(東華理工大學(xué) 核資源與環(huán)境國家重點(diǎn)實(shí)驗(yàn)室，南昌 330013)
摘 要: 隨著對天然鈾需求的不斷增加，低品位及難浸鈾礦的開采日漸受到關(guān)注，微生物溶浸是解決此類鈾資源開發(fā)的重要技術(shù)之一。浸鈾工藝主要為堆浸和地浸，大量的室內(nèi)及野外微生物浸鈾試驗(yàn)研究表明，微生物浸鈾技術(shù)應(yīng)用于工業(yè)生產(chǎn)是可行的。浸礦微生物經(jīng)過誘導(dǎo)馴化，其耐受性可以得到明顯提升，能適應(yīng)高氟鈾礦石、低溫以及強(qiáng)酸等環(huán)境條件，如可在氟含量為2~3.98 g/L的尾液中良好生長，在8~10 ℃的低溫條件下能保持良好的活性，也能較好地生長于pH為1.2~2.0甚至低至0.6的強(qiáng)酸環(huán)境中。馴化誘導(dǎo)是提高菌種對浸礦環(huán)境適應(yīng)性的通常的技術(shù)途徑，采用土著菌并適當(dāng)加以馴化培養(yǎng)，往往能獲得對本土礦區(qū)適應(yīng)能力更強(qiáng)的優(yōu)良菌種。研究表明混合菌種之間存在協(xié)同作用，浸礦效果優(yōu)于單一菌種的。微生物浸鈾的間接作用是明確的，但微生物直接作用鈾礦物的觀點(diǎn)目前仍存在爭論。從微生物浸鈾機(jī)理、耐受性研究、菌種培養(yǎng)選育和微生物浸鈾技術(shù)的實(shí)踐應(yīng)用研究4個(gè)方面，對近20年的成果進(jìn)行了綜述，就微生物浸鈾尤其是在地浸方面的發(fā)展進(jìn)行了分析與展望。
關(guān)鍵字: 微生物浸鈾；浸礦機(jī)理；耐受性；菌種培養(yǎng)
（State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, China）
Abstract:With the increasing demand of natural uranium, the exploitation of low-grade or complex uranium ores has been attracting more and more attention. The biological leaching is one of the important techniques for exploitation of such uranium resources. At present, heap leaching and in-situ leaching are the main processes for uranium recovery. Numbers of laboratory experiments and field trails show that the microbial leaching is a feasible technique for industrial production of uranium from low-grade or refractory ores. The tolerance of microorganism which has been mutated and acclimated can be improved obviously, and it can be adapted to high fluorine uranium ores, low temperature and high acidity environments. For example, the acclimated bacteria can grow well in mining tails with fluorine content of 2-3.98 g/L, under the condition of low temperature of 8 ℃, and in solution of which pH is 1.2-2.0 or even in a higher acidity solution (pH is low to 0.6). Acclimation and induction are common technical ways to improve the adaptability of bacteria species to leaching environment, and indigenous bacterias often have better adaptability to native mining areas. The results also show that there is a synergistic effect between mixed strains and the leaching effect is better than that of single strain. The indirect action of microbial on uranium ore is clear, but the view of direct action of microorganism on uranium ore is still controversial. The mechanism of uranium leaching by microorganism, the study of tolerance, the breeding of bacteria and practical application research of microbial leaching uranium technology were reviewed, especially in the past 20 years. The development of bioleaching of uranium, especially in-situ leaching, was prospected.
Key words: bioleaching of uranium; mechanism of uranium leaching; microorganism tolerance; microbial strain culture
