Ammonium sulfate ((NH4)2SO4) leaching method to extract rare earth elements (REEs) of mine has produced a large amount of NH4+-N-enriched wastewater derived from ore body, leading to many serious environmental pollution problems. This study was the first time to establish an in-situ treatment for real REEs wastewater outside and inside the ore body by an isolated indigenous microorganism. The results stated that Citrobacter sp. X-9 achieved the highest NH4+-N removal efficiency among the isolated six microbial strains. Moreover, the microbe to treat the REEs wastewater outside ore body gave the greatest NH4+-N removal efficiency under the optimized conditions in the Erlenmeyer flask (250-mL) and bioreactor (10-L). Furthermore, compared to the others’ modes, the in-situ treatment by cyclic mode with Citrobacter sp. X-9 possessed superior performance in NH4+-N removal efficiency for wastewater inside of ore body, showing that the established in-situ treatment was the potential approach for REEs wastewater purification.

中文翻译：

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利用原矿区分离的天然细菌对稀土矿山铵态氮废水进行原位净化


硫酸铵 （（NH4）2SO4） 浸出法提取矿山稀土元素 （REE），产生了大量来自矿体的富含 NH4+-N 的废水，导致许多严重的环境污染问题。这项研究是首次通过分离的原生微生物对矿体内外的真实 REE 废水进行原位处理。结果表明，柠檬酸杆菌属X-9 在分离的 6 种微生物菌株中实现了最高的 NH4+-N 去除效率。此外，在锥形瓶 （250 mL） 和生物反应器 （10 L） 的优化条件下，处理矿体外 REE 废水的微生物具有最高的 NH4+-N 去除效率。此外，与其他模式相比，用柠檬酸杆菌属循环模式进行原位处理。X-9 对矿体内废水的 NH4+-N 去除效率具有优异的性能，表明建立的原位处理是 REEs 废水净化的潜在方法。