Reverse and direct flotation process for removing iron, aluminum, magnesium and silicon from phosphorite

Abstract

The invention relates to the technical field of collophanite beneficiation, and discloses a reverse and direct flotation process for removing iron, aluminum, magnesium and silicon from phosphorite, which comprises the following steps: carrying out reverse flotation magnesium removal, activation iron and aluminum removal and direct flotation desilicication treatment on the phosphorite to obtain phosphate concentrate; by means of the process, magnesium, iron, aluminum and silicon impurities in collophanite can be gradually removed, and the quality of phosphate concentrate products is improved. According to the method, fine-fraction iron and aluminum impurities can be separated from the phosphorite through a reverse flotation process and a direct flotation process and the activation effect of alkali metal ions, so that the argillization effect in the desilicication process is reduced, the flotation desilicication environment is improved, the desilicication efficiency is improved, and finally, various gangue minerals in the collophanite are sequentially removed.

Description

Technical Field

[0001] The invention relates to the technical field of collophanite beneficiation, and in particular to a reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore. Background Art

[0002] The main gangue mineral in phosphate ore is dolomite, and the main components of siliceous gangue minerals are quartz, aluminate minerals, limonite, etc. At present, the industry mainly uses reverse flotation to remove dolomite, while silicon, aluminum, and iron gangue minerals cannot be effectively removed and are enriched in phosphate concentrate, which has a great impact on downstream industries. With the gradual consumption of phosphate resources, high-quality phosphate resources are becoming increasingly scarce, and simple magnesium removal has gradually failed to meet the needs of industrial applications. It is necessary to further reduce the content of gangue minerals such as iron, aluminum, and silicon in concentrated phosphate ore and improve the quality of phosphate concentrate.

[0003] Fine-grained minerals have small particles, large specific surface area, and high surface energy, which affect the interaction between reagents and minerals during flotation, resulting in poor separation results. Iron and aluminum ions in phosphate ore are mainly concentrated in fine-grained minerals, while siliceous gangue minerals are mainly concentrated in coarse-grained minerals due to their relatively high hardness. Removing a portion of fine-grained iron-aluminum gangue minerals in the flotation process will greatly promote the subsequent desiliconization flotation process and is of great significance to improving the quality of phosphate concentrate. Summary of the invention

[0004] The purpose of the present invention is to provide a reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore, which gradually removes magnesium, iron, aluminum and silicon impurities from collophanite, thereby improving the quality of phosphate concentrate products. Through the reverse flotation process and the activation of alkali metal ions, fine-grained iron and aluminum impurities can be separated from the phosphate ore, thereby reducing the mudding effect in the desiliconization process, improving the flotation desiliconization environment, and improving the desiliconization efficiency, and finally realizing the sequential removal of various gangue minerals in the collophanite.

[0005] The scheme of the present invention is:

[0006] The invention discloses a reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore, which obtains phosphate concentrate by subjecting the phosphate ore to reverse flotation for removing magnesium, activation for removing iron and aluminum and direct flotation for removing silicon.

[0007] As a preferred technical solution, magnesium is removed by weakly acidic reverse flotation, iron and aluminum minerals are removed by activated positive flotation in neutral slurry, and the SiO2 content is reduced by weakly alkaline positive flotation of phosphate minerals.

[0008] As a preferred technical solution, the reverse flotation demagnesium process is as follows:

[0009] The collophanite is crushed and then ground to a flotation slurry with a content of ≥85% of -0.074 mm and a concentration of 20% to 25%;

[0010] Adding pH adjusting agent sulfuric acid and a collector to the flotation raw ore pulp, and after pulping, performing a reverse flotation roughing selection, a reverse flotation cleaning selection and a third reverse flotation sweeping selection to obtain reverse flotation tailings and de-magnesiumized phosphate concentrate pulp;

[0011] The concentrate after reverse flotation roughing is sent to the reverse flotation selection, and the tailings after reverse flotation roughing are sent to reverse flotation scavenging; the reverse flotation scavenging includes the first reverse flotation scavenging, the second reverse flotation scavenging and the third reverse flotation scavenging, a collector is added during the reverse flotation selection, and sulfuric acid is added in the reverse flotation scavenging; the ore from the first reverse flotation scavenging is mixed with the tailings from the reverse flotation selection and returned to the reverse flotation roughing process; the ore from the second reverse flotation scavenging is returned to the first reverse flotation scavenging process, and the ore from the third reverse flotation scavenging is returned to the second reverse flotation scavenging process.

