Beneficiation method for removing iron and aluminum sesquioxide from high-grade collophanite

Abstract

The invention relates to a beneficiation method for removing iron and aluminum sesquioxide from high-grade collophanite, and belongs to the technical field of mineral processing. The method comprises the following steps: performing crushing, superfine and grading on raw ore to obtain materials, and feeding the materials into gravity separation operation to obtain gravity separation concentrate and gravity separation tailings; the gravity concentrate is fed into a reverse flotation magnesium removal operation buffer tank, gravity tailings are thickened, after regrinding and grading, direct flotation desliming and direct flotation desilicication are conducted, and the obtained concentrate is subjected to reverse flotation magnesium removal operation; three water return pools are built for storing direct flotation desilicication return water, reverse flotation magnesium removal return water and reselection operation return water respectively. The method mainly aims at high-grade high-power semi-silicon-calcium collophanite, gravity-flotation combined separation quality-divided branch flotation is adopted, raw ore is divided into gravity concentrate and gravity tailings through gravity separation equipment, the gravity tailings are subjected to direct and reverse flotation to obtain gravity tailings flotation concentrate, the separation process fully utilizes the respective advantages of direct and reverse flotation and gravity separation, the technological process is stable, and the separation efficiency is high. And the separation effect is good, and high-quality and low-quality use of the phosphate concentrate is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of mineral processing, and in particular relates to a beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite. Background Art

[0002] In my country, phosphate resources are mainly concentrated in Yunnan, Guizhou, Sichuan, Hunan, Hubei and other places, mainly sedimentary phosphorite, among which medium and low-grade collophanite is the main one. Some high-grade siliceous collophanites contain high levels of aluminum and iron sesquioxides (R2O3). In the traditional wet production of phosphoric acid, there are clear requirements for iron and aluminum sesquioxides: the sesquioxide content of Class I phosphate concentrate shall not exceed 2.5%; the sesquioxide content of Class II phosphate concentrate shall not exceed 3.0%. The content of iron and aluminum oxides in phosphate ore is often expressed as R2O3 (R represents Fe and Al, that is, Fe2O3+Al2O3). Iron and aluminum not only interfere with the growth of calcium sulfate crystals, but also cause phosphoric acid to form sludge. Phosphate ore reacts with acid to generate water-insoluble complex phosphates, which will cause a large loss of P2O5 when precipitated or removed with gypsum. The resulting complex phosphates of iron and aluminum have fine crystals, which not only increase the viscosity of the solution and slurry, but also easily clog the pores of the filter cloth and filter cake. The phosphates of iron and aluminum will also bring difficulties to post-processing such as the concentration and drying of phosphoric acid or ammonium phosphate slurry, and lead to poor product properties and quality degradation. Therefore, in order to reduce the impact on the wet phosphoric acid and acid fertilizer production process, it is necessary to reduce the content of iron and aluminum sesquioxides in the phosphate concentrate as much as possible.

[0003] At present, for high-aluminum, high-iron, low-grade calcareous silicate phosphate, the conventional process flow is the direct-reverse flotation process flow and the pre-de-sludge-double reverse flotation process flow. The direct-reverse flotation process has the disadvantages of fine grinding fineness, fine concentrate product particle size, difficult concentrate transportation and dehydration operations, and high concentrate beneficiation costs. In addition, the direct-reverse flotation process must rely on tailings ponds to operate normally, and it is difficult for new phosphate mines to approve tailings ponds. The pre-de-sludge-double reverse flotation process has the disadvantages of poor reagent selectivity, the process is greatly affected by ore slime, severe P2O5 loss in de-sludge operations, and a low final concentrate P2O5 recovery rate. Summary of the invention

[0004] The technical problem to be solved by the present invention is to propose a new beneficiation method for removing iron and aluminum sesquioxide from high-grade collophanite in view of the shortcomings of the prior art. The process is more reasonable and efficient in removing carbonate, iron-containing and aluminum-containing gangue minerals from collophanite.

[0005] The technical problem to be solved by the present invention is achieved by the following technical solution. The present invention is a beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite, which is characterized in that the steps are as follows: (1) The medium-high aluminum siliceous colloidal phosphate ore is crushed, then ultra-finely crushed and screened to -3mm before being fed into the powder ore bin; (2) The materials at the bottom of the powder ore bin are fed into the grinding and classification process by a disc feeder and then into the gravity separation buffer tank; (3) The slurry in the gravity separation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings; (4) The gravity separation concentrate is fed into the reverse flotation de-magnesium buffer tank, the gravity separation tailings are fed into the thickener operation, the thickener underflow is fed into the tailings regrinding and classification operation, and the ground slurry is fed into the direct flotation de-siliconization buffer tank; (5) The positive flotation desiliconization buffer tank is first fed into the positive flotation desliming operation, and the deslimed ore pulp is then fed into the positive flotation desiliconization operation. The concentrate from the positive flotation desiliconization is fed into the reverse flotation demagnesization operation. The tailings from the positive flotation and the desliming flotation tailings are fed into the positive flotation tailings dewatering operation. The concentrate from the reverse flotation is fed into the reverse flotation concentrate dewatering operation, and the tailings from the reverse flotation is fed into the reverse flotation tailings dewatering operation. Three return water tanks are built to store the return water from the positive flotation desiliconization, the return water from the gravity separation, and the return water from the reverse flotation demagnesization. The medium-high aluminum siliceous collophosphate ore group has a P2O5 grade of 27.5%~29.8%, a MgO mass content of 1.1%~2.5%, a SiO2 mass content of 11.5%~14.5%, an Al2O3 mass content of 1.5%~3.0%, and a Fe2O3 mass content of 1.2%~2.5%.

