A process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas

Abstract

The present invention provides a process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas, belonging to the field of environmental protection technology. The present invention uses the residual carbon in the gasification slag as a catalyst, and realizes the gasification slag chemical method to extract aluminum and silicon under the action of the polyacid aqua regia effect and electrochemical action. The present invention adopts a heap retting neutralization method to convert the super acid and the aluminum and iron oxides in the ash into soluble salts, and sequentially replaces the iron hydroxide, aluminum hydroxide and polyacid ammonium from the salt solution through the ammonia replacement method, thereby overcoming the safety risks of the strong oxidizing property of the polyacid; utilizes the common ion effect to promote the rapid crystallization of the aluminum salt solution in the form of aluminum chloride; generates sodium silicate by the heap retting neutralization reaction of the slag and sodium hydroxide, and then introduces carbon dioxide to obtain silicic acid and sodium carbonate, and the sodium carbonate solution reacts with calcium hydroxide to obtain sodium hydroxide. Sodium hydroxide, polyacid, ammonia and activated carbon are recycled for the treatment of fly ash and coal gangue, realizing the comprehensive utilization of polyacid solid waste.

Description

Technical Field

[0001] The present invention relates to the field of environmental protection technology, and in particular to a process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas. Background Art

[0002] The management and utilization of bulk industrial solid waste includes the comprehensive utilization of major wastes such as fly ash from coal combustion, gasification slag from coal chemical processing, and gangue from coal mining. my country's coal-fired power plants generate over 800 million tons of fly ash annually, with cumulative stockpiles exceeding 3 billion tons. Deep coal chemical processing generates over 70 million tons of gasification slag annually, with cumulative stockpiles exceeding 300 million tons. The annual generation of gangue, a byproduct of coal mining, exceeds 800 million tons, with cumulative stockpiles exceeding 5 billion tons. The large-scale storage of these wastes not only occupies land resources but, in the absence of effective management, can also cause varying degrees of pollution to the atmosphere, soil, and groundwater. Currently, conventional management measures mostly rely on separate treatment methods. The treatment of gasification slag primarily involves extracting residual carbon. This waste is then used in various fields, including building materials, road construction, backfill projects, and agriculture, with a utilization rate of less than 50%. Due to the large amount of fly ash produced, some is used in the building materials industry, with the majority destined for landfill. While a small portion of coal gangue is used for waste heat recovery through incineration, the majority is backfilled in mines or buried underground. In the building materials industry, fly ash and aerated slag are primarily used in the production of cement, commercial concrete, and new wall materials such as fly ash bricks, aerated slag bricks, and aerated concrete products. In road construction, fly ash and aerated slag are primarily used as roadbed and as an admixture for road pavement concrete. These methods result in low fly ash and aerated slag utilization, uncertain product quality, and low added value. In agriculture, gasification slag is mainly used for soil improvement and nutrient fertilizer. Due to the complex composition of gasification slag, in addition to trace available nutrients, it also contains a large amount of harmful metal elements and heavy metal elements. Plants absorb beneficial nutrients while also absorbing harmful metal elements. On the one hand, they remain in the plant body and fruit, which is harmful to human health. On the other hand, they will leak underground and pollute the soil and groundwater. Therefore, these components will pose great uncertainties to human health and soil safety, and secondary pollution is serious. Therefore, high-value comprehensive utilization technologies for bulk industrial wastes such as fly ash, gasification slag, and coal gangue still need to be developed and expanded.

[0003] Carbon dioxide is an inevitable product of industrial development. In recent years, due to the accelerated pace of global industrialization, carbon dioxide emissions have become a major hidden danger threatening human survival and development. Climate warming, declining ecological carrying capacity, atmospheric circulation imbalance, and a surge in extreme weather events all indicate that the accumulation of carbon dioxide in the atmosphere has reached a critical point. Carbon dioxide emissions have become a major threat to human survival. Therefore, the reduction, capture and recovery of carbon dioxide in industrial production are key factors and important thresholds restricting future industrial development. The technology of carbon dioxide capture, recovery and utilization will become the most concerned topic in the sustainable development of industrialization. Summary of the Invention

[0004] The purpose of the present invention is to provide a process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas to solve the above-mentioned technical problems.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas, comprising the following steps:

[0007] Step 1): Fumed slag, hydrochloric acid solution, sulfuric acid solution and nitric acid solution are sequentially mixed to obtain slurry 1, and then a catalyst promoter is mixed with slurry 1 to obtain slurry 2. Thereafter, the slurry is subjected to composting and neutralization, washing and dissolving, and filter press separation in sequence to obtain slag 1 and mixed solution 1;

[0008] The mixed solution 1 is a mixed solution containing aluminate and ferrite;

[0009] Step 2): using an ammonia replacement method to replace the iron hydroxide and heavy metal hydroxide in the mixed solution 1, raising the pH value to replace the aluminum hydroxide precipitate and the polyacid ammonium solution, and heat-treating the aluminum hydroxide precipitate to produce the finished alumina product, or neutralizing it with hydrochloric acid to produce the finished aluminum chloride product;

[0010] Step 3): Pyrolyzing the obtained polyacid ammonium solution to obtain ammonia gas and polyacid residual liquid, wherein the ammonia gas is reused in the ammonia replacement method in step 2), and the polyacid residual liquid is reused in the preparation of slurry 1;

[0011] Step 4): The obtained slag material 1 is subjected to a first alkali dissolution, followed by dissolution with clean water and separation by filter pressing to obtain a mixed solution 2 and slag material 2;

[0012] The mixed solution 2 is a mixed solution containing sodium silicate and sodium tetrahydroxyaluminate;

[0013] Step 5): The obtained slag 2 is subjected to a second alkali dissolution, followed by water dissolution and filter press separation to obtain a mixed solution 3 and slag 3. The slag 3 is dried and activated to produce activated carbon, which is then mixed with fly ash and / or coal gangue powder as a catalyst and reused in step 1);

[0014] The mixed solution 3 is a mixed solution containing sodium silicate;

[0015] Step 6): the mixed solution 2 reacts by absorbing carbon dioxide produced in the process tail gas, and is filtered to obtain solid 1 and sodium carbonate solution;

[0016] Solid 1 is a mixture of silicic acid and aluminum hydroxide;

[0017] Step 7): the mixed solution 3 reacts by absorbing carbon dioxide produced in the process tail gas, and is filtered to obtain a silicic acid and sodium carbonate solution;

[0018] Step 8): combining the sodium carbonate solutions obtained in step 6) and step 7), adding calcium hydroxide to carry out a causticization reaction to obtain a sodium hydroxide solution and calcium carbonate. The sodium hydroxide solution can be recycled, and the calcium carbonate is dried to obtain a finished product.

[0019] Step 9): The silicic acid obtained in step 7) is subjected to hydrothermal synthesis and then dried to prepare a silicon dioxide product; the mixture of silicic acid obtained in step 6) and aluminum hydroxide is mixed with the heavy metal hydroxide obtained in step 2) to prepare a high-aluminum molecular sieve.

[0020] In step 1), the main components of the gasified slag include aluminum oxide and iron oxide;

[0021] According to the content of aluminum oxide and iron oxide in the gasified slag, the amount of the acid is calculated and prepared according to the percentage of the relative molecular mass of various acids consumed in converting aluminum oxide and iron oxide according to the chemical reaction formula;

[0022] The mass concentration of the hydrochloric acid solution is 35-37%, the mass concentration of the sulfuric acid solution is 50-98%, and the mass concentration of the nitric acid solution is 50-98%. The ratio of the hydrochloric acid solution, the sulfuric acid solution, and the nitric acid solution is 5-15%:5-15%:70-90%;

[0023] The catalytic effect of the carbon residue surface activity refers to the fact that the abundant active sites on the carbon residue surface have the ability to accept and donate electrons, and can produce electrochemical reactions.

[0024] Furthermore, in step 1), the catalyst promoter comprises an oxygen-containing acid solution of hydrogen peroxide and / or chlorine, the volume concentration of the hydrogen peroxide solution is 27.5-40%, the concentration of the oxygen-containing acid solution of chlorine is 25-30%, and the oxygen-containing acid of chlorine in the oxygen-containing acid solution of chlorine comprises one or more of HClO4, HClO3, HClO2 and HClO;

[0025] The total amount of the hydrogen peroxide solution and the chlorine-containing oxygen acid solution accounts for 5-10% of the total mass of the hydrochloric acid solution, the sulfuric acid solution and the nitric acid solution.

[0026] Furthermore, in step 1), the temperature of the retting and neutralization is 50 to 80° C., and the time of the retting and neutralization is 8 to 12 hours;

[0027] The washing solution is clean water washing solution, and the water-to-material ratio is 3-5:1.

[0028] Furthermore, in step 2), the ammonia replacement method includes adding ammonia water or introducing ammonia gas.

[0029] Furthermore, in step 2), the aluminum hydroxide precipitate is heat-treated to obtain a finished alumina product, and when the heat treatment temperature is 140-150° C., γ-type alumina is obtained;

[0030] When the heat treatment temperature is 900℃~1200℃, α-type alumina is obtained;

[0031] The concentration of the hydrochloric acid solution in the hydrochloric acid neutralization reaction is ≥25wt%;

[0032] The hydrochloric acid neutralization reaction is to rapidly crystallize the aluminum chloride solution to precipitate aluminum chloride crystals through the common ion effect. The crystals are aluminum chloride hexahydrate, and the mass concentration of the added hydrochloric acid is greater than 30%.

[0033] Furthermore, in step 4), the reagent used for the first alkaline dissolution is sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is 20-42%.

[0034] Furthermore, in step 5), the reagent used for the second alkaline dissolution is sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is 30-42%.

