Method for comprehensively utilizing high-iron bauxite

Abstract

The invention relates to the field of comprehensive utilization of resources, and discloses a method for comprehensively utilizing high-iron bauxite, which comprises the following steps of: grinding the high-iron bauxite into fine ore, and uniformly mixing the fine ore with a binder and water to form pellets; drying the made pellets at the temperature of 200-300 DEG C until the water content is below 1%; the dried pellets are added into an electric arc furnace and heated to 1500-1600 DEG C for melting, a molten pool is formed, hydrogen is introduced into the molten pool, and molten iron and slag are generated; the molten iron is used for steelmaking or made into castings, and the slag is used for separating and extracting Al2O3, Fe2O3 and SiO2 after water quenching. The high-iron bauxite is reduced through hydrogen, CO2 is not generated, carbon pollution is avoided, after iron is extracted, slag is subjected to water quenching, aluminum, silicon, iron and other components are separated and extracted, various components in the high-iron bauxite can be fully recycled, the recovery rate is high, the comprehensive utilization degree is high, and waste is little.

Description

Technical Field

[0001] The present invention belongs to the field of comprehensive utilization of resources, and particularly relates to a method for comprehensively utilizing high-iron bauxite ore. Background Art

[0002] In China, the resources of iron ore and bauxite are seriously scarce and rely heavily on imports. However, the high-iron bauxite resources in Guangxi, Fujian, Taiwan and other places have not been utilized. This is because in terms of single metals of iron and aluminum contained in high-iron bauxite, neither iron nor aluminum reaches the industrial grade. Therefore, there is no benefit in extracting only iron or only aluminum from this ore, and the path of comprehensive utilization must be taken. For decades, Chinese scientific and technological workers have conducted a large number of studies on high-iron bauxite in China and achieved many results in process technology. Generally speaking, there are three processes: "ore dressing first and then smelting", "aluminum first and then iron", and "iron first and then aluminum".

[0003] The process of ore dressing first and then smelting is to separate aluminum-containing minerals from iron-containing minerals by ore dressing to obtain aluminum concentrate and iron concentrate. Then, the aluminum concentrate is treated by wet method to produce alumina; the iron concentrate is treated by blast furnace to produce iron. Due to the poor crystallization and fine dissemination of high-iron bauxite, conventional ore dressing methods cannot effectively separate aluminum and iron minerals.

[0004] The process of aluminum first and then iron is to treat high-iron bauxite ore by the Bayer process to extract alumina, and then use red mud to smelt iron. However, with this method, the extraction rate of aluminum is low, the smelting cost of iron is high, and the economic benefit is poor.

[0005] The process of iron first and then aluminum is to first extract iron from high-iron bauxite and then extract alumina from the slag. Specifically, there are four schemes: pellet iron scheme; pig iron - clinker scheme; metallization pre-reduction - electric furnace melting - alumina extraction scheme; sintering - blast furnace ironmaking - slag alumina extraction scheme. Among them, the pellet iron scheme and the pig iron - clinker scheme are difficult to implement technically; the metallization pre-reduction - electric furnace melting - alumina extraction scheme and the sintering - blast furnace ironmaking - slag alumina extraction scheme are technically feasible, but the cost is high and there is no economic benefit. Therefore, in order to realize the rational utilization of high-iron bauxite, new process technologies need to be studied. Summary of the Invention

[0006] The object of the present invention is to solve the above problems and provide a method for comprehensively utilizing high-iron bauxite, which uses hydrogen reduction to extract iron, separates and extracts alumina and silica from the slag, with high extraction rate and low cost.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A method for comprehensively utilizing high-iron bauxite ore, comprising the following steps:

[0008] (1) Grind the high-iron bauxite into fine powder ore, mix it evenly with a binder and water to form pellets. If using lump ore of 20 mm - 30 mm, there is no need to make pellets and it can be directly added to the electric arc furnace;

[0009] (2) Dry the made pellets at 200°C - 300°C until the water content is below 1%;

[0010] (3) Add the dried pellets to the electric arc furnace, heat to 1500°C - 1600°C to melt and form a molten pool. Pass hydrogen into the molten pool to generate molten iron and slag. The amount of hydrogen added is 100% in excess of the amount of hydrogen required to completely reduce iron oxides, etc. in the molten pool.

