膜法盐湖卤水提锂工艺研究

Lithium Technology Research of Salt Lake Brine by Membrane

采用两级纳滤膜去除盐湖卤水中的Mg2+和Ca2+,并用反渗透膜对卤水进行浓缩,考察了膜型号、压力对膜通量以及Mg2+和Ca2+截留率的影响,结果表明,NF-1膜比NF-2膜更适合于卤水提锂过程,操作压力为2.5 MPa,浓缩倍数为8倍时,Li+的回收率最高;二级纳滤过程中浓缩倍数越大,Li+的回收率越高,综合通量和回收率,浓缩倍数为12倍效果较好。

The two- stage nanofiltration membrane was used to remove Mg2 ＋and Ca2 ＋of brine and reverse osmosis membrane was used to concentrate the brine. The effect of membrane model and pressure to the membrane flux and the rejection of Mg2 ＋and Ca2 ＋were investigated. The result showed that NF- 1 membrane was more suitable than NF- 2 membrane in the extraction of process of lithium from brine,which Li＋recovery rate was the highest when the operating pressure was 2. 5 MPa and the concentration ratio was 8 times. The recovery rate of Li＋increased with the increase of cycles of concentration and the concentration ratio times of 12 was the best.