Method for treating waste incineration fly ash through plasma melting

Abstract

The invention relates to the technical field of solid waste thermochemical treatment, and provides a method for treating waste incineration fly ash through plasma melting. Fly ash is pretreated and then enters a plasma furnace to generate a solid melt, the solid melt is quenched into vitreous slag through a slag cooler, and high-temperature waste gas generated by the melting furnace enters a high-temperature waste gas pretreatment and gas treatment system to be purified into gas meeting the environmental protection standard. An active carrier of organic particles prepared from silicon resin and silicon dioxide is added into the fly ash, so that dioxin molecules and heavy metals in the fly ash are respectively and firmly wrapped by a three-dimensional network, and the harmless reduction treatment problem of dioxin and cured heavy metals is solved; meanwhile, the problems that when plasma equipment treats the waste incineration fly ash, the melting glass transition temperature is too high, and the fly ash diffuses along with tail gas in the feeding process, so that a pipeline is blocked are solved.

Description

Technical Field

[0001] The invention relates to the technical field of thermal chemical treatment of solid waste, and in particular to a method for treating waste incineration fly ash by plasma melting. Background Art

[0002] At present, the main means of harmless disposal of garbage in my country are landfill and incineration. Garbage incineration technology has gradually been widely used due to its advantages of harmlessness, reduction, and high degree of resource utilization. Toxic and harmful substances in incineration fly ash include dioxins and heavy metals such as Cd, Cr, Ni, Pb, Zn and Cu. Dioxins are highly toxic and carcinogenic, difficult to degrade and eliminate in nature, and are a persistent organic pollutant. Incineration is an important source of dioxin production in nature, and its concentration in incineration fly ash can be as high as 7.4ng-TEQ / g. The heavy metal pollution caused by improper fly ash disposal is also worthy of attention. The particle size of fly ash is generally less than 200μm, and the escaped fly ash particles are easily spread by the wind. There are many heavy metal compounds in them. Heavy metal pollution not only harms the ecological environment, but also threatens human health. In view of the threat of incineration fly ash to the ecology and humans, in 2008, my country listed fly ash from incineration of domestic waste as HW18 hazardous waste in the "National Hazardous Waste List" according to the Solid Waste Prevention and Control Law. The country also clearly stipulates that fly ash must be stabilized before entering the landfill. Therefore, the harmless resource treatment of fly ash from incineration of waste is imminent.

[0003] At present, there are three main methods for treating waste incineration fly ash at home and abroad: melting sintering, separation and extraction, solidification and stabilization. Among them, melting sintering is the method with the highest waste incineration fly ash reduction and the best solidification effect, while plasma melting has the advantages of high melting temperature and good solidification effect of heavy metals in the molten product, and has received more and more attention.

[0004] A Chinese patent with publication number CN107159678A discloses a dioxin control method in the process of iron ore sintering and co-processing garbage fly ash. The method comprises mixing and granulating four components, namely, garbage fly ash, lime milk, flammable solid fuel and sludge, and drying them to obtain small balls containing garbage fly ash; the iron ore sintering raw material is granulated and mixed with the small balls containing garbage fly ash, and the mixture is ignited and sintered after being laid. However, the method only solidifies the fly ash, and does not involve the problems of difficulty in forming a vitreous body, high melting temperature, and heavy metal seepage from the solidified fly ash.

[0005] Since a large amount of lime slurry is sprayed into the tail gas treatment system of the waste incineration plant, the fly ash has a high CaO content and a low SiO2 content, which is a glass network former, and is not easy to form a glass body. The particle size of fly ash is in the micron range, and the specific surface area of ​​fly ash is large, so it is not easy to be sent into the plasma furnace. When the furnace is under negative pressure, directly sending fly ash into the furnace will cause fly ash particles to fly into the tail gas and diffuse into the tail gas treatment system with the tail gas, resulting in problems such as excessive secondary fly ash production and low treatment efficiency; and it will block the rear section pipeline, increase the pressure of tail gas treatment, and make the treatment work unable to proceed continuously. In addition, the fly ash has a small particle size and a large specific surface area, and the friction between particles is large. In the process of sending fly ash into the plasma device, "bridging" and wall hanging phenomena will be formed, resulting in problems such as the inability to continuously send fly ash.

[0006] The Chinese patent with the publication number CN106984633B discloses a method for resource-based treatment of waste incineration fly ash using a plasma torch, wherein the raw materials are pre-treated by adding domestic waste incineration bottom slag, broken glass, construction waste and other silicon-containing wastes and high calorific value liquid hazardous wastes to the fly ash and forming them, and the treated raw materials are fed into a transferred arc plasma torch melting furnace with oxygen as the working gas through a feeding unit, and the melted fly ash melt is cooled by air to form a glass body, and the tail gas generated in the furnace is first passed through a salt collection and purification unit to remove chloride salts, and then enters an acid recovery unit to recover HCl and a SO2 recovery unit to recover SO2, so that the tail gas is harmlessly treated. This method reduces the entrainment or flue secondary fly ash phenomenon in the subsequent melting furnace or sintering process, as well as the problem of harmless treatment of tail gas, but the plasma melting technology has a high melting temperature and high energy consumption for treating fly ash, and does not consider the performance and resource utilization of the glass body generated after adding a flux.

[0007] How to lower the melting point of fly ash and reduce energy consumption, solve the secondary pollution problem of fly ash, solve the dissolution problem of heavy metals after fly ash solidification, and at the same time make the glass produced by melting have the conditions for resource utilization, this will become a problem that must be solved in the process of widespread application of this technology. Summary of the invention

[0008] In order to overcome the shortcomings and deficiencies in the prior art, the primary purpose of the present invention is to provide a method for treating waste incineration fly ash by plasma melting. The method utilizes plasma melting technology to add active carriers of organic particles into the fly ash to completely decompose dioxins, which are harmful substances in the fly ash, solidify heavy metals, and convert them into non-toxic, stable, and inert by-products. The gas generated by the melting furnace enters a gas treatment system and is processed into a gas that meets environmental protection standards, thereby achieving the harmlessness and resource utilization of the fly ash.

[0009] One of the purposes of the present invention is to provide an active carrier of organic particles, which can adsorb dioxin substances, reduce the melting temperature, and form a network structure in the system so that heavy metals are solidified in the melt.