[0006] The beneficiation method for removing iron and aluminum sesquioxide from high-grade collophanite described in the present invention is further optimized as follows: in the ultra-fine crushing and screening, a high-pressure roller mill is used for ultra-fine crushing, and a relaxation screen is used for screening.

[0007] The present invention discloses a beneficiation method for removing iron from aluminum sesquioxide from high-grade collophanite, wherein a further preferred method is as follows: the grinding and classification operation adopts a rod mill or a grate ball mill for grinding, the grinding and classification adopts two-stage classification, the first stage adopts a micro powder screen or a fine screen, the sieve hole particle size is controlled at 0.1-0.15 mm, the second stage adopts a cyclone classification, the classification particle size is controlled at 74 μm, and the grinding fineness of the material before flotation is controlled at 55%-65%.

[0008] The present invention discloses a beneficiation method for removing iron from aluminum sesquioxide from high-grade collophanite, wherein a further preferred method is as follows: the gravity separation operation adopts two-stage classification plus one-stage gravity separation, the two-stage classification adopts a cyclone + a micro powder screen, the cyclone is controlled at 10-38 μm, the micro powder screen is controlled at 0.5-1 mm, the gravity separation adopts one or a combination of two of an interference bed, a shaking table, a spiral chute, a belt chute and a centrifugal concentrator, and the gravity separation operation includes roughing, cleaning or scavenging.

[0009] The present invention discloses a beneficiation method for removing aluminum sesquioxide from high-grade collophanite, wherein a further preferred method is as follows: the reverse flotation magnesium removal process mainly removes carbonate-containing minerals, the inhibitor is selected from sulfuric acid, phosphoric acid, phosphate or a combination of the above agents, the collector is selected from a combination of fatty acid soap and xanthate, and the reverse flotation operation includes roughing and scavenging.

[0010] The present invention discloses a beneficiation method for removing aluminum sesquioxide from high-grade collophanite, wherein a further preferred method is: adding a flotation desliming operation before a positive flotation desiliconization operation, and using polyacrylamide and 2# medicine as collectors.

[0011] The present invention discloses a beneficiation method for removing aluminum sesquioxide from high-grade collophanite, wherein a further preferred method is as follows: the positive flotation operation mainly removes mud silicate gangue minerals, the flotation environment is alkaline, the alkaline adjuster uses sodium carbonate as a pH adjuster, water glass is used as an inhibitor, and the collector uses unsaturated fatty acid organic matter, and the positive flotation operation includes roughing and cleaning operations.

[0012] The present invention discloses a beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite, wherein a further preferred method is: re-grinding and classifying the re-selected tailings, using a tower mill for grinding to further separate useful minerals from gangue minerals, and the grinding fineness is -200 mesh 85% to 95%.

[0013] The present invention discloses a beneficiation method for removing aluminum sesquioxide from high-grade collophanite, wherein the return water from the gravity separation return water tank is used for a first-stage grinding operation and a gravity separation operation, a part of the return water from the reverse flotation demagnesium return water tank is used for the reverse flotation demagnesium operation, and the other part is used for the direct flotation desiliconization operation after being treated to be qualified, the return water from the direct flotation desiliconization return water tank can only be used for the direct flotation operation and the gravity separation tailings regrinding operation, and the return water from the reverse flotation operation can only be used for the direct flotation desiliconization process after being treated by a double alkali process.