[0035] Furthermore, in step 5), the volume ratio of the fly ash and / or coal gangue powder to the activated carbon is 1:0.2-0.5.

[0036] Beneficial effects of the present invention:

[0037] The process for the coordinated treatment and resource utilization of industrial waste gasification slag, fly ash, coal gangue, and carbon dioxide in waste gas implemented by the present invention not only realizes the resource utilization of gasification slag, fly ash, and coal gangue through chemical treatment to extract aluminum, extract silicon, and remove carbon, but also produces a synergistic effect in the resource utilization, turning pollutants into benefits and generating huge added value. The following objectives can be achieved:

[0038] 1) Through the aqua regia effect of polyacids in chemical reactions, the reaction activity of reactants is improved;

[0039] 2) Transforming the carbon residue from gasification slag into a catalyst that can promote the extraction of aluminum and silicon from fly ash and coal gangue, providing an electrochemical reaction carrier for the aluminum and silicon extraction reactions and enhancing the efficacy of the chemical reactions;

[0040] 3) Using H2O2, HClO4, HClO3, HClO2, and HClO as catalyst promoters to enhance the reactivity of the oxidant while helping the catalyst to produce electrochemical effects, thereby improving the oxidation performance of the oxidant;

[0041] 4) By absorbing carbon dioxide through the product sodium silicate, a cheap ion exchange medium is obtained while recovering carbon dioxide in the process, so that the overall process achieves a synergistic effect;

[0042] 5) By adopting the retting neutralization process, the corrosion of reaction equipment and operational safety risks caused by the strong oxidizing and corrosive properties of polyacids are overcome, and the conventional dynamic chemical reaction mode is changed to a static reaction mode, which simplifies the process flow, shortens the production line, and reduces operating costs and safety risks;

[0043] 6) The heavy metal elements in the solid waste are extracted by acid dissolution and mixed with high-aluminum molecular sieve for solidification, which not only realizes the full utilization of solid waste materials, but also makes the hazardous waste elements play a greater value in the adsorption material. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a flow chart of the process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas according to the present invention. DETAILED DESCRIPTION

[0045] The present invention provides a process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas, comprising the following steps:

[0046] Step 1): Fumed slag, hydrochloric acid solution, sulfuric acid solution, and nitric acid solution are sequentially mixed to obtain slurry 1, and a catalyst promoter is then mixed with slurry 1 to obtain slurry 2. The chemical reaction is then enhanced under the catalytic effect of the surface activity of the residual carbon and the assistance of the promoter, and retting, neutralization, washing, and filter press separation are sequentially performed to obtain slag 1 and mixed solution 1.

[0047] The mixed solution 1 is a mixed solution containing aluminate and ferrite;

[0048] Step 2): using an ammonia replacement method to replace the iron hydroxide and heavy metal hydroxide in the mixed solution 1, raising the pH value to replace the aluminum hydroxide precipitate and the polyacid ammonium solution, and heat-treating the aluminum hydroxide precipitate to produce the finished alumina product, or neutralizing it with hydrochloric acid to produce the finished aluminum chloride product;

[0049] Step 3): Pyrolyzing the obtained polyacid ammonium solution to obtain ammonia gas and polyacid residual liquid, wherein the ammonia gas is reused in the ammonia replacement method in step 2), and the polyacid residual liquid is reused in the preparation of slurry 1;

[0050] Step 4): The obtained slag material 1 is subjected to a first alkali dissolution, followed by dissolution with clean water and separation by filter pressing to obtain a mixed solution 2 and slag material 2;

[0051] The mixed solution 2 is a mixed solution containing sodium silicate and sodium tetrahydroxyaluminate;

[0052] Step 5): The obtained slag 2 is subjected to a second alkali dissolution, followed by water dissolution and filter press separation to obtain a mixed solution 3 and slag 3. The slag 3 is dried and activated to produce activated carbon, which is then mixed with fly ash and / or coal gangue powder as a catalyst and reused in step 1);

[0053] The mixed solution 3 is a mixed solution containing sodium silicate;

[0054] Step 6): the mixed solution 2 reacts by absorbing carbon dioxide produced in the process tail gas, and is filtered to obtain solid 1 and sodium carbonate solution;

[0055] Solid 1 is a mixture of silicic acid and aluminum hydroxide;

[0056] Step 7): the mixed solution 3 reacts by absorbing carbon dioxide produced in the process tail gas, and is filtered to obtain a silicic acid and sodium carbonate solution;

[0057] Step 8): combining the sodium carbonate solutions obtained in step 6) and step 7), adding calcium hydroxide to carry out a causticization reaction to obtain a sodium hydroxide solution and calcium carbonate. The sodium hydroxide solution can be recycled, and the calcium carbonate is dried to obtain a finished product.

[0058] Step 9): The silicic acid obtained in step 7) is subjected to hydrothermal synthesis and then dried to prepare a silicon dioxide product; the mixture of silicic acid obtained in step 6) and aluminum hydroxide is mixed with the heavy metal hydroxide obtained in step 2) to prepare a high-aluminum molecular sieve.

[0059] In the present invention, in step 1), hydrochloric acid solution is first injected into the gasified slag, stirred and mixed, and then sulfuric acid solution and nitric acid solution are injected in sequence, so that the three acids are fully mixed with the gasified slag under stirring to form a semi-fluid thick slurry, i.e., slurry 1.

[0060] In the present invention, in step 1), the retting is a method of introducing a heat source to heat and then leaving the retting to neutralize the reaction. The material and the solvent are mixed into a paste-like semi-fluid slurry, and the mixture is then retting in a sealed container in a static state.

[0061] During the composting process, the super acid reacts with the aluminum oxide and iron oxide in the ash to form soluble aluminates and ferrites during the static reaction, namely: 3H2SO4+Al2O3=Al2(SO4)3+3H2O;

[0062] 6HNO3+Al2O3=2Al(NO3)3+3H2O; 6HCl+Al2O3=2AlCl3+3H2O;

[0063] 3H2SO4+Fe2O3=Fe2(SO4)3+3H2O;

[0064] 6HNO3+Fe2O3=2Fe(NO3)3+3H2O;

[0065] 6HCl+Fe2O3=2FeCl3+3H2O.

[0066] In the present invention, in step 1), the material is allowed to rest for a set time and then discharged to a washing and dissolving vessel, where it is washed and dissolved with clean water to obtain the reaction products, aluminate solution and ferrite solution.

[0067] In the present invention, in step 1), the mixed solution of slag, aluminate and ferrite obtained after washing with clean water is filtered by plate and frame filter pressing to separate the aluminate and ferrite solution from the slag, i.e., slag 1 and mixed solution 1.

[0068] In the present invention, the aluminate and ferrite solutions can be separated from the slag by centrifugal dehydration or reverse osmosis membrane dehydration.

[0069] In the present invention, in step 2), the ammonia replacement method is to first adjust the pH value of the mixed solution 1 to ≤5, first replace the iron hydroxide and heavy metal hydroxide, and then increase the pH to a range of 5 to 9 to replace the aluminum hydroxide and polybasic ammonium hydroxide, that is:

[0070] Al2(SO4)3+6NH3H2O=2Al(OH)3+3(NH4)2SO4;

[0071] Fe2(SO4)3+6NH3H2O=2Fe(OH)3+3(NH4)2SO4;

[0072] Al(NO3)3+3NH3H2O=Al(OH)3+3NH4NO3;

[0073] Fe(NO3)3+3NH3H2O=Fe(OH)3+3NH4NO3;

[0074] AlCl3+3NH3H2O=Al(OH)3+3NH4Cl;

[0075] FeCl3+3NH3H2O=Fe(OH)3+3NH4Cl.

[0076] In the present invention, the heavy metal hydroxide includes hydroxides such as mercury and nickel.

[0077] In the present invention, in step 2), the hydrochloric acid is neutralized to produce the finished aluminum chloride product, and a hydrochloric acid solution with a mass fraction of preferably 15-25% is added to the aluminum hydroxide precipitate to react and convert it into aluminum chloride, that is, Al(OH)3+3HCl=AlCl3+3H2O, and then hydrochloric acid with a mass fraction of preferably 30-35% is added to the aluminum chloride solution to produce a common ion effect, thereby promoting the rapid crystallization and precipitation of aluminum chloride.

[0078] In the present invention, in step 4), the first alkali dissolution reaction is:

[0079] SiO2+2NaOH=Na2SiO3+H2O;

[0080] Al2O3+2NaOH+3H2O=2NaAl(OH)4.

[0081] In the present invention, in step 5), the second alkali dissolution reaction is:

[0082] SiO2+2NaOH=Na2SiO3+H2O.

[0083] In the present invention, in step 5), the activated carbon is mixed with fly ash and / or coal gangue powder as a catalyst and reused in step 1), and treated by a heap retting neutralization method or a ramming neutralization method to dissolve aluminum and iron components to generate aluminates and ferrites, which are then washed, replaced, solid-liquid separated, and alkaline dissolved silica to achieve comprehensive utilization of fly ash and coal gangue powder.

[0084] In the present invention, in step 6), the absorption of carbon dioxide is carried out in a recoil-type casing bubbling absorber, and the reaction is: Na2SiO3+CO2+H2O=H2SiO3+Na2CO3.

[0085] In the present invention, in step 7), the absorption of carbon dioxide is carried out in a recoil-type casing bubble absorber, and the reaction is: 2NaAl(OH)4+CO2=2Al(OH)3+Na2CO3+H2O;

[0086] Na2SiO3+CO2+H2O=H2SiO3+Na2CO3.

[0087] In the present invention, in step 9), the silicic acid is hydrothermally synthesized to obtain metasilicic acid, which is then dried to produce a silicon dioxide product, i.e., H2SiO3→SiO2+H2O.