[0010] First, a method for treating waste incineration fly ash by plasma melting is provided. After the fly ash is pretreated, the fly ash enters the plasma furnace to completely decompose the organic matter in the fly ash into small molecular substances, and then enters the slag cooler for rapid cooling, so that the solid matter produced by the melting furnace is cooled and solidified into vitreous slag. The waste gas produced by the melting furnace is pretreated with high-temperature waste gas, and then enters the gas treatment system to be treated into the gas that meets the environmental protection standards. Specifically, the following steps are included: S001, fly ash pretreatment: mix fly ash with water, dissolve soluble substances in water by physical or chemical methods, separate solid particles from liquid in fly ash by filtering and centrifugal separation to obtain pretreated fly ash; fully stir the mixture of pretreated fly ash and active carrier of organic particles at 180-200°C, and then crush, granulate and screen to obtain granular material, the particle size of the granular material is 10-20mm; S002, Plasma furnace: The above-mentioned granular materials are passed into the plasma torch melting furnace, and the furnace temperature is increased through the combustion-supporting fan, the oxygen content in the furnace is increased, and the reaction is promoted. The plasma torch generates plasma and provides a high-temperature environment. Under the action of high-temperature plasma, the organic matter in the fly ash will be completely decomposed into small molecular substances, and the organic matrix in the granular material will also generate small molecular gas, forming high-temperature exhaust gas together; the inorganic substance is melted into a solid melt, achieving the solidification of heavy metals and the decomposition of dioxins; Among them, the high temperature environment of the plasma melting furnace is 1000-1200°C, and the melting treatment time is 20-40 minutes; S003, slag cooler: After being treated by the plasma furnace, the high-temperature solid melt enters the slag cooler through the lower pipeline and is rapidly cooled by water. The solid melt is quickly cooled and solidified into vitreous slag in the slag cooler; The purpose of rapid cooling of the molten material into the slag cooler is to prevent the release of harmful substances during the cooling process and reduce the risk of secondary pollution.

[0011] S004, high-temperature exhaust gas pretreatment: high-temperature exhaust gas pretreatment includes gravity dust collector and quenching tower; high-temperature exhaust gas containing dust enters the gravity dust collector through the pipeline, and under the action of gravity, the heavier particles gradually settle to the bottom of the container and gather at the bottom. After being collected, they re-enter the fly ash pretreatment link, and the preliminarily purified exhaust gas is discharged from the top and enters the quenching tower through the pipeline. The preliminarily purified exhaust gas enters the gas treatment system through the upper pipeline of the quenching tower; During the plasma melting process, some larger particles in the fly ash may not be completely melted or re-agglomerated during the cooling process. The gravity settler captures the unmelted or re-agglomerated large particles, reducing dust entrainment or secondary fly ash in the flue, and reducing the blockage problem of exhaust gas harmless treatment.

[0012] S005, gas treatment system; the waste gas obtained after rapid cooling passes through a jet scrubber and a packed bed scrubber: the waste gas obtained after rapid cooling first passes through a jet scrubber, and the jet scrubber sprays a scrubbing liquid to absorb part of the harmful gas, and the spray scrubbing liquid is an alkaline solution; then it passes through a packed bed scrubber, and the gas is further treated by positively charged adsorption microspheres filled in the packed bed scrubber, and then passes through an SCR system to convert NOx into harmless nitrogen and water. The treated gas then passes through a vaporizer to decompose organic matter in the fly ash into clean combustible gas, and finally the purified gas is discharged through an induced draft fan.

[0013] On the one hand, the exhaust gas after the quenching tower may still be at a high temperature. After entering the jet scrubber device, the exhaust gas temperature can be further reduced, which is conducive to subsequent treatment and emission. On the other hand, the exhaust gas may contain incompletely melted fly ash particles. The jet scrubber can capture fine particles in the exhaust gas by spraying water. The acidic gas contained in the exhaust gas is absorbed by the scrubbing liquid. The packing in the packed bed scrubber provides a huge surface area, which allows more contact opportunities between the exhaust gas and the scrubbing liquid, thereby improving the purification efficiency. The exhaust gas treated by the jet scrubber may still contain trace amounts of harmful substances. Thanks to the structural characteristics of the packed bed scrubber device, the exhaust gas in the packed bed is fully in contact with the scrubbing liquid, which can more effectively remove acidic gases (such as sulfur dioxide SO2, nitrogen oxides NOx) and other harmful gases, especially for difficult-to-treat aerosol particles and volatile organic compounds VOCs. It has a good removal effect.

[0014] The SCR system is composed of heat exchanger No. 1, SCR device No. 1, SCR device No. 2 and heat exchanger No. 2. The core component of the SCR device is its catalyst bed, which is composed of a honeycomb or plate-shaped catalyst. Before the flue gas enters the catalyst bed, a reducing agent needs to be sprayed into the flue gas; the reducing agent reacts with NOx under the action of the catalyst, thereby achieving efficient removal of NOx. The catalyst can promote the chemical reaction between NOx and the reducing agent, converting NOx into harmless nitrogen and water. The catalyst can further completely decompose the dioxins escaping from the flue gas to ensure that the final discharged gas is completely free of dioxin substances. The SCR system also includes a monitoring and control system for real-time monitoring of the NOx concentration and ammonia escape in the flue gas, and adjusting the injection amount of the reducing agent as needed to ensure that the emission standards are met while avoiding excessive use of the reducing agent. The catalyst is nano carbon dioxide, and the reducing agent is ammonia or urea solution.

[0015] The vaporizer can be used to dry the flue gas if it contains more water. If the subsequent treatment equipment requires dry or specific flue gas, the vaporizer can be used as a pretreatment step to prepare the flue gas for subsequent treatment. It also includes the following two aspects: 1. Decomposition of organic matter: The vaporizer decomposes the organic matter in the fly ash into clean combustible gases, namely hydrogen, carbon monoxide and methane, through a high temperature environment. These gases can be recycled as energy.

[0016] The main function of the induced draft fan is to ensure the deep purification of the flue gas, but the induced draft fan at the end position has its specific function. 1. Maintaining the negative pressure in the furnace: The induced draft fan helps maintain the negative pressure state in the furnace, which is an important condition to ensure the stability and safety of the combustion process. The negative pressure state can prevent the smoke from leaking into the environment and ensure that the smoke is discharged smoothly through the flue. 2. Overcoming pressure loss: The induced draft fan needs to overcome the pressure loss caused by the flue gas flowing through the tail flue, gravity dust collector, jet scrubber, packed bed scrubber, No. 1 SCR device, vaporizer, No. 2 SCR device and heat exchanger and other equipment to ensure that the flue gas can flow smoothly. 3. Flue gas extraction and discharge: The induced draft fan is responsible for extracting the treated flue gas from the heat exchanger and sending it to the chimney through the flue for discharge. At this time, the flue gas has gone through multiple processing links, dust removal, desulfurization, and denitrification, ensuring that the emission meets environmental protection standards. In addition to these, there are also energy-saving optimization, flow regulation, and maintaining system balance.

[0017] High-temperature exhaust gas pretreatment first removes dust from the exhaust gas and cools it down, while the jet scrubber, packed bed scrubber, SCR system, vaporizer and induced draft machine form a complete exhaust gas treatment system. These two links together ensure the high efficiency and environmental protection of the plasma melting fly ash treatment process.