[0014] The most preferred technical solution of the ore dressing method for removing iron-aluminum sesquioxide from high-grade collophanite described in the present invention is: (1) The raw ore is crushed by conventional crushing. Conventional crushing is based on the feed size. If the feed size is above 500mm, three-stage crushing is adopted. If the feed size is below 500mm, two-stage crushing is adopted. The particle size after crushing is controlled above -30mm. The first stage of conventional crushing adopts jaw crusher, followed by cone crusher. The finely crushed ore is then fed into the ultra-fine crushing and screening system composed of high-pressure roller and vibrating screen for further ultra-fine crushing. The ultra-fine crushing and screening operation adopts relaxation screen, and the screening particle size is designed to be 3mm. The qualified materials under the screen are fed into the powder ore bin, and the materials on the screen are returned to the high-pressure roller mill; (2) The materials at the bottom of the powder ore bin are quantitatively fed to the grinding and grading operation by a disc feeder. The disc feeder adopts frequency conversion speed regulation. The grinding operation adopts a rod mill or a grate ball mill. The grading operation adopts two-stage grading. The first stage adopts a micro powder screen or a fine screen, and the sieve hole particle size is controlled at 0.1~0.15mm. The second stage adopts a cyclone classification, and the classification particle size is controlled at 74μm. The grinding fineness of the material before gravity separation is controlled at 55%~65%. The qualified particle size of the grading operation is fed into the gravity separation buffer tank; (3) The slurry in the gravity separation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings. The gravity separation operation adopts two-stage classification plus one-stage gravity separation. The two-stage classification adopts a cyclone + a micro powder screen. The cyclone is controlled at 10~38μm and the micro powder screen is controlled at 0.5~1mm. The gravity separation uses one or a combination of interference bed, shaking table, spiral chute, belt chute and centrifugal concentrator. The gravity separation operation includes roughing, cleaning or scavenging; (4) The gravity separation concentrate is fed into the reverse flotation de-magnesium buffer tank, the gravity separation tailings are fed into the thickener, the thickener bottom flow is fed into the tailings regrinding and classification operation, the ground slurry is fed into the direct flotation de-siliconization buffer tank, the gravity separation tailings are regrinded and classified, and the tower mill is used for grinding to further separate the useful minerals and gangue minerals. The grinding fineness is -200 mesh 85%~95%. The reverse flotation depressant is selected from sulfuric acid, phosphoric acid, phosphate or a combination of the above agents, and the collector is a combination of fatty acid soap and xanthate. The reverse flotation operation includes roughing and scavenging; (5) The direct flotation desiliconization buffer tank is first fed into the direct flotation desliming operation, and the deslimed ore pulp is then fed into the direct flotation desiliconization operation. The concentrate from the direct flotation desiliconization is fed into the reverse flotation demagnesization operation. The tailings from the direct flotation and the deslimed flotation tailings are fed into the direct flotation tailings dehydration operation. The concentrate from the reverse flotation is fed into the reverse flotation concentrate dehydration operation. The tailings from the reverse flotation is fed into the reverse flotation tailings dehydration operation. The flotation desliming operation is added before the direct flotation desiliconization operation. The collectors are polyacrylamide and 2# medicine. The direct flotation operation mainly removes muddy silicate gangue minerals. The flotation environment can be alkaline. The alkaline adjuster is sodium carbonate as the pH adjuster, and water glass is used as the inhibitor. The collector is unsaturated fatty acid organic matter. The direct flotation operation includes roughing and concentrating operations.

[0015] (6) The whole plant has three return water tanks, which store the return water from direct flotation desiliconization, gravity separation and reverse flotation demagnesiumization respectively. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used for the direct flotation desiliconization process. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used for the direct flotation desiliconization process.

[0016] The original ore composition of medium-high aluminum siliceous collophanite is P2O5 grade of 27.5%~29.8%, MgO mass content of 1.1%~2.5%, SiO2 mass content of 11.5%~14.5%, Al2O3 mass content of 1.5%~3.0%, and Fe2O3 mass content of 1.2%~2.5%; the P2O5 grade of the collophanite concentrate obtained by the above method is 32.0%~35.0%, the MgO mass content is 0.2%~0.8%, and the aluminum-iron sesquioxide (R2O3) mass content is 2.0%~2.6%.

[0017] Compared with the prior art, the present invention has the following beneficial effects: In the present invention: the mineral composition of high-sesquioxide silico-calcium collophanite is single, the phosphorus-containing minerals are mainly low-carbon fluoroapatite, a small amount of carbon apatite and apatite, the magnesium-containing gangue minerals are mainly carbonate minerals, the aluminum-containing gangue minerals are mainly clay silicate minerals such as hydromica and kaolin, and the iron-containing gangue minerals are mainly pyrite. Among them, the grindability of collophanite and quartz is poor, the grindability of dolomite, hydromica and kaolin is good, and the conventional crushing and grinding process is prone to over-grinding. Adding a section of high-pressure roller ultra-fine crushing operation between fine crushing and grinding can improve the particle size composition of subsequent grinding products, provide a good sorting environment for subsequent re-selection, and divide them into high and low grade products after re-selection, respectively adopting a single reverse flotation demagnesium process and a forward and reverse flotation process, compared with the full-material forward and reverse flotation, the grinding cost can be lower by about 50%, and the reagent cost can be reduced by about 50%. The single reverse flotation process can remove iron and magnesium at the same time by adding xanthate as an auxiliary collector. Adding a desludging operation before the direct flotation desiliconization flotation can effectively remove fine mud materials of 10μm, reduce the stability of the foam in the subsequent direct flotation operation, and facilitate the smooth process of the direct flotation desiliconization process. The return water process adopts a separate return water, and the wastewater generated by each operation is returned to its own operation as much as possible through thickening, effectively avoiding the interference of different mineral processing processes.