[0011] The chemical reactions that occur are:

[0012] Fe2O3 + H2 = 2FeO + H2O

[0013] FeO + H2 = Fe + H2O

[0014] Al2O3, SiO2, etc. form slag;

[0015] (4) Use the molten iron for steelmaking or casting, and use the water-quenched slag for separating and extracting Al2O3, Fe2O3, and SiO2.

[0016] Preferably, in step (1), the fine powder ore is ground to a powder of about 80 μm, mixed evenly with a binder and water to form pellets of 20 mm - 30 mm.

[0017] Preferably, the binder is bentonite, and the dosage of the binder is 2% of the mass of the high-iron bauxite powder.

[0018] Preferably, the addition amount of water is 8% - 10% of the mass of the high-iron bauxite powder.

[0019] Preferably, the method for separating and extracting Al2O3, Fe2O3, and SiO2 from the water-quenched slag is:

[0020] S1: Grind the water-quenched slag to a powder of about 80 μm, then dehydrate it to a water content of 10%, and add ammonium sulfate to mix and form pellets;

[0021] S2: Heat the pellets made in step S1 to 400°C - 500°C and roast for 1 hour; the chemical reactions that occur are:

[0022] Fe2O3 + 3(NH4)2SO4 = Fe2(SO4)3 + 6NH3 + 3H2O

[0023] FeO + (NH4)2SO4 = FeSO4 + 2NH3 + H2O

[0024] Al2O3 + 3(NH4)2SO4 = Al2(SO4)3 + 6NH3 + 3H2O

[0025] SiO2 in the slag does not participate in the reaction. The excessive (NH4)2SO4 decomposes to form NH3, SO3, and H2O.

[0026] (NH4)2SO4 = 2NH3↑ + SO3↑ + H2O↑

[0027] (NH4)2SO4 is generated again during the cooling process.

[0028] 2NH3 + SO3 + H2O = (NH4)2SO4

[0029] The NH3 generated in this step is recycled and used in the subsequent processes.

[0030] S3: Add water to leach the clinker produced by roasting. The liquid-solid mass ratio of water to the clinker is 3:1, and the leaching time is 1 hour. Filter and separate the leached product to obtain the filter residue SiO2 and filtrate A containing Al2(SO4)3, Fe2(SO4)3, FeSO4, and (NH4)2SO4.

[0031] S4: Add the reducing agent iron filings to filtrate A and react for 4 hours to reduce the trivalent iron in filtrate A to divalent iron. The chemical reaction is

[0032] Fe 3+ +Fe = Fe 2+

[0033] Remove the iron filings to obtain a solution.

[0034] S5: Add NH3 to the solution to adjust the pH value to 6, and the following chemical reaction occurs

[0035] Al2(SO4)3 + 6NH3 + 3H2O = 2Al(OH)3↓ + 3(NH4)2SO4

[0036] Al(OH)3 precipitate is generated. Filter to obtain solid Al(OH)3 and filtrate B.

[0037] S6: Add NH3 to filtrate B to adjust the pH value to 7, and the following chemical reaction occurs

[0038] FeSO4 + 2NH3 + 2H2O = Fe(OH)2↓ + (NH4)2SO4

[0039] Fe(OH)2 precipitate is generated. Filter to obtain solid Fe(OH)2 and filtrate C. Filtrate C mainly contains (NH4)2SO4. Heat the solid Fe(OH)2 in the air to 500°C, and the following chemical reaction occurs

[0040] 2Fe(OH)2 + 1 / 2O2 = Fe2O3 + 2H2O

[0041] Obtain Fe2O3 product;