[0018] From a microscopic perspective, due to the effect of an external electric field, the medium will discharge and generate a large number of energetic electrons. Molecules will be ionized and excited due to the strong bombardment of energetic electrons, accompanied by a series of physical and chemical reactions, so that complex toxic and harmful macromolecular wastes are converted into simple, non-toxic and safe small-molecule substances, so that the wastes can be degraded and harmlessly removed; from a macroscopic perspective, arc discharge produces plasma up to 7000°C, which heats the fly ash to a very high temperature, thereby quickly and effectively destroying the waste. The combustible organic components are fully cracked and gasified, and converted into combustible gases such as carbon monoxide and hydrogen, which can be used for energy recovery. The non-combustible inorganic components are transformed into harmless slag after high-temperature plasma treatment, which can be used as building materials. The flue gas generated in the system is properly treated, realizing the harmlessness, reduction and resource utilization of fly ash. It is an advanced solid waste treatment technology that not only solves the problems of excessive secondary fly ash production, low treatment efficiency, blockage of the rear pipeline, and increased pressure on exhaust gas treatment, but also effectively solves the problem of complete decomposition of dioxin and harmful substances in fly ash and complete solidification of heavy metals. It can also convert fly ash into a stable glassy substance that is not easy to precipitate heavy metals, thereby reducing the impact on the environment.

[0019] Dioxins can be effectively decomposed in an environment with a temperature higher than 850℃ for 5 seconds. The most difficult problem to solve when removing and decomposing dioxins is that the decomposed dioxins will be regenerated when they encounter a moderate amount of heavy metals in an environment with a temperature of 300-500℃. Therefore, we provide an active carrier of organic particles, which has a large specific surface area and rich microporous structure, can effectively adsorb dioxin molecules and fix them on the surface, so that they can be effectively decomposed in a high temperature environment, and when they enter the temperature range of 300-500℃, they can isolate heavy metals and no longer regenerate.

[0020] The active carrier of the organic particles is prepared from silicone resin and silicon dioxide, specifically: S101, in a reaction kettle, methylphenyltriethoxysilane, methyltriethoxysilane and 3-aminopropylmethyldiethoxysilane are mixed with an appropriate amount of ethanol, stirred evenly, a certain mass of deionized water is added as a reaction solvent, and a certain proportion of dilute phosphoric acid is added dropwise, stirred at room temperature for 2 to 3 hours until the solution is clear, and the temperature is raised to 50 to 60° C. to react for 8 to 10 hours; after the reaction stops, the mixture is allowed to stand for 60 to 80 minutes to separate the acid-water layer, washed with water for multiple times until neutral, and then small molecules and other substances remaining in the reaction system are removed to obtain a polymer matrix with a molecular weight of 100,000 to 120,000; S102, mixing silica particles, carboxymethyl cellulose and a polymer matrix in an alcohol ether solution by a solution blending method, and stirring at high speed for 60 to 80 minutes, so that the silica particles and carboxymethyl cellulose are fully cross-linked in the matrix to form an active carrier of the organic particles; The matrix with large molecular weight is selected because it has a large number of holes at a high temperature of more than 500°C, and loses weight after escaping small molecular gases, forming particles with high porosity and high strength. At the same time, when it is combined with silica at high temperature, the silica particles can be combined with silicon oxygen. The introduction of silica particles is to introduce large particles into the matrix. When the lattice transformation of silica occurs in a high temperature environment, it can be fused with heavy metals in the garbage, making this reversible transformation irreversible. As the temperature of the melting furnace increases, the side chain groups of the matrix are oxidized and decomposed into CO2 and H2O small molecular gases. The continuous overflow of these gases causes the active carrier to expand in volume, and a semi-inorganic and semi-organic type of polymer with -Si-O-Si- as the main chain is obtained. Under certain conditions, a cross-linking reaction will occur to form a three-dimensional network structure product. This three-dimensional network structure will cross-link the fly ash melt to form a layered structure with a certain shape and strength. The generated dioxin molecules are firmly fixed in the layered structure under the action of the polarity of carbonized carboxymethyl cellulose. The heavy metals in the fly ash will also be firmly wrapped by the silicon dioxide in the three-dimensional network structure. When the dioxin molecules are decomposed at high temperatures and escape from the micropores, the heavy metals are firmly locked, making it impossible for the decomposed dioxin molecules to regenerate.

[0021] The mass ratio of 3-aminopropylmethyldiethoxysilane, methylphenyltriethoxysilane and methyltriethoxysilane in the matrix is ​​1:2-3:4-6; Among them, the No. 1 heat exchanger and the No. 2 heat exchanger, the No. 1 heat exchanger controls the temperature at 900-1000℃, and the No. 2 heat exchanger controls the temperature at 350-450℃. The functions of heat exchangers include the following two aspects: 1. Heat recovery and utilization: Recover and utilize the high-temperature heat energy in the flue gas through heat exchange, and transfer it to other media for heating, steam generation or other industrial processes, thereby improving the energy efficiency of the entire system. 2. Purification and cooling of waste gas: Treat the waste gas containing pollutants and organic matter generated in the industrial production process through the process of thermal oxidation, so that the organic matter in the flue gas is oxidized into harmless carbon dioxide and water vapor, thereby reducing the emission of atmospheric pollutants; cool the flue gas temperature of the previous unit to ensure that the treatment system of the next unit can be carried out in the optimal temperature range.

[0022] Plasma melting has its own unique advantages compared to other fly ash disposal technologies. The high temperature of the plasma flame can rapidly pyrolyze and gasify the organic matter in the fly ash, and finally convert it into simple small molecular weight substances. The active carriers of the inorganic matter and organic particles in the fly ash are melted, and after reacting for a long enough time, they are rapidly cooled to obtain a glass body, which effectively solidifies heavy metals. The glass body can be used in the fields of building materials, etc., with a high degree of resource utilization, which can save a lot of landfill land.

[0023] Among them, the addition of active carriers of organic particles can effectively fix heavy metals and dioxin molecules firmly in the micropores on the one hand, and on the other hand, it is also the matrix for forming vitreous slag. Adding an appropriate amount of active carriers of organic particles to fly ash can not only reduce the melting temperature but also promote the formation of vitreous slag, improve the density and stability of the network structure of vitreous slag, and the proportion of active carriers of organic particles directly affects the leaching concentration of heavy metals.