[0012] As a preferred technical solution, the collophanite is a collophanite with a P2O5 content of 18% to 22%, a MgO content of 5 to 6.5%, and a sesquioxide (Fe2O3+Al2O3) content of 2 to 4%.

[0013] As a preferred technical solution, the amount of sulfuric acid in the reverse flotation roughing process is 20-23 kg / t, the amount of collector in the reverse flotation roughing process is 0.4-0.6 kg / t, the amount of sulfuric acid in the first reverse flotation scavenging process is 8-10 kg / t, the amount of sulfuric acid in the second reverse flotation scavenging process is 2-4 kg / t, the amount of sulfuric acid in the third reverse flotation scavenging process is 2-4 kg / t, the amount of collector in the reverse flotation concentrating process is 0.1-0.3 kg / t; the collector is LAA-T.

[0014] As a preferred technical solution, the activated de-ironization aluminum is:

[0015] The demagnesized phosphate concentrate slurry obtained after reverse flotation demagnesization is adjusted to a pH value of 6-8 by a pH regulator, and then alkali metal ions are added to activate the minerals. Collectors and synergists are added to float and remove fine-grained iron-aluminum-containing gangue minerals in the phosphate concentrate to obtain deiron-aluminum phosphate concentrate slurry and activated tailings.

[0016] As a preferred technical solution, the mineral is activated 1 to 2 times.

[0017] As a preferred technical solution, the alkali metal ion is Mg 2+ or Ca 2+ .

[0018] As a preferred technical solution, the pH adjuster is one of Na2CO3 and CaO; when the pH adjuster is Na2CO3, its usage is 4-7kg / t; when the pH adjuster is CaO, its usage is 7-7.5kg / t.

[0019] As a preferred technical solution, the collector is a phosphate ester surfactant, and the phosphate ester surfactant is one or more of isomeric tridecyl alcohol polyoxyethylene ether phosphatidic acid, isooctyl alcohol polyoxyethylene ether sodium phosphate, fatty alcohol polyoxyethylene ether phosphate, octyl alcohol polyoxyethylene ether potassium phosphate, dodecyl polyoxyethylene ether potassium phosphate and lauryl alcohol potassium phosphate.

[0020] As a preferred technical solution, the synergist is a phosphate surfactant. When the phosphate surfactant is tributyl phosphate, the amount thereof is 100 to 200 g / t.

[0021] As a preferred technical solution, the positive flotation desiliconization treatment is:

[0022] Inhibitors, collectors and synergists are sequentially added to the de-ironized aluminum phosphate concentrate slurry, and after sufficient mixing and slurry preparation, direct flotation is performed to obtain phosphate concentrate and direct flotation phosphate tailings. The foam product in the direct flotation is phosphate concentrate, and the product in the flotation tank is de-siliconized phosphate tailings.

[0023] The grade of phosphate concentrate is greater than 30%, the recovery rate of P2O5 is greater than 80%, and the MER is less than 0.09.

[0024] As a preferred technical solution, the inhibitor is water glass, and its dosage is 1-2 kg / t; the collector is isomeric tridecanol polyoxyethylene ether phosphatidic acid, and its dosage is 300-400 g / t; the synergist is tributyl phosphate, and its dosage is 100-200 g / t.

[0025] Advantages of the present invention:

[0026] The process of the present invention can gradually remove magnesium, iron, aluminum and silicon impurities in the collophanite, thereby improving the quality of the phosphate concentrate product. Through the reverse flotation process and the activation of alkali metal ions, fine-grained iron and aluminum impurities can be separated from the phosphate ore, thereby reducing the mudding effect in the desiliconization process, improving the flotation desiliconization environment, and improving the desiliconization efficiency, and finally realizing the sequential removal of various gangue minerals in the collophanite. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a process flow chart of Example 1 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0029] Example 1