[0088] In the present invention, in step 9), the causticizing reaction is:

[0089] Na2CO3+Ca(OH)2=2NaOH+CaCO3.

[0090] In the present invention, the high-aluminum molecular sieve is a molecular sieve whose aluminum hydroxide content is greater than that of silicon dioxide and whose particle diameter is preferably between 0.4 nm and 1 nm.

[0091] In the present invention, in step 1), the main components of the gasified slag include aluminum oxide and iron oxide;

[0092] According to the content of aluminum oxide and iron oxide in the gasified slag, the amount of the acid is calculated and prepared according to the percentage of the mass of each acid consumed in converting aluminum oxide and iron oxide according to the chemical reaction formula;

[0093] The mass concentration of the hydrochloric acid solution is preferably 35-37%; the mass concentration of the sulfuric acid solution is preferably 50-98%; the mass concentration of the nitric acid solution is preferably 50-98%; the ratio of the hydrochloric acid solution, the sulfuric acid solution and the nitric acid solution is 5-15%:5-15%:70-90%, preferably 8-12%:8-12%:75-85%, and more preferably 10%:10%:80%.

[0094] In the present invention, the catalytic effect of the surface activity of the carbon residue refers to the fact that the abundant active sites on the surface of the carbon residue have the ability to accept and donate electrons, and can produce electrochemical reactions.

[0095] In the present invention, the hydrochloric acid solution, the sulfuric acid solution and the nitric acid solution are added in the order of acidity from strong to weak.

[0096] In the present invention, in step 1), the catalyst promoter comprises hydrogen peroxide solution and / or chlorine-containing acid solution, preferably hydrogen peroxide solution and chlorine-containing acid solution.

[0097] In the present invention, the mass concentration of the hydrogen peroxide solution is 27.5-40%, preferably 32-38%, and more preferably 35%; the concentration of the chlorine-containing acid solution is 25-30%, preferably 28%; the chlorine-containing acid in the chlorine-containing acid solution includes one or more of HClO4, HClO3, HClO2 and HClO, preferably HClO4, HClO3, HClO2 and HClO;

[0098] The total amount of the hydrogen peroxide solution and the chlorine-containing oxygen acid solution accounts for 5-10% of the total mass of the hydrochloric acid solution, the sulfuric acid solution and the nitric acid solution, preferably 8%.

[0099] In the present invention, in step 1), the temperature of the retting and neutralization is 50 to 80° C., preferably 70° C.; the time of the retting and neutralization is 8 to 12 hours, preferably 10 hours;

[0100] The washing solution is clean water washing solution, and the water-to-material ratio is 3 to 5:1, preferably 4:1.

[0101] In the present invention, in step 2), the ammonia replacement method includes adding ammonia water or passing ammonia gas, preferably passing ammonia gas.

[0102] In the present invention, in step 2), the aluminum hydroxide precipitation is heat-treated to produce alumina products. When the heat treatment temperature is 140-150°C, γ-type alumina is obtained. The heat treatment temperature is preferably 145°C.

[0103] When the heat treatment temperature is 900°C to 1200°C, α-type alumina is obtained, and the heat treatment temperature is preferably 1100°C;

[0104] The concentration of the hydrochloric acid solution in the hydrochloric acid neutralization reaction is ≥25 wt %, preferably 25 wt %.

[0105] In the present invention, in step 4), the reagent used for the first alkaline dissolution is sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is preferably 20-42%.

[0106] In the present invention, in step 5), the reagent used for the second alkaline dissolution is sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is preferably 30-42%.

[0107] In the present invention, in step 5), the volume ratio of the fly ash and / or coal gangue powder to the activated carbon is 1:0.2-0.5, more preferably 1:0.3.

[0108] In the present invention, gasified slag is formed under a multi-condition and multi-environment atmosphere. In the reaction atmosphere of a fixed-bed furnace, when the gasification temperature is below 1100°C, the silicate components in the coal ash cannot be completely decomposed, making the extraction of metal components difficult. In the reaction atmosphere of a pneumatic fluidized bed furnace, when the gasification temperature is above 1450°C, the aluminum oxide and silicon dioxide in the ash are sintered into mullite (3Al2O3+2SiO2) with strong chemical stability under this environment, becoming insoluble components that restrict the separation and purification of the ash. Regardless of whether there are silicate or mullite phase components in the ash, because they have stable chemical structures and are not easily oxidized by ordinary oxidants, they require a special oxidant to treat them for the purpose of comprehensive utilization. The method adopted by the present invention is to dissolve the ash with a polyacid to decompose the silicate and mullite therein into aluminum oxide, iron oxide, and silicon dioxide, and then convert and extract them through acid dissolution and alkali dissolution.

[0109] In the present invention, because the three acids react strongly when mixed simultaneously, they need to be mixed in order of acidity, starting with weak and then becoming strong, to form a super-strong oxidizing atmosphere in an atmosphere fully mixed with gasified slag. Sulfuric acid, nitric acid, and hydrochloric acid combine to form a composite acid with super-strong oxidizing and corrosive properties. When mixed with ash, the electrochemical action generated by the active sites on the surface of the ash carbon residue rapidly interrupts the silicon-aluminum and silicon-iron bonds in the silicate components, destroying their chemical structures. At the same time, the high concentration of hydrogen ions in the polyacid can form stable complex particles with oxygen ions on the surfaces of aluminum oxide and iron oxide, thereby reducing the potential of the metal ions and enhancing the reducing power of the metal particles, which is conducive to the reaction proceeding in the direction of metal dissolution. In this reaction process, the aqua regia effect generated by the polyacid enhances the chemical potential energy of aluminum dissolution and iron dissolution, improving the dissolution efficiency.

[0110] In the present invention, coal particles are rapidly cracked under high temperature conditions during the gasification reaction. This thermal cracking not only volatilizes volatile substances, but also gasifies most of the carbon elements into carbon monoxide in an atmosphere where the carbon reaches a reduced state. The remaining carbon residue relaxes its structural chains due to the high temperature and destroys the chemical bonds of the ash components, resulting in the rupture of the silicon-aluminum covalent bonds and silicon-iron covalent bonds in the ash. The aluminum, iron and silicon impurities in the carbon residue are extracted and dissolved through acid and alkali dissolution processes, so that the carbon residue particles form activated carbon with a well-developed pore structure.

[0111] In the present invention, activated carbon, due to its well-developed pore structure and large specific surface area, forms abundant active sites on its surface due to the presence of various functional groups. Under certain conditions, it possesses the properties of accepting and donating electrons, thus providing electrochemical catalysis in chemical reactions. Furthermore, during the chemical reaction between the gasified slag and the polyacid, hydrogen peroxide, perchloric acid or chloric acid, chlorous acid, or hypochlorous acid is added to the reaction in appropriate proportions. Due to their strong oxidizing properties, hydrogen atoms are provided during the chemical reaction, allowing the hydrogen ions ionized from the polyacid to reach equilibrium with the oxygen ions ionized from the accelerator. This catalytic action of the activated carbon allows the electrochemical reaction to be more effective.

[0112] In the present invention, although the aqua regia effect of polyacids can enhance the oxidation reaction with metal ions, the polyacids have extremely strong oxidizing and corrosive properties, which weaken the corrosion resistance of the reactor during the reaction process and produce toxic gases such as HCl, SO2, and NO2. Based on this, the method for extracting aluminum and iron of the present invention uses a retting neutralization method to mix and store the fumed slag with the polyacid in a container with high corrosion resistance, and then allow it to react statically in a retting manner. Because this reaction method does not require dynamic stirring or solid-liquid collision to increase the reaction rate, the frequency of corrosion factors disturbing the equipment is reduced. On the other hand, the residual carbon in the fumed slag components has a developed pore structure and a large specific surface area, which can buffer the intensity of the chemical reaction. At the same time, activated carbon has abundant active sites. Under certain conditions, it can accept or donate electrons, promote the regulation and balance of the central electrons and coordinated electrons of the reactants, change the electronic structure of the reactant molecules, and affect their reaction properties. Moreover, the active sites on the surface of the activated carbon are further enhanced in the presence of a catalytic promoter, thereby further improving the oxidation potential and conversion efficiency of the chemical reaction.

[0113] In the present invention, because the composting neutralization reaction is a static reaction, the presence of activated carbon can, on the one hand, assist the chemical reaction, and on the other hand, resolve the extreme chemical capacity in the reaction, so the risk of strong corrosion of equipment and facilities can be overcome.

[0114] In the present invention, the extraction of aluminum and iron from gasified slag is achieved through acid dissolution. Aluminum and iron are originally impurities in coal and are hidden in the carbon residue. When the highly oxidizing polyacid reacts with them, due to the intense intensity, HCl, SO2, and NO2 poisonous gases are decomposed in the reaction. However, while the polyacid dissolves the aluminum and iron components, it also leaves cavities in the coal particles. These cavities have strong polarity, a developed pore structure, and a strong dispersion force, thus having a strong adsorption capacity. Because the chemical reaction first occurs inside the composting reactants, the toxic gases thus generated diffuse from the inside to the outside. The pore structure in the carbon residue provides the conditions and advantages for preferential adsorption. Therefore, most of the toxic gases are adsorbed by the activated carbon's own adsorption function, and are dissolved and converted into new solvents through the water-soluble desorption function, making it have both adsorption and detoxification functions and solvent regeneration functions.

