选矿回水中复杂离子对磷矿浮选的影响研究

发布时间：2018-06-24 18:18

本文选题：钙镁质磷矿 + 反浮选　；参考：《贵州大学》2015年硕士论文

【摘要】：氟磷灰石属微溶性盐类矿物,其浮选除易受到自身溶解晶格离子的影响外,还会被同一浮选体系中其它盐类矿物溶解组分影响。此外,由于脂肪酸类捕收剂选择性差,对浮选中溶解离子敏感。因此,系统地研究复杂离子对磷矿浮选的影响,对选矿厂开展有针对性的废水处理及回水清洁利用具有重要的意义。本文以贵州地区两个有代表性的磷矿样为研究对象,通过浮选条件试验确定了合适的浮选工艺;利用单因素试验和正交试验考察复杂离子对磷矿反浮选指标的影响,并确定有害离子影响浮选指标的最低离子浓度;通过溶液化学计算、XRD分析、SEM分析以及表面张力测定研究复杂离子影响反浮选指标的作用机理。试验选取的两个磷矿样中有用矿物均为氟磷灰石、脉石矿物主要为白云石并含少量石英1#磷矿样中P2O5、Mg O和Si O2品位分别为28.72%、5.78%和2.11%,2#磷矿样中P2O5、Mg O和Si O2品位分别为22.67%、7.58%和4.30%。针对1#磷矿样,试验确定合适的磨矿细度为-75μm占80.67%,H2SO4和捕收剂用量分别为14 kg/t和0.6 kg/t。在此条件下,获得的精矿P2O5品位和回收率分别为35.82%和95.43%,Mg O品位为1.05%。对于2#磷矿样,试验确定合适的磨矿细度为-75μm占70.76%,H2SO4和捕收剂用量分别为18 kg/t和0.8 kg/t。在此条件下,获得的浮选指标为精矿P2O5品位33.81%、P2O5回收率87.16%、Mg O 1.20%、Si O2 5.48%、Al2O3 0.63%、Fe2O3 1.10%。将精矿滤液返回浮选后,随着滤液循环次数的增加,回水中Ca2+、Mg2+、SO42-、TP和F-浓度逐渐增加,存在离子“积累效应”;同时回水利用会对浮选指标产生影响,尤其是对精矿P2O5回收率。单一离子体系下,回水中Ca2+和Mg2+会降低精矿P2O5品位并提高精矿Mg O品位。SO42-对磷矿反浮选指标的影响较大,尤其是对精矿P2O5回收率。Ca2+和SO42-对2#磷矿样浮选的影响大于1#磷矿样。PO43-和F-对浮选指标影响较小。Ca2+、Mg2+、SO42-和PO43-对精矿Si O2、Fe2O3和Al2O3品位影响较小。为了降低有害离子对浮选指标的影响,1#磷矿样浮选回水中Ca2+、Mg2+和SO42-浓度应分别控制在1610 mg/L、550 mg/L和5500 mg/L以内。2#磷矿样浮选回水中Ca2+、Mg2+和SO42-浓度应分别控制在1640 mg/L、600 mg/L和4800 mg/L以内。浮选溶液化学计算表明:在矿浆p H为3~4时,难免离子主要以Ca2+、Mg2+和H2PO4-的形式存在。捕收剂GJBW主要以可溶的RCOOH分子形式存在,在白云石表面产生分子吸附。Ca2+和Mg2+能沉淀解离的RCOO-,降低捕收剂的有效浓度,且Ca2+对捕收剂的沉淀作用强于Mg2+,导致Ca2+对精矿P2O5品位影响大于Mg2+。SO42-能与Ca2+相互作用生成硫酸钙沉淀,XRD分析和SEM分析均表明硫酸钙能沉淀在氟磷灰石表面。硫酸钙的吸附会增强氟磷灰石的可浮性,导致氟磷灰石随白云石一起浮出,进而降低精矿P2O5回收率。此外,SO42-的加入会增加GJBW溶液的表面张力,进而影响浮选指标。
[Abstract]:Fluoroapatite is a kind of micro-soluble salt mineral, its flotation is easy to be affected not only by self-dissolved lattice ions, but also by other salt mineral dissolved components in the same flotation system. Moreover, because of the poor selectivity of fatty acid collectors, they are sensitive to dissolved ions in flotation. Therefore, it is of great significance to systematically study the influence of complex ions on flotation of phosphate ore, and to carry out targeted wastewater treatment and clean utilization of backwater in the concentrator. In this paper, two representative phosphate rock samples in Guizhou area are taken as the research object, the suitable flotation process is determined by flotation condition test, and the influence of complex ions on the reverse flotation index of phosphate rock is investigated by single factor test and orthogonal test. The minimum concentration of harmful ions affecting flotation index was determined, and the mechanism of complex ions affecting the index of reverse flotation was studied by XRD analysis and surface tension measurement. The useful minerals in the two phosphate samples selected in the experiment are fluorophosphatite, the gangue minerals are mainly dolomite and the grade of P _ 2O _ 5, mg _ O and Sio _ 2 in the sample containing a small amount of quartz 1# is 28.72% and 5.78%, respectively, and the grade of P _ 2O _ 5, mg _ O and Sio _ 2 in the phosphate rock sample is 22.677.58% and 4.30%, respectively. For the sample of Phosphate, the suitable