[0042] S7: Add the solid Al(OH)3 obtained in step S5 into a NaOH solution with a concentration of 150 g / L, react for 1 hour at a temperature of 60 °C, and a chemical reaction occurs

[0043] Al(OH)3 + NaOH = NaAlO2 + 2H2O

[0044] Al(OH)3 dissolves to saturation, generating a sodium aluminate solution;

[0045] S8: After filtering and removing impurities from the sodium aluminate solution, add a small amount of Al(OH)3 as seeds to the solution to precipitate pure Al(OH)3,

[0046] Filter to obtain Al(OH)3 crystals and a mother liquor containing NaOH and NaAlO2. Calcinate the Al(OH)3 crystals at 1300 °C to obtain Al2O3 product, and return the mother liquor to step S7 for recycling;

[0047] S9: Evaporate and dehydrate the filtrate C to obtain ammonium sulfate crystals, and return them to step S1 for recycling;

[0048] Preferably, the preparation method for separating and extracting Al2O3, Fe2O3, and SiO2 from the slag after water quenching is as follows:

[0049] S1: Grind the slag after water quenching to about 80 μm, then dehydrate it to a moisture content of less than 1%, add a sulfuric acid solution with a concentration of 80% and mix evenly, and make pellets with a pellet size of 20 mm - 30 mm;

[0050] S2: Heat the pellets made in step S1 to 400 °C - 500 °C and roast for 1 hour; the chemical reactions that occur

[0051] Fe2O3 + 3H2SO4 = Fe2(SO4)3 + 3H2O

[0052] FeO + H2SO4 = FeSO4 + H2O

[0053] Al2O3 + 3H2SO4 = Al2(SO4)3 + 3H2O

[0054] TiO2 + H2SO4 = TiOSO4 + H2O

[0055] H2SO4 = H2O + SO3

[0056] SiO2 does not participate in the reaction, and the generated SO3 is absorbed with dilute sulfuric acid and returned to the batching;

[0057] S3: Dissolve the clinker produced by roasting in water. The liquid-solid mass ratio of water to the clinker is 3:1, and the dissolution time is 1 hour. Filter and separate the dissolved matter to obtain filter residue SiO2 and filtrate A containing Al2(SO4)3, Fe2(SO4)3, and FeSO4;

[0058] S4: Add Na2CO3 to filtrate A to adjust the pH value to 3, generating Fe(OH)3 precipitate, and the chemical reaction occurs as

[0059] Fe2(SO4)3 + 3Na2CO3 + 3H2O = 2Fe(OH)3↓ + 3Na2SO4 + 3CO2↑

[0060] Filter to obtain solid Fe(OH)3 and filtrate B. Heat Fe(OH)3 in the air to 600 °C, and the chemical reaction is 2Fe(OH)3 = Fe2O3 + 3H2O

[0061] Obtain Fe2O3 product;

[0062] S5: Add Na2CO3 to filtrate B to adjust the pH value to 6, generating Al(OH)3 precipitate, and the chemical reaction occurs as

[0063] Al2(SO4)3 + 3Na2CO3 + 3H2O = 2Al(OH)3↓ + 3Na2SO4 + 3CO2↑

[0064] Filter to obtain solid Al(OH)3 and filtrate C;

[0065] S6: Add Na2CO3 to filtrate C to adjust the pH value to 7, generating Fe(OH)2 precipitate, and the chemical reaction occurs as

[0066] FeSO4 + Na2CO3 + H2O = Fe(OH)2↓ + Na2SO4 + CO2↑

[0067] Filter to obtain solid Fe(OH)2 and filtrate D. Filtrate D is a solution containing Na2SO4,

[0068] Heat solid Fe(OH)2 in the air to 500 °C, and the chemical reaction occurs as

[0069] 2Fe(OH)2 + 1 / 2O2 = Fe2O3 + 2H2O

[0070] Obtain Fe2O3 product;