[0018] The method of the present invention is mainly aimed at high-grade high-sesquisilicon calcium collophosphate ore, and adopts gravity flotation combined separation and quality separation branch flotation. The raw ore is separated into gravity separation concentrate with P2O5 above 33% and gravity separation tailings with P2O5 below 22% by gravity separation equipment. The gravity separation tailings are used for forward and reverse flotation to obtain heavy tailings flotation concentrate with P2O5 above 31%. The separation process fully utilizes the respective advantages of forward and reverse flotation and gravity separation, and realizes high-quality high-use of phosphate concentrate and energy-use of low-quality phosphate concentrate. DETAILED DESCRIPTION

[0019] Example 1, Experiment 1 of the beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite: (1) The feed particle size of the original ore is -600mm. Conventional crushing adopts three-stage open-circuit crushing. The first stage uses a jaw crusher, and the last two stages use a cone crusher to crush the material to -30mm. The crushed material is sent to the screening operation before fine crushing. The screening equipment uses a relaxation screen. The material on the screen is fed to the high-pressure roller mill. The material after high-pressure roller crushing returns to the screening operation to form a closed-circuit ultra-fine crushing and screening. The material under the screen is fed to the powder ore bin, and the screening particle size is controlled at -3mm.

[0020] (2) The materials at the bottom of the powder ore bin are quantitatively fed to the grinding and classification operation by a disc feeder. The grinding adopts one-stage grinding, and the classification adopts primary pre-classification and secondary control classification. The disc feeder adopts frequency conversion speed regulation. The grinding operation adopts a grid-type ball mill. The primary pre-classification adopts a hydrocyclone. The secondary control classification operation adopts two-stage classification. The particle size of the primary pre-classification and the secondary cyclone classification is controlled at 74μm. The first stage adopts a micro powder screen, and the sieve hole particle size is controlled at 0.15mm. The grinding fineness of the material before gravity separation is controlled at 60%, and the qualified particle size of the classification operation is fed into the gravity separation buffer tank; (3) The slurry in the gravity separation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings. The conveying pump adopts frequency conversion speed regulation. The gravity separation operation adopts two-stage classification plus one-stage gravity separation. The two-stage classification adopts a cyclone + micro powder screen. The cyclone is controlled at 38μm and the micro powder screen is controlled at 0.5mm. The gravity separation adopts a spiral chute for primary roughing and a spiral chute for primary scavenging, and finally produces gravity separation concentrate and gravity separation tailings. (4) The gravity separation concentrate is directly fed to the dewatering operation. The dewatering operation uses a vacuum belt filter. The filtrate of the belt filter returns to the gravity separation tailings thickener. The filter cake is fed into the reverse flotation demagnesium buffer tank after slurry adjustment. The gravity separation tailings are fed to the gravity tailings thickener operation. The overflow of the gravity separation tailings thickener returns to the gravity separation return pool. The thickener bottom flow is fed to the tailings regrinding and classification operation. The ground slurry is fed to the positive flotation desiliconization operation buffer tank. The gravity separation tailings are regrinded and ground by a tower mill to further separate useful minerals and gangue minerals. The grinding fineness is -200 mesh 90%. Phosphoric acid is used as a reverse flotation depressant, and a combination of PA-64 and butyl xanthate is used as a collector. The ratio is 2:1. The reverse flotation operation adopts one roughing and one scavenging. (5) The direct flotation desiliconization buffer tank is first fed into the direct flotation desliming operation, and the deslimed pulp is fed into the direct flotation desiliconization operation. The concentrate of the direct flotation desiliconization is fed into the reverse flotation demagnesization operation. The tailings of the direct flotation and the tailings of the desliming flotation are fed into the direct flotation tailings dewatering operation. The concentrate of the reverse flotation is fed into the reverse flotation concentrate dewatering operation. The tailings of the reverse flotation are fed into the reverse flotation tailings dewatering operation. The filtrate of the direct flotation dewatering operation is returned to the direct flotation return water tank. The concentrate and tailings dewatering operation of the reverse flotation are returned to the reverse flotation dewatering operation. The collectors of the direct flotation desliming operation are polyacrylamide and 2# medicine. The alkaline adjuster of the direct flotation operation is sodium carbonate as the pH adjuster, water glass as the inhibitor, and the collector is 2# medicine. The direct flotation operation includes a roughing operation and a fine operation.

[0021] (6) The whole plant has three return water tanks, which store the return water from direct flotation desiliconization, gravity separation and reverse flotation demagnesiumization respectively. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used for the direct flotation desiliconization process. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used for the direct flotation desiliconization process.

[0022] The ore composition of the high-sesquioxide type collophanite in the above method is 29.46% P2O5 grade, 1.20% MgO mass content, 14.80% SiO2 mass content, 1.59% Al2O3 mass content, and 1.38% Fe2O3 mass content; The P2O5 grade of the collophanite concentrate obtained by the above method is 33.20%, the MgO mass content is 0.55%, and the sesquioxide (R2O3) mass content is 2.05%.

