方铅矿与黄铜矿浮选分离中方铅矿抑制剂研究进展

方铅矿和黄铜矿的浮选分离主要采用抑铅浮铜工艺。但目前铅铜分离效率低,方铅矿和黄铜矿的分离仍然是选矿领域的难点。高效、有选择性的方铅矿抑制剂已经成为一个研究热点,近年来国内相继研发出一批新型的抑制剂。针对方铅矿抑制剂进行总结,根据抑制剂的化学结构和应用方式,把抑制剂分为无机抑制剂、有机抑制剂、组合抑制剂、新型抑制剂四类。总结了近年来四类抑制剂的药剂结构特点、分选效率、作用机理,并对抑制剂的未来发展方向进行展望。     

Adsorption of copper sulphate on PGM-bearing ores and its influence on froth stability and flotation kinetics

Copper sulphate is used as an activator in the flotation of base metal sulphides as it promotes the interaction of collector molecules with mineral surfaces. It has been used as an activator in certain platinum group mineral (PGM) flotation operations in South Africa although the mechanisms by which improvements in flotation performance are achieved are not well understood. Some investigations have suggested these changes in flotation performance are due to changes in the froth phase rather than activation of minerals by true flotation in the pulp zone. In the present study, the effect of copper sulphate on froth stability was investigated on two PGM containing ores, namely Merensky and UG2 (Upper Group 2) ores from the Bushveld Complex of South Africa. Froth stability tests were conducted using a non-overflowing froth stability column. Zeta potential tests and ethylenediaminetetraacetic acid (EDTA) tests were used to confirm the adsorption of reagents onto pure minerals commonly found in the two ores. The results of full-scale UG2 concentrator on/off copper sulphate tests are also presented. The UG2 ore showed a substantial decrease in froth stability in the order of reagent addition: no reagents > copper > xanthate > copper + xanthate, while Merensky ore showed a slight decrease. It was shown through zeta potential measurements that copper species were to be found on plagioclase, chromite, talc and pyrrhotite surfaces and through EDTA extraction that this copper was in the form of almost equal amounts of Cu(OH)₂ and chemically reacted copper ions on the Merensky and UG2 ore surfaces. In certain cases, the presence of copper sulphate and xanthate substantially increased the recovery, and therefore the implied hydrophobicity, of pure minerals in a frothless microflotation device. It was, therefore, proposed that increases in hydrophobicity beyond an optimum contact angle for froth stability, were the cause of instabilities in the froth phase and these were found to impact grade and recovery in a full-scale concentrator. Differences in the extent of froth phase effects between the different ores can be attributed to differences in mineralogy.     

TL-1和BK510在铜锌分离提高锌浮选指标中的应用研究

为解决现场生产中铜锌浮选指标低、铜锌分离困难等问题进行了本次试验研究,该矿石属于硫化铜锌矿。试验采用自主研发的铜捕收剂TL-1及黄铁矿抑制剂BK510,获得的试验指标为:铜精矿中铜品位22.86%,铜回收率93.68%,含锌3.96%;锌精矿中锌品位48.77%,锌回收率94.72%,含铜0.092%。试验结果表明,捕收剂TL-1对铜矿物具有良好的选择性和捕收能力,新型抑制剂BK510对黄铁矿具有有效的抑制作用。     

Zn2+-Mg2+-H2O系中和沉锌热力学分析及应用

湿法炼锌废电解液在冷冻结晶除镁时会生成大量ZnSO₄?7H₂O和MgSO₄?7H₂O组成的结晶产物,采用中和水解法实现结晶产物中锌、镁的分离回收。根据配位化学热力学平衡原理,绘制了298K时Zn^₂₊-Mg^₂₊-H₂O系热力学平衡图。结果表明：在pH为6.0~12.0范围内,锌离子优先沉淀析出;pH=8.0时,Zn(OH)_2(s)的条件溶度积pKs=15.6,溶液中[Zn]_T≤1.0×10^_-5mol/L。实验数据表明,在温度60℃、pH为7.0、反应时间80min的最优条件下,锌沉淀率达到100%,镁不沉淀;硫酸镁溶液经蒸发结晶得到MgSO₄?6H₂O,沉锌产物经稀硫酸浸出获得硫酸锌溶液和石膏产品。     

辽宁海城某菱镁矿难选原因分析及浮选研究

采用ZEISS Sigma500扫描电镜和矿物自动分析系统(AMICS),对辽宁海城和大石桥菱镁矿进行工艺矿物学对比分析,研究得出海城菱镁矿脉石矿物种类复杂,且矿物嵌布粒度细是难选主要原因;菱镁矿与脉石矿物连生体较多,且包裹严重是难选的另一主要原因.针对海城难选菱镁矿,研发了有效捕收剂,采用反正浮选流程,取得了较好的技术指标,对低品位难选菱镁矿有效利用具有重要意义.     

新型抑制剂对高密度废钻井液中重晶石浮选行为及机理研究

为提升油气井高密度废钻井液中重晶石回收率,以川南地区页岩气井离心机排渣口高密度废钻井液为研究对象,采用反浮选工艺脱除低密度固相,研究了新型抑制剂结冷胶对高密度废钻井液中重晶石与低密度固相浮选行为的影响,设计了相应的回用工艺,通过润湿性测试及Zeta电位测试探究了相应的作用机理。结果表明,采用“一粗二精一扫”浮选工艺,十二烷基硫酸钠用量为700g/t,结冷胶用量为700g/t,可得到综合回收率为84.99％,综合品位≥95％,重晶石密度≥4.2g/cm3^{的重晶石精矿。润湿性及}Zeta电位测试分析表明：结冷胶与重晶石之间以氢键形式进行吸附,并可阻碍后续十二烷基硫酸钠的吸附,而对低密度固相几乎不发生吸附,改善了重晶石与低密度固相亲疏水性而最终分离。