[0115] In the present invention, the ammonia replacement reaction involves the replacement of the reaction products, aluminate and ferrite, with ammonium ions. The mixed slurry of slag, aluminate, and ferrite is filtered through a plate-and-frame filter press to remove the aluminate and ferrite solution, which is then separated from the slag. Ammonia gas or aqueous ammonia is then introduced into the aluminate and ferrite clear solution to adjust its pH. Practical observations have shown that when aqueous ammonia is added to a mixed solution of aluminum and iron polyacids at a temperature of 25-50°C, brown crystals precipitate when the pH of the mixed solution reaches 5. Analysis shows that the main component of these crystals is ferric hydroxide. When the pH is raised to 5-9, the precipitated crystals exhibit a light green color. Analysis shows that the main component of these crystals is aluminum hydroxide. This demonstrates that when the temperature of the mixed solution is maintained at 25-50°C and aqueous ammonia is added to adjust the pH, ferric hydroxide precipitates when the pH is 5 or less. When the pH is raised to between 5 and 9, aluminum hydroxide precipitates. Therefore, a pH value of 5 is used as the dividing line for extracting ferric hydroxide and aluminum hydroxide from a mixed solution of aluminate and ferrite, and the pH value of the solution is controlled to achieve the separation of ferric hydroxide and aluminum hydroxide.

[0116] In the present invention, aluminum hydroxide is replaced by an ammonia replacement reaction in an aluminate solution, the aluminum hydroxide is dried at a temperature of 140-150°C to produce γ-type alumina, and then calcined at a temperature of 900-1200°C to produce α-alumina. Since the generated aluminum hydroxide precipitate has a small particle size and high viscosity, it is difficult to filter and dry it in subsequent treatments, and it is not easy to process it by conventional filter pressing and drying methods. Therefore, in addition to preparing alumina by drying and calcining aluminum hydroxide, the present invention also uses a hydrochloric acid conversion method to prepare aluminum chloride from aluminum hydroxide, and then dehydrates and dries it to prepare an aluminum chloride product.

[0117] In the present invention, aluminum hydroxide is produced by decomposing polyacid aluminum. Aluminum hydroxide has special physical and chemical properties due to the presence of water of crystallization. Its small particle size and high content of water of crystallization lead to high viscosity of the material, which is difficult to process in the subsequent process and has a narrow market for product applications. Although the process of making it into γ-type alumina is simple (only ordinary drying is required) and energy consumption is low (generated at a temperature of 140-150°C), the product has large physical property defects (small particle size and low density), a narrow application range, and a bleak market prospect. Although the application range of it is wide, the production process is complicated and energy consumption is high. Therefore, the present invention preferably converts part of the aluminum hydroxide into an aluminum chloride product through a hydrochloric acid conversion method, and converts part of the aluminum hydroxide into alumina through drying and calcining.

[0118] In the present invention, the ammonium ions in the polyacid ammonium solution (a mixture of ammonium sulfate, ammonium chloride, and ammonium nitrate) are weakly alkaline ions and cannot be completely ionized. Therefore, hydrated ammonia is present in the polyacid ammonium solution. Since ammonia molecules escape when the hydrated ammonia is heated to above 90°C, the escaped ammonia molecules are carried out through the ammonia escape channel, thereby destroying the ionization equilibrium of the polyacid ammonium solution, causing the reaction to proceed in the direction of ammonia escape, and more ammonia molecules are carried out, thereby ultimately obtaining a solution containing dilute sulfuric acid, dilute hydrochloric acid, and dilute nitric acid. Therefore, dilute sulfuric acid, dilute hydrochloric acid, and dilute nitric acid can be obtained from the polyacid ammonium solution by ammonia evaporation, and their decomposition method conforms to the principle of chemical reaction equilibrium.

[0119] As for the decomposition temperature of polybasic ammonium acid solution, practice has shown that when impurities are present, the thermal decomposition mechanism of ammonium nitrate below 150°C is: 4HNO3→4NO2+2H2O+O2;

[0120] NH4NO3+2NO2→N2+H2O+HNO3;

[0121] The mechanism of the effect of acid on the decomposition reaction of ammonium nitrate is:

[0122]

[0123] NO2 + +NH3→NH3NO2 + →N2O+H3O + .

[0124] Therefore, H2SO4, HNO3, HCl, etc. can accelerate the decomposition of ammonium nitrate, ammonium sulfate, and ammonium chloride. The promoting effect of monoacids on ammonium salts is mainly to reduce the initial decomposition temperature of ammonium salts; ammonium chloride and ammonium nitrate in polyacid ammonium undergo thermal decomposition in the form of autocatalytic reactions. It can be seen that acids can cause ammonium sulfate, ammonium nitrate, and ammonium chloride solutions to generate ammonia molecules and dilute sulfuric acid, dilute nitric acid, and dilute hydrochloric acid at relatively low temperatures (above 90°C). Therefore, since ammonium sulfate, ammonium nitrate, and ammonium chloride solutions are weakly acidic, their solutions contain a small amount of H+ , and as ammonia molecules are continuously taken out, the decomposition reaction of ammonium sulfate, ammonium nitrate and ammonium chloride solutions is positively promoted, thereby obtaining a solution containing dilute sulfuric acid, dilute nitric acid and dilute hydrochloric acid.

[0125] Specifically, the polyacid ammonium solution includes ammonium ions, sulfate ions, nitrate ions, and chloride ions. In a liquid environment, the density of ammonium ions is lower than that of other polyacid ions, which makes the ammonium ions easily volatile when heated. Through practical observation, when the polyacid ammonium is heated above 90°C, gaseous ammonia escapes with the water vapor, the gas is alkaline, and the pH value is greater than 7. When a certain amount of gas escapes, the gas is close to neutral, and the remaining liquid is acidic, with a pH value less than 7; but if the concentration of the polyacid ammonium solution increases to supersaturation due to water evaporation, the polyacid ammonium precipitates in the form of crystals, and decomposition stops at this time. Through laboratory analysis, when the polyacid ammonium solution is heated below the saturated solubility, the alkaline molecules that escape with the water vapor are ammonia molecules, and the components remaining in the liquid are sulfuric acid, nitric acid, and hydrochloric acid. This shows that when the polyacid ammonium solution is heated to above 90°C and can always maintain a dynamic equilibrium where the concentration of the polyacid ammonium solution is less than the supersaturated solubility, the polyacid ammonium solution can decompose. During the decomposition process, the alkaline molecules that escape with the water vapor are ammonia molecules, and the acidic components that remain in the water are polyacids.

[0126] In the thermal decomposition process, the polyacid ammonium generated by the replacement reaction is heated to a temperature greater than 90°C in the pyrolyzer. While maintaining the polyacid ammonium solution at a continuously lower solubility than the supersaturated solubility, the escaped ammonia gas is introduced into the ammonia replacement system through a pipeline for use, and the polyacid in the residual liquid is modulated and returned to the aluminum dissolution process. This invention realizes the recycling of waste gas and waste liquid.

[0127] In the present invention, the amount of silica to be extracted is determined based on the residual alumina content in the residue after acid dissolution and aluminum extraction. The sodium hydroxide required for the reaction is calculated based on a 1:1 molar ratio of alumina to silica, and a solution is prepared. The prepared sodium hydroxide solution is mixed with the residue, and the solid and liquid materials are evenly mixed in a blender to form a semi-fluid slurry. The mixed slurry is introduced into a composting reactor via a delivery pump and allowed to react for 8 to 12 hours. Under the catalytic promotion of the activated carbon in the residue, the sodium hydroxide dissolves the alumina to form sodium aluminate and dissolves the silica to form sodium silicate. The reacted clinker is sent to a silicon extraction and washing dissolution vessel, and the washing, thickening separation, and plate and frame filter pressing of the aluminum dissolution process are repeated. The clear liquid is introduced into an acid ion exchanger to absorb carbon dioxide from the dry tail gas, decomposing the sodium aluminate and sodium silicate to replace aluminum hydroxide, silicic acid, and sodium carbonate. Aluminum hydroxide and silicic acid are filtered through a plate and frame filter press. The filtered sodium carbonate supernatant is then reacted with calcium hydroxide through a causticization reaction to produce calcium carbonate and sodium hydroxide. The calcium carbonate is made into a by-product and the sodium hydroxide is recycled.

[0128] In the present invention, the filter cake obtained by pressure filtration in the silicon dissolving process is fed into the second silicon dissolving process, and the filter cake obtained by pressure filtration after acid ion exchange is made into molecular sieve hollow particle products.

[0129] In the present invention, the silicon dioxide content of the first silicon dissolving residue is analyzed, and the amount of sodium hydroxide required for silicon dissolving is calculated according to the relative molecular mass of the remaining silicon dioxide to prepare a sodium hydroxide solvent. The sodium hydroxide solvent is mixed and the first silicon dissolving process is repeated to separate the generated liquid from the residue. The mixture is then separated by a thickener and plate-and-frame filter press. The reaction-completed mixture is washed with clean water to dissolve the sodium silicate solution. The sodium silicate solution is then filtered out and separated from the filter cake by a plate-and-frame filter press. The solid carbon residue remaining in the filter cake is washed with clean water to wash out the remaining residual salt, and then dried and activated to make activated carbon or added to fly ash or coal gangue for reuse in a comprehensive utilization process. The sodium silicate clear liquid filtered out by the filter press absorbs carbon dioxide in the process tail gas to complete acid ion exchange to replace silicic acid and sodium carbonate. Because the conditions for the generation of silicic acid are different, it exists in the form of orthosilicic acid. The surface network structure of orthosilicic acid crystals is loose, and it is in the form of small molecules. The structure is unstable and soluble in water and acid solutions. In order to optimize and improve its material properties, the present invention uses a hydrothermal synthesis method to convert it into metasilicic acid under a boiling environment greater than 102°C, and then dehydrates and dries it to produce a silicon dioxide product.

