锂辉石矿浮选基础理论与工艺研究

发布时间：2018-08-07 20:17

【摘要】：锂辉石是目前我国提取锂资源的主要硅酸盐矿物,该类矿石主要分布于花岗伟晶岩中,其脉石矿物主要为长石和石英。在选矿过程中,常采用“三碱两皂”的药剂制度进行浮选分离。锂辉石浮选时“碱”及“皂”的用量以及浮选矿浆中Ca2+、OH-和CO32-的浓度都是影响浮选指标的重要因素。此外,在实际矿石浮选过程中,锂辉石表面常受风化污染及矿浆中矿泥影响,其可浮性变差,且矿浆中溶盐离子(Fe3+、Ca2+、Mg2+)不仅能活化锂辉石,同时也活化脉石矿物,从而降低锂辉石的浮选分离效果。此外,锂辉石矿石浮选实践中产生大量的浮选尾矿(主要矿物成分为长石和石英),实现尾矿中长石与石英的综合回收,对于矿产资源综合开发利用具有重要意义。针对这些问题,本论文对不同条件下锂辉石、长石及石英的可浮性差异,以及矿物与捕收剂的作用机理进行了较系统研究,并对实际矿石进行了选矿试验,主要的研究内容及结果如下。研究内容包括考察阴离子捕收剂对锂辉石、长石和石英的浮选行为的影响,揭示三种矿物的浮选规律;考察Fe3+、Ca2+、Mg2+对锂辉石、长石和石英的活化作用及Na2CO3对三种矿物的抑制作用。研究开展了单矿物浮选试验、人工混合矿浮选分离试验以及实际矿石浮选试验。在此基础上,采用多种现代分析测试技术,结合理论分析,对该体系中捕收剂、金属离子、Na2CO3与这三种矿物间的作用机制进行了系统的研究。单矿物浮选试验结果表明,Na OL对锂辉石、长石和石英的捕收性能并不强;Fe3+、Ca2+、Mg2+对锂辉石、长石和石英均有较强的活化作用;Na2CO3对三种矿物均有一定的抑制作用。Fe3+最佳活化p H值为7左右,少量的Fe3+可使锂辉石和石英得到很好的活化,而对长石活化性能较差。Ca2+最佳活化p H值为12.5,Ca2+需要较大的用量才能使三种矿物活化充分。Mg2+最佳活化p H值为10,Mg2+对锂辉石、长石和石英的活化无选择性。Na2CO3对受Fe3+、Ca2+活化的长石和石英选择性抑制,而对受Mg2+活化的三种矿物选择抑制性效果较差。采用Fe3+、Ca2+、Mg2+为活化剂、Na2CO3为抑制剂,Na OL为捕收剂进行人工混合矿浮选分离试验,结果表明三种活化剂对锂辉石、长石和石英均有一定的活化作用,Na2CO3对受Fe3+活化的三种矿物的浮选分离效果最佳。采用Fe3+作活化剂时,Na2CO3为抑制剂,Na OL为捕收剂时,当混合矿中锂辉石、长石和石英矿物质量比为1:1:1时,获得的泡沫产品Li2O品位为6.42%;当混合矿中锂辉石、长石和石英矿物质量比为1:2:2时,获得的泡沫产品Li2O品位为5.31%。机理研究分析结果表明,锂辉石、长石和石英经Fe3+、Ca2+、Mg2+活化后表面动电位发生正移,Na2CO3通过改变三种矿物表面电性,实现对锂辉石、长石和石英的选择性抑制。红外光谱分析表明,活化后的矿物与Na OL作用后,Na OL与矿物表面发生了化学吸附。XPS分析还表明,经Ca2+或Mg2+作用后锂辉石表面Li元素结合能发生了较大幅度化学位移,矿物表面Ca、Mg元素丰度增加;活化后的锂辉石再与Na OL作用后其表面Li、Ca及Mg元素结合能都发生了较大的化学位移,这也说明了矿物表面与Na OL发生了化学吸附。实际矿石浮选试验中,因矿石风化严重和浮选用水中含有一定的Fe3+、Ca2+及Mg2+,采用复配的捕收剂作为捕收剂,浮选过程中不添加任何金属离子活化,从含Li2O 1.30%的原矿可获得Li2O品位为5.96%、回收率达84.59%的锂辉石精矿,浮选尾矿在酸性条件下采用氢氟酸浮选分离长石和石英,获得了Na2O、K2O品位合量为11.59%、回收率为65.83%(对锂辉石浮选尾矿)的长石精矿及Si O2含量为98.84%的石英精矿,各矿物得到有效分离,实现了该锂辉石矿的的综合利用。
[Abstract]:Spodumene is the main silicate mineral for the extraction of lithium resources in China. The ore mainly distributes in granitic pegmatite and its gangue minerals are mainly feldspar and quartz. In the process of beneficiation, the "three alkali two soap" agent system is often used for flotation separation. The amount of "alkali" and "soap" in the flotation of spodumene and in the flotation pulp The concentration of Ca2+, OH- and CO32- is an important factor affecting the flotation index. In addition, in the process of actual flotation, the surface of spodumene is often affected by weathering and mineral mud in the pulp. The floatability of the pulp becomes worse, and the salt ions (Fe3+, Ca2+, Mg2+) in the pulp can not only activate the spodumene, but also activate the gangue minerals, thus reducing the spodumene. In addition, a large amount of flotation tailings (main mineral components are feldspar and quartz) are produced in the flotation practice of spodumene ore, and the comprehensive recovery of feldspar and quartz in the tailings is of great significance for the comprehensive exploitation and utilization of mineral resources. The floatability difference and the mechanism of mineral and collector's action are systematically studied, and the ore dressing experiment of the actual ore is carried out. The main contents and results are as follows. The study includes the effect of anionic collector on the flotation behavior of spodumene, feldspar and quartz, and reveals the flotation rules of the three minerals; the investigation of Fe3+, Ca 2+, Mg2+ on the activation of spodumene, feldspar and quartz and the inhibition of Na2CO3 on three minerals. A single mineral flotation test, a flotation separation test of artificial mixed ore and a practical ore flotation test were carried out. On the basis of this, a variety of modern analysis and testing