连续的酸盐沉,微生物硫酸盐减少和在现场去除硫化,用于中性矿井排水处理
Ka Yu Cheng1, Caroline Rubina Acuña2, Anna H Kaksonen3
1CSIRO Environment, 147 Underwood Avenue, Floreat, Western Australia (WA) 6014, Australia; School of Engineering & Energy, Murdoch University, WA 6150, Australia.
The Science of the total environment
|March 9, 2024
概括
这项研究开发了一种三阶段的工艺来处理中性矿井排水,有效地去除金属,酸盐,硫酸盐和硫化. 这种创新方法实现了几乎完全的硫酸盐去除,为矿山水的整治提供了可持续的解决方案.
科学领域:
- 环境科学与工程环境科学与工程
- 水处理技术 水处理技术
- 微生物生态学 微生物生态学
背景情况:
- 中性矿井排水 (NMD) 带来了重大的环境挑战,因为它含有大量的金属,金属化物,硫酸盐,并有可能产生硫化 (H2S).
- 现有的处理方法往往难以全面清除污染物,特别是硫酸盐和H2S,因此需要创新和高效的方法.
- 露天金矿是NMD的主要来源,需要有效的补救策略来减轻生态影响.
研究的目的:
- 提出和评估一种新的,连续的三阶段工艺流程表,用于处理中性矿井排水 (NMD).
- 为了验证水晶 (HT) 沉,微生物硫酸盐减少 (MSR) 和铁溶反应屏障在去除关键NMD污染物的有效性.
- 评估每个阶段的性能和整体过程在减少金属,金属化物,酸盐,硫酸盐和H2S的性能.
主要方法:
- 实验室规模的柱子运行了140天,模拟了三阶段的处理过程:现场酸盐 (HT) 沉,低成本碳基板驱动的微生物硫酸盐减少 (MSR) 和铁盐反应屏障.
- 定期监测关键性能参数,包括污染物去除效率和H2S生成.
- 处理后的分析包括固体的元素组成和矿物阶段识别,以及使用16S rRNA基因测序对微生物群落的表征.
主要成果:
- 第1阶段 (HT沉) 有效地去除了As,B,Ba,Ca,F,Zn,Si和U,但没有酸盐或硫酸盐.
- 第二阶段 (MSR生物反应器) 实现了完全的酸盐去除和约50%的稳定硫酸盐去除 (50g-SO4 m-3 d-1),产生H2S在10g-H2S m-3d-1.
- 第3阶段 (铁溶屏障) 显示出优于对照的性能,实现了额外的99.9%的硫酸盐减少 (几乎完全去除) 和优秀的H2S去除 (>95%),将硫酸盐从2500毫克L-1降低到10毫克L-1.
结论:
- 拟议的三阶段工艺有效处理中性矿井排水,显著减少硫酸盐和消除金属,金属化物,酸盐和H2S,以满足严格的废水标准.
- 铁沉,MSR和铁盐屏障的组合为矿山水的整治提供了一个有希望和高效的方法.
- 需要进一步优化,以最大限度地减少最终废水中铁溶屏障中铁性铁的释放.
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