Method and equipment for modifying waste incineration fly ash to be used as a promoter for clean waste incineration

Abstract

Method and equipment for modifying waste incineration fly ash as a promoter for clean waste incineration. The method includes the following steps: adding a catalytic modification promoter and a heavy metal adsorption and solidification agent to the stored waste incineration fly ash, performing homogeneous mixing and aging in a homogeneous mixing device to catalytically modify the waste incineration fly ash, then aging the homogeneously modified waste incineration fly ash, and transporting and injecting it into the main combustion area in the waste incineration device. The homogeneously modified waste incineration fly ash, as a promoter for clean waste incineration, promotes the catalytic oxidation and clean incineration of waste in a high-temperature environment of 850-1050°C, and the heat energy generated by combustion is directly supplied to the boiler power generation system. The present invention also includes equipment for implementing the method. Using the method and equipment of the present invention to treat waste incineration fly ash has the advantages of low investment, low disposal cost, high resource utilization rate, simple and efficient process, and no secondary pollution.

Description

Technical Field

[0001] The present invention relates to the technology of harmless, resourceful and reduction utilization of municipal solid waste incineration fly ash, and particularly relates to a method and equipment for modifying municipal solid waste incineration fly ash as a promoter for clean incineration of garbage. Background Art

[0002] According to detection, the bulk density of municipal solid waste incineration fly ash is about 0.6 - 0.8 g / cm 3 . The main chemical components are SiO2, CaO, Al2O3, Fe2O3, MgO, etc., and it also contains chlorine element, as well as heavy metal elements such as Hg, Zn, Pb, Mn, Cu, Cr, As, and toxic and harmful pollutants such as dioxin, benzo[a]pyrene, benzo[a]anthracene, and furan. The chlorine element in the fly ash mainly exists in the forms of NaCl, KCl, etc., and the average content of the chlorine element is about 17 - 30%. If the heavy metal elements contained therein are not effectively solidified and treated, they will seep into the soil, surface water or groundwater, causing serious harm to the ecological environment. Dioxin, benzo[a]pyrene, and benzo[a]anthracene are carcinogenic; furan has anesthetic and weak irritating effects. After inhalation, it can cause headache, dizziness, nausea, vomiting, blood pressure drop, respiratory failure, and also cause liver and kidney damage and is also carcinogenic. The National List of Hazardous Wastes (2021 Edition) clearly states that municipal solid waste incineration fly ash belongs to hazardous waste, the waste category belongs to HW18 incineration disposal residue, and the hazardous waste code is 772 - 002 - 18.

[0003] In order to achieve the goal of harmless, resourceful and reduction disposal of fly ash from municipal solid waste incineration power plants, many scientific research institutions and universities at home and abroad have carried out a large number of research and experimental work on fly ash disposal. The current disposal methods of municipal solid waste incineration fly ash can be summarized into seven categories: solidification and stabilization landfill method, chemical stabilization treatment method, building material product production method, water washing desalination and cement kiln co - disposal method, melting and solidification treatment method, sintering and solidification method, and phosphoric acid washing method.

[0004] The first category, the solidification and stabilization landfill method, adopts the method of chelating solidification - landfill disposal, which is to stir, mix evenly cement, chelating agent and fly ash, and then landfill. This method has a simple process, mature technology and is widely used. However, this kind of method belongs to the volume increase of the solidified body, with a relatively high cost, poor long - term stability for dioxin and chloride salts, occupies land resources, and there are risks of secondary pollution of soil and groundwater and damage to the anti - seepage layer, and the environmental health risk is high.

[0005] The second category, the chemical stabilization treatment method, has a small volume increase, a simple process and a small investment, but there is no general - purpose chemical agent, and the long - term solidification stability for dioxin and heavy metals is poor, so it is less used.

[0006] The third category, the building material product production method, the produced building materials are relatively light in weight and have a long service life, but the process technology requirements are high, there is a risk of heavy metal leaching, the product strength is unstable, and large - scale application still needs to be verified.

[0007] The fourth category is the co - disposal method of desalting by washing in cement kilns, which can effectively achieve the reduction of fly ash waste, and fix harmful components such as heavy metals in the fly ash into the lattice of cement clinker. The current cement kiln production technology is mature, and co - disposing fly ash can save some production raw materials. However, the high chlorine content and heavy metals in fly ash can corrode the equipment of the cement kiln equipment system. If the operation is improper, it may also reduce the quality of cement, and it is easy to regenerate dioxins and cause secondary pollution. Therefore, it is necessary to strictly control the proportion of fly ash entering the kiln, and it is necessary to wash and desalt and dechlorinate when necessary.