[0071] S7: Add the solid Al(OH)3 obtained in step S5 to a NaOH solution with a concentration of 150 g / L, react for 1 hour at a temperature of 60 °C, and the chemical reaction is

[0072] Al(OH)3 + NaOH = NaAlO2 + 2H2O

[0073] Al(OH)3 dissolves to saturation, and sodium aluminate solution is produced by reaction;

[0074] S8: After the sodium aluminate solution is finely filtered to remove impurities, a small amount of Al(OH)3 is added to the solution as crystal seeds to precipitate pure Al(OH)3,

[0075] filtered to obtain Al(OH)3 crystals and mother liquor of NaOH solution containing Al(OH)3. The Al(OH)3 crystals are calcined at 1300 °C to obtain Al2O3 products, and the mother liquor is returned to the process of step S7 for recycling;

[0076] S9: Add NH4HCO3 to filtrate D to form NaHCO3 precipitate and (NH4)2SO4 solution. The chemical reaction is

[0077] Na2SO4 + 2NH4HCO3 = (NH4)2SO4 + 2NaHCO3↓

[0078] filtered to obtain solid NaHCO3 and filtrate E. Filtrate E is a solution containing (NH4)2SO4. The filtrate E is dehydrated to obtain ammonium sulfate crystals.

[0079] Preferably, the mass ratio of the slag to ammonium sulfate is 1:2.

[0080] Preferably, the mass ratio of the slag to sulfuric acid is 1:1.5.

[0081] Preferably, the flue gas generated in the electric arc furnace is introduced into the combustion chamber and air is introduced to burn hydrogen in the combustion chamber. The heat of the flue gas and the heat generated by hydrogen combustion are used for power generation. Chemical reactions occur in the combustion chamber

[0082] 2H2 + O2 = 2H2O

[0083] Preferably, it further includes a dust recovery step. The dust generated by the reaction in the electric furnace is recovered through a dust removal system, and the recovered dust is returned to S1 for pelletizing.

[0084] Due to the adoption of the above technical solution, the present invention has the following beneficial effects:

[0085] The method for extracting iron from high-iron bauxite in the present invention reduces iron oxides in high-iron bauxite to metallic iron with hydrogen, does not produce CO2, and has no carbon pollution. The recovery rate of iron in the method reaches 95%, and the prepared iron meets the national standard YB / T5296 - 2011 of the ferrous metallurgy industry in the People's Republic of China.

[0086] After the iron is removed from the slag, the slag is water-quenched, crushed, and then separated to extract products of Al2O3, Fe2O3, and SiO2. The recovery rate of Al2O3 in the slag reaches 98%, and the recovery rate of SiO2 reaches 99%. The recovery rates of Fe2O3 and FeO reach 99%.

[0087] This method extracts iron from high-iron bauxite, and then extracts aluminum oxide, iron oxide, and silicon dioxide from the slag. There is almost no residue left. The process cost is low and the energy consumption is small. It is a method for comprehensively utilizing high-iron bauxite with low cost and high benefit. Brief Description of the Drawings

[0088] Figure 1 It is a process flow diagram for the comprehensive utilization of high-iron bauxite in the invention;

[0089] Figure 2 It is a process flow diagram for separating and extracting Al2O3, Fe2O 3、 SiO2 after the slag of Method 1 is water-quenched;

[0090] Figure 3 It is a process flow diagram for separating and extracting Al2O3, Fe2O 3、 SiO2 after the slag of Method 2 is water-quenched; Detailed Embodiments

[0091] The following further describes the detailed embodiments of the present invention in conjunction with the embodiments.

[0092] The composition of the high-iron bauxite used in the following embodiments is Fe2O3 46.18%, Al2O3 34.29%, SiO2 11.83%, CaO 0.83%, and others 6.87%.