[0130] In the present invention, coal particles are rapidly cracked under high temperature conditions during the gasification reaction. This thermal cracking not only volatilizes volatile substances, but also gasifies most of the carbon elements into carbon monoxide in an atmosphere where carbon reaches a reduced state. The remaining carbon residue relaxes its structural chains due to the high temperature and destroys the chemical bonds of the ash components, resulting in the rupture of the silicon-aluminum covalent bonds and silicon-iron covalent bonds in the ash. The aluminum, iron and silicon impurities in the carbon residue are extracted and dissolved through acid dissolution to extract aluminum and alkali dissolution to extract silicon, and acid-base double impregnation is formed, so that the carbon residue particles form activated carbon with a developed pore structure.

[0131] In the present invention, the activated carbon, due to its well-developed pore structure and large specific surface area, has abundant active sites formed on its surface due to the presence of various functional groups. Under certain conditions, it has the characteristics of accepting and donating electrons, and thus has electrochemical catalytic function in chemical reactions. Furthermore, during the chemical reaction between the gasified slag and the polyacid, hydrogen peroxide, perchloric acid or chloric acid, chlorous acid, and hypochlorous acid are added to the reaction in appropriate proportions. Due to their strong oxidizing properties, they can provide oxygen atoms in the chemical reaction, which can promote the catalytic activity of the activated carbon in the acid dissolution of aluminum and iron in the gasified slag, making the electrochemical reaction more effective in the acid dissolution of aluminum and iron.

[0132] In the present invention, because the excellent catalytic function of activated carbon produces an electrochemical boosting effect in the neutralization reaction of materials, the divergent potential energy of the chemical reaction is further enhanced under the promotion of strong oxidants such as hydrogen peroxide. Therefore, the heap neutralization method has the advantages of strong dissolving power and high reaction rate in the chemical reaction of extracting high-valent metal components from powdered solid waste. Due to the different generation pathways of gasified slag, the residual carbon itself is a catalytic carrier. The inherent catalytic carrier is impregnated with acid and alkali to make its pore structure more developed and the active sites more abundant. After multiple impregnations, the activity of the carrier becomes stronger. Therefore, the residual carbon after the impregnation of gasified slag for aluminum and silicon extraction is used as a catalytic carrier in the comprehensive utilization of fly ash and coal gangue micropowder, making it easier to achieve acid dissolution for aluminum extraction and alkali dissolution for silicon extraction.

[0133] In the present invention, fly ash is the powdered solid waste retained by dust removal after coal combustion. During the production process, combustion decomposes most of the silicate components in the ash, but there is also a small amount of undecomposed silicate components and some mullite components formed by high-temperature sintering. Because the silicate and mullite components have stable chemical structures, ordinary oxidants cannot break their chemical bonds, making them difficult to convert. Therefore, a super-strong oxidant combined with a catalyst is required to decompose them into common oxides for conversion and extraction. Therefore, the super-strong oxidizing function of a polyacid is combined with the electrochemical function of an activated carbon catalyst carrier and the help of a promoter to first decompose them into common oxides, and then dissolve and convert them into soluble salts, thereby achieving acid dissolution of fly ash to extract aluminum and iron.

[0134] In the present invention, because the gangue micropowder has not undergone high-temperature combustion, its material composition is mainly silicate, and its chemical structure is very stable. Therefore, it can only be decomposed and transformed under the action of super-strong oxidants and more active catalysts. The carbon residue in the gasification slag undergoes a series of acid and alkali impregnations during the aluminum and silicon extraction process, resulting in a highly developed pore structure and abundant active sites. Under the dual action of the super-strong acid, it can easily break the chemical bonds of the undecomposed silicates in the fly ash, making it easy to acid-dissolve the fly ash to extract aluminum and silicon. After the gasification slag is acid-dissolved and alkali-dissolved, the separated carbon residue is added to the fly ash and dissolved again with acid and alkali. After multiple impregnations, the activity of the carrier is further enhanced, the active sites are more abundant, and the electrochemical energy generated is higher, thus achieving the chemical transformation of the gangue. Based on this, the invention continues to use the gasification slag carbon residue in the dissolution and transformation of powdered solid waste, arranging the treatment order of the three solid wastes as gasification slag → fly ash → gangue micropowder, thereby achieving the comprehensive utilization of powdered solid waste.

[0135] In the present invention, the carbon residue particles in the gasification slag are subjected to the above-mentioned acid dissolution and alkali dissolution treatments and are repeatedly impregnated with acid and alkali. The carbon residue originally has a loose network structure and a developed pore structure after gasification and pyrolysis. The metal components in the impurities are dissolved by acid impregnation, and the siliceous components in the impurities are dissolved by alkali impregnation. The acid and alkali impregnation turns it into a porous material with a very developed pore structure and a huge specific surface area. At the same time, it has abundant active sites. Under certain conditions of participating in chemical reactions, it can accept or donate electrons, promote the regulation and balance of the central electrons and coordinated electrons of the reactants, change the electronic structure of the reactant molecules, and affect their reaction properties. Moreover, the active sites on the surface of activated carbon will increase the contact kinetic energy between the reactants under the action of the super-strong divergent force of the catalytic promoter H2O2, HClO4 or HClO3, HClO2, HClO, thereby increasing the reaction rate. The various catalytic activities it possesses act as catalysts that can improve the reaction efficiency in the composting reaction, and can promote the catalytic activation of the chemical reaction under the action of the promoter. Therefore, the composting neutralization reaction will have a higher reaction rate in the presence of activated carbon catalyst and promoter. Based on this, the present invention takes the comprehensive treatment of gasification slag as the prerequisite for the comprehensive treatment of fly ash and coal gangue micropowder, and uses the residual activated carbon after gasification slag treatment as a catalytic carrier for the aluminum and silicon extraction reactions of fly ash and coal gangue micropowder. With the help of the catalytic promoter H2O2, HClO4 or HClO3, HClO2, HClO, the reaction activity is enhanced and the reaction efficiency is improved.

[0136] In the present invention, the mixing and stirring machine used in the experiment is preferably a star-shaped stirrer. The stirring device is divided into two systems: revolution and rotation. The rotation system rotates around the revolution axis driven by the revolution axis chain or gear to loosen the stirring channel of the revolution arm, reduce the stirring torque load of the arm, and improve the material stirring efficiency.

[0137] In the present invention, the material washer used in the experiment is an inverted cone device arranged in rows and parallel to each other. A rotary stirrer is installed in the washer, which has a feed port, a water inlet, an overflow port, a discharge port and a steam heating pipe.

[0138] In the present invention, the thickener used in the experiment is an inverted cone container with a relatively large cross-sectional diameter. A central sleeve configured in a certain proportion is installed in the center. The upper part of the sleeve is higher than the upper edge of the thickener, and the bottom of the sleeve is at the diameter-changing part between the thickener cylinder and the cone.

[0139] In the present invention, during the acid dissolution conversion process of the gasified slag, not only aluminum oxide and iron oxide are dissolved and converted, but also the trace heavy metal elements contained therein are dissolved and converted. Common heavy metal elements in the gasified slag include nickel, mercury, lead, etc., which are converted into salts mainly composed of nickel chloride, mercuric chloride, and lead chloride during acid dissolution. Because these salt solutions have extremely low solubility, they decompose before ferrites in the replacement reaction and are replaced into hydroxides such as nickel hydroxide, mercuric hydroxide, and lead hydroxide. Since the density of these hydroxides is much greater than that of iron hydroxide, they will settle and accumulate at the bottom of the container before iron hydroxide due to gravity during sedimentation. Therefore, they are separated and extracted by density difference separation.

[0140] In the present invention, the density difference separation is achieved through a thickener. The hydroxide mixed slurry is introduced into the upper opening of the central sleeve and enters the bottom of the thickener. The continuously increasing mixed liquid returns through the bottom of the sleeve and rises from bottom to top outside the sleeve. During the rising process, the solids in the liquid settle under the action of gravity. The heavy metal hydroxide sinks quickly due to its high density and first gathers in the cone at the bottom of the thickener. After standing for a certain period of time, it is discharged from the discharge port.

[0141] In the present invention, because heavy metal hydroxides are hazardous waste substances with great environmental risks and narrow application, they cannot be used without solidification treatment. In addition, because they have cationic properties, the present invention makes them into foam molecular sieve adsorption bricks. Because they have cationic properties, they have adsorption advantages for acidic molecules. Their unique value and advantages can be reflected in adsorption bricks, thereby optimizing their utilization.

[0142] In the present invention, fly ash is the powder solid waste intercepted by dust removal after coal combustion. During the generation process, most of the silicate components in the ash are decomposed by combustion, but there are also a small number of undecomposed silicate components and some mullite components sintered due to high temperature. Coal gangue has not been burned at high temperature, and its material composition structure is mainly silicate. Because the chemical structure of silicate and mullite components is stable, ordinary oxidants cannot break their chemical bonds, so it is difficult to convert. Therefore, a super oxidant is needed in combination with a catalyst to decompose it into ordinary oxides and then convert and extract them. Therefore, the super oxidizing function of a polyacid is combined with the electrochemical function of an activated carbon catalytic carrier and the help of a promoter to first decompose it into ordinary oxides, and then dissolve and convert it into soluble salts, so as to achieve acid dissolution and aluminum and iron extraction of fly ash and coal gangue. Based on this, the present invention realizes this by tamping and neutralizing the three waste residues in a coordinated treatment process. This method promotes the reaction intensity of acid-soluble aluminum and iron and alkali-soluble silica, continues to use gasified slag and carbon residue in the dissolution and conversion of powdered solid waste, forms a synergistic effect in the treatment processes of the three solid wastes, and makes the comprehensive utilization of large-scale industrial solid waste form a large-scale circulation, large-scale combination, and large-scale through-chain.