[0008] The fifth and sixth categories are the melting and solidification treatment method and the sintering and solidification method. These two methods can effectively achieve volume reduction. Dioxins are completely decomposed at high temperatures, and heavy metals are solidified in the vitreous body. However, this method has high energy consumption and large investment, and at the same time, it is necessary to prevent secondary pollution of the manufactured products.

[0009] The seventh category is the phosphoric acid washing method. This method can change the chemical forms of most heavy metals, make them stably solidified in fly ash, and improve the thermal stability of fly ash. However, the phosphoric acid washing method has a relatively high treatment cost, and the fly ash after treatment is acidic. When used as a building material resource, it will react with alkaline cementitious materials to neutralize, hinder the hydration reaction, and affect the product performance indicators.

[0010] Currently, domestic municipal solid waste incineration power plants generally adopt the first - type disposal method, that is, the solidification and stable landfill method to dispose of fly ash. Since the toxic and harmful organic substances, heavy metal ions and mercury in the fly ash from waste incineration are only solidified and not eliminated, they may eventually still migrate out and pollute groundwater and soil, causing secondary pollution. Moreover, the comprehensive disposal cost of the mainstream safe landfill method for fly ash is high; due to the reduction combustion and incomplete combustion during the incineration process, a variety of heavy metal particles are generated, resulting in the fly ash being rich in organic pollutants such as benzo[a]pyrene, benzo[a]anthracene, dioxins, and furans. At the same time, there are a small number of unburned plastic particles in the ash residue, with a strong strange smell. During the flue gas purification process, a large amount of activated carbon is required to adsorb harmful and toxic substances such as heavy metals and dioxins. These organic pollutants with calorific value and activated carbon are finally solidified and landfilled, resulting in a waste of energy and an increase in the fly ash disposal cost.

[0011] Although the harmless, resource - based, and reduction disposal technologies for fly ash from municipal solid waste incineration power plants have developed rapidly, due to the complex diversity of the harmful components in fly ash, there is currently no simple, effective, and low - cost method or technology that can locally resource - utilize heavy metals, organic pollutants such as dioxins, and inorganic salts in fly ash, and can promote the clean combustion and pollution reduction and carbon emission reduction of municipal solid waste in waste incineration power generation enterprises. Summary of the Invention

[0012] The technical problem to be solved by the present invention is to overcome the above-mentioned defects existing in the prior art, and provide a method and equipment for modifying municipal solid waste incineration fly ash as a promoter for clean incineration of waste, which has low investment, low disposal cost, high resource utilization rate, simple and efficient process, and no secondary pollution.

[0013] The technical solution adopted by the present invention to solve its technical problems is as follows: A method for modifying municipal solid waste incineration fly ash as a promoter for clean incineration of waste, comprising the following steps: Meter and convey the stored municipal solid waste incineration fly ash, or a mixture of municipal solid waste incineration fly ash and auxiliary carbon-containing raw materials, into a modification and homogenization mixing device. At the same time, spray and add a catalytic modification promoter atomized or fluidized through a metering and feeding atomization or fluidization mechanism into the municipal solid waste incineration fly ash in the modification and homogenization mixing device, and fluidize and spray a heavy metal adsorption and solidification agent into the municipal solid waste incineration fly ash in the modification and homogenization mixing device through a heavy metal adsorption and solidification agent metering and feeding mechanism. The mixed material after modification and homogenization is conveyed to an intermediate storage bin through a feeding and lifting conveying mechanism for static aging, so that the heavy metals and odors in the municipal solid waste incineration fly ash are completely adsorbed, and at the same time, the municipal solid waste incineration fly ash is catalytically modified. The modified municipal solid waste incineration fly ash, or the municipal solid waste incineration fly ash mixed and modified with auxiliary carbon-containing raw materials, is metered through a transfer material metering and feeding mechanism and then conveyed and sprayed into the main combustion area in the waste incineration device through a powder conveying device and a spraying device in sequence. The modified and homogenized municipal solid waste incineration fly ash, as a promoter for clean incineration of waste, promotes the catalytic oxidation and clean incineration of waste in a high-temperature environment of 850-1050°C, and the heat energy generated by combustion is directly supplied to the boiler power generation system.