[0024] The packed bed scrubber, wherein the positively charged adsorption microspheres filled inside the packed bed scrubber are calcium-based montmorillonite microspheres with external positive charges prepared from montmorillonite, are specifically: Calcium-based montmorillonite is selected, and deionized water is added to the calcium-based montmorillonite, and diluted hydrochloric acid is added and stirred evenly to disperse the calcium-based montmorillonite in the diluted hydrochloric acid solution, and the temperature is raised to 60°C, sodium dodecyl sulfate is added, and the mixture is fully stirred and reacted for 1 to 2 hours to obtain a suspension of calcium-based montmorillonite, and the pH value is adjusted to 3.2 to 3.5, glutamic acid is added, and the mixture is fully stirred and reacted for 1 to 2 hours, and the suspension is taken out and centrifuged at a speed of 3000 rpm, and the suspension is washed with deionized water for 2 to 3 times to remove the hydrochloric acid, and then centrifuged again, and the solid mixture at the bottom is taken out, dried and ground at 80°C, and then sieved to obtain calcium-based montmorillonite microspheres with a particle size of 30 to 50 mm and external positive charges; wherein the mass ratio of sodium dodecyl sulfate to calcium-based montmorillonite is 1:20; and the mass ratio of glutamic acid to calcium-based montmorillonite is 1:4 to 5.

[0025] The positively charged adsorption microspheres are more likely to adsorb acidic substances under the action of the charge, and the microspheres provide a huge surface area, which allows more contact opportunities between the exhaust gas and the scrubbing liquid, thereby improving the flue gas purification efficiency.

[0026] Compared with the prior art, the complete set of plasma melting process for treating waste incineration fly ash provided by the present invention has significant effects, achieving the harmlessness, reduction and resource utilization of fly ash. It has significant effects in the following aspects: 1) The plasma melting treatment of waste incineration fly ash provided by the present invention is an advanced solid waste treatment technology. After the fly ash is pretreated, it enters the plasma furnace and then enters the slag cooler to cool and solidify the solid melt produced by the melting furnace into glass slag. The waste gas produced by the melting furnace enters the high-temperature waste gas pretreatment system and the gas treatment system to be purified into the gas that meets the emission standards. It effectively solves the problem of too high melting glass transition temperature when using plasma equipment to treat waste incineration fly ash, the problem of regeneration after high-temperature decomposition of dioxin molecules, the problem of pipeline blockage caused by the diffusion of fly ash with tail gas during the feeding process, and the problem of harmless treatment of tail gas. After the waste incineration fly ash is pretreated, it is sent to the plasma melting furnace, and the melt is effectively and continuously treated to obtain a completely harmless glass body to the environment. The tail gas of the system is deacidified and dusted harmlessly to ensure the continuous and stable operation of the system. It effectively solves the problem of heavy metals and harmful substances in fly ash, and can convert fly ash into stable glass substances to reduce the impact on the environment.

[0027] 2) The present invention provides an active carrier of organic particles, and the active carrier of organic particles is added to the fly ash to be melted to make a granular material, and the granular material is melted to obtain a molten glass body. The carrier has a large specific surface area and a rich microporous structure. On the one hand, it can effectively fix heavy metals and dioxin molecules in the micropores, wherein the dioxin molecules are firmly fixed in the network structure under the action of the polarity of carbonized carboxymethyl cellulose. The heavy metals in the fly ash will also be firmly wrapped by the silicon-oxygen bonds in the three-dimensional network structure. It can be effectively decomposed under high temperature environment, and when the reaction is completed and enters the rapid cooling stage and enters the temperature range of 300-500°C, the heavy metals can be isolated and no longer regenerated. The plasma melting technology has high energy efficiency, makes the organic matter decompose more thoroughly, and completely breaks up the organic molecules that can produce dioxins, thereby eliminating the generation of dioxins from the source, without secondary pollution; and under high temperature environment, it helps to fully melt the incineration fly ash, so that the heavy metals are more evenly distributed in the molten mixture, and the heavy metals in the molten mixture are bonded in the network, and the incineration fly ash is completely stabilized. On the other hand, it is also the matrix for forming vitreous slag. Adding an appropriate amount of active carriers of organic particles to fly ash can not only reduce the melting temperature but also promote the formation of vitreous slag, improve the density and stability of the vitreous slag network structure, and effectively inhibit the leaching of heavy metals. Reducing the melting temperature from about 1500℃ to 1000-1200℃ expands the temperature range of melting treatment, shortens the melting treatment time, saves energy consumption, reduces operating costs, and obtains glass with good mechanical properties, and its flexural strength can reach 92MPa.

[0028] 3) High-temperature waste gas pretreatment first removes dust from the waste gas and cools it down, while the jet scrubber, packed bed scrubber, SCR system, vaporizer and induced draft machine form a complete waste gas treatment system. These two links together ensure the high efficiency and environmental protection of the plasma melting fly ash treatment process, and can ensure that flue gas emissions meet strict environmental protection standards. The plasma melting fly ash treatment technology provided by the present invention represents a technological advancement in the field of solid waste treatment, and helps to promote the industry to develop in a more sustainable and environmentally friendly direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 , a graph showing the glass phase content in the glassy slag after the solid melts of Examples 1-2 and Comparative Examples 1-3 were melted at 1000° C., 1200° C. and 1500° C.; Figure 2 , System flow chart of plasma melting treatment of waste incineration fly ash; Figure 3 , a curve diagram showing the change of the molten liquid phase content with the temperature during the melting process of the solid melt of Example 1. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content described in the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally. Example 1 A method for treating waste incineration fly ash by plasma melting, firstly preparing an active carrier of organic particles, specifically: In a reaction kettle, 20 parts of methylphenyltriethoxysilane, 60 parts of methyltriethoxysilane and 10 parts of 3-aminopropylmethyldiethoxysilane are mixed with an appropriate amount of ethanol, stirred evenly, a certain mass of deionized water is added as a reaction solvent, and then dilute phosphoric acid is added dropwise, stirred at room temperature for 3 hours until the solution is clear, and the temperature is raised to 60°C for reaction for 10 hours; after the reaction stops, the acid-water layer is separated by standing for 80 minutes, washed with water several times until neutral, and then the small molecules and other substances remaining in the reaction system are removed, so as to obtain a polymer matrix with a molecular weight of 113825; 10 parts of silica particles, 10 parts of carboxymethyl cellulose and 100 parts of polymer matrix are mixed in alcohol ether solution by solution blending method and stirred at high speed for 60 minutes, so that the silica particles and carboxymethyl cellulose are fully cross-linked in the matrix to form an active carrier of organic particles.

