Progress in theory and basic research of phosphate ore dressing

Wang Shulin et al. conducted a study on the process mineralogy of Yichang Phosphate Mine in order to explore the occurrence of major components in Yichang Phosphate Mine and the process properties of mineral strips to determine the feasibility of its heavy medium beneficiation process. Firstly, chemical composition analysis and fluorescence component analysis were used to determine the mineral composition and chemical composition of each band in the ore. The dissociation of each band in the ore was measured, and the density distribution of each band was carried out by the heavy liquid floatation method. test. The results show that 98.98% of P2O5 in Yichang phosphate ore is distributed in the phosphorite belt, while the phosphorite band contains 2.29% sesquioxide and the mass fraction of phosphorite is 81.32%. The belt and gangue strips have a large width and a hardness difference between the strips. The phosphorite strips are easily dissociated by the monomers; the sorting density is 2.7-2.9 g/cm3, and the phosphorite strips and clay strips Can be sorted by heavy medium beneficiation. Therefore, Yichang Phosphate Mine uses heavy medium mineral processing. The phosphorus rock band in the ore can be selected first, and then the sesquioxide is treated to obtain the desired high quality phosphate concentrate.

In order to study the fragmentation law of phosphate ore under static load, Qiu Yueqin used the rock fracture process analysis system RFPA2D to establish a numerical model for the failure of multi-particle phosphate ore in the crushing cavity under static load, and analyzed the static load. And the effect of the restraining action of the crushing cavity on the crushing effect and energy consumption of the phosphate ore multi-particle sample. The numerical simulation results show that when the static load breaks the multi-particle phosphate ore, the number of destruction units of the phosphate ore particles in the middle of the crushing cavity is relatively large; the energy consumed by the crushing unit in the crushing cavity within a certain range of compression deformation Relatively small. Therefore, in order to obtain better crushing efficiency and energy saving effect, the particle breaking behavior should be considered when designing the crusher .

He Ting Application of rock failure process analysis model for numerical RFPA2D thirty ZHIJIN expensive rare earth-containing phosphate rock particles, discusses the analysis of different constraints on the crushing effect and the rare earth-containing phosphate rock energy consumption of the sample particles under the static load of influences. The numerical simulation results show that the number of cumulative failure units of rare earth phosphate ore particles in the horizontal direction is less than that without horizontal constraint, and the energy released is more than that without horizontal constraint. Therefore, in order to obtain better crushing efficiency and energy saving effect, the constraint state of the rare earth-containing phosphate ore particles in the crushing chamber should be considered when selecting the crusher.

Baizhong can find the enrichment of the low-grade colloidal ore concentrate flotation concentrate grade, and there is a necessary relationship and specific quantitative relationship with the removal of magnesium , silicon and other impurities. It is proposed that the flotation concentrate grade of low-grade colloidal phosphate ore and magnesium, silicon and other impurities have the following quantitative relationship: β = α + 1.3 × k1 + 0.42 × k2 + 1.5%. Where: β——predicted grade of concentrate grade, %; α—analytical grade of raw ore grade, %; k1—the absolute value of MgO removal, %; k2—the absolute value of SiO2 removal, %. The application of this relationship has a strong guiding role in the selection of the flotation process of siliceous calcium phosphate rock and the preliminary judgment of the quality of the concentrate.

Yao Weidong and others used ultrasonic to pretreat a phosphate rock, and studied the effect of ultrasonic action time and action power on the surface potential of the particles; the effect of ultrasonic on the particle size of the mineral particles; the two methods of cleaning the elution mud and flotation Enhance the contrast of effects. The results show that (1) the effect of ultrasonic on the surface potential of phosphate rock particles is obvious. The ultrasonic wave can increase the surface potential of the particles under the experimental pH value, while the ultrasonic wave has no obvious effect on the crushing of fine particle size mineral particles. (2) The mineral activity increases after ultrasonic treatment, and the recovery rate can be significantly improved for the rubbing sludge; for the flotation, the concentrate grade can be improved under the same pharmaceutical system conditions.