[0030] In this embodiment, the reverse flotation process of removing iron, aluminum, magnesium and silicon is applied to the collophanite with a P2O5 content of 21.40%, a MgO content of 5.83%, a sesquioxide content of 2.41% and a SiO2 content of 16.51%. The process flow is shown in Figure 1 , the specific process steps are as follows:

[0031] (1) Slurry preparation process

[0032] The collophanite is crushed and ground to -0.074 mm, with a content of 87% and a concentration of 22% to obtain a flotation slurry;

[0033] (2) Magnesium removal process

[0034] pH adjuster sulfuric acid and collector LAA-T were added to the slurry. After slurry adjustment, one reverse flotation roughing, one reverse flotation cleaning and three reverse flotation scavenging were carried out. The middlings from scavenging 1 (the first reverse flotation scavenging) were mixed with the cleaned tailings and returned to the roughing process. The middlings from scavenging 2 (the second reverse flotation scavenging) and scavenging 3 (the third reverse flotation scavenging) were returned to the previous scavenging process in sequence to obtain a demagnesized phosphate concentrate with a P2O5 content of 27.55% and a MgO content of 1.03%. The P2O5 content of the reverse flotation tailings 1 was 5.02%.

[0035] (3) Two-activation de-ironization process

[0036] The demagnesiumized phosphate concentrate was prepared by adding Na2CO3 to adjust the slurry pH to 7. After the first addition of 5% MgCl2 alkali metal ion solution for 1 minute activation, collector E1310P (isomeric tridecanol polyoxyethylene ether phosphatidic acid) and tributyl phosphate were added. After sufficient mixing and slurry adjustment, the fine-grained iron-aluminum-containing gangue minerals in the phosphate concentrate were removed by direct flotation to obtain deiron-aluminumized phosphate concentrate 1 with a P2O5 content of 28.04% and activated reverse flotation tailings 1 with a P2O5 content of 25.27%.

[0037] MgCl2 alkali metal ion solution with a concentration of 5% was added to the pulp of the de-iron aluminum phosphate concentrate 1 again, and the alkali metal ion solution was activated again for 1 minute, and then the collector E1310P and tributyl phosphate were added, and after sufficient mixing and slurry adjustment, the de-iron aluminum phosphate concentrate 2 with a P2O5 content of 29.73% and the activated reverse flotation tailings 2 with a P2O5 content of 28.72% were obtained by flotation;

[0038] (4) Desiliconization process

[0039] After adding the inhibitor water glass, collector E1310P and tributyl phosphate to the slurry of the de-ironized aluminum phosphate concentrate 2 and fully mixing and slurrying, the final phosphate concentrate with a P2O5 content of 31.36%, a MgO content of 0.61%, a sesquioxide content of 1.49%, and a SiO2 content of 15.86% was obtained, and the P2O5 content of the positive flotation tailings was 5.68%.

[0040] In the above example, the amount of sulfuric acid used in the reverse flotation roughing is 21kg / t, and the amount of LAA-T used is 0.4kg / t; the amounts of sulfuric acid used in the three scavengings are 9kg / t, 3kg / t, and 3kg / t respectively; the amount of LAA-T used in the reverse flotation cleaning is 0.15kg / t; the amount of Na2CO3 used in the activated flotation is 5.6kg / t, the amount of alkali metal ion solution used is 1.4kg / t, and the amounts of E1310P and tributyl phosphate used are 30g / t and 150g / t respectively; the amount of alkali metal ion solution used in the re-activated flotation is 1.4kg / t, and the amounts of E1310P and tributyl phosphate used are 30g / t and 150g / t respectively; the amount of water glass used in the positive flotation desiliconization is 1.4kg / t, and the amounts of E1310P and tributyl phosphate used are 360g / t and 150g / t respectively.