[0014] Further, the catalytic modification promoter is a liquid material or powder composite containing rare earth element cerium, etc. and catalytic activation elements lithium, boron, etc.

[0015] Further, the addition amount of the catalytic modification promoter is 0.3%-1.5% of the municipal solid waste incineration fly ash disposal amount.

[0016] Further, the heavy metal adsorption and solidification agent includes but is not limited to montmorillonite, or a mixture of montmorillonite and carbon. The montmorillonite is montmorillonite powder or bentonite with a montmorillonite content > 40%, and the carbon is one or more of activated carbon, coal, coke, etc.

[0017] Further, the addition amount of the heavy metal adsorption and solidification agent is 0.5%-2% of the fly ash disposal amount.

[0018] Further, the aging time ≥ 15 minutes. The purpose of aging is to ensure that the catalytic modifier fully changes the characteristics of heavy metals and toxic organic substances in the fly ash, converts all heavy metals into ionic states, adsorbs them by montmorillonite and transfers them to the layered space between the montmorillonite mineral unit cells, which is conducive to full lattice solid solution in the high-temperature flame after entering the furnace.

[0019] Further, the auxiliary carbon-containing raw material is carbon-containing solid waste or low-quality carbon-containing resources, mainly including one or more of stone coal, coal gangue, peat, industrial waste residue with high loss on ignition, carbon-containing waste or organic waste in the fields of agriculture, forestry, fishery and animal husbandry, and liquid combustibles. The dosage of the auxiliary raw material is 0%-70% of the fly ash disposal amount.

[0020] The equipment for implementing the method of using modified municipal solid waste incineration fly ash as a promoter for clean incineration of municipal solid waste in the present invention mainly includes a fly ash storage metering and feeding device, a heavy metal adsorption and solidification treatment device, a modified homogeneous mixing device, an intermediate storage and transportation device, a powder conveying device, a spraying device, and a municipal solid waste incineration device. The discharge port of the fly ash storage metering and feeding device is communicated with the feed port of the modified homogeneous mixing device. The discharge port of the heavy metal adsorption and solidification treatment device is communicated with the feed port of the modified homogeneous mixing device. The discharge port of the modified homogeneous mixing device is communicated with the intermediate storage and transportation device. The discharge port of the intermediate storage and transportation device is communicated with the feed port of the powder conveying device. The discharge port of the powder conveying device is communicated with the feed port of the spraying device. The discharge port of the spraying device is communicated with the main incineration area of the municipal solid waste incineration device.

[0021] Further, the storage metering and feeding device includes a fly ash storage mechanism, a fly ash metering and feeding mechanism, a catalytic modification promoter storage mechanism, a catalytic modification promoter metering and feeding mechanism, etc. The discharge port of the fly ash storage mechanism is communicated with the feed port of the fly ash metering and feeding mechanism. The discharge port of the fly ash metering and feeding mechanism is communicated with the feed port of the modified homogeneous mixing device. The discharge port of the catalytic modification promoter storage mechanism is communicated with the feed port of the catalytic modification promoter metering and feeding mechanism. The discharge port of the catalytic modification promoter metering and feeding mechanism is communicated with the feed port of the modified homogeneous mixing device.

[0022] Further, the heavy metal adsorption and solidification treatment device includes a heavy metal adsorption and solidification agent storage mechanism, a heavy metal adsorption and solidification agent metering and feeding mechanism, etc. The discharge port of the heavy metal adsorption and solidification agent storage mechanism is communicated with the feed port of the heavy metal adsorption and solidification agent metering and feeding mechanism. The discharge port of the heavy metal adsorption and solidification agent metering and feeding mechanism is communicated with the feed port of the modified homogeneous mixing device.

[0023] Further, the modified homogeneous mixing device includes one or more of a spiral mixing mechanism, a horizontal grinding and powder spraying mechanism, a rolling mixing and homogenizing mechanism, a Raymond powder grinding and powder spraying mechanism, an European version powder grinding and powder spraying mechanism, etc.

[0024] Further, the intermediate storage and transportation device includes one or more of a feed lifting and conveying mechanism, an intermediate storage bin, a transfer material metering and feeding mechanism, etc.

[0025] Further, the powder conveying device is one or more of powder conveying mechanisms such as wear-resistant fans, bin pneumatic conveying pumps, screw pneumatic conveying pumps, air conveying chutes, and powder conveying pumps.

[0026] Further, the injection device is one or more of injection mechanisms such as ejector mixers, fluidized mixers, and fluidized tank mixers.