grinding fineness of -75 渭 m was 80.67% and the dosage of H _ 2SO _ 4 and collector were 14 kg/t and 0.6 kg / t, respectively. Under these conditions, the grade and recovery of P _ 2O _ 5 are 35.82% and 95.43% respectively. For phosphorus ore sample of 2#, the suitable grinding fineness is -75 渭 m (-75 渭 m) and the amount of H _ 2SO _ 4 and collector is 18 kg/t and 0.8 kg / t, respectively. Under these conditions, the flotation index obtained is as follows: the grade of P _ 2O _ 5 is 33.81% and the recovery rate of P _ 2O _ 5 is 87.16%, and the MgO _ (1.20) and Sio _ 2 _ (5) O _ (2) 5. 48% Al _ 2O _ 3 0.63 and Fe _ 2O _ 3 1.10 can be added. After the concentrate filtrate is returned to flotation, the concentration of Ca 2 + mg 2 so 4 2-N TP and F-in the return water increases gradually with the increase of the times of circulation of the filtrate, and the ion "accumulation effect" exists, and the recovery rate of P 2O 5 is affected by the reuse of water. In the system of single ion, Ca 2 and mg 2 can decrease the grade of P _ 2O _ 5 and increase the mg _ O grade of concentrate. So _ 42- has a great influence on the index of reverse flotation of phosphate ore. In particular, the effects of P _ 2O _ 5 recovery, Ca ~ (2 +) and so _ (4) _ (2-) on flotation of phosphorus ore samples are greater than those of 1# phosphate samples. The effect of Ca ~ (2 +) mg _ (2) so _ (4-) and PO _ (43)-on the flotation index is smaller than that on the grade of Fe _ 2O _ 3 and Al _ 2O _ 3 in concentrate Sio _ 2O _ 2O _ 2O _ 3 and Al _ 2O _ 3. In order to reduce the effect of harmful ions on flotation index, the concentration of Ca2 + Mg2 and SO42- in flotation water of phosphate rock samples should be controlled within 1610 mg / L 550mg / L and 5500 mg / L respectively. The concentration of Ca2 + Mg2 and SO42- should be controlled within 1640 mg / L 600 mg / L and 4800 mg / L respectively. The chemical calculation of flotation solution shows that when pH is 3 ~ 4, the inevitable ions mainly exist in the form of Ca2 + Mg2 and H2PO4-. The collector GJBW mainly exists in the form of soluble RCOOH molecule. The adsorbed. Ca 2 and mg 2 can precipitate dissociate RCOO-on the surface of dolomite, which can reduce the effective concentration of collector, and the precipitation effect of Ca 2 on the collector is stronger than that of mg 2. As a result, the effect of Ca 2 on the grade of P _ 2O _ 5 is greater than that of mg _ 2 路so _ 42- and Ca ~ (2 +) to form calcium sulfate precipitate. XRD analysis and SEM analysis show that calcium sulfate can precipitate on the surface of fluoroapatite. The adsorption of calcium sulfate will enhance the floatability of fluoroapatite and lead to the floatation of fluoroapatite with dolomite, thus reducing the recovery rate of P _ 2O _ 5 in concentrate. In addition, the addition of so _ 4 _ 2- can increase the surface tension of GJBW solution, and then affect the flotation index.
【学位授予单位】：贵州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD97

【参考文献】