[0031] Further, positively charged adsorption microspheres are prepared, and the calcium-based montmorillonite microspheres with external positive charge prepared from montmorillonite are specifically: 100 parts of calcium montmorillonite are selected, and the calcium montmorillonite is added to 100 parts of deionized water, and diluted hydrochloric acid is added and stirred evenly to disperse the calcium montmorillonite in the diluted hydrochloric acid solution, and the temperature is raised to 60°C, and 5 parts of sodium dodecyl sulfate are added, and the mixture is stirred fully and reacted for 2 hours to obtain a suspension of calcium montmorillonite, and the pH value is adjusted to 3.2, and 25 parts of glutamic acid are added, and the mixture is stirred fully and reacted for 2 hours, and the suspension is taken out and centrifuged at a speed of 3000 rpm, and the suspension is washed with deionized water for 3 times to remove the hydrochloric acid, and then centrifuged again, and the solid mixture at the bottom is taken out, and the mixture is dried and ground at 80°C and then sieved to obtain calcium montmorillonite microspheres with a particle size of 30 to 50 mm and with an external positive charge; and the prepared calcium montmorillonite microspheres with an external positive charge are filled into the packed bed scrubber; Finally, 200 parts of fly ash are mixed with water to remove soluble substances, and the pretreated fly ash is obtained after filtering, centrifugal separation and drying. The pretreated fly ash and 100 parts of active carrier of organic particles are mixed at 180-200°C, and then crushed, granulated and screened to obtain granular materials with an average particle size of 12 mm. The granular materials are introduced into a plasma torch melting furnace, and the furnace temperature is increased by a combustion-supporting fan to increase the oxygen content in the furnace and promote the reaction. The solid melt and high-temperature exhaust gas obtained after the melting treatment time is 1200°C and 20 minutes, the high-temperature solid melt enters the slag cooler through the lower pipeline, and is rapidly cooled and solidified into glassy slag in the slag cooler; and the high-temperature exhaust gas enters the gravity settling chamber through the upper pipeline, and then enters the quenching tower. The exhaust gas obtained after rapid cooling passes through a jet scrubber and a packed bed scrubber to remove acidic substances in the exhaust gas, and then passes through an SCR system to convert NOx into harmless nitrogen and water. The treated gas then passes through a vaporizer to decompose the organic matter in the fly ash into clean combustible gas, and finally the purified gas is discharged through an induced draft fan.

[0032] Example 2 A method for treating waste incineration fly ash by plasma melting, firstly preparing an active carrier of organic particles, specifically: In a reaction kettle, 30 parts of methylphenyltriethoxysilane, 40 parts of methyltriethoxysilane and 10 parts of 3-aminopropylmethyldiethoxysilane are added with an appropriate amount of ethanol, mixed and stirred evenly, a certain mass of deionized water is added as a reaction solvent, and then dilute phosphoric acid is added dropwise, stirred at room temperature for 3 hours until the solution is clear, and the temperature is raised to 50°C for reaction for 10 hours; after the reaction stops, the acid-water layer is separated by standing for 80 minutes, washed with water several times until neutral, and then the small molecules and other substances remaining in the reaction system are removed, and a polymer matrix with a molecular weight of 114169 is obtained; 10 parts of silica particles, 10 parts of carboxymethyl cellulose and 100 parts of polymer matrix were mixed in alcohol ether solution by solution blending method and stirred at high speed for 80 minutes, so that the silica particles and carboxymethyl cellulose were fully cross-linked in the matrix to form an active carrier of organic particles. The mass ratio of silica particles, carboxymethyl cellulose and polymer matrix was 1:1:10; Further, positively charged adsorption microspheres are prepared, and the calcium-based montmorillonite microspheres with external positive charge prepared from montmorillonite are specifically: 100 parts of calcium-based montmorillonite are selected, and the calcium-based montmorillonite is added to 100 parts of deionized water, and diluted hydrochloric acid is added and stirred evenly to disperse the calcium-based montmorillonite in the diluted hydrochloric acid solution, and the temperature is raised to 60° C., 5 parts of sodium dodecyl sulfate are added, and the mixture is stirred fully and reacted for 2 hours to obtain a suspension of calcium-based montmorillonite, and the pH value is adjusted to 3.4, 20 parts of glutamic acid are added, and the mixture is stirred fully and reacted for 2 hours, and the suspension is taken out and centrifuged at a speed of 3000 rpm, and the suspension is washed with deionized water for 3 times to remove the hydrochloric acid, and then centrifuged again, and the solid mixture at the bottom is taken out, and the mixture is dried and ground at 80° C. and then sieved to obtain calcium-based montmorillonite microspheres with a particle size of 30 to 50 mm and with an external positive charge; and the prepared calcium-based montmorillonite microspheres with an external positive charge are filled into the packed bed scrubber; 200 parts of fly ash are mixed with water to remove soluble substances, and the pretreated fly ash is obtained after filtering, centrifugal separation and drying; the pretreated fly ash and 50 parts of active carrier of organic particles are mixed at 200°C, and then crushed, granulated and screened to obtain a granular material with an average particle size of 12 mm; the granular material is passed into a plasma torch melting furnace, and the furnace temperature is increased by a combustion-supporting fan to increase the oxygen content in the furnace and promote the reaction; a solid melt and high-temperature exhaust gas are obtained after the melting treatment time is 1200°C and 30 minutes; the high-temperature solid melt enters a slag cooler through a lower pipeline, and is rapidly cooled and solidified into a glassy slag in the slag cooler; and the high-temperature exhaust gas enters a gravity settling chamber through an upper pipeline, and then enters a quenching tower. The exhaust gas obtained after rapid cooling passes through a jet scrubber and a packed bed scrubber to remove acidic substances in the exhaust gas, and then passes through an SCR system to convert NOx into harmless nitrogen and water. The treated gas then passes through a vaporizer to decompose the organic matter in the fly ash into clean combustible gas, and finally the purified gas is discharged through an induced draft fan.

[0033] Example 3 A method for treating waste incineration fly ash by plasma melting, firstly preparing an active carrier of organic particles, specifically: In a reaction kettle, 20 parts of methylphenyltriethoxysilane, 60 parts of methyltriethoxysilane and 10 parts of 3-aminopropylmethyldiethoxysilane are added with an appropriate amount of ethanol, mixed and stirred evenly, a certain mass of deionized water is added as a reaction solvent, and then dilute phosphoric acid is added dropwise, stirred at room temperature for 2 hours until the solution is clear, and the temperature is raised to 60°C for reaction for 8 hours; after the reaction stops, the acid-water layer is separated by standing for 80 minutes, washed with water for multiple times until neutral, and then the small molecules and other substances remaining in the reaction system are removed, so as to obtain a polymer matrix with a molecular weight of 110713; 10 parts of silica particles, 10 parts of carboxymethyl cellulose and 100 parts of polymer matrix are mixed in alcohol ether solution by solution blending method and stirred at high speed for 80 minutes, so that the silica particles and carboxymethyl cellulose are fully cross-linked in the matrix to form an active carrier of organic particles.