[0023] Example 2, Experiment 2 of the beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite: (1) The feed particle size of the original ore is -350mm. Conventional crushing adopts two-stage open-circuit crushing. The first stage crushing adopts jaw crusher and the second stage crushing adopts cone crusher to crush the material to -30mm. The crushed material is sent to the screening operation before fine crushing. The screening equipment uses relaxation screen. The material on the screen is sent to the high-pressure roller mill. The material after high-pressure roller crushing returns to the screening operation to form a closed-circuit ultra-fine crushing and screening. The material under the screen is sent to the powder ore bin. The screening particle size is controlled at -3mm.

[0024] (2) The materials at the bottom of the powder ore bin are quantitatively fed to the grinding and classification operation by a disc feeder. The grinding adopts one-stage grinding, and the classification adopts one-time control classification. The disc feeder adopts frequency conversion speed regulation, the grinding operation adopts rod mill, and the one-time control classification operation adopts cyclone classification. The classification particle size is controlled at 74μm, and the grinding fineness of the material before gravity separation is controlled at 65%. The qualified particle size of the classification operation is fed into the gravity separation operation buffer tank; (3) The slurry in the gravity separation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings. The conveying pump adopts frequency conversion speed regulation. The gravity separation operation adopts one-stage classification plus one-stage gravity separation. The classification adopts a cyclone, and the cyclone is controlled at 38μm. The gravity separation adopts interference bed one-time roughing and spiral chute one-time scavenging, and finally produces gravity separation concentrate and gravity separation tailings; (4) The gravity separation concentrate is directly fed to the dehydration operation. The dehydration operation uses a vacuum belt filter. The filtrate of the belt filter is returned to the gravity separation tailings thickener. The filter cake is fed into the reverse flotation magnesium removal buffer tank after slurry adjustment. The gravity separation tailings are fed to the gravity tailings thickener operation. The overflow of the gravity separation tailings thickener returns to the gravity separation return pool. The thickener bottom flow is directly fed to the direct flotation operation. The grinding fineness is -200 mesh 95%. Sulfuric acid is used as the reverse flotation depressant, and the collector is a combination of PA-64 and butyl xanthate, with a ratio of 2:1. The reverse flotation operation adopts one roughing and one scavenging. (5) The positive flotation desiliconization buffer tank is fed into the positive flotation desiliconization operation, the concentrate of the positive flotation desiliconization is fed into the reverse flotation demagnesium operation, the tailings of the positive flotation are fed into the positive flotation tailings dewatering operation, the concentrate of the reverse flotation is fed into the reverse flotation concentrate dewatering operation, the tailings of the reverse flotation are fed into the reverse flotation tailings dewatering operation, the filtrate of the positive flotation dewatering operation is returned to the positive flotation return water tank, and the filtrate of the reverse flotation concentrate and tailings dewatering operation is returned to the reverse flotation dewatering operation. The alkaline adjuster for the positive flotation operation is sodium carbonate as the pH adjuster, water glass as the inhibitor, and the collector is 2# medicine. The positive flotation operation includes a roughing operation and a fine selection operation.

[0025] (6) The whole plant has three return water tanks, which store the return water from direct flotation desiliconization, gravity separation and reverse flotation demagnesiumization. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation and gravity separation tailings regrinding. The return water from the reverse flotation operation can only be used for the direct flotation desiliconization process after being treated as double alkali process. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation. The return water from the reverse flotation operation can only be used for direct flotation.

[0026] In the above method, the ore composition of the high-sesquioxide type collophanite is 27.98% P2O5, 1.50% MgO, 15.60% SiO2, 1.85% Al2O3 and 1.65% Fe2O3; The P2O5 grade of the collophanite concentrate obtained by the above method is 31.50%, the MgO mass content is 0.75%, and the sesquioxide (R2O3) mass content is 2.45%.

[0027] Example 3, Experiment 3 of the beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite: (1) The feed particle size of the raw ore is -500mm. The conventional crushing adopts three-stage open circuit crushing. The first stage crushing adopts hammer crusher, and the second stage crushing adopts cone crusher to crush the material to -20mm. The crushed material is fed to fine crushing operation. The screening equipment uses relaxation screen. The material on the screen is fed to high pressure roller mill, and the material under the screen is fed to powder ore bin. The screening particle size is controlled at -3mm.

