China Nuclear Mining Science and Technology Corporation, Shijiazhuang, 050021, China.
China Nuclear Mining Science and Technology Corporation, Shijiazhuang, 050021, China.
J Environ Radioact. 2024 Jul;277:107463. doi: 10.1016/j.jenvrad.2024.107463. Epub 2024 May 29.
Seepage of uranium tailings has become a focus of attention in the uranium mining and metallurgy industry, and in-situ microbial remediation is considered an effective way to treat uranium pollution. However, this method has the drawbacks of easy biomass loss and unstable remediation effect. To overcome these issues, spare red soil around the uranium mine was used to enhance the efficiency and stability of bioremediation. Furthermore, the bioremediation mechanism was revealed by employing XRD, FTIR, XPS, and 16S rRNA. The results showed that red soil, as a barrier material, had the adsorption potential of 8.21-148.00 mg U/kg soil, but the adsorption is accompanied by the release of certain acidic and oxidative substances. During the dynamic microbial remediation, red soil was used as a cover material to neutralize acidity, provide a higher reduction potential (<-200 mV), and increase the retention rate of microbial agent (19.06 mL/d) compared to the remediation group without red soil. In the presence of red soil, the anaerobic system could maintain the uranium concentration in the solution below 0.3 mg/L for more than 70 days. Moreover, the generation of new clay minerals driven by microorganisms was more conducive to the stability of uranium tailings. Through alcohol and amino acid metabolism of microorganisms, a reducing environment with reduced valence states of multiple elements (such as S, Fe, and U) was formed. At the same time, the relative abundance of functional microbial communities in uranium tailings improved in presence of red soil and Desulfovirobo, Desulfocapsa, Desulfosporosinus, and other active microbial communities reconstructed the anaerobic environment. The study provides a new two-in-one solution for treatment of uranium tailings and resource utilization of red soil through in-situ microbial remediation.
铀尾矿的渗漏已成为铀矿冶行业关注的焦点，原位微生物修复被认为是处理铀污染的有效方法。然而，这种方法存在生物量易损失和修复效果不稳定的缺点。为了克服这些问题，利用铀矿周围的闲置红土来提高生物修复的效率和稳定性。此外，还采用 XRD、FTIR、XPS 和 16S rRNA 揭示了生物修复机制。结果表明，红土作为一种阻隔材料，具有 8.21-148.00mg U/kg 土壤的吸附潜力，但吸附伴随着一定酸性和氧化性物质的释放。在动态微生物修复过程中，红土作为覆盖材料可中和酸度，提供更高的还原电位（<-200mV），并提高微生物剂的保留率（19.06mL/d），优于没有红土的修复组。在红土存在的情况下，可使溶液中的铀浓度在 70 天以上保持在 0.3mg/L 以下。此外，微生物驱动生成的新粘土矿物更有利于铀尾矿的稳定性。通过微生物的醇和氨基酸代谢，形成了具有多种元素（如 S、Fe 和 U）还原价态的还原环境。同时，红土的存在提高了铀尾矿中功能微生物群落的相对丰度，脱硫弧菌、脱硫帽菌、脱硫孢子菌等活性微生物群落重构了厌氧环境。该研究为原位微生物修复处理铀尾矿和利用红土提供了一种新的两用解决方案。