[0034] Further, positively charged adsorption microspheres are prepared, and the calcium-based montmorillonite microspheres with external positive charge prepared from montmorillonite are specifically: 100 parts of calcium-based montmorillonite are selected, and the calcium-based montmorillonite is added to 100 parts of deionized water, and diluted hydrochloric acid is added and stirred evenly to disperse the calcium-based montmorillonite in the diluted hydrochloric acid solution, and the temperature is raised to 60°C, and 5 parts of sodium dodecyl sulfate are added, and the mixture is stirred fully and reacted for 1 to 2 hours to obtain a suspension of calcium-based montmorillonite, and the pH value is adjusted to 3.5, and 25 parts of glutamic acid are added, and the mixture is stirred fully and reacted for 2 hours, and the suspension is taken out and centrifuged at a speed of 3000 rpm, and the suspension is washed with deionized water for 3 times to remove the hydrochloric acid, and then centrifuged again, and the solid mixture at the bottom is taken out, and the mixture is dried and ground at 80°C and then sieved to obtain calcium-based montmorillonite microspheres with a particle size of 30 to 50 mm and with an external positive charge; and the prepared calcium-based montmorillonite microspheres with an external positive charge are filled into the packed bed scrubber; 200 parts of fly ash are mixed with water to remove soluble substances, and the pretreated fly ash is obtained after filtering, centrifugal separation and drying; the pretreated fly ash and 100 parts of active carrier of organic particles are mixed at 200°C, and then crushed, granulated and screened to obtain a granular material with an average particle size of 18mm; the granular material is passed into a plasma torch melting furnace, and the furnace temperature is increased by a combustion-supporting fan to increase the oxygen content in the furnace and promote the reaction; a solid melt and high-temperature exhaust gas are obtained after the melting treatment time is 1200°C and 20 minutes; the high-temperature solid melt enters a slag cooler through a lower pipeline, and is rapidly cooled and solidified into a glassy slag in the slag cooler; and the high-temperature exhaust gas enters a gravity settling chamber through an upper pipeline, and then enters a quenching tower. The exhaust gas obtained after rapid cooling passes through a jet scrubber and a packed bed scrubber to remove acidic substances in the exhaust gas, and then passes through an SCR system to convert NOx into harmless nitrogen and water. The treated gas then passes through a vaporizer to decompose the organic matter in the fly ash into clean combustible gas, and finally the purified gas is discharged through an induced draft fan.

[0035] Example 4 A method for treating waste incineration fly ash by plasma melting, firstly preparing an active carrier of organic particles, specifically: In a reaction kettle, 30 parts of methylphenyltriethoxysilane, 50 parts of methyltriethoxysilane and 10 parts of 3-aminopropylmethyldiethoxysilane are added with an appropriate amount of ethanol, mixed and stirred evenly, a certain mass of deionized water is added as a reaction solvent, and then dilute phosphoric acid is added dropwise, stirred at room temperature for 3 hours until the solution is clear, and the temperature is raised to 50-60°C to react for 10 hours; after the reaction stops, the acid-water layer is allowed to stand for 60-80 minutes to separate the acid-water layer, washed with water for multiple times until neutral, and then the small molecules and other substances remaining in the reaction system are removed, so as to obtain a polymer matrix with a molecular weight of 115231; 10 parts of silica particles, 10 parts of carboxymethyl cellulose and 100 parts of polymer matrix are mixed in alcohol ether solution by solution blending method and stirred at high speed for 80 minutes, so that the silica particles and carboxymethyl cellulose are fully cross-linked in the matrix to form an active carrier of organic particles.

[0036] Further, positively charged adsorption microspheres are prepared, and the calcium-based montmorillonite microspheres with external positive charge prepared from montmorillonite are specifically: 100 parts of calcium montmorillonite are selected, and the calcium montmorillonite is added to 100 parts of deionized water, and diluted hydrochloric acid is added and stirred evenly to disperse the calcium montmorillonite in the diluted hydrochloric acid solution, and the temperature is raised to 60°C, and 5 parts of sodium dodecyl sulfate are added, and the mixture is stirred fully and reacted for 2 hours to obtain a suspension of calcium montmorillonite, and the pH value is adjusted to 3.3, and 25 parts of glutamic acid are added, and the mixture is stirred fully and reacted for 2 hours, and the suspension is taken out and centrifuged at a speed of 3000 rpm, and the suspension is washed with deionized water for 3 times to remove the hydrochloric acid, and then centrifuged again, and the solid mixture at the bottom is taken out, and the mixture is dried and ground at 80°C and then sieved to obtain calcium montmorillonite microspheres with a particle size of 30 to 50 mm and with an external positive charge; and the prepared calcium montmorillonite microspheres with an external positive charge are filled into the packed bed scrubber; 200 parts of fly ash are mixed with water to remove soluble substances, and the pretreated fly ash is obtained after filtering, centrifugal separation and drying; the pretreated fly ash and 80 parts of active carrier of organic particles are mixed at 180°C, and then crushed, granulated and screened to obtain a granular material with an average particle size of 15 mm; the granular material is passed into a plasma torch melting furnace, and the furnace temperature is increased by a combustion-supporting fan to increase the oxygen content in the furnace and promote the reaction; a solid melt and high-temperature exhaust gas are obtained after the melting treatment time is 1200°C and 20 minutes; the high-temperature solid melt enters a slag cooler through a lower pipeline, and is rapidly cooled and solidified into a glassy slag in the slag cooler; and the high-temperature exhaust gas enters a gravity settling chamber through an upper pipeline, and then enters a quenching tower. The exhaust gas obtained after rapid cooling passes through a jet scrubber and a packed bed scrubber to remove acidic substances in the exhaust gas, and then passes through an SCR system to convert NOx into harmless nitrogen and water. The treated gas then passes through a vaporizer to decompose the organic matter in the fly ash into clean combustible gas, and finally the purified gas is discharged through an induced draft fan.

[0037] Comparative Example 1, the active carrier of organic particles is replaced by an equal amount of quartz sand, and the rest is the same as in Example 1; Comparative Example 2: No silicon dioxide particles and carboxymethyl cellulose were added to the active carrier of organic particles, and the rest was the same as in Example 1; Comparative Example 3: The additive for vitrification treatment in Example 1 of Chinese Patent Publication No. CN110043905B was used in an amount of 20%, and fly ash was added; the rest was the same as Example 1. Comparative Example 4: ordinary calcium-based montmorillonite is added to the packed bed scrubber in the gas treatment system, and the No. 1 SCR device and the No. 2 SCR device catalytic device are not provided in the SCR system. The rest is the same as in Example 1.

