分散剂及工艺优化对吉林某低品位硅藻土提纯的影响

吉林临江低品位硅藻土属高烧失三级硅藻土，脉石矿物主要为石英和钠长石。为提高该硅藻土纯度，对其进行了浮选分散剂选择试验，并对最佳浮选条件下所得浮选精矿进行了焙烧-酸浸试验。结果表明，在矿浆温度为40 ℃、pH为9、十二胺为捕收剂条件下浮选，三聚磷酸钠作为分散剂时浮选指标最佳。以三聚磷酸钠作为分散剂、十二胺为捕收剂，经1粗2精浮选获得了SiO₂品位为79.38%、Al₂O₃品位为5.04%的硅藻土浮选精矿。该浮选精矿在600 ℃条件下焙烧1 h后，在室温条件下采用20%的硫酸浸出1.5 h，获得了SiO₂品位为89.57%、Al₂O₃品位为4.77%、Fe₂O₃品位为0.71%的硅藻土精矿，达到了一级土的标准。

Effects of Dispersants and Process Optimization on Purification of a Low-grade Diatomite in Jilin

The low-grade diatomite of Linjiang County，Jilin Province，is grade-three diatomite with high burning loss，and gangue minerals are mainly quartz and albite.Dispersant selection tests ate carried out in order to purification the diatomite，as well as roasting-acid leaching tests on the flotation concentrate.The results showed that the flotation index is optimum when using sodium tripolyphosphate（STPP) as dispersant under pH 9，slurry is 40 ℃ and lurylamine as collector.By STPP as dispersant solvent，through one roughing and two cleaning flotation operation，concentrate with 79.38% SiO₂，5.04%Al₂O₃ is obtained.And the concentrate of flotation was roasted for 1 h at temperature of 600 ℃，and leaching for 1.5 h using 20% sulfuric acid as solvent.Finally，diatomaceous concentrate with 89.57% SiO₂，4.77% Al₂O₃，0.71% Fe₂O₃ is obtained，which can meets the standard of top-grade diatomite.