[0027] Further, the domestic waste incineration device is one or more of structures such as mechanical grate incinerators, fluidized bed incinerators, rotary incinerators, and pulse throw grate incinerators.

[0028] Further, the equipment for using the modified municipal solid waste incineration fly ash as a promoter for clean incineration of municipal solid waste further includes an auxiliary raw material pretreatment device, and the auxiliary raw material pretreatment device includes one or more of an auxiliary raw material storage and feeding mechanism, a metering mechanism, a crushing mechanism, a conveying and lifting mechanism, a deironing mechanism, etc.

[0029] Technical principle and beneficial effects of the present invention:

[0030] (1) Municipal solid waste incineration fly ash, either mixed with auxiliary carbon-containing raw materials and subjected to modified homogeneous pretreatment, or after standing and aging in an intermediate storage bin. During the aging process, it is ensured that the catalytic modifier fully changes the characteristics of heavy metals and toxic organic substances in the municipal solid waste incineration fly ash. After all heavy metals are converted into ionic states, they are adsorbed by montmorillonite and transferred to the layered space between the montmorillonite mineral unit cells, which is conducive to full lattice solid solution in the high-temperature flame after entering the furnace. The modified fly ash after aging is sprayed into the combustion zone of the incinerator as a promoter for clean incineration of municipal solid waste to achieve catalytic oxidation and clean combustion of municipal solid waste. At a high temperature of 850 - 1050 °C, the inorganic salts in the municipal solid waste incineration fly ash are directly converted into combustion-supporting components and solidified in the ash slag to improve the activity of the ash slag. The organic substances in the fly ash are burned out under the action of catalytic oxidation and clean combustion promotion. The heavy metals in the municipal solid waste incineration fly ash are converted into ionic states under the action of the catalytic modifier, and are solidified into the furnace slag in ionic form by silicate groups / silicoaluminate groups under the combined action of the high-temperature flame and the heavy metal adsorption and solidification agent, thus eliminating heavy metal pollution. The inorganic substances in the municipal solid waste incineration fly ash are converted into active components in the ash slag, without generating secondary pollution, and the clean combustion technology is conducive to stabilizing the furnace condition and has no negative impact on the municipal solid waste incineration system.

[0031] (2) By adopting the catalytic oxidation and modification clean combustion promotion technology, the combustion efficiency of the municipal solid waste incinerator and the timely burnout rate of the municipal solid waste are improved, the incomplete combustion heat loss of the municipal solid waste is reduced, the content of organic pollutants and reduced heavy metals in the ash slag is effectively reduced, and at the same time, it is conducive to stabilizing the furnace condition, especially with remarkable effect during low-load stable combustion.

[0032] (3) The method of the present invention has simple process, low investment, low treatment cost, simple operation and is easy to be implemented on site; the equipment of the present invention has compact structure, reasonable combination, good integrity, high degree of mechanization and convenient operation.

[0033] (4) By using the present invention, the in-situ resource utilization of fly ash from waste incineration can be realized, which is of great significance for promoting the clean incineration, pollution reduction and carbon emission reduction transformation and upgrading of the waste incineration power generation industry. Description of the Drawings

[0034] Figure 1 is a schematic structural diagram of the equipment in Embodiment 1 of the present invention;

[0035] Figure 2 is a schematic structural diagram of the equipment in Embodiment 2 of the present invention;

[0036] Figure 3 is a schematic structural diagram of the equipment in Embodiment 3 of the present invention.

[0037] In the figure: 1 - fly ash storage metering and feeding device, 101 - fly ash storage mechanism, 102 - fly ash metering and feeding mechanism, 103 - liquid catalytic modification promoter storage mechanism, 103' - powder catalytic modification promoter storage mechanism, 104 - liquid catalytic modification promoter metering and feeding mechanism, 104' - powder catalytic modification promoter metering and feeding mechanism, 2 - heavy metal adsorption and solidification treatment device, 201 - heavy metal adsorption and solidification agent storage mechanism, 202 - heavy metal adsorption and solidification agent metering and feeding mechanism, 3 - modified homogeneous mixing device, 301 - screw mixing mechanism, 302 - horizontal grinding and powder spraying mechanism, 4 - intermediate storage and transportation device, 401 - feeding lifting and conveying mechanism, 402 - intermediate storage bin, 403 - transfer material metering and feeding mechanism, 5 - powder conveying device, 501 - wear-resistant fan, 502 - bin pneumatic conveying pump, 503 - screw pneumatic conveying pump, 6 - spraying device, 601 - ejector mixer, 602 - fluidized bed mixer, 603 - fluidized tank mixer, 7 - waste incineration device, 701 - mechanical grate incinerator, 702 - fluidized bed incinerator, 703 - rotary incinerator, 8 - auxiliary carbon-containing raw material pretreatment device, 801 - auxiliary carbon-containing raw material storage and feeding mechanism, 802 - auxiliary carbon-containing raw material metering mechanism, 803 - crushing mechanism, 804 - auxiliary carbon-containing raw material conveying and lifting mechanism, 805 - iron removal mechanism. Detailed Embodiments