[0143] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0144] Example 1

[0145] Pilot project for the coordinated treatment and resource utilization of industrial waste gasification slag, fly ash, coal gangue and carbon dioxide in waste gas in Tuke Industrial Park, Wushi Banner, Inner Mongolia.

[0146] The pilot test completion unit: Longyuan (Beijing) Environmental Protection Technology Co., Ltd., pilot test time: early August 2024 to the end of January 2025, pilot test method: scaled-up intermediate experiment from laboratory results to industrial application.

[0147] Pilot test contents:

[0148] 1. Selection and preparation of polyacids;

[0149] 2. Extraction and purification of aluminum oxide and silicon dioxide from the mixture of coarse and fine gasified slag;

[0150] 3. Transformation and utilization of residual carbon in gasification slag;

[0151] 4. Product processing of various products.

[0152] Purpose of pilot test:

[0153] 1. Experiment with the preparation method and positive and negative effects of polyacids, determine the efficacy and advantages of polyacids in extracting aluminum and iron from gasified slag, and resolve the safety risks of polyacids due to their strong corrosiveness during use.

[0154] 2. Compare the advantages and disadvantages of the two chemical reaction methods of liquid phase dissolution and composting neutralization in the aluminum and silicon dissolution reactions of gasified slag, and summarize the best solution for the comprehensive utilization of gasified slag.

[0155] 3. Select the conversion method and final product of each component in the gasified slag;

[0156] 4. Obtain the extraction rate and conversion rate data of each component of the gasified slag;

[0157] 5. Verify the role and effect of the polyacid aqua regia effect, catalytic carrier, and promoter in the extraction of metal components from gasified slag, observe the reaction state of the solid-liquid two-phase state during the retting neutralization reaction, and the changes in the ion diffusion characteristics under this state;

[0158] 6. Select the best facilities for each process and understand the functions and advantages of each facility;

[0159] 7. Determine the reaction mode, reaction time, and reaction temperature, and summarize the adjustment of reaction time and reaction temperature under this mode;

[0160] 8. Understand the pH value variation range at each reaction stage;

[0161] 9. Determine the method for solid-liquid separation of reaction products and the optimal separation scheme;

[0162] 10. Determine the best method for polyacid aluminum metathesis and the process route for product purification and commercialization;

[0163] 11. Compare the advantages of aluminum hydroxide, aluminum oxide and aluminum chloride and the optimal adaptability of the process flow;

[0164] 12. Treatment and utilization of waste residue and waste liquid.

[0165] Pilot operation process:

[0166] The pilot project uses fumed slag produced by the coal chemical deep processing process of xxx Energy Co., Ltd. in the Tuke Chemical Park in Wushen Banner, Inner Mongolia, as raw material, with one ton as a base unit. The fumed slag composition is: Al2O3 = 15%, Fe2O3 = 5%, SiO2 = 20%, C = 25%. Heavy metal content: HgO and NiO are less than 0.2%, and other components include CaO, MgO, and Na2O are less than 2%. H2O = 33%. Therefore, Al2O3 = 0.15 t, Fe2O3 = 0.05 t, SiO2 = 0.2 t, C = 0.25 t, heavy metal content: HgO and NiO are less than 0.002 t, other components include CaO, MgO, and Na2O are less than 0.02 t, and H2O = 0.33 t.

[0167] According to the chemical reaction formula:

[0168] 3H2SO 4(74.6％) +Al2O 3(25.4％) =Al2(SO4) 3(86.4％) +3H2O (13.6％)

[0169] 3H2SO 4(64.75％) +Fe2O 3(35.25％) =Fe2(SO4) 3(88％) +3H2O (12％)

[0170] The result is: 1 ton of mixed raw materials contains Al2O3 = 0.15 tons, with an extraction rate of 90%, that is, 0.135 tons; Fe2O3 = 0.05 tons, with an extraction rate of 90%, that is, 0.045 tons; the solvent polyacid contains 10% sulfuric acid, 10% nitric acid, and 80% hydrochloric acid, so: the extraction of alumina requires the consumption of H2SO4 = 0.3966 tons, generating Al2(SO4)3 = 0.459 tons; the consumption of HNO3 = 0.5 tons, converting to Al(N O3)3 = 0.564 tons, requiring the consumption of HCl = 0.2899 tons, which is converted into AlCl3 = 0.3533 tons; the conversion of iron oxide requires the consumption of H2SO4 = 0.0827 tons, which produces Fe2(SO4)3 = 0.1123 tons, which consumes HNO3 = 0.1081 tons, which is converted into Fe(NO3)3 = 0.1384 tons, and consumes HCl = 0.0616 tons, which is converted into FeCl3 = 0.0914 tons.

[0171] The gasified slag is conveyed into a mixing vessel via a screw conveyor. Simultaneously, a 35% hydrochloric acid solution is introduced into the vessel via an acid pump. The slag and hydrochloric acid solution are then mixed under agitation by a stirrer. Once the hydrochloric acid solution and slag are evenly mixed, a 50% sulfuric acid solution and a 50% nitric acid solution are introduced in sequence. The proportions of the various acids are calculated based on the relative molecular weights of the aluminum oxide and iron oxide in the slag. For example, 1 ton of the mixed raw material contains 0.15 tons of Al2O3, with an extraction rate of 90%, or 0.135 tons; and 0.05 tons of Fe2O3, with an extraction rate of 90%, or 0.045 tons. The polyacid solvent contains 10% sulfuric acid, 10% nitric acid, and 80% hydrochloric acid. Therefore, the H2SO4 required to extract the aluminum oxide is 0. 0.0396 tons, generating Al2(SO4)3=0.0459 tons, requiring consumption of HNO3=0.05 tons; converting to generate Al(NO3)3=0.0564 tons, requiring consumption of HCl=0.0298*8=0.2384 tons, converting to generate AlCl3=0.03533*8=0.2826 tons; extracting iron oxide consumes H2SO4=0.0082 tons, generating Fe2(SO4)3=0.0112 tons; consuming HNO3=0.0106 tons, converting to generate Fe(NO3)3=0.0136 tons; consuming HCl=0.00616*8=0.0488 tons, converting to generate FeCl3=0.0091*8=0.0728 tons. Based on 1 ton of gasified slag raw material, 0.0792 tons of 50% sulfuric acid, 0.1 tons of 50% nitric acid, and 0.139 tons of 35% hydrochloric acid were added.

[0172] After the acid and slag are mixed and stirred into a semi-fluid slurry 1, a mixture of 30% H2O2 and 25% HClO4 is introduced into the slurry as a catalytic promoter. Due to the promoter's strong oxidizing properties, its diffusion properties cause the material to expand under the influence of bubbles once mixed with the material. As the diffusion properties of the promoter gradually weaken and the foaming of the mixed slurry decreases, the slurry is pumped into each retting container in sequence. Feeding is stopped when the slurry level reaches two-thirds of the container's water level, and the container is sealed by tightening the screw cap. The material continuously releases heat due to the chemical reaction within the retting container until the material temperature reaches 70°C. Because the reaction is most intense when the heat release peaks, external heating is applied when the material temperature begins to drop, maintaining the temperature within the container between 60 and 80°C. After the acid and slag are mixed, the pH value of the initial feed liquid is less than 1. The material reaction continues and the pH value continues to rise. When the pH value of the feed liquid rises to 4, the reaction is basically completed. Unscrew the barrel cover and inject a small amount of hot water into the container. Stir and mix to enhance the fluidity of the slurry. Then use the slurry delivery pump to transport the slurry in the composting container to the material dissolver.

[0173] The slurry is fed into the feed port of the material dissolver, while clean water is simultaneously introduced into the container to mix the water and slurry. The solid-to-liquid ratio of clean water to slurry is 3:1. The slurry and clean water are continuously introduced in proportion. The rotary agitator is activated in reverse to agitate the slurry in a floating manner. The slurry and clean water are continuously introduced, and once full, the slurry overflows through the overflow port to the next container. The overflow port of the first dissolver is connected to the feed port of the second dissolver via a pipe. The overflow from the overflow port flows through the pipe to the next dissolver, and so on. During this process, the clean water continuously dilutes and dissolves the material in each dissolver. To enhance its water solubility, the slurry in the dissolver is heated with steam to maintain temperature. The slurry is washed through several dissolvers, dissolving soluble materials. The overflow from the last dissolver is pumped into the thickener.

[0174] The mixed slurry enters the bottom of the thickener through the top of the central sleeve. The increasing mixed liquid returns through the bottom of the sleeve and rises from the outside. During this rise, solids in the liquid settle under the action of gravity. The solids continue to sink, while the clear liquid continuously floats up. When the clear liquid reaches the overflow port at the top of the thickener, it flows through a conduit to a clear liquid collection container for subsequent replacement treatment. The sinking solids accumulate in the cone at the bottom of the thickener, are intermittently discharged, and then filtered through a plate and frame filter press for solid-liquid separation, resulting in slag 1 and mixed liquid 1.

[0175] The clear liquid separated by the thickener is a mixture of polyacid aluminum and polyacid iron. The two components are separated by adjusting the pH using ammonia displacement. In the displacement reactor, the reactor is first filled with a clear mixture of aluminate and ferrite. Ammonia water or ammonia gas is then added from the center sleeve and the stirring device is activated. The ammonium ions in the ammonia water react with the acid ions in the aluminate and ferrite in the mixture to form ammonium salts. The aluminate and ferrite are decomposed, and the metal ions are displaced and exist in the form of hydroxides. Because the solubility of the ferrite solution is lower than that of the aluminate, ferric hydroxide is formed before aluminum hydroxide. When the solution pH is controlled to be less than or equal to 5, brown ferric hydroxide is generated and precipitated. When the product decreases until it no longer forms, the sediment is discharged and collected from the bottom discharge port, and then ammonia water or ammonia gas is slowly added to the center sleeve. When the pH value of the solution continues to rise, a precipitate is produced and slowly settles. At this time, the color of the precipitate gradually changes from brown to light green. The precipitate generated is aluminum hydroxide. When the pH value of the solution rises to 9, the replacement reaction stops. The solid separated is aluminum hydroxide, and the component retained in the clear liquid is polybasic ammonium.