Wei Yihe et al. illustrate the evolution of the positive and negative flotation process and the changes in the flotation characteristics of various minerals, and then analyze the possible problems of positive and negative flotation in Yunnan phosphate mine, and point out The direction of improvement. According to the analysis, due to the large difference in hardness of various mineral components in phosphate rock, the fine grinding results in extremely uneven particle size of the grinding products, so that a large number of fine particles and fragile minerals such as dolomite are selectively enriched in the fine fraction. . Since dolomite and phosphorus minerals are similar in buoyancy under alkaline positive flotation conditions, a large number of fine-grained dolomites in the ore flotation are inevitably competing with phosphorus minerals to adsorb flotation reagents. The coarse-grained grade of the positive flotation phosphorus mineral is more difficult to float, while the fine-grained grade is seriously mixed, and the flotation agent, especially the collector, tends to consume more. This effect of particle size will continue into the reverse flotation stage and result in a decrease in reverse flotation efficiency. To solve the interaction between the coarse and fine particles of the flotation, the following methods can be used: (1) The coarse fraction is difficult to float, and high-concentration pulping can be performed to reduce the amount of flotation reagent; (2) fine particles The grade is relatively easy to float, but the general inclusion is more serious, and the selection is more difficult. Therefore, the flotation of this part needs to strengthen the dispersion process, and some strong dispersing agents can be added to the flotation; (3) Fine flotation equipment can be used more Concentrated and energy efficient flotation column flotation. In short, the coarse and fine strengthening treatment can avoid the mutual interference between coarse and fine particles during mixed flotation, improve the sorting efficiency and flotation concentrate quality, reduce the flotation agent consumption, and improve the technical and economic indicators of the whole positive and negative flotation. .

Liu Shaowen systematically studied Hubei Baokang calcareous phosphate rock and Dagukou siliceous calcium phosphate rock by grading flotation, chemical comparison and combined flotation of phosphate rock particles. The results show that the small-grained phosphate rock with a particle size of -65 μm after classification is more favorable for reverse flotation, and the anti-flotation effect of Baokang phosphate mine is better than that of Dagukou phosphate rock; both composite agents and acid inhibitors can improve the protection. The flotation effect of the calcareous phosphate rock, the final phosphorus concentrate grade reached 36.14%, the phosphorus recovery rate was 96.10%; the reduction of the surface tension of the agent can enhance the wetting of the phosphate rock particles. Finally, the efficiency of the flotation process was analyzed by measuring the zeta potential and the hydrophilic-lipophilic balance, and the flotation mechanism was discussed.

Wei Yihe et al. pointed out the problems existing in the positive and negative flotation continuity experiment (returning water flow) of a phosphate rock through the particle size analysis of flotation products, and proposed improvement suggestions. The particle size analysis showed that the use of backwater after treatment had no adverse effect on the positive and negative flotation. The use of backwater enhanced the suppression of fine-grained siliceous minerals in the positive flotation, and also improved the flotation of phosphorus and magnesium minerals; The positive and negative flotation process of the return water is similar to the fresh water flow in each particle level, and the problems are the same. How to improve the suppression effect of fine-grained siliceous minerals in the positive flotation and the flotation yield of fine-grained phosphorus minerals is the key to improve the quality and yield of the phosphate ore flotation concentrate and reduce the consumption of the medicament.

Starting from Kan Ping Yu et COLLECTING relationship with the structure of conventional flotation collector, collector analysis polar group in the molecule, non-polar structures affect iron ore and collophanite collecting capability proposed anti-iron The design concept of the flotation phosphorus-reducing collector molecule is considered to be that the polar group in the new collector molecule should contain a sulfonic acid group, and the non-polar group should have an unsaturated bond. The net charge distribution, dipole moment and frontier orbital energy and composition of the designed molecules were calculated by Gaussian software, and compared with common collectors, the designed collector molecules were able to capture the collite. From the mechanism analysis, it is concluded that under the specific pH condition, the reverse flotation collector molecules chelate with Ca2+ on the surface of the phosphate rock to form a stable six-membered ring, thereby achieving separation from iron ore.

