 150 mg S-SO/L/d even at pH above 8.5 and with the total dissolved sulphide concentration increasing above 1300 mg S-TDSu/L. Operation at pH above 8 enabled the recovery of over 90% of the sulphur as dissolved sulphide and thus assisted in minimising the formation and release of toxic HS.
生物电化学系统为处理酸性矿山排水（AMD）提供了一种很有前景的工具。利用电能进行生物硫酸盐还原会消耗酸度并产生硫化物，从而可以沉淀金属。然而，所产生的硫化物以及生物过程引起的 pH 值变化会显著影响这种处理的效率和环境影响。在这项工作中，在阴极电位为 -0.8 V 相对于 NHE 的双室微生物电解池，评估了 pH 值和硫形态对硫酸盐还原率（SRR）和综合 AMD 处理的影响。初始硫酸盐浓度从低于 1000 mg 增加到高于 1500 mg S-SO/L 时，SRR 从 121 ± 25 增加到 177 ± 19 mg S-SO/L/d。当操作模式从分批改为周期性添加硫酸盐和酸（分别为 363 mg S-SO/L/d 和 22.6 mmol H/L/d）时，SRR 进一步增加到 347 mg S-SO/L/d。即使在 pH 值高于 8.5 且总溶解硫浓度高于 1300 mg S-TDSu/L 时，平均 SRR 仍保持在 150 mg S-SO/L/d 以上。在 pH 值高于 8 时运行，可以回收超过 90%的硫作为溶解的硫化物，从而有助于最小化有毒 HS 的形成和释放。