[0038] Experimental results 1. Performance testing of glass phase in solid melt The melting points of the solid melts of Examples 1-4 and Comparative Examples 1-3 were measured, as shown in Table 1. As can be seen from Table 1, because the active carrier of organic particles was added to Examples 1-4, the melting temperature of the mixed solid melt was only about 1150°C, while the melting temperature of the melt after adding quartz sand in Comparative Example 1 was as high as 1485°C, and the melting temperature of the solid melt obtained in Comparative Example 3 was 1330°C; different raw materials have different chemical compositions, and when melted, they will form eutectic compounds with different components. The different melting points of the eutectic compounds cause the melting temperatures of the solid melts to be different. The three monomers we selected, methylphenyltriethoxysilane, methyltriethoxysilane and 3-aminopropylmethyldiethoxysilane, have different functional groups, and the synergistic effect reduces the melting temperature of the entire system. However, it is not accurate enough to judge the formation of glass only by qualitative analysis. In order to evaluate whether glass is formed after the incineration fly ash is melted, the method in GB / T 18046-2017 is used to calculate the glass phase content in the slag, and the slag with a glass phase content of more than 80% is defined as glass. The glass phase content in the slag after the solid melts of Examples 1-2 and Comparative Examples 1-3 are melted at 1000°C, 1200°C and 1500°C is as follows: Figure 1 As shown. Figure 1 It can be seen that with the increase of melting temperature, the glass phase content in all formula samples increases, so the plasma melting temperature plays a crucial role in the formation of glass. Figure 1 It can also be seen that the melting temperature of the solid melt of Example 1-2 in which the active carrier of organic particles is added is significantly reduced, and a large amount of glassy material has been formed at 1000°C.

[0039] Table 1 Performance test record of glass phase in solid melt

[0040] In order to better study the melting state of the solid melt, we detected the curve of the molten liquid phase content of the solid melt in Example 1 from the beginning of melting to complete melting as a function of temperature. From the beginning of melting to complete melting, it can be summarized into three stages. The first stage is from 600°C to 800°C, and a molten liquid phase begins to form in the system. In this stage, the molten liquid phase content is very small and the growth rate is relatively slow. The second stage is from 950°C to 1000°C, and the molten liquid phase content increases significantly from 7.20% to 43.95%. This may be because the temperature in the second stage reaches the melting temperature of the low-melting eutectic compound in the sample, and the eutectic compound begins to melt in large quantities to form a liquid phase. The third stage is from 1050°C to 1150°C, and the growth of the molten liquid phase content continues to increase, the refractory mineral phase begins to melt, and the liquid phase content reaches 95% at 1110°C, after which the system quickly reaches a completely molten state.

[0041] 2. Heavy metal curing effect test In order to deeply analyze and compare the solidification effect of heavy metals before and after plasma melting treatment, it is necessary to detect the heavy metal content in the original fly ash and the glass obtained after high-temperature melting treatment. In this paper, the US EPA3050 soil digestion method is used to digest the original fly ash and the glass after rapid cooling with nitric acid-hydrofluoric acid-perchloric acid to obtain the liquid sample to be tested, and then the detection and analysis are carried out on the inductively coupled plasma emission spectrometer.

[0042] The specific digestion steps are as follows: crush the fly ash and glass and grind them with an agate mortar to make their particle size less than 100 mesh; weigh three portions of fly ash and the glass samples obtained in Examples 1-2 and Comparative Examples 1-3 at 1.0±0.01g, place them in a polytetrafluoroethylene crucible, add 10mL HNO3, cover with a lid, and after the reaction is completed, transfer to a low-temperature heating plate and heat to dissolve for 1 hour; after cooling, add 5mL of HF and continue heating for 1 hour; after cooling, continue to add 5mL HClO4 and heat until the solution is almost dry, at which time the solution is milky white; after cooling again, add 2mL of HClO4 and continue heating until the solution evaporates to an off-white solid; continue to add 20mL2% HNO3, heat to a slight boil, remove and cool, filter, and make up to volume in a 50mL volumetric flask; finally, the heavy metal concentration in the digestion solution is detected and analyzed on ICP-OES, and the results are shown in Table 2.

[0043] Table 2 Heavy metal content monitoring record (mg / L)

[0044] As can be seen from Table 2, the content of Zn in the fly ash of garbage incineration is the highest, followed by Cu, with a content of 620.86 mg / kg; Ni and Pb contents are similar. Although the concentrations of Pb and Cd are low, their hazards are relatively large. As can be seen from Table 2, after the addition of the active carrier of organic particles, under the action of high temperature, the heavy metals are firmly fixed in the silicon-oxygen bonds and are not easy to dissolve, so the heavy metal dissolution of Examples 1-4 is very small, almost no dissolution. Table 2 combined with Table 1 shows that the melting temperature from 1200°C to 1500°C has little effect on the solidification rate of heavy metals Cd, Cr and Ni, but has a greater impact on the solidification rate of heavy metals Pb and Zn. With the increase of melting temperature, the solidification rate of heavy metal Pb decreases. At the same time, the volatility of each chemical form of heavy metal Zn increases, and the overall solidification rate is significantly reduced, so the heavy metal dissolution ratio of comparative examples 1-3 increases to varying degrees. On the one hand, it is because the solidification degree of the heavy metals in the solid melt is not high, and on the other hand, it is because the melting temperature is too high, which reduces the solidification rate of some heavy metals. The mechanical strength of the glass of Examples 1-4 and Comparative Examples 1-4 was tested, and the flexural strength of the glass obtained in the Examples can reach 92 MPa, which is higher than that of ordinary glass and can be used safely, thus realizing the resource utilization of fly ash.

[0045] 3. Detection records of purified gas discharged from the induced draft fan The purified gas discharged from the induced draft fans of Examples 1-4 and Comparative Examples 3-4 was detected by gas chromatograph, as shown in Table 3; Table 3 shows that the gas finally discharged from the induced draft fans in Examples 1-4 meets the requirements of the "Comprehensive Emission Standard for Air Pollutants" GB18918-2017. In Comparative Example 4, because ordinary calcium-based montmorillonite is added to the packed bed scrubber in the gas treatment system, the SCR system does not have SCR No. 1 and SCR No. 2 catalytic equipment, resulting in a high total nitrogen content, and a small amount of escaping dioxins is not degraded by the catalyst. The dioxins in Comparative Example 3 are likely to be analyzed as dioxins decomposed at high temperatures. After the temperature drops, because dioxins and heavy metals are not well isolated, there is a problem of reproduction.

[0046] Through plasma melting technology, the synergistic effect of various elements and functional groups in the active carrier of organic particles is used to effectively reduce the melting temperature, increase the solidification rate of heavy metals, and make the glass formed by the entire melting system more dense. In addition, the melting treatment can greatly reduce the volume and amount of incineration fly ash, and can treat organic and inorganic pollutants with uncertain contents, fully realizing the harmless treatment of incineration fly ash.

[0047] Table 3 Detection records of purified gas

[0048] The above description is only used to illustrate the technical solution of the present invention rather than to limit it. Any equal modifications and changes made to the technical solution of the present invention by ordinary persons in the art, as long as they do not deviate from the overall concept of the present invention, are still within the scope of the present invention.