[0093] Embodiment 1

[0094] A method for comprehensively utilizing high-iron bauxite includes the following steps:

[0095] (1) Grind the high-iron bauxite into powder ore of about 80μm, mix it evenly with bentonite and water to form pellets of 20mm - 30mm; the dosage of the binder is 2% of the mass of the high-iron bauxite powder, and the added amount of water is 8% of the mass of the high-iron bauxite powder;

[0096] (2) Dry the formed pellets at 200℃ until the water content is below 1%;

[0097] (3) Add the dried pellets to an electric arc furnace, heat to 1500℃ to melt, form a molten pool, and introduce hydrogen into the molten pool to generate molten iron and slag; when the molten iron and slag in the electric arc furnace reach a certain amount, first tap the slag and then tap the iron. Pour the slag into the slag ladle and the molten iron into the molten iron ladle; the hydrogen introduction amount is 100% in excess of the hydrogen amount required to completely reduce the iron oxides in the molten pool;

[0098] (4) Use the molten iron for steelmaking or casting;

[0099] (5) Quench the slag with water and grind it to about 80 μm, dehydrate it until the slag contains about 10% water, mix it evenly with ammonium sulfate, form pellets of 20 mm - 30 mm, and the mass ratio of slag to ammonium sulfate is 1:2;

[0100] (6) Heat the pellets made in step (5) to 400 °C and roast for 1 hour;

[0101] (7) Dissolve the roasted clinker in water, the liquid-solid mass ratio of water to clinker is 3:1, the dissolution time is 1 hour, filter and separate the dissolved matter to obtain filter residue SiO2 and filtrate A containing Al2(SO4)3, Fe2(SO4)3, FeSO4, and (NH4)2SO4;

[0102] (8) Add an excessive amount of 100% reducing agent iron filings to filtrate A, react for 4 hours, reduce the trivalent iron in filtrate A to divalent iron, remove the iron filings to obtain a solution;

[0103] (9) Add NH3 to the reduced solution, adjust the pH value to 6, generate Al(OH)3 precipitate, filter to obtain solid Al(OH)3 and filtrate B;

[0104] (10) Add NH3 to filtrate B, adjust the pH value to 7, generate Fe(OH)2 precipitate, filter to obtain solid Fe(OH)2 and filtrate C. Filtrate C mainly contains (NH4)2SO4. Heat the solid Fe(OH)2 in air to 500 °C to obtain Fe2O3 product;

[0105] (11) Add the solid Al(OH)3 obtained in step (9) to a NaOH solution with a concentration of 150 g / L, react for 1 hour at a temperature of 60 °C to dissolve Al(OH)3 to saturation, and react to generate a sodium aluminate solution;

[0106] (12) After filtering and removing impurities from the sodium aluminate solution, add a small amount of Al(OH)3 as crystal seeds to the solution, the crystal seed content is 0.2% of the solution mass, precipitate pure Al(OH)3, filter to obtain Al(OH)3 crystals and mother liquor containing NaOH and NaAlO2. Calcinate the Al(OH)3 crystals at 1300 °C to obtain Al2O3 product, and return the mother liquor to step (11) for recycling;

[0107] (13) Evaporate and dehydrate filtrate C to obtain ammonium sulfate crystals, and return them to step (5) for recycling;

[0108] (14) The flue gas generated in the electric arc furnace is introduced into the combustion chamber, and air is introduced into the combustion chamber to burn hydrogen in the combustion chamber. The heat of the flue gas and the heat generated by the combustion of hydrogen are used for power generation;

[0109] (15) The dust generated by the reaction in the electric furnace is recovered through the dust removal system, and the recovered dust is returned to step (1) for pelletizing.

[0110] In this method, the iron oxide in the high-iron bauxite is reduced to metallic iron by hydrogen, and the recovery rate of iron reaches 95%. The prepared iron meets the national black metallurgy industry standard YB / T5296-2011 of the People's Republic of China;

[0111] After the iron is extracted, the slag is water quenched and then separated and extracted to obtain Al2O3, Fe2O3 and SiO2 products. The recovery rate of Al2O3 in the slag reaches 98%, the recovery rate of SiO2 reaches 99%, and the recovery rates of Fe2O3 and FeO reach 99%.