[0028] (2) The materials at the bottom of the powder ore bin are quantitatively fed to the grinding and classification operation by a disc feeder. The grinding adopts a single-stage grinding, and the classification adopts a primary pre-classification and a secondary control classification. The disc feeder adopts frequency conversion speed regulation. The grinding operation adopts a rod mill or a grate ball mill. The primary pre-classification adopts a hydrocyclone, and the secondary control classification operation adopts a cyclone classification. The classification particle size is controlled at 74μm, and the grinding fineness of the material before gravity separation is controlled at 55%. The qualified particle size of the classification operation is fed into the gravity separation operation buffer tank; (3) The slurry in the gravity separation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings. The conveying pump adopts frequency conversion speed regulation. The gravity separation operation adopts two-stage classification plus one-stage gravity separation. The two-stage classification adopts a cyclone + micro powder screen. The cyclone is controlled at 38μm and the micro powder screen is controlled at 0.5mm. The gravity separation adopts a spiral chute for primary roughing and a spiral chute for primary scavenging, and finally produces gravity separation concentrate and gravity separation tailings. (4) The gravity separation concentrate is directly fed to the dewatering operation. The dewatering operation uses a vacuum belt filter. The filtrate of the belt filter returns to the gravity separation tailings thickener. The filter cake is fed into the reverse flotation demagnesium buffer tank after slurry adjustment. The gravity separation tailings are fed into the gravity tailings thickener operation. The overflow of the gravity separation tailings thickener returns to the gravity separation return pool. The thickener bottom flow is fed into the tailings regrinding and classification operation. The ground slurry is fed into the positive flotation desiliconization operation buffer tank. The gravity separation tailings are regrinded and ground by a ball mill to further separate useful minerals and gangue minerals. The grinding fineness is -200 mesh 90%. The reverse flotation depressant is a mixture of phosphoric acid and sulfuric acid in a ratio of 1:1. The collector is a combination of PA-64 and butyl xanthate in a ratio of 2:1. The reverse flotation operation adopts one coarse selection and one scavenging selection; (5) The direct flotation desiliconization buffer tank is first fed into the direct flotation desliming operation, and the deslimed pulp is fed into the direct flotation desiliconization operation. The concentrate of the direct flotation desiliconization is fed into the reverse flotation demagnesization operation. The tailings of the direct flotation and the tailings of the desliming flotation are fed into the direct flotation tailings dewatering operation. The concentrate of the reverse flotation is fed into the reverse flotation concentrate dewatering operation. The tailings of the reverse flotation are fed into the reverse flotation tailings dewatering operation. The filtrate of the direct flotation dewatering operation is returned to the direct flotation return water tank. The concentrate and tailings dewatering operation of the reverse flotation are returned to the reverse flotation dewatering operation. The collectors of the direct flotation desliming operation are polyacrylamide and 2# medicine. The alkaline adjuster of the direct flotation operation is sodium carbonate as the pH adjuster, water glass as the inhibitor, and the collector is 2# medicine. The direct flotation operation includes a roughing operation and a fine operation.

[0029] (6) The whole plant has three return water tanks, which store the return water from direct flotation desiliconization, gravity separation and reverse flotation demagnesiumization respectively. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used for the direct flotation desiliconization process. The return water from the gravity separation return water tank can be used for the first grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization after being treated as qualified. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used for the direct flotation desiliconization process.

[0030] The ore composition of the high-sesquioxide type collophanite in the above method is P2O5 grade of 28.58%, MgO mass content of 1.35%, SiO2 mass content of 15.20%, Al2O3 mass content of 2.15%, Fe2O3 mass content of 1.58%; The P2O5 grade in the collophanite concentrate obtained by the above method is 32.75%, the MgO mass content is 0.85%, and the sesquioxide (R2O3) mass content is 2.45%.

[0031] Example 4, a comparative experiment on the beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite: Ore: The ore composition of high-semioxide type collophanite is P2O5 grade of 29.46%, MgO mass content of 1.20%, SiO2 mass content of 14.80%, Al2O3 mass content of 1.59%, Fe2O3 mass content of 1.38%; Crushing and grinding process: The particle size of the raw ore is -300mm. Conventional crushing adopts two-stage open-circuit crushing. The first stage crushing adopts jaw crusher, and the second stage crushing adopts cone crusher to crush the material to -30mm. The crushed material is sent to the screening operation before fine crushing. The screening equipment adopts relaxation screen. The material on the screen is sent to the high-pressure roller mill. The material crushed by the high-pressure roller is returned to the screening operation to form a closed-circuit ultra-fine crushing and screening. The material under the screen is sent to the powder ore bin, and the screening particle size is controlled at -3mm. The material at the bottom of the powder ore bin is quantitatively fed to the grinding and classification operation by the disc feeder. The grinding adopts one-stage grinding. The classification adopts one-time pre-classification and secondary control classification. The disc feeder adopts frequency conversion speed regulation. The grinding operation adopts rod mill or grid ball mill. The first pre-classification adopts hydrocyclone, and the secondary control classification operation adopts cyclone classification. The classification particle size is controlled at 74μm. The grinding fineness of the material before gravity separation is controlled at 65%, and the qualified particle size of the classification operation is fed to the subsequent sorting operation.

[0032] Among them, the double reverse flotation process and the combined re-flotation-quality separation flotation process, the forward and reverse flotation process must grind the ore to a fineness of -74μm, accounting for 75%.