Li Feng et al. designed and synthesized a carbonate collector α-hydroxyoleic acid with soy oleic acid as a raw material, and carried out a flotation test of colloidal phosphate and dolomite pure minerals. The results showed that α-hydroxyoleic acid was A carbonate collector excellent in flotation performance. Through scanning electron microscopy and solution chemistry test, Li Feng et al further studied the mechanism of action of α-hydroxyoleic acid. The results of scanning electron microscopy showed that α-hydroxyoleic acid floated on dolomite and collophanite under the same acidic conditions. The difference is better than soy oleic acid. The results of surface tension test showed that the critical micelle concentrations of α-hydroxyoleic acid and soybean oleic acid were 5.37 x10-3 mol/L and 1.06 x10-3 mol/L, respectively, and the minimum surface tension was 26.99 mN. /m and 28.6 5 mN/m. The results show that the chemical modification of soybean oleic acid improves the water solubility and dispersibility, thereby improving its utilization efficiency and improving its ability to reduce surface tension, thus enhancing its foaming ability and improving its ability. Its flotation. The results of wet contact angle test show that the wetting ability of α-hydroxyoleic acid to pure minerals of collophanite and dolomite is less than that of soybean oleic acid, but from the difference of contact angle, α-hydroxyoleic acid is superior. For soybean oleic acid, the maximum difference in contact angle between the two collectors was 21.45o and 17.86o, respectively. It is indicated that the addition of a pro-mineral group to α-hydroxyoleic acid and soybean oleic acid is beneficial to enhance the electrostatic adsorption force on dolomite (gangue composition) and improve the selectivity of flotation dolomite.

Liu Xin used industrial sterol Zc and etheramine collector Y10 as a floating silicon collector to carry out a double reverse flotation process test. The ore grade was P205 26.22%, MgO 1.60%, SiO2 22.33. When % is obtained, a concentrate index of P20530.14%, MgO 0.61%, and recovery rate of 92.99% can be obtained. Surface tension and relative contact angle tests found that the addition of industrial fuselage Zc improved the selectivity of Y10.

YY1 is a carbonate mineral inhibitor. After adding YY1 to the flotation of phosphate rock, the mass fraction of MgO in Zhengfu tailings increased from 2.31% to 18.23%, and the recovery rate of MgO in tailings increased from 8.86% to 46.88%. The recovery rate of MgO in concentrates decreased from 91.12% to 53.11%, indicating that YY1 has obvious inhibitory effect on carbonates such as dolomite. Liang Yongzhong et al. discussed the mechanism of action of YY1: because the solubility of carbonate minerals is greater than that of phosphate rock, it dissolves on the surface of carbonate minerals in water and exposes Ca2+ and Mg2+ active centers, so that YY1 is adsorbed in carbonates in large quantities. On the mineral, the hydroxyl group and the alcohol group on YY1 are hydrophilic polar groups, which can increase the wettability of the mineral and inhibit the hydrophilicity of the mineral. However, due to the low solubility of the phosphate rock, the surface adsorbed YY1 is less than the carbonate mineral, the original floatability is suppressed, and it can still exhibit a certain floatability. Therefore, YY1 is a selective inhibitor of carbonate. Mineral inhibitors.

Wang Yonglong et al. investigated the floatability of fine-grained colloidal phosphate in sodium oleate system by single mineral flotation test, and compared the five inhibitions of sodium hexametaphosphate, sodium silicate, sodium pyrophosphate, starch and sodium humate. The inhibitory effect of the agent on the fine colloidal phosphate rock. The test results show that the suitable conditions for sodium oleate flotation of fine-grained phosphate rock should be slurry temperature 45 °C, pH adjustment of pulp with NaOH=10, sodium oleate 6×10-4 mol/L; The order of inhibition of micro-grain phosphate rock is sodium humate > sodium hexametaphosphate > starch > sodium pyrophosphate > sodium silicate.

Deng Rongdong et al. carried out flotation experiments on low-grade siliceous phosphate rock in Yunnan, using normal temperature positive and negative flotation process, and using Box-BenhnkenDesign in design-expert 8.0 software for rough flotation and reverse flotation operations. The design test scheme is optimized to obtain the best solution for rough flotation rough selection: pH 10, 731 dosage 1.1 kg/t, water glass dosage 5.3 kg/t. The optimized reverse flotation conditions are the volume ratio of sulfuric acid to phosphoric acid 2..1, the pH value of the slurry is 4.1, the amount of HC is 0.01 kg/t, and the inhibition time is 1.5 min. The final test index is 29.35% phosphorus concentrate grade, 83.14% recovery rate and 0.83% MgO mass fraction. The index is good.