[0112] Example 2

[0113] A method for comprehensively utilizing high-iron bauxite, comprising the following steps:

[0114] (1) Grind the high-iron bauxite into powder with a particle size of about 80μm, mix it evenly with bentonite and water to form pellets with a size of 20mm - 30mm; the dosage of the binder is 2% of the weight of the high-iron bauxite powder, and the addition amount of water is 10% of the weight of the high-iron bauxite powder;

[0115] (2) Dry the pellets made in step (1) at 300°C until the water content is less than 1%;

[0116] (3) Add the dried pellets in step (2) to the electric arc furnace, heat to 1600°C to melt, form a molten pool, and introduce hydrogen into the molten pool to generate molten iron and slag; when the molten iron and slag in the electric arc furnace reach a certain amount, first tap the slag and then tap the iron. The slag is poured into the slag ladle, and the molten iron is poured into the molten iron ladle; the addition amount of hydrogen is 100% more than the amount of hydrogen required to completely reduce the iron oxide in the molten pool;

[0117] (4) Use the molten iron for steelmaking or casting;

[0118] (5) Water quench the slag and grind it to about 80μm, then dehydrate it to a water content of less than 1%, add a sulfuric acid solution with a concentration of 80% and mix to form pellets. The particle size of the pellets is 20mm - 30mm, and the mass ratio of the slag to the sulfuric acid is 1:1.5;

[0119] (6) Heat the pellets made in step (5) to 500°C and roast for 1 hour;

[0120] (7) The clinker produced by roasting is leached with water. The liquid-solid mass ratio of water to clinker is 3:1, and the leaching time is 1 hour. The leached product is filtered and separated to obtain filter residue SiO2 and filtrate A containing Al2(SO4)3, Fe2(SO4)3 and FeSO4;

[0121] (8) Na2CO3 is added to filtrate A to adjust the pH value to 3, generating Fe(OH)3 precipitate. After filtration, solid Fe(OH)3 and filtrate B are obtained. The solid Fe(OH)3 is heated in air to 600 °C to obtain Fe2O3 product;

[0122] (9) Na2CO3 is added to filtrate B to adjust the pH value to 6, generating Al(OH)3 precipitate. After filtration, solid Al(OH)3 and filtrate C are obtained;

[0123] (10) Na2CO3 is added to filtrate C to adjust the pH value to 7, generating Fe(OH)2 precipitate. After filtration, solid Fe(OH)2 and filtrate D are obtained. Filtrate D is a solution containing sodium sulfate. The solid Fe(OH)2 is heated in air to 500 °C to obtain Fe2O3 product;

[0124] (11) The solid Al(OH)3 obtained in step (9) is added to a NaOH solution with a concentration of 150 g / L, and the reaction is carried out for 1 hour at a temperature of 60 °C to dissolve Al(OH)3 to saturation, generating a sodium aluminate solution;

[0125] (12) After the sodium aluminate solution is finely filtered to remove impurities, a small amount of Al(OH)3 is added to the solution as seeds to precipitate pure Al(OH)3. After filtration, Al(OH)3 crystals and mother liquor containing NaOH and NaAlO2 are obtained. The Al(OH)3 crystals are calcined at 1300 °C to obtain Al2O3 product, and the mother liquor is returned to the process of step (11) for recycling;

[0126] (13) NH4HCO3 is added to filtrate D to generate NaHCO3 precipitate and (NH4)2SO4 solution. After filtration, solid NaHCO3 and filtrate E are obtained. Filtrate E is evaporated to obtain ammonium sulfate crystals;

[0127] (14) The flue gas generated in the electric arc furnace is introduced into the combustion chamber during combustion, and air is introduced into the combustion chamber to burn hydrogen in the combustion chamber. The heat of the flue gas and the heat generated by hydrogen combustion are used for power generation;

[0128] (15) The dust generated by the reaction in the electric furnace is recovered through the dust removal system, and the recovered dust is returned to step (1) for pelletizing.