[0033] Combined re-flotation and quality-separation branch flotation process: The qualified particle size of the grinding and classification operation is fed into the gravity separation operation buffer tank. The slurry in the gravity separation operation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings. The conveying pump adopts frequency conversion speed regulation. The gravity separation operation adopts two-stage classification plus one-stage gravity separation. The two-stage classification adopts cyclone + micro powder screen. The cyclone is controlled at 38μm and the micro powder screen is controlled at 0.5mm. The gravity separation adopts spiral chute for one roughing and spiral chute for one sweeping, and finally produces gravity separation concentrate and gravity separation tailings; the gravity separation concentrate is directly It is fed to the dehydration operation, and a vacuum belt filter is used for the dehydration operation. The filtrate of the belt filter is returned to the gravity separation tailings thickener. The filter cake is fed into the reverse flotation demagnesium buffer tank after slurry adjustment. The gravity separation tailings are fed to the heavy tailings thickener operation. The overflow of the gravity separation tailings thickener is returned to the gravity separation return water tank. The underflow of the thickener is fed to the tailings regrinding and grading operation. The ground slurry is fed to the direct flotation desiliconization operation buffer tank. The gravity separation tailings are regrinded and ground by a ball mill to achieve further dissociation of useful minerals and gangue minerals. The grinding fineness is -200 mesh 90%. The reverse flotation depressant is a mixture of phosphoric acid and sulfuric acid in a ratio of 1:1, the collector is a combination of PA-64 and butyl xanthate in a ratio of 2:1, and the reverse flotation operation adopts one coarse selection and one scavenging selection; the direct flotation desiliconization buffer tank is first fed into the direct flotation desliming operation, and the deslimed slurry is then fed into the direct flotation desiliconization operation, the direct flotation desiliconization concentrate is fed into the reverse flotation demagnesization operation, the direct flotation tailings and the desliming flotation tailings dewatering operation are fed into the direct flotation tailings dewatering operation, the reverse flotation concentrate is fed into the reverse flotation concentrate dewatering operation, the reverse flotation tailings is fed into the reverse flotation tailings dewatering operation, the filtrate of the direct flotation dewatering operation is returned to the direct flotation return water tank, and the reverse flotation concentrate and tailings dewatering operation and the filtrate are returned to the reverse flotation dewatering operation. The collectors for direct flotation desludging are polyacrylamide and 2# medicine. The alkaline adjuster for direct flotation is sodium carbonate as pH adjuster, water glass as inhibitor, and 2# medicine as collector. The direct flotation operation includes one roughing and one fine selection. The whole plant has three return water pools, which store the return water of direct flotation desiliconization, gravity separation return water pool and reverse flotation demagnesium return water respectively. The return water of gravity separation return water pool can be used for one-stage grinding and gravity separation. The return water of reverse flotation demagnesium return water pool is used for reverse flotation demagnesium, and the other part is used for direct flotation desiliconization after qualified treatment. The return water of direct flotation desiliconization return water pool can only be used for direct flotation and gravity separation tailings regrinding. The return water of reverse flotation operation can only be used for direct flotation desiliconization after double alkali process treatment. The return water from the gravity separation return water tank can be used for the first stage grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization operation after qualified treatment. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used in the direct flotation desiliconization process.

[0034] Direct and reverse flotation: The qualified particle size of the grinding and classification operation is fed into the direct flotation desiliconization buffer tank. The direct flotation operation uses alkaline adjusters, sodium carbonate as pH adjusters, water glass as depressants, and 2# medicine as collectors. The direct flotation operation includes one roughing and one fine selection operation. The direct flotation concentrate is fed into the reverse flotation demagnesium operation. The reverse flotation depressor uses phosphoric acid and sulfuric acid mixed acid with a ratio of 1:1. The collector uses a combination of PA-64 and butyl xanthate with a ratio of 2:1. The reverse flotation operation uses one roughing and one scavenging. Two return water tanks are built in the whole plant to store the return water of direct flotation desiliconization and the return water of reverse flotation demagnesiumization. Part of the return water of the reverse flotation demagnesium return water tank is used for reverse flotation demagnesium operation, and the other part is used for direct flotation desiliconization after being treated and qualified. The return water of the direct flotation desiliconization return water tank is used for direct flotation operation. The return water of the reverse flotation operation must be treated by the double alkali process before it can be used in the direct flotation desiliconization process.

[0035] Desliming-reverse flotation process: The qualified particle size of the grinding and classification operation is first fed into the cyclone desliming operation to remove the -38μm material, and the cyclone underflow is fed into the reverse flotation demagnesing flotation operation. The reverse flotation demagnesing inhibitor uses phosphoric acid and sulfuric acid mixed acid with a ratio of 1:1, and the collector uses a combination of PA-64 and butyl xanthate with a ratio of 2:1. The reverse flotation demagnesing concentrate slurry is fed into the reverse flotation desiliconization operation. The reverse flotation desiliconization operation uses MAC as a collector. The reverse flotation operation includes a roughing operation and a fine sweeping operation. The cyclone overflow and the reverse flotation desiliconization concentrate are mixed and dehydrated to obtain the final concentrate. Two return water pools are built in the whole plant, which store reverse flotation desiliconization return water and reverse flotation demagnesiumization return water respectively. Part of the return water from the reverse flotation desiliconization return water pool is used for reverse flotation desiliconization operation, and the other part is used for reverse flotation demagnesiumization operation after qualified treatment. The return water from the reverse flotation demagnesiumization return water pool is used for reverse flotation demagnesiumization operation.