[0176] The polybasic ammonium acid is heated and decomposed in an ammonium evaporator, separating the ammonia from the polybasic acid and recycling them, ultimately yielding a solution containing dilute sulfuric acid, dilute hydrochloric acid, and dilute nitric acid. Therefore, dilute sulfuric acid, dilute hydrochloric acid, and dilute nitric acid can be obtained from the polybasic ammonium acid solution by distilling ammonia, and the decomposition process conforms to the principle of chemical reaction equilibrium.

[0177] In the thermal decomposition process, the polyacid ammonium generated by the replacement reaction is heated to 95°C in the pyrolyzer (to prevent the hydrochloric acid solution from evaporating hydrogen chloride gas when the temperature is greater than 100°C), and the polyacid ammonium solution is kept below the supersaturated solubility. The escaped ammonia gas is introduced into the ammonia replacement system through a pipeline for use, and the polyacid in the residual liquid is modulated and returned to the aluminum dissolution process.

[0178] The aluminum hydroxide precipitate is dissolved in 25wt% dilute hydrochloric acid to convert it into a saturated aluminum chloride solution. The temperature of the saturated aluminum chloride solution is lowered to the critical point of supersaturation. 35wt% concentrated hydrochloric acid is then added to the aluminum chloride solution, causing a common ion effect between the hydrochloric acid and aluminum chloride. This common ion effect dramatically reduces the solubility of the aluminum chloride solution, correspondingly increasing the solubility of aluminum sulfate and aluminum nitrate, and precipitating aluminum chloride within a certain range. The aluminum chloride is then centrifugally dehydrated and dried to produce the finished product.

[0179] The remaining components in the slag after acid dissolution and extraction of aluminum and iron are mainly residual carbon, unconverted alumina (10%), and silica. The amount of silica to be extracted is determined proportionally to the amount of alumina contained in the slag. Because the final product of the reaction is high-alumina molecular sieve, which requires a ratio of alumina to silica greater than 1:1, the amount of sodium hydroxide required to achieve a ratio of alumina to silica greater than 1:1 is calculated based on the relative molecular mass. Sodium hydroxide is prepared into a 20% solution by mass and mixed with the slag in a star-shaped blender to form a semi-fluid slurry. The slurry is then introduced into a composting and neutralization reactor and allowed to stand for the first alkaline dissolution, allowing the sodium hydroxide to dissolve the alumina to form sodium aluminate and the silica to form sodium silicate, i.e., Al2O3+2NaOH=2NaAlO2, SiO2+2NaOH=Na2SiO3+H2O.

[0180] Dissolving 0.0135 tons of aluminum oxide requires 0.01 tons of sodium hydroxide, producing 0.021 tons of sodium metaaluminate. Dissolving 0.018 tons of silicon dioxide requires 0.024 tons of sodium hydroxide, producing 0.0366 tons of sodium silicate. After the mixture is allowed to react for 9 hours, it is diluted with hot water and then introduced into a silicic acid dissolving vessel. The polyaluminum washing and dissolving steps are repeated to dissolve the sodium tetrahydroxyaluminate and sodium silicate produced after the reaction into a mixed solution. The solution is then separated by thickening in a thickener and plate and frame filter press to produce slag 2 and mixed solution 2.

[0181] Mixed liquor 2 absorbs carbon dioxide from the process off-gas in a carbonation reactor, undergoing an ion exchange reaction to produce aluminum hydroxide, silicic acid, and sodium carbonate (i.e., 2NaAlO2 + CO2 + 3H2O = 2Al(OH)3 + Na2CO3, meaning 0.021 tons of sodium aluminate react with 0.0056 tons of carbon dioxide to produce 0.0199 tons of aluminum hydroxide and 0.0135 tons of sodium carbonate). The resulting liquid is then thickened and separated in a thickener and then filtered through a plate and frame filter press to separate the aluminum hydroxide and silicic acid solids from the sodium carbonate solution. The sodium carbonate and calcium hydroxide are then causticized to produce sodium hydroxide and calcium carbonate. The sodium hydroxide is recycled to dissolve silicon in the slag, and the calcium carbonate is dried to produce a powder product.

[0182] The aluminum hydroxide and silicic acid filter cakes obtained by plate and frame pressure filtration contain crystalline water and have fine particle size. Under vibration or stirring, part of the crystalline water will separate from the crystals and become free water. Therefore, in this embodiment, the heavy metal hydroxide separated by the above-mentioned density difference separation process is mixed with the filter cake to make foam adsorption bricks.

[0183] After the first strong alkaline dissolution reaction, the remaining alumina (10% of the total amount = 0.0135 tons) and some silica (a 1:1 ratio with alumina, i.e., 0.0135 tons) are dissolved, leaving slag 2 primarily composed of residual carbon and silica. Slag 2 (silicon dioxide from the first alkali dissolution: 0.18 tons - 0.0135 tons = 0.1665 tons) is mixed with sodium hydroxide in a ratio calculated by relative molecular mass (i.e., 0.1665 tons of silica reacts with 0.222 tons of sodium hydroxide to produce 0.338 tons of sodium silicate). The slag is then retting and allowed to stand for a reaction. Under the catalytic action of the residual carbon, the sodium hydroxide dissolves the silica to produce sodium silicate. The reaction mixture is washed with clean water to dissolve the sodium silicate solution, which is then filtered through a plate and frame filter press to separate the sodium silicate solution from the filter cake. The filter cake is the slag 3. The remaining solid carbon is washed with clean water to remove the remaining residual salt, and then dried and activated to make activated carbon or added to fly ash and coal gangue for reuse in the comprehensive utilization process.

[0184] The sodium silicate clear liquid filtered by pressure filtration absorbs carbon dioxide from the process tail gas, completing an acid-based ion exchange to produce silicic acid and sodium carbonate (i.e., Na₂SiO₃+CO₂+H₂O=H₂SiO₃+Na₂CO₃; 0.338 tons of sodium silicate absorbs 0.1213 tons of carbon dioxide to produce 0.215 tons of silicic acid and 0.2924 tons of sodium carbonate). Because silicic acid is generated under different conditions, it exists in the form of orthosilicic acid. The surface network structure of orthosilicic acid crystals is loose, forming a small molecular form, which is structurally unstable and soluble in water and acid solutions. To optimize and improve its material properties, this embodiment uses a hydrothermal synthesis method to convert it into metasilicic acid under a boiling environment greater than 102°C, and then dehydrates and dries it to produce the silica product.

[0185] It can be seen from the above embodiments that the present invention provides a process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas, and processes 1 ton of gasified slag. Alumina is extracted by polyacid (H2SO4: 10%, HNO3: 10%, HCl: 10%): 0.0396 tons of H2SO4, 0.05 tons of HNO3, and 0.2384 tons of HCl are consumed; Al2(SO4)3=0.0459 tons are converted to Al(NO3)3=0.0564 tons, and AlCl3=0.2826 tons are generated; iron oxide is extracted: 0.0082 tons of H2SO4, 0.0106 tons of HNO3, and 0.0488 tons of HCl are consumed to generate Fe2(SO4)3=0.0112 tons, Fe(NO3)3=0.0136 tons, and FeCl3=0.0728 tons. Aluminate and ferrite are replaced with ammonia to produce aluminum hydroxide and ferric hydroxide. 0.0459 tons of aluminum sulfate are replaced, consuming 0.028 tons of ammonia and producing 0.0209 tons of aluminum hydroxide; 0.0564 tons of aluminum nitrate are replaced, consuming 0.0278 tons of ammonia and producing 0.0206 tons of aluminum hydroxide; and 0.2826 tons of aluminum chloride are replaced, consuming 0.2226 tons of ammonia and producing 0.1654 tons of aluminum hydroxide. 0.01123 tons of iron sulfate were replaced, 0.00309 tons of ammonia were consumed, and 0.00315 tons of iron hydroxide were produced; 0.01384 tons of iron nitrate were replaced, 0.059 tons of ammonia were consumed, and 0.0055 tons of iron hydroxide were produced; 0.07312 tons of iron chloride were replaced, 0.0464 tons of ammonia were consumed, and 0.048 tons of iron hydroxide were produced; aluminate and ferrite were replaced by ammonia, consuming a total of 0.3868 tons of ammonia and producing 0.2636 tons of aluminum hydroxide; aluminum hydroxide was dried and calcined to produce 0.140 tons of aluminum oxide; or converted into aluminum chloride by hydrochloric acid conversion method, 0.2636 tons of aluminum hydroxide were converted, 1.12 tons of hydrochloric acid were consumed, and 1.12 tons of aluminum chloride were consumed. .3733 tons; the remaining slag from the acid-soluble aluminum and iron extraction is melted by a strong alkali melting method to dissolve 0.183 tons of silicon dioxide, consume 0.246 tons of sodium hydroxide, and generate 0.374 tons of sodium silicate; the sodium silicate is subjected to ion exchange by absorbing carbon dioxide, treating 0.374 tons of sodium silicate, absorbing 0.134 tons of carbon dioxide, replacing 0.239 tons of silicic acid and 0.3249 tons of sodium carbonate; the sodium carbonate is treated by a causticizing reaction, consuming 0.2269 tons of calcium hydroxide, generating 0.3065 tons of calcium carbonate, and replacing 0.2452 tons of sodium hydroxide; the residual carbon in the gasified slag is converted into 20 tons of activated carbon by repeated acid impregnation and alkali impregnation, the surface area of ​​which is greater than 900m 2 / g. The process of the present invention treats 1 ton of gasified slag, consuming a total of 0.4786 tons of sulfuric acid, 0.6073 tons of nitric acid, and 0.3606 tons of hydrochloric acid to produce 0.2636 tons of aluminum hydroxide; 0.246 tons of sodium hydroxide and 0.2269 tons of calcium hydroxide to produce 0.215 tons of silicic acid, which, after drying and calcination, produces 0.165 tons of silicon dioxide; 0.3065 tons of calcium carbonate; and 0.2452 tons of sodium hydroxide, which are converted into 0.2 tons of activated carbon.

