【作者】 汤佩徽；

【导师】 张国范；

【作者基本信息】 中南大学 ， 矿物加工工程， 2011， 硕士

【摘要】 磷灰石在浮选矿浆中的表面溶解会改变矿物的表面性质和浮选矿浆的化学环境。硅-钙质磷矿中主要含有硅质脉石(以石英为代表)和钙质脉石(以白云石为代表)两类。由于石英在碱性条件(pH大于10以后)下,极易被Ca2+活化,磷灰石溶液中溶解的Ca2+对磷灰石和石英的分离将产生不利的影响。论文研究了磷灰石和石英的基本浮选行为,以及金属Ca2+和各种抑制剂对磷灰石和石英分离的影响；系统考查了pH调整剂种类、Ca2+离子以及水玻璃对磷灰石和石英浮选行为的影响机理；并通过动电位测试、光电子能谱及浮选溶液化学,明确了磷灰石表面的活性物质及在碳酸钠体系中石英活化的作用原理。得到以下研究结果：1、磷灰石的可浮性优于石英。采用Na2CO3作为pH调整剂可提高磷灰石的可浮性,增大磷灰石和石英的可浮性差异。在碱性介质中,磷灰石表面活性物质是CaHPO4,当添加Na2CO3后,磷灰石饱和溶液中HPO42-组分的含量增加,即磷灰石表面活性物质增加,回收率也因此增加。2、浮选过程中添加金属Ca2+,在pH大于10(Na2CO3或NaOH)以后,石英回收率迅速增加,石英被活化的机理在于新生成的CaCO3沉积在表面；而在Na2CO3调浆体系中,加入金属Ca2+对磷灰石的影响较大,回收率有所下降,在NaOH调浆体系中,对磷灰石可浮性几乎无影响。3、在研究抑制剂种类对磷灰石和石英浮选分离影响的过程中,发现水玻璃的选择性明显要优于古尔胶、木质素磺酸钠、糊精和六偏磷酸钠。即使是被Ca2+活化过的石英,水玻璃依然对其有强烈的抑制作用,而对磷灰石几乎无影响。因此,在碱性条件下对磷灰石和石英进行浮选分离时,选择Na2CO3作为pH调整剂,水玻璃作为抑制剂,效果理想。更多还原

【Abstract】 The surface dissolution of apatite in pulp will change its surface properties and the solution chemistry environment. Silicon-calcium phosphate rock contains mainly siliceous gangue (quartz as the representative) and calcareous gangue (represented by dolomite). Since in alkaline conditions (pH> 10), quartz is easy to be activated by Ca2+, and Ca2+ dissolved in apatite solution has a negative impact on the separation of apatite and quartz. The thesis studied the basic flotation behavior of apatite and quartz, and the influence by Ca2+ and various inhibitors on the separation of apatite and quartz. And investigate the types of pH regulator, and the mechanism of the impact on the flotation behavior by Ca2+ and the water glass. And by potentiodynamic tests, X-ray photoelectron spectrometric and flotation solution chemistry, reveals the substances on apatite surface and the principle of the activation of quartz in the sodium carbonate system. Get the following results:1. The floatability of apatite is superior to quartz. Using Na2CO3 as the pH regulator can improve the floatability of apatite, and increase the floatability difference between apatite and quartz. In alkaline medium, the active substance on apatite surface is CaHPO4. When adding Na2CO3 solution, the content of HPO42-component increases in the apatite saturated solution, in other words, the active substance increased on surface, therefore the recovery increased.2. Adding Ca2+ in flotation process at pH>10 (Na2CO3 or NaOH), the recovery of quartz increases rapidly. The mechanism of activation is that the new generation of CaCO3 deposites on the quartz surface. In the system of Na2CO3 as pH regulator, the recovery of apatite has dropped after adding Ca2+, while in the system of NaOH as pH regulator system, the floatability of apatite almost have not been affected.3. In the study of the impact of inhibitor species on flotation separation of apatite and quartz, water glass was found to be superior to guar gum, lignin sulfonate, dextrin, and sodium hexametaphosphate. Even as to quartz activated by Ca2+, water glass still has a strong inhibitory effect on its, but almost no effect on the apatite.Thus, under alkaline conditions, we can select Na2CO3 as the pH regulator, water glass as inhibitor in the flotation separation of apatite and quartz, and the results are satisfactory.更多还原