固定床生物反应器模拟溶浸采铀吸附尾液中Fe2+的氧化试验

摘要

以活性炭作载体固定嗜酸氧化亚铁硫杆菌,构建固定床生物反应器,模拟溶浸采铀矿山吸附尾液全Fe浓度和溶液pH条件,对生物反应器氧化Fe2+工艺参数进行了试验研究.结果表明:活性炭作载体比无载体时生物反应器氧化Fe2+速率增加了1.4倍,由0.5 g· L-1·h-1增大至1.2g·L-1·h-1;生物反应器运行过程中溶液中全Fe因生成铁钒而不断消耗,需要定期清理反应器中的铁矾和补充FeSO4以保持溶液中全Fe浓度；生物反应器最优的操作条件是:底部通气,Fe2+浓度为5g·L-1时,溶液流量为1.2～1.4 L·h-1；Fe2+浓度为1g·L-1时,溶液流量为5.4L·h-1.%The packed bed bioreactor was designed and set up, active carbon was selected as carrier to immobilize Acidithiobacillus ferrooxidans (A.f). The process parameters of oxidizing ferrous were investigated by simulating ferrous concentration and solution pH value in uranium mine in bioreactor. The results showed that the ferrous oxidation rate could increase 1. 4 times from 0. 5 g · L-1 · h-1 to 1. 2 g · L-1 · h-1 with active carbon carrier. Iron in solution was consumed due to formation of NH4Fe3 (SO4)2 (OH )6 during operation. It ' s necessary to add ferrous periodically in order to keep certain iron concentration in solution and clean up NH4Fe3 (SO4)2 (OH)6 in bioreactor. The optimum operation condition of bioreactor was ventilation from bottom, ferrous concentration keeping 5 g · L-1 and solution flux keeping 1. 2-1. 4 L ·h-1 or ferrous concentration keeping 1 g · L-1 and solution flux keeping 5. 4 L ·h-1.