[0186] The present invention uses the comprehensive treatment of coal chemical waste gasification slag as the basis for extracting high-value minerals from fly ash and coal gangue, transforms the residual carbon and residue in the gasification slag into activated carbon through the treatment of the gasification slag, and makes it continue to be used in other solid waste treatments and becomes a catalyst for subsequent treatment processes. Under the electrochemical action of the polyacid aqua regia effect and the activation energy of the catalyst, the chemical reactions of extracting aluminum and silicon in each step are easily achieved; the aqua regia effect generated by the polyacid in the dissolved metal oxide is used to improve the oxidizing performance of the oxidant, and the reaction activity of the oxidant is enhanced under the electrochemical action of the catalyst and the promoter, thereby improving the oxidizing performance of the oxidant, easily destroying the chemical structure of the reactant, and easily completing the chemical transformation that is difficult to achieve in conventional reactions; the conventional dynamic chemical reaction mode is changed to a static heap retting neutralization reaction mode, so that the super acid The aluminum oxide and iron oxide in the ash are converted into soluble aluminates and ferrites in a static reaction; the pH value of the aluminate and ferrite is adjusted by the ammonia replacement method, and the iron and aluminum hydroxides are separated step by step while obtaining the hydroxide; the hydrochloric acid is added to the aluminate and ferrite solution by the hydrochloric acid adjustment method to produce a common ion effect, which promotes the rapid crystallization of aluminum chloride and separates it from the residual sulfuric acid and nitric acid; the silicon dioxide separated after aluminum extraction is statically reacted with concentrated sodium hydroxide solution in a composting container by the strong alkali dissolution method, so that the sodium hydroxide dissolves the silicon dioxide in the slag to produce sodium silicate; the sodium silicate clear liquid is replaced with silicic acid and sodium carbonate solution by absorbing carbon dioxide in the process tail gas by the carbonation method; the sodium carbonate solution is causticized with calcium hydroxide by the causticization method to produce sodium hydroxide, a circulating solvent for dissolving silicon dioxide. The carbon residue transformed in the gasification slag treatment process is repeatedly immersed in fly ash and coal gangue micropowder for aluminum and silicon extraction using continuous acid dissolution and alkali dissolution processes, so that the specific surface area of ​​the carbon residue continues to expand and the activation energy continues to increase, and finally it is transformed into activated carbon with superior performance and properties; through the modulation and use of oxidants such as H2O2, HClO4, HClO3, HClO2, HClO, the chemical reaction of composting neutralization obtains super divergent power, turning it into a promoter that can promote the chemical reaction. This invention uses a combination of strong acid, composting neutralization reaction, residual carbon impregnation modification, ammonia replacement adjustment, common ion effect accelerated crystallization, strong alkali dissolution and other processes in combination with the characteristics and advantages of various processes and technologies. While achieving the coordinated treatment and resource utilization of industrial waste gasification slag, fly ash, coal gangue and carbon dioxide in exhaust gas, it develops a huge volume of secondary resources, and makes the three solid wastes and carbon dioxide in tail gas produce a synergistic effect in the comprehensive treatment, and excavates the catalyst activated carbon that helps solid waste treatment, so that its own value is greatly improved while becoming an important intermediate in chemical reactions. The combined use of various processes ultimately achieves the purpose of comprehensive treatment and resource utilization of various solid wastes.

[0187] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas, characterized in that: The following steps are involved: Step 1): Fumed slag, hydrochloric acid solution, sulfuric acid solution, and nitric acid solution are sequentially mixed to obtain slurry 1, and a catalyst promoter is then mixed with slurry 1 to obtain slurry 2. The chemical reaction is then enhanced under the catalytic effect of the surface activity of the residual carbon and the assistance of the promoter, and retting, neutralization, washing, and filter press separation are sequentially performed to obtain slag 1 and mixed solution 1. The mixed solution 1 is a mixed solution containing aluminate and ferrite; Step 2): using an ammonia replacement method to replace the iron hydroxide and heavy metal hydroxide in the mixed solution 1, raising the pH value to replace the aluminum hydroxide precipitate and the polyacid ammonium solution, and heat-treating the aluminum hydroxide precipitate to produce the finished alumina product, or neutralizing it with hydrochloric acid to produce the finished aluminum chloride product; Step 3): Pyrolyzing the obtained polyacid ammonium solution to obtain ammonia gas and polyacid residual liquid, wherein the ammonia gas is reused in the ammonia replacement method in step 2), and the polyacid residual liquid is reused in the preparation of slurry 1; Step 4): The obtained slag material 1 is subjected to a first alkali dissolution, followed by dissolution with clean water and separation by filter pressing to obtain a mixed solution 2 and slag material 2; The mixed solution 2 is a mixed solution containing sodium silicate and sodium tetrahydroxyaluminate; Step 5): The obtained slag 2 is subjected to a second alkali dissolution, followed by water dissolution and filter press separation to obtain a mixed solution 3 and slag 3. The slag 3 is dried and activated to produce activated carbon, which is then mixed with fly ash and / or coal gangue powder as a catalyst and reused in step 1); The mixed solution 3 is a mixed solution containing sodium silicate; Step 6): the mixed solution 2 reacts by absorbing carbon dioxide produced in the process tail gas, and is filtered to obtain solid 1 and sodium carbonate solution; Solid 1 is a mixture of silicic acid and aluminum hydroxide; Step 7): the mixed solution 3 reacts by absorbing carbon dioxide produced in the process tail gas, and is filtered to obtain a silicic acid and sodium carbonate solution; Step 8): combining the sodium carbonate solutions obtained in step 6) and step 7), adding calcium hydroxide to carry out a causticization reaction to obtain a sodium hydroxide solution and calcium carbonate. The sodium hydroxide solution can be recycled, and the calcium carbonate is dried to obtain a finished product. Step 9): The silicic acid obtained in step 7) is subjected to hydrothermal synthesis and then dried to prepare a silicon dioxide product; the mixture of silicic acid obtained in step 6) and aluminum hydroxide is mixed with the heavy metal hydroxide obtained in step 2) to prepare a high-aluminum molecular sieve.

2. The process for synergistic treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1 is characterized in that: In step 1), the main components of the gasified slag include aluminum oxide and iron oxide; According to the content of aluminum oxide and iron oxide in the gasified slag, the amount of the acid is calculated and prepared according to the percentage of the mass of each acid consumed in converting aluminum oxide and iron oxide according to the chemical reaction formula; The mass concentration of the hydrochloric acid solution is 35-37%, the mass concentration of the sulfuric acid solution is 50-98%, and the mass concentration of the nitric acid solution is 50-98%. The ratio of the hydrochloric acid solution, the sulfuric acid solution, and the nitric acid solution is 5-15%:5-15%:70-90%; The catalytic effect of the surface activity of the carbon residue refers to the fact that the abundant active sites on the surface of the carbon residue have the ability to accept and donate electrons, and can produce electrochemical reactions.

3. The process for synergistic treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1, characterized in that: In step 1), the catalyst promoter includes a hydrogen peroxide solution and / or a chlorine-containing acid solution, the volume concentration of the hydrogen peroxide solution is 27.5-40%, the concentration of the chlorine-containing acid solution is 25-30%, and the chlorine-containing acid in the chlorine-containing acid solution includes one or more of HClO4, HClO3, HClO2 and HClO; The total amount of the hydrogen peroxide solution and the chlorine-containing oxygen acid solution accounts for 5-10% of the total mass of the hydrochloric acid solution, the sulfuric acid solution and the nitric acid solution.

4. A process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1 or 2, characterized in that: In step 1), the temperature of the retting and neutralization is 50 to 80° C., and the time of the retting and neutralization is 8 to 12 hours; The washing solution is clean water washing solution, and the water-to-material ratio is 3-5:

1.

5. A process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1 or 3, characterized in that: In step 2), the ammonia replacement method includes adding ammonia water or introducing ammonia gas.

6. The process for collaborative treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 5, characterized in that: In step 2), the aluminum hydroxide precipitate is heat-treated to produce alumina product, and when the temperature is 140-150° C., gamma alumina is obtained; When the heat treatment temperature is 900℃~1200℃, α-type alumina is obtained; The concentration of the hydrochloric acid solution in the hydrochloric acid neutralization reaction is ≥25wt%; The hydrochloric acid neutralization reaction is to rapidly crystallize the aluminum chloride solution to precipitate aluminum chloride crystals through the common ion effect. The crystals are aluminum chloride hexahydrate, and the mass concentration of the added hydrochloric acid is greater than 30%.

7. The process for synergistic treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1, characterized in that: In step 4), the reagent used for the first alkali dissolution is sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is 20-42%.

8. A process for the coordinated treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1 or 7, characterized in that: In step 5), the reagent used for the second alkaline dissolution is sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is 30-42%.

9. The process for collaborative treatment and resource utilization of industrial solid waste and CO2 in tail gas according to claim 1, characterized in that: In step 5), the volume ratio of the fly ash and / or coal gangue powder to the activated carbon is 1:0.2-0.5.

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