[0038] The present invention will be further described below in conjunction with embodiments.

[0039] The catalytic modification promoter used in the embodiments of the present invention described below is a liquid or powder composite containing rare earth elements such as cerium and catalytic activation elements such as lithium and boron, and is a commercially available product (produced by Changsha Zichen Technology Development Co., Ltd.). Other materials or equipment, unless otherwise specified, are obtained through conventional commercial channels. Example 1

[0040] Reference Figure 1 For this example, the equipment for modifying waste incineration fly ash to be used as a promoter for clean waste incineration includes a fly ash storage mechanism 101, a fly ash metering and feeding mechanism 102, a liquid catalytic modification promoter storage mechanism 103, a liquid catalytic modification promoter metering and feeding mechanism 104, a heavy metal adsorption and solidification agent storage mechanism 201, a heavy metal adsorption and solidification agent metering and feeding mechanism 202, a screw mixing mechanism 301, a feeding lifting and conveying mechanism 401, an intermediate storage bin 402, a transfer material metering and feeding mechanism 403, a screw pneumatic conveying pump 503, an ejector mixer 601, and a mechanical grate incinerator 701. The discharge port of the fly ash storage mechanism 101 is communicated with the feed port of the fly ash metering and feeding mechanism 102, the discharge port of the fly ash metering and feeding mechanism 102 is communicated with the feed port of the screw mixing mechanism 301, the discharge port of the liquid catalytic modification promoter storage mechanism 103 is communicated with the feed port of the liquid catalytic modification promoter metering and feeding mechanism 104, the discharge port of the liquid catalytic modification promoter metering and feeding mechanism 104 is communicated with the feed port of the screw mixing mechanism 301, the discharge port of the heavy metal adsorption and solidification agent storage mechanism 201 is communicated with the feed port of the heavy metal adsorption and solidification agent metering and feeding mechanism 202, the discharge port of the heavy metal adsorption and solidification agent metering and feeding mechanism 202 is communicated with the feed port of the screw mixing mechanism 301, the discharge port of the screw mixing mechanism 301 is communicated with the feed port of the feeding lifting and conveying mechanism 401, the discharge port of the feeding lifting and conveying mechanism 401 is communicated with the feed port of the intermediate storage bin 402, the discharge port of the intermediate storage bin 402 is communicated with the transfer material metering and feeding mechanism 403, the discharge port of the transfer material metering and feeding mechanism 403 is communicated with the feed port of the screw pneumatic conveying pump 503, the discharge port of the screw pneumatic conveying pump 503 is communicated with the feed port of the ejector mixer 601, and the discharge port of the ejector mixer 601 is communicated with the main incineration furnace area of the mechanical grate incinerator 701. The feeding lifting and conveying mechanism 401 is a bucket elevator.

[0041] The fly ash used in this embodiment is from the fly ash storage bin of a mechanical grate furnace waste incineration power plant that processes 600 t of domestic waste per day. Its main chemical components (mass percentage) and elemental analysis are as follows: SiO2 22.50%, Al2O3 3.47%, Fe2O3 2.81%, CaO 27.30%, MgO 1.74%, K2O 1.55%, Na2O 2.32%, MnO 0.21%, SO3 7.24%, Cl 5.97%, C 5.27%, Zn 0.84%, Pb 1.24%, Mn 371.5 mg / kg, Cu 395.7 mg / kg, Cr 437.3 mg / kg, As 101.7 mg / kg, Sb 205.4 mg / kg, Ni 121.4 mg / kg, Ti 103.7 mg / kg, Cd 30.6 mg / kg, Ag 41.5 mg / kg, Hg 22.4 mg / kg, Co 0.01 mg / kg.