[0036] The following table compares the cost and product technical indicators of the process of the present invention with those of the conventional forward and reverse flotation process and double reverse flotation process: .

Claims

1. A beneficiation method for removing iron-aluminum sesquioxide from high-grade collophanite, characterized in that: The steps are as follows: (1) The medium-high aluminum siliceous colloidal phosphate ore is crushed, then ultra-finely crushed and screened to -3mm before being fed into the powder ore bin; (2) The materials at the bottom of the powder ore bin are fed into the grinding and classification process by a disc feeder and then into the gravity separation buffer tank; (3) The slurry in the gravity separation buffer tank is fed to the gravity separation operation through a conveying pump to obtain gravity separation concentrate and gravity separation tailings; (4) The gravity separation concentrate is fed into the reverse flotation de-magnesium buffer tank, the gravity separation tailings are fed into the thickener operation, the thickener underflow is fed into the tailings regrinding and classification operation, and the ground slurry is fed into the direct flotation de-siliconization buffer tank; (5) The positive flotation desiliconization buffer tank is first fed into the positive flotation desliming operation, and the deslimed ore pulp is then fed into the positive flotation desiliconization operation. The concentrate from the positive flotation desiliconization is fed into the reverse flotation demagnesization operation. The tailings from the positive flotation and the desliming flotation tailings are fed into the positive flotation tailings dewatering operation. The concentrate from the reverse flotation is fed into the reverse flotation concentrate dewatering operation, and the tailings from the reverse flotation is fed into the reverse flotation tailings dewatering operation. Three return water tanks are built to store the return water from the positive flotation desiliconization, the return water from the gravity separation, and the return water from the reverse flotation demagnesization. The medium-high aluminum siliceous collophosphate ore group has a P2O5 grade of 27.5%~29.8%, a MgO mass content of 1.1%~2.5%, a SiO2 mass content of 11.5%~14.5%, an Al2O3 mass content of 1.5%~3.0%, and a Fe2O3 mass content of 1.2%~2.5%.

2. A method for beneficiating high-grade collophanite from aluminum sesquioxide according to claim 1, characterized in that: In ultra-fine crushing and screening, high-pressure roller mill is used for ultra-fine crushing, and relaxation screen is used for screening.

3. A method for beneficiating high-grade collophanite from aluminum sesquioxide according to claim 1, characterized in that: The grinding and classification operation adopts rod mill or grate ball mill for grinding. The grinding and classification adopts two-stage classification. The first stage adopts micro powder screen or fine screen, and the screen hole particle size is controlled at 0.1~0.15mm. The second stage adopts cyclone classification, and the classification particle size is controlled at 74μm. The grinding fineness of the material before flotation is controlled at 55%~65%.

4. A method for beneficiating high-grade collophanite from deironized aluminum sesquioxide according to claim 1, characterized in that: The gravity separation operation adopts two-stage classification plus one-stage gravity separation. The two-stage classification adopts cyclone + micro powder screen. The cyclone is controlled at 10~38μm, and the micro powder screen is controlled at 0.5~1mm. The gravity separation uses one or a combination of interference bed, shaking table, spiral chute, belt chute and centrifugal concentrator. The gravity separation operation includes roughing, cleaning or scavenging.

5. A method for beneficiating high-grade collophanite from aluminum sesquioxide according to claim 1, characterized in that: The reverse flotation magnesium removal process mainly removes carbonate minerals. The depressant is sulfuric acid, phosphoric acid, phosphate or a combination of the above agents. The collector is a combination of fatty acid soap and xanthate. The reverse flotation operation includes roughing and scavenging.

6. A method for beneficiating high-grade collophanite from deironized aluminum sesquioxide according to claim 1, characterized in that: Before the direct flotation desiliconization operation, flotation desludging operation is added, and polyacrylamide and 2# medicine are selected as collectors.

7. A method for beneficiating high-grade collophanite from aluminum sesquioxide according to claim 1, characterized in that: The positive flotation operation mainly removes mud silicate gangue minerals. The flotation environment is alkaline. Sodium carbonate is used as the pH adjuster, water glass is used as the inhibitor, and unsaturated fatty acid organic matter is used as the collector. The positive flotation operation includes roughing and cleaning operations.

8. A method for beneficiating high-grade collophanite from aluminum sesquioxide according to claim 1, characterized in that: The re-grinding and classification operation of the gravity separation tailings uses a tower mill to grind the ore to further separate the useful minerals and gangue minerals. The grinding fineness is -200 mesh 85%~95%.

9. A method for beneficiating high-grade collophanite from aluminum sesquioxide according to claim 1, characterized in that: The return water from the gravity separation return water tank is used for the first stage grinding operation and gravity separation operation. Part of the return water from the reverse flotation demagnesiumization return water tank is used for reverse flotation demagnesiumization operation, and the other part is used for direct flotation desiliconization operation after qualified treatment. The return water from the direct flotation desiliconization return water tank can only be used for direct flotation operation and gravity separation tailings regrinding operation. The return water from the reverse flotation operation must be treated by the double alkali process before it can be used in the direct flotation desiliconization process.