Claims

1. A method for treating waste incineration fly ash by plasma melting, characterized in that: The method for treating waste incineration fly ash by plasma melting is to pre-treat the fly ash and then enter the plasma furnace, and then enter the slag cooler for rapid cooling, so that the solid melt produced by the melting furnace is cooled and solidified into glass slag, and the waste gas produced by the melting furnace is pre-treated with high-temperature waste gas, and then enters the gas treatment system for treatment into the gas that meets the environmental protection standards. Specifically, the following steps are included: S001, fly ash pretreatment: mix fly ash with water, dissolve soluble substances in water by physical or chemical methods, separate solid particles from liquid in fly ash by filtering and centrifugal separation to obtain pretreated fly ash; fully stir the mixture of pretreated fly ash and active carrier of organic particles at 180-200°C, and then crush, granulate and screen to obtain granular material, the particle size of which is 10-20mm; S002, plasma furnace: the granular materials are introduced into a plasma torch melting furnace, and the furnace temperature is increased by a combustion-supporting fan, the oxygen content in the furnace is increased, and the reaction is promoted; the plasma torch generates plasma, so that the melting furnace is in a high-temperature environment. Under the action of the high-temperature plasma, the organic matter in the fly ash is completely decomposed into small molecular substances, generating high-temperature exhaust gas, and the inorganic matter is melted into a solid melt; S003, slag cooler: After being treated by the plasma furnace, the high-temperature solid melt enters the slag cooler through the lower pipeline and is rapidly cooled by water. The solid melt is quickly cooled and solidified into vitreous slag in the slag cooler; S004, high-temperature exhaust gas pretreatment: high-temperature exhaust gas pretreatment includes gravity dust collector and quenching tower; high-temperature exhaust gas containing dust enters the gravity dust collector through the pipeline, and under the action of gravity, the heavier particles gradually settle to the bottom of the container and gather at the bottom. After being collected, they re-enter the fly ash pretreatment link, and the preliminarily purified exhaust gas is discharged from the top and enters the quenching tower through the pipeline. The preliminarily purified exhaust gas enters the gas treatment system through the upper pipeline of the quenching tower; S005, gas treatment system; the waste gas obtained after rapid cooling passes through a jet scrubber and a packed bed scrubber: the waste gas obtained after rapid cooling first passes through a jet scrubber, which sprays a scrubbing liquid to absorb part of the harmful gas, and the spray scrubbing liquid is an alkaline solution; then passes through a packed bed scrubber, and the positively charged adsorption microspheres filled in the packed bed scrubber further treat the gas, and then passes through an SCR system to convert NOx in the gas into harmless nitrogen and water, and completely decompose the residual dioxins in the gas; the treated gas then passes through a vaporizer to decompose the organic matter in the fly ash into clean combustible gas, and finally the purified gas is discharged through an induced draft fan.

2. The method for treating waste incineration fly ash by plasma melting according to claim 1, characterized in that: The active carrier of the organic particles is prepared from silicone resin and silicon dioxide, specifically: S101, in a reaction kettle, methylphenyltriethoxysilane, methyltriethoxysilane and 3-aminopropylmethyldiethoxysilane, add an appropriate amount of ethanol, mix and stir evenly, add a certain amount of deionized water as a reaction solvent, then drop dilute phosphoric acid, stir at room temperature for 2 to 3 hours until the solution is clear, heat to 50 to 60°C and react for 8 to 10 hours; after the reaction stops, stand for 60 to 80 minutes to separate the acid and water layers, wash with water several times until neutral, and then remove the small molecules and other substances remaining in the reaction system to obtain a polymer matrix with a molecular weight of 100,000 to 120,000; the mass ratio of 3-aminopropylmethyldiethoxysilane, methylphenyltriethoxysilane and methyltriethoxysilane is 1:2 to 3:4 to 6; S102, silica particles, carboxymethyl cellulose and a polymer matrix are stirred at high speed for 60 to 80 minutes in an alcohol ether solution, so that the silica particles and carboxymethyl cellulose are fully cross-linked in the matrix to form an active carrier of the organic particles.

3. The method for treating waste incineration fly ash by plasma melting according to claim 1, characterized in that: The gas treatment system comprises a jet scrubber, a packed bed scrubber, an SCR system, a vaporizer and an induced draft fan, and is a complete exhaust gas treatment system.

4. The method for treating waste incineration fly ash by plasma melting according to claim 1, characterized in that: The SCR system is composed of a No. 1 heat exchanger, a No. 1 SCR device, a No. 2 SCR device and a No. 2 heat exchanger. The core component of the SCR device is its catalyst bed, which is composed of a honeycomb or plate-shaped catalyst. Before the exhaust gas enters the catalyst bed, a reducing agent is sprayed into the exhaust gas. The reducing agent reacts with NOx under the action of the catalyst to convert NOx into harmless nitrogen and water. The catalyst further completely decomposes dioxins escaping at high temperatures. The SCR system also includes a monitoring and control system to monitor the NOx concentration and ammonia escape amount in real time in the flue gas. The catalyst is nano titanium dioxide, and the reducing agent is ammonia or urea solution.

5. The method for treating waste incineration fly ash by plasma melting according to claim 1, characterized in that: The packed bed scrubber is filled with positively charged adsorption microspheres, which are calcium-based montmorillonite microspheres with positive charges on the outside prepared from montmorillonite. Specifically, Calcium-based montmorillonite is selected, and deionized water is added to the calcium-based montmorillonite, and diluted hydrochloric acid is added and stirred evenly to disperse the calcium-based montmorillonite in the diluted hydrochloric acid solution, and the temperature is raised to 60°C, sodium dodecyl sulfate is added, and the mixture is fully stirred and reacted for 1 to 2 hours to obtain a suspension of calcium-based montmorillonite, and the pH value is adjusted to 3.2 to 3.5, glutamic acid is added, and the mixture is fully stirred and reacted for 1 to 2 hours, and the suspension is taken out and centrifuged at a speed of 3000 rpm, and the suspension is washed with deionized water for 2 to 3 times to remove the hydrochloric acid, and then centrifuged again, and the solid mixture at the bottom is taken out, dried and ground at 80°C, and then sieved to obtain calcium-based montmorillonite microspheres with a particle size of 30 to 50 mm and external positive charges; wherein the mass ratio of sodium dodecyl sulfate to calcium-based montmorillonite is 1:20; and the mass ratio of glutamic acid to calcium-based montmorillonite is 1:4 to 5.

6. The method for treating waste incineration fly ash by plasma melting according to claim 1, characterized in that: The mass ratio of the active carrier of organic particles to the pretreated fly ash is 1 to 2:

4.

7. The method for treating waste incineration fly ash by plasma melting according to claim 4, characterized in that: Heat exchanger No. 1 and heat exchanger No. 2, heat exchanger No. 1 controls the temperature at 900~1000℃, and heat exchanger No. 2 controls the temperature at 350~450℃.

8. The method for treating waste incineration fly ash by plasma melting according to claim 1, characterized in that: The high temperature environment of the plasma melting furnace is 1000-1200°C, and the melting treatment time is 20-40 minutes.

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