[0129] This method reduces iron oxides in high-iron bauxite to metallic iron with hydrogen, and the recovery rate of iron reaches 95%. The prepared iron meets the China National Standard for the Black Metallurgy Industry YB / T5296-2011.

[0130] After the iron extraction, the slag is quenched with water and then separated and extracted to obtain products of Al2O3, TiO2, Fe2O3 and SiO2. The recovery rate of Al2O3 in the slag reaches 98%, the recovery rate of SiO2 reaches 99%, and the recovery rates of Fe2O3 and FeO reach 99%.

[0131] The above description is a detailed description of the preferred and feasible embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. Any equivalent changes or modifications made under the guidance of the present invention shall fall within the scope of the patent covered by the present invention.

Claims

1. A method for comprehensively utilizing high-iron bauxite, characterized in that It includes the following steps: (1) Grind the high-iron bauxite into fine powder ore, mix it evenly with a binder and water to form pellets. If using lump ore of 20mm - 30mm, there is no need to form pellets and it can be directly added to the electric arc furnace; (2) Dry the formed pellets at 200°C - 300°C until the water content is less than 1%; (3) Add the dried pellets to the electric arc furnace, heat to 1500°C - 1600°C to melt, form a molten pool, introduce hydrogen into the molten pool to generate molten iron and slag. The hydrogen addition amount is 100% in excess of the hydrogen amount required to completely reduce iron oxides in the molten pool; (4) Use the molten iron for steelmaking or casting, and use the water-quenched slag to separate and extract Al2O3, Fe2O3 and SiO2.

2. The method for comprehensively utilizing high-iron bauxite according to claim 1, wherein In step (1), the fine powder ore is ground to a powder of about 80μm, and is mixed evenly with a binder and water to form pellets of 20mm - 30mm.

3. A method for comprehensively utilizing high-iron bauxite according to claim 1, characterized in that, The binder is bentonite, and the dosage of the binder is 2% of the mass of the high-iron bauxite powder.

4. A method for comprehensively utilizing high-iron bauxite according to claim 1, characterized in that, The addition amount of water is 8% - 10% of the mass of the high-iron bauxite powder.

5. A method for comprehensively utilizing high-iron bauxite according to claim 1, characterized in that, The preparation method for separating and extracting Al2O3, Fe2O3 and SiO2 from the water-quenched slag is as follows: S1: Grind the water-quenched slag to about 80μm, dehydrate to 10% water content of the slag, mix it evenly with ammonium sulfate, and form pellets of 20mm - 30mm; S2: Heat the pellets made in step S1 to 400°C - 500°C, roast for 1 hour, and recover the generated NH3 and SO3; S3: Add water to dissolve the roasted clinker, the liquid-solid mass ratio of water to clinker is 3:1, the dissolution time is 1 hour, filter and separate the dissolved matter to obtain filter residue SiO2 and filtrate A containing Al2(SO4)3, Fe2(SO4)3, FeSO4 and (NH4)2SO4; S4: Add reducing agent iron filings to filtrate A, react for 4 hours, reduce the trivalent iron in the filtrate to divalent iron, remove the iron filings, and obtain a solution; S5: Pass ammonia gas into the solution, adjust the PH value to 6, generate Al(OH)3 precipitate, filter to obtain solid Al(OH)3 and filtrate B; S6: Pass ammonia gas into filtrate B, adjust the PH value to 7, generate Fe(OH)2 precipitate, filter to obtain solid Fe(OH)2 and filtrate C. Filtrate C is a solution containing ammonium sulfate. Heat solid Fe(OH)2 in the air to 500°C to obtain Fe2O3 product; S7: Add the solid Al(OH)3 obtained in step S5 to a NaOH solution with a concentration of 150g / L, react for 1 hour at a temperature of 60°C to dissolve Al(OH)3 to saturation and generate a sodium aluminate solution; S8: After finely filtering and removing impurities from the sodium aluminate solution, add a small amount of Al(OH)3 as seed crystals to the solution, precipitate pure Al(OH)3, filter to obtain Al(OH)3 crystals and mother liquor containing NaOH and NaAlO2. Calcinate the Al(OH)3 crystals at 1300°C to obtain Al2O3 product, and return the mother liquor to step S7 for recycling; S9: Evaporate and dehydrate filtrate C to obtain ammonium sulfate crystals, and return them to step S1 for recycling.