[0041] Example 2

[0042] In this embodiment, a reverse flotation process for removing iron, aluminum, magnesium and silicon is carried out on a collophanite with a P2O5 content of 22%, a MgO content of 5.5% and a sesquioxide content of 3.4%. The specific process steps are as follows:

[0043] (1) Slurry preparation process

[0044] The collophanite is crushed and ground to -0.074 mm, with a content of 88% and a concentration of 22% to obtain a flotation slurry;

[0045] (2) Magnesium removal process

[0046] pH adjuster sulfuric acid and collector LAA-T were added to the slurry. After slurry adjustment, one reverse flotation roughing, one reverse flotation cleaning and three reverse flotation scavenging were carried out. The middlings from scavenging 1 (the first reverse flotation scavenging) were mixed with the cleaned tailings and returned to the roughing process. The middlings from scavenging 2 (the second reverse flotation scavenging) and scavenging 3 (the third reverse flotation scavenging) were returned to the previous scavenging process in sequence to obtain a demagnesized phosphate concentrate with a P2O5 content of 28.06% and a MgO content of 0.87%. The P2O5 content in the reverse flotation tailings 1 was 6.06%.

[0047] (3) One-step activation de-ironization and de-aluminization process

[0048] The magnesium-free phosphate concentrate is prepared by adding Na2CO3 to adjust the pulp pH to 7, and then adding 5% MgCl2 alkali metal ion solution for 1 minute activation, adding collector E1310P and tributyl phosphate, and after sufficient mixing and slurrying, flotation is performed to remove the fine-grained iron-aluminum-containing gangue minerals in the phosphate concentrate to obtain a de-iron-aluminum phosphate concentrate with a P2O5 content of 29.06% and a reverse flotation tailing 2;

[0049] (4) Desiliconization process

[0050] After adding water glass, collector E1310P and tributyl phosphate to the iron-free aluminum phosphate concentrate slurry and fully mixing and slurrying, the final phosphate concentrate with a P2O5 content of 31.67%, a MgO content of 0.9% and a sesquioxide content of 2.5% was obtained, and the P2O5 content of the positive flotation tailings was 7.34%.

[0051] In the above example, the amount of sulfuric acid used in the reverse flotation roughing is 21kg / t, and the amount of LAA-T used is 0.4kg / t; the amounts of sulfuric acid used in the three scavenging selections are 9kg / t, 4kg / t, and 2kg / t respectively; the amount of LAA-T used in the reverse flotation selection is 0.1kg / t; the amount of Na2CO3 used in the activated flotation is 5kg / t, the amount of alkali metal ion solution is 1.5kg / t, and the amounts of E1310P and tributyl phosphate are 35g / t and 150g / t respectively; the amount of desiliconized water glass used in the positive flotation is 1.5kg / t, and the amounts of E1310P and tributyl phosphate are 350g / t and 150g / t respectively.

[0052] Example 3

[0053] In this embodiment, the reverse flotation process of removing iron, aluminum, magnesium and silicon is applied to the collophanite with a P2O5 content of 20.2%, a MgO content of 5.9% and a sesquioxide content of 3.3%. The specific process steps are as follows:

[0054] (1) Slurry preparation process

[0055] The collophanite is crushed and ground to a flotation slurry with a content of 85% and a concentration of 21.22% at -0.074 mm;

[0056] (2) Magnesium removal process

[0057] pH adjuster sulfuric acid and collector LAA-T were added to the slurry. After slurry adjustment, one reverse flotation roughing, one reverse flotation cleaning and three reverse flotation scavenging were carried out. The middlings from scavenging 1 (the first reverse flotation scavenging) were mixed with the cleaned tailings and returned to the roughing process. The middlings from scavenging 2 (the second reverse flotation scavenging) and scavenging 3 (the third reverse flotation scavenging) were returned to the previous scavenging process in sequence to obtain a demagnesized phosphate concentrate with a P2O5 content of 26.35% and a MgO content of 0.8%. The P2O5 content in the reverse flotation tailings 1 was 7.06%.

[0058] (3) One-step activation de-ironization and de-aluminization process

[0059] The magnesium-free concentrate was prepared by adding Na2CO3 to adjust the pulp pH to 7, and then adding 5% MgCl2 alkali metal ion solution for 1 minute activation, adding collector E1310P and tributyl phosphate, and after sufficient mixing and slurrying, flotation was performed to remove the fine-grained iron-aluminum gangue minerals in the phosphate concentrate to obtain a de-iron-aluminum phosphate concentrate with a P2O5 content of 28.46% and a reverse flotation tailing 2;

[0060] (4) Desiliconization process

[0061] After adding water glass, collector E1310P and tributyl phosphate into the de-ironized aluminum phosphate concentrate slurry and mixing them thoroughly, the phosphate concentrate with a P2O5 content of 29.88%, a MgO content of 0.73% and a sesquioxide content of 1.45% was finally obtained, and the P2O5 content of the positive flotation tailings was 9.63%.