Xiaoqu's research on flotation experiments of a phosphate rock mine in Hunan shows that the single reverse flotation process can't make the P2O5 grade reach more than 28%, which can't meet the lowest index of available apatite. Through the positive and negative flotation process, when the grinding is fine When the degree is -0.074mm and the mass fraction is 97.38%, the closed process with "one coarse and two fine", positive floating coarse selection and reverse floating selection can obtain a yield of 36.46%, a grade of 30.27%, and a recovery rate of 66.02%. The final concentrate with a MgO mass fraction of 1.05% meets the secondary industrial index of acid-based phosphoric acid. The study on the mechanism of action of flotation reagents and minerals shows that under weak acid conditions, the surface electrical properties of apatite and dolomite are quite different, which is favorable for flotation separation, and the adsorption of YSB-2 on dolomite surface is stronger than that of phosphorus. Gray stone; water glass in alkaline medium, mainly in the form of HSiO3-, HSiO3- has the same acid root as silicate mineral, easy to adsorb on the surface of these minerals, and the adsorption is relatively firm, on quartz , silicate and other veins Stone minerals have a good inhibitory effect.

In the test process, Chen Hui selected AMS+MS-1 as a surfactant blended with cotton soap soap by the rough selection test of colloidal phosphate, and the two surfactants were low with cotton soap. The compounding ratio is compounded into a normal temperature collector for the exploration of the flotation process conditions of the low-grade colloidal phosphate rock in Dagukou. The test results show that the collector can float the phosphate rock under normal temperature conditions and achieve better flotation index. Through the study of the interaction mechanism between collectors and minerals, the surface tension and foaming properties of flotation reagents and the relative contact angles before and after the action of chemicals and minerals, mineral surface electrical properties and infrared spectroscopy experiments show that the pH value is 10 ~11 hours, this compound collector adsorbs fatty acid collector on the mineral surface after a certain amount of action with minerals, and increases the gangue minerals such as silicate minerals and carbonate minerals of phosphate rock and its symbiotic The difference in flotation performance is beneficial to the flotation of the phosphate rock.

Because when the slurry contains a lot of mud, the cationic reverse flotation will have more foam, the foam is sticky, and the flotation effect is worse, which leads to the industrial application of the cationic collector. Zeng Xiaobo regulates the behavior of flotation three-phase interface by adding antifoaming agent to flotation slurry to solve the problems in the use of current cationic collector. Three antifoaming agents were selected: organic defoamer fatty alcohol, mineral flocculant PA and inorganic foam regulator CA. The test results show that the inorganic foam regulator CA has the best defoaming effect, and it is easy to use and has a wide range of sources. cheap price. The mechanism study shows that after adding defoamer CA, γLG decreases, WSL decreases, that is, the solid-liquid interface binding force decreases, and the minimum work required to pull the solid-liquid contact from the junction is also reduced, thereby reducing the minimum work. The concentration of the collector on the foam film makes the foam thinner and brittle, and the defoaming is easier. The Zeta potential test shows that the negative value of the zeta potential of the quartz surface decreases after the addition of CA, the zero point of the zero point shifts slightly, and the potential of the quartz potential rises. Highly compressed double layer; infrared spectroscopy showed that the addition of defoamer did not affect the performance of the collector, and did not affect the flotation index.

Wei Yihe et al. investigated the effect of common phosphate rock flotation agents on the clarification properties of flotation tailings using a simple method. The results show that the test method has small error and can be used to evaluate the effect of flotation reagent on the clarification performance of flotation tailings. Among the flotation chemicals in Haikou Phosphate Mine, the regulator water glass has the greatest influence on the clarification performance of flotation tailings, followed by MW. The amount of collector has little effect on the clarification performance of flotation tailings, but the type of collector has a great influence on the clarification performance of flotation tailings. The tailings clarification performance of the industrial collector H969 flotation is much lower than that of the tailings when industrial oleic acid is used. The use of synergists improves the clarification properties of the flotation tailings.

The evaluation of the flotation collector helps to understand the flotation performance of the collector and understand its role in the flotation process. The flotation method is a traditional evaluation method for flotation collectors, which is complicated, time-consuming and labor-intensive. Li Fang et al. proposed a new flotation research method: combustion-adsorption quantity evaluation method, which measures the organic absorption dose adsorbed on the surface by burning inorganic ore samples to evaluate the performance of phosphate rock reverse flotation collector. The evaluation model of the combustion-adsorption amount evaluation method was established for the flotation performance of oleic acid, stearic acid and palmitic acid, and the flotation performance of fatty acids familiar to flotation workers and adsorption on dolomite. .