6. A method for comprehensively utilizing high-iron bauxite according to claim 1, characterized in that, The preparation method for separating and extracting Al2O3, Fe2O3, and SiO2 from the granulated slag by quenching is as follows: S1: Grind the granulated slag by quenching to a powder of about 80 μm, then dehydrate it to a water content of less than 1%, and add a sulfuric acid solution with a concentration of 80% to mix and pelletize; S2: Heat the pellets made in step S1 to 400 °C - 500 °C, roast for 1 hour, and recover the excessive SO3; S3: Dissolve the clinker produced by roasting in water, with the liquid-solid mass ratio of water to clinker being 3:1 and the dissolution time being 1 hour. Filter and separate the dissolved matter to obtain the filter residue SiO2 and the filtrate A containing Al2(SO4)3, Fe2(SO4)3, and FeSO4; S4: Add Na2CO3 to the filtrate A, adjust the pH value to 3 to produce Fe(OH)3 precipitation, filter to obtain the solid Fe(OH)3 and the filtrate B. Calcinate the solid Fe(OH)3 in the air at 600 °C to obtain the Fe2O3 product; S5: Add Na2CO3 to the filtrate B, adjust the pH value to 6 to produce Al(OH)3 precipitation, filter to obtain the solid Al(OH)3 and the filtrate C; S6: Add Na2CO3 to the filtrate C, adjust the pH value to 7 to produce Fe(OH)2 precipitation, filter to obtain the solid Fe(OH)2 and the filtrate D. The filtrate D is a solution containing sodium sulfate. Calcinate the solid Fe(OH)2 in the air at 500 °C to obtain the Fe2O3 product; S7: Add the solid Al(OH)3 obtained in step S5 to a NaOH solution with a concentration of 150 g / L, react for 1 hour at a temperature of 60 °C to dissolve Al(OH)3 to saturation, and react to form a sodium aluminate solution; S8: After precisely filtering and removing impurities from the sodium aluminate solution, add a small amount of Al(OH)3 as seeds to the solution to precipitate pure Al(OH)3, filter to obtain Al(OH)3 crystals and the mother liquor. Calcinate the Al(OH)3 crystals at 1300 °C to obtain the Al2O3 product, and return the mother liquor to the process of step S7 for recycling; S9: The filtrate D is a sodium sulfate solution. Add NH4HCO3 to the filtrate to react to form NaHCO3 precipitation and a solution containing ammonium sulfate. Filter to obtain the NaHCO3 product and the solution containing (NH4)2SO4, and evaporate the solution to obtain ammonium sulfate crystals; 7. A method for comprehensively utilizing high-iron bauxite according to claim 5, characterized in that, The mass ratio of the granulated slag to ammonium sulfate is 1:

2.

8. A method for comprehensively utilizing high-iron bauxite according to claim 6, characterized in that, The mass ratio of the granulated slag to sulfuric acid is 1:1.

5.

9. A method for comprehensively utilizing high-iron bauxite according to claim 1, characterized in that, The flue gas generated in the electric arc furnace is introduced into the combustion chamber, and air is introduced to burn hydrogen in the combustion chamber. The heat generated by hydrogen combustion and the heat of the flue gas are used for power generation; 10. A method for comprehensively utilizing high-iron bauxite according to claim 1, characterized in that, It also includes a dust recovery step. The dust generated by the reaction in the electric furnace is recovered by the dust removal system and returned to (1) pelletizing.

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