[0062] In the above examples, the amount of sulfuric acid used in roughing is 20kg / t, and the amount of LAA-T used in scavenging is 10kg / t, 2kg / t, and 2kg / t; the amount of LAA-T used in cleaning is 0.15kg / t; the amount of Na2CO3 used in normal flotation desliming is 5.8kg / t, alkali metal ion solution is 1.5kg / t, collector E1310P is 30g / t, and tributyl phosphate is 150g / t; the amount of water glass used in normal flotation desiliconization is 2kg / t, collector E1310P is 400g / t, and tributyl phosphate is 150g / t.

[0063] Example 4

[0064] In this embodiment, the reverse flotation process of removing iron, aluminum, magnesium and silicon is applied to the collophanite with a P2O5 content of 19.32%, a MgO content of 6.12% and a sesquioxide content of 3.78%. The specific process steps are as follows:

[0065] (1) Slurry preparation process

[0066] The collophanite is crushed and ground to a flotation slurry with a content of 85% and a concentration of 21.22% at -0.074 mm;

[0067] (2) Magnesium removal process

[0068] pH adjuster sulfuric acid and collector LAA-T were added to the slurry. After slurry adjustment, one reverse flotation roughing, one reverse flotation cleaning and three reverse flotation scavenging were carried out. The middlings from scavenging 1 (the first reverse flotation scavenging) were mixed with the cleaned tailings and returned to the roughing process. The middlings from scavenging 2 (the second reverse flotation scavenging) and scavenging 3 (the third reverse flotation scavenging) were returned to the previous scavenging process in sequence to obtain a demagnesized phosphate concentrate with a P2O5 content of 26.15% and a MgO content of 1.45%. The P2O5 content of the reverse flotation tailings 1 was 8.62%.

[0069] (3) One-step activation de-ironization and de-aluminization process

[0070] The magnesium-free concentrate is prepared by adding Na2CO3 to adjust the pulp pH to 7, and then adding a 5% MgCl2 alkali metal ion solution for 1 minute activation, and then adding E1310P (isomeric tridecanol polyoxyethylene ether phosphatidic acid) and AEO-3p (fatty alcohol polyoxyethylene ether phosphate) in a mass ratio of 1:1 as a collector and a synergist tributyl phosphate. After fully mixing and slurrying, the fine-grained iron-aluminum gangue minerals in the phosphate concentrate are removed by flotation to obtain a de-iron-aluminum phosphate concentrate with a P2O5 content of 27.82% and a reverse flotation tailing 2;

[0071] (4) Desiliconization process

[0072] To the de-iron aluminum phosphate concentrate slurry, water glass, E1310P (isomeric tridecyl alcohol polyoxyethylene ether phosphatidic acid) and AEO-3p (fatty alcohol polyoxyethylene ether phosphate) in a mass ratio of 1:1 were added as a collector and a synergist, tributyl phosphate, which was fully mixed and slurried to finally obtain a phosphate concentrate with a P2O5 content of 28.92%, a MgO content of 1.07% and a sesquioxide content of 1.84%, and the P2O5 content of the positive flotation tailings was 10.35%.

[0073] In the above examples, the amount of sulfuric acid used in roughing is 22kg / t, and the amount of LAA-T used in 0.55kg / t; the amount of sulfuric acid used in scavenging is 9kg / t, 3kg / t, and 3kg / t; the amount of LAA-T used in cleaning is 0.2kg / t; the amount of Na2CO3 used in positive flotation desliming is 6kg / t, alkali metal ion solution is 1.3kg / t, mixed collector is 40g / t, and tributyl phosphate is 150g / t; the amount of water glass used in positive flotation desiliconization is 3kg / t, mixed collector is 450g / t, and tributyl phosphate is 150g / t.

[0074] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore, characterized in that: The method comprises the following steps: performing reverse flotation to remove magnesium, activation to remove iron and aluminum, and direct flotation to remove silicon on the phosphate ore to obtain phosphate concentrate.

2. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore as claimed in claim 1, characterized in that: Magnesium is removed by weak acid reverse flotation, iron and aluminum minerals are removed by activated positive flotation in neutral slurry, and the SiO2 content is reduced by weak alkaline positive flotation of phosphate minerals.

3. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore as claimed in claim 1, characterized in that: The reverse flotation demagnesization is as follows: The collophanite is crushed and then ground to a flotation slurry with a content of ≥85% of -0.074 mm and a concentration of 20% to 25%; Adding pH adjusting agent sulfuric acid and a collector to the flotation raw ore pulp, and after pulping, performing a reverse flotation roughing selection, a reverse flotation cleaning selection and a third reverse flotation sweeping selection to obtain reverse flotation tailings and de-magnesiumized phosphate concentrate pulp; The concentrate after reverse flotation roughing is sent to the reverse flotation cleaning, and the tailings after reverse flotation roughing are sent to reverse flotation scavenging; The reverse flotation scavenging includes a first reverse flotation scavenging, a second reverse flotation scavenging and a third reverse flotation scavenging, a collector is added during the reverse flotation scavenging, and sulfuric acid is added during the reverse flotation scavenging; The first reverse flotation scavenging selected ore is mixed with the reverse flotation selected tailings and returned to the reverse flotation roughing process; The medium-sized materials selected by the second reverse flotation scavenging are returned to the first reverse flotation scavenging process, and the medium-sized materials selected by the third reverse flotation scavenging are returned to the second reverse flotation scavenging process.

4. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore as claimed in claim 3, characterized in that: The amount of sulfuric acid used in the reverse flotation roughing process is 20-23 kg / t, the amount of collector used in the reverse flotation roughing process is 0.4-0.6 kg / t, the amount of sulfuric acid used in the first reverse flotation scavenging process is 8-10 kg / t, the amount of sulfuric acid used in the second reverse flotation scavenging process is 2-4 kg / t, the amount of sulfuric acid used in the third reverse flotation scavenging process is 2-4 kg / t, the amount of collector used in the reverse flotation concentrating process is 0.1-0.3 kg / t; the collector is LAA-T.

5. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore as claimed in claim 1, characterized in that: The activated de-ironization aluminum is: The demagnesized phosphate concentrate slurry obtained after reverse flotation demagnesization is adjusted to a pH value of 6-8 by a pH regulator, and then alkali metal ions are added to activate the minerals. Collectors and synergists are added to float and remove fine-grained iron-aluminum-containing gangue minerals in the phosphate concentrate to obtain deiron-aluminum phosphate concentrate slurry and activated tailings.

6. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore as claimed in claim 5, characterized in that: The pH regulator is one of Na2CO3 and CaO; when the pH regulator is Na2CO3, its usage is 4-7kg / t; when the pH regulator is CaO, its usage is 7-7.5kg / t.

7. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore as claimed in claim 5, characterized in that: The collector is a phosphate surfactant, and the phosphate surfactant is one or more of isomeric tridecyl alcohol polyoxyethylene ether phosphatidic acid, isooctyl alcohol polyoxyethylene ether sodium phosphate, fatty alcohol polyoxyethylene ether phosphate, octyl alcohol polyoxyethylene ether potassium phosphate, dodecyl polyoxyethylene ether potassium phosphate and lauryl alcohol potassium phosphate.

8. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore according to claim 5, characterized in that: The synergist is tributyl phosphate, and the amount thereof is 100-200 g / t.

9. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore according to claim 1, characterized in that: The positive flotation desiliconization process is as follows: Inhibitors, collectors and synergists are added to the de-ironized aluminum phosphate concentrate slurry in sequence, and after sufficient mixing and slurry adjustment, phosphate concentrate and positive flotation phosphate tailings are obtained by direct flotation.

10. The reverse flotation process for removing iron, aluminum, magnesium and silicon from phosphate ore according to claim 9, characterized in that: The inhibitor is water glass, and its dosage is 1-2 kg / t; the collector is isomeric tridecanol polyoxyethylene ether phosphatidic acid, and its dosage is 300-400 g / t; the synergist is tributyl phosphate, and its dosage is 100-200 g / t.

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