KemEcal 4968凝聚剂对铀溶液中硅的脱除  

Removal of Silica from Uranium Solutions by KemEcal 4968 Coagulant

作　　者：黎晓 LI Xiao(CGN Uranium Development Co.,Ltd.,Beijing 100048,China)

机构地区：[1]中广核铀业发展有限公司,北京100048

出　　处：《有色金属（冶炼部分）》2024年第12期74-79,156,共7页Nonferrous Metals（Extractive Metallurgy)

摘　　要：铀矿酸法水冶采用浓硫酸浸铀,矿石中的硅酸盐随同浸出后在浸出液中形成硅的累积,对离子交换和溶剂萃取工艺造成不利影响。采用一种新型聚羧酸凝聚剂KemEcal 4968,分别以30、70、140 mg/L的用量,对中广核纳米比亚湖山铀矿浸出澄清液(PLS)和浸出矿浆(LDS)的硅进行脱除试验。结果表明,30~140 mg/L用量KemEcal 4968凝聚剂对PLS溶液除硅率可达42%~62%,而对LDS除硅率只有11%;KemEcal 4968絮凝除硅过程中不会造成体系铀、铁组分的损失;PLS除硅残留KemEcal 4968对逆流倾析浓密机组(CCD)固体沉降速率和上清液浊度影响较小。KemEcal 4968凝聚剂是该矿山较好的除硅备选试剂。综合考虑除硅效果,兼顾避免KemEcal 4968凝聚剂过量残留,以及过多硅被沉淀会造成CCD底流密度增加而影响泵送性能,建议KemEcal 4968凝聚剂用量采用30 mg/L为宜。Uranium ore acid hydrometallurgy uses concentrated sulfuric acid to leach uranium element from the ore,and the silicate in the ore forms an accumulation of silica in the leach solution after being leached accompanying other substances,which adversely affects the ion exchange and solvent extraction processes.A new type of polycarboxylic acid coagulant KemEcal 4968 was used to remove silicon from the leaching solution(PLS)and leaching slurry(LDS)of CGN Namibia's Husab Uranium Mine at the dosage of 30,70 and 140 mg/L,respectively.The results show that the silica removal rate of KemEcal 4968 coagulant at the dosage of 30—140 mg/L is 42%—62% for PLS solution,but only 11% for LDS solution;KemEcal 4968 does not cause the loss of uranium and iron components in the system during the process of silicon removal;The effect of residual KemEcal 4968 coagulant in the PLS has little effect on solid settling rate and turbidity of supernatant of counter current decant(CCD).KemEcal 4968 coagulant is a good alternative reagent for silica removal in this mine.Considering the effect of removing silicon and avoiding excessive residue of KemEcal 4968 coagulant,as well as too much silicon precipitating will increase the density of CCD underflow and affect the pumping performance,it is recommended that the dosage of KemEcal 4968 coagulant should be 30 mg/L.

关 键 词：KemEcal 4968 凝聚剂 脱硅 聚羧酸 铀矿 酸浸 

分 类 号：TL212.12[核科学技术—核燃料循环与材料]