techniques were used, and combined with theoretical analysis, the collector and metal in this system were separated from the metal. Na2CO3 and the mechanism of the interaction between the three minerals have been systematically studied. The single mineral flotation test results show that the collection performance of Na OL is not strong for spodumene, feldspar and quartz; Fe3+, Ca2+ and Mg2+ have a strong activation effect on spodumene, feldspar and quartz; Na2CO3 has a certain inhibitory effect on the three minerals and.Fe3+ is the best activation P. The H value is about 7, a small amount of Fe3+ can make a good activation of spodumene and quartz, while the best activation P H value for the poor activation of feldspar.Ca2+ is 12.5, and Ca2+ needs a larger amount to make the three mineral activation fully.Mg2+ the best activated P H value 10, Mg2+ for the activation of spodumene, feldspar and quartz.Na2CO3 against Fe3+. The selective inhibition of activated feldspar and quartz has a poor inhibitory effect on the three minerals activated by Mg2+. Using Fe3+, Ca2+, Mg2+ as activator, Na2CO3 as an inhibitor and Na OL as a collector, the flotation separation test of artificial mixed ore is carried out. The results show that three activators have certain activation effect on spodumene, feldspar and quartz, Na2CO 3 the flotation separation effect of three minerals activated by Fe3+ is the best. When Fe3+ is used as a activating agent, Na2CO3 is the inhibitor and Na OL is the collector. When the mass ratio of spodumene and feldspar and quartz is 1:1:1, the Li2O grade of the foam product is 6.42%, and the mass ratio of spodumene and feldspar and quartz in the mixed ore is 1:2:2. The results of the study on the Li2O grade of the foam products obtained by 5.31%. show that the surface dynamic potential of the spodumene, feldspar and quartz is shifted positively after the activation of Fe3+, Ca2+ and Mg2+. By changing the surface electrical properties of three minerals, Na2CO3 can inhibit the selection of spodumene, feldspar and quartz. The infrared spectrum analysis shows that the activated mineral and Na OL are found. After the action, Na OL and the chemical adsorption.XPS analysis on the surface of the mineral also showed that after the action of Ca2+ or Mg2+, the binding energy of the Li element on the surface of the spodumene had a large chemical shift, the mineral surface Ca, the abundance of Mg elements increased, and the activated Spodumene after the action of the Na OL was Li, and the binding energy of the Ca and the elements both had greater chemistry. Displacement, which also shows that the mineral surface and Na OL have a chemical adsorption. In the actual flotation test, the ore weathering is serious and the flotation selection water contains certain Fe3+, Ca2+ and Mg2+, and the compound collector is used as collector. The flotation process does not add any metal ion activation, and the Li2O grade can be obtained from the original ore containing Li2O 1.30%. 5.96%, the recovery rate of spodumene concentrates is 84.59%. Flotation tailings are separated by hydrofluoric acid by flotation separation of feldspar and quartz under acidic conditions. The Na2O, K2O grade is 11.59%, the recovery rate is 65.83% (for the spodumene flotation tailings) and the Si O2 content of the quartz concentrate is 98.84%, the minerals are effectively separated and the lithium glow has been realized. The comprehensive utilization of stone ore.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD97

【参考文献】