Jin Huixin et al. studied the flotation kinetics of Zhijin Xinhua Rare Earth-containing phosphate rock. Based on the typical first-order flotation dynamics model ε=ε∞(1-e-kt), the phosphate rock reversed. Flotation rate model ε=ε∞+(100-ε∞)ek(t+θ), and according to the kinetic orthogonal experiment, using three-dimensional surface map and contour map to calculate the kinetic parameters of Zhijin Xinhua Phosphorite flotation Characterized. The results show that the reverse flotation rate model can well describe the rule of recovery of rare earth-containing phosphorus minerals (represented by ΣREO) and gangue minerals (expressed by MgO) with time, and with the modified flotation rate constant kmod and The selectivity index SI is used to measure the effect of sorting the rare earth-containing phosphorus minerals and gangue minerals. Through flotation orthogonal kinetics experiments, the amount of collector WF-01 is the most important factor affecting the ΣREO correction rate constant kmod, and the inhibitor H3PO4 dosage is the most important factor affecting the selectivity index SI. The three-dimensional surface map and contour plots were used to characterize the changes of flotation kinetic parameters of ΣREO in the combination of two reagents. The reverse flotation of phosphate rock, such as collector WF-01, was 0.8 kg/t. In order to obtain a better sorting effect of rare earth-containing phosphorus minerals and dolomite minerals, the amount of inhibitor H3PO4 can be appropriately increased.

Zhang Min et al. based on sieve plate filling, optimized the filling method of the cyclone-static microbubble flotation column flotation section, and proposed an efficient mixed filling mode of sieve plate filling and honeycomb tube filling; based on bubble-mine The particle collision probability theory is used to analyze the superiority of honeycomb tube filling, and the dynamic model of collision probability between bubbles and ore particles is derived. The axial diffusion model is used to analyze the role of mixed filling in ensuring recovery rate, and the capture area is derived. The axial dimensionless diffusion model; the mixed filling keeps the lower part of the flotation column in a highly turbulent state while the upper flotation section forms a "static" environment.

Qing Li introduced the main structure and working principle of CPT flotation column and FCSMC flotation column respectively. Combined with the characteristics of column flotation test sorting system, the paper analyzed the influence of column flotation process parameters on sorting index, and floated according to FCSMC. The semi-industrial test data of column selection, using the regression analysis method, established the mathematical model of the flotation of the phosphate rock column, summed up the recovery index of the column flotation depends on three factors: column flotation rate constant K value, floated mineral The average residence time Ï„P in the flotation column and the mixed state of the slurry in the flotation column. It laid a theoretical foundation for the flotation test design of low-grade colloidal phosphate rock column in Yunnan Province.

Based on the grade distribution, Wang Dapeng analyzed the operation characteristics of each sorting area in the columnar flotation process of the collo-phosphorus ore. Based on the theoretical model of the pre-human column flotation dynamics, the colloidal phosphate mine was derived by using the tandem model. Column axial grade distribution model. Under the guidance of studying the floatability characteristics of the flotation process, the particle size flotation characteristics of the phosphate rock flotation process were further studied. By studying the variation law of flotation speed of each grain fraction, the process characteristics of “thin” and “coarse” before the flotation of granular phosphate rock were revealed. Based on this, based on the analysis of the characteristics of the coarse and fine-grained mineralization process, a granular “step-by-step” flotation process for the phosphate rock is proposed: according to the time distribution characteristics of the flotation process in the flotation process, to strengthen and adjust In order to achieve stepwise strengthening and flotation of the colloidal phosphate grade by changing the turbulent intensity, bubble characteristics, foam layer height and other targeted operating parameters, coarse and fine particles are established under the framework of high efficiency column sorting process. The highly efficient sub-process with targeted enhancement has achieved efficient flotation of the full-grain grade of the phosphate rock. So far, the high-efficiency flotation equipment system and process model of the colloidal phosphate mine have been formed: an integral column efficient process based on the characteristics of the floatable process and a sub-process based on the particle size flotation feature.

Wu Yuanxin and Zhang Wenxue proposed a technological route to develop colloidal phosphate resources using systematic engineering principles for the characteristics of low-grade phosphate rock in Yunnan. Based on the research of digital mine technology, the optimal ore grade is determined. The best mineral processing technology and high-efficiency flotation reagent system are formulated through detailed analysis of the process mineralogical characteristics of phosphate rock. At the same time, the simple wastewater treatment process is used to realize the zero of ore dressing wastewater. Emissions not only developed the low-grade phosphate rock around the Dianchi Lake in Yunnan, but also avoided environmental pollution, effectively protecting the Dianchi Lake water body.

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