[0042] The method for modifying the waste incineration fly ash in this embodiment as a promoter for clean waste incineration is as follows: Transfer and store the fly ash from the above domestic waste incineration power plant into the fly ash storage mechanism 101, and convey it to the spiral mixing mechanism 301 through the fly ash metering and feeding mechanism 102 at a conveying rate of 1.3 t / h. At the same time, the catalytic modification promoter in the liquid catalytic modification promoter storage mechanism 103 is atomized and sprayed into the fly ash in the spiral mixing mechanism 301 through the liquid catalytic modification promoter metering and feeding mechanism 104. The addition amount of the liquid catalytic modification promoter is calculated at 0.5% of the fly ash disposal amount. The heavy metal adsorption and solidification agent in the heavy metal adsorption and solidification agent storage mechanism 201 is fluidized and sprayed into the fly ash in the spiral mixing mechanism 301 through the heavy metal adsorption and solidification agent metering and feeding mechanism 202. The addition amount of the heavy metal adsorption and solidification agent is calculated at 1.1% of the fly ash disposal amount. The modified and homogenized fly ash is conveyed to the intermediate storage bin 402 through the feed lifting and conveying mechanism 401 and left to age for 1 hour, so that the heavy metals and odors in the fly ash are completely adsorbed, and at the same time, the fly ash is fully catalytically modified. The fully modified fly ash is metered by the transfer material metering and feeding mechanism 403 and then conveyed by the spiral pneumatic conveying pump 503, and then blown from the end of the drying section of the mechanical grate incinerator 701 and both sides of the incineration furnace through the ejector mixer 601 to the main combustion section. The modified and homogenized fly ash is used as a promoter for clean domestic waste incineration to promote the catalytic oxidation and clean incineration of domestic waste in a high-temperature environment of 935 °C, and the heat energy generated by combustion is directly supplied to the steam boiler power generation system.

[0043] During the test, the domestic waste incineration power plant reported that the mechanical grate incinerator system was operating normally, the flame in the main combustion zone was thick and strong, the power generation per ton of waste increased by 2.57% year-on-year, the thermal reduction rate of fly ash was 1.42%, the thermal reduction rate of slag was 1.28%, the output of slag increased, the monitoring of flue gas pollutant emissions showed no abnormalities, and the cost of auxiliary combustion for domestic waste incineration decreased by 7.4% year-on-year. This test shows that the modification of domestic waste incineration fly ash as a method for promoting clean incineration of domestic waste has significant effects, is simple in method, and has no secondary pollution. Example 2

[0044] Refer to Figure 2, the equipment for modifying municipal solid waste incineration fly ash as a promoter for clean waste incineration in this embodiment includes a fly ash storage mechanism 101, a fly ash metering and feeding mechanism 102, a powder catalytic modification promoter storage mechanism 103', a powder catalytic modification promoter metering and feeding mechanism 104', a heavy metal adsorption and solidification agent storage mechanism 201, a heavy metal adsorption and solidification agent metering and feeding mechanism 202, a horizontal grinding and powder spraying mechanism 302, a feeding and lifting conveyor 401, an intermediate storage bin 402, a transfer material metering and feeding mechanism 403, a wear-resistant blower 501, a fluidized mixer 602, a rotary incinerator 703, an auxiliary carbonaceous raw material storage and feeding mechanism 801, an auxiliary carbonaceous raw material metering mechanism 802, an auxiliary carbonaceous raw material conveying and lifting mechanism 804, and a deironing mechanism 805. The discharge port of the fly ash storage mechanism 101 is communicated with the feed port of the fly ash metering and feeding mechanism 102, the discharge port of the fly ash metering and feeding mechanism 102 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302, the discharge port of the powder catalytic modification promoter storage mechanism 103' is communicated with the feed port of the powder catalytic modification promoter metering and feeding mechanism 104', the discharge port of the powder catalytic modification promoter metering and feeding mechanism 104' is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302, the discharge port of the heavy metal adsorption and solidification agent storage mechanism 201 is communicated with the feed port of the heavy metal adsorption and solidification agent metering and feeding mechanism 202, the discharge port of the heavy metal adsorption and solidification agent metering and feeding mechanism 202 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302, the discharge port of the auxiliary carbonaceous raw material storage and feeding mechanism 801 is communicated with the feed port of the auxiliary carbonaceous raw material metering mechanism 802, the discharge port communicated with the auxiliary carbonaceous raw material metering mechanism 802 is communicated with the feed port of the auxiliary carbonaceous raw material conveying and lifting mechanism 804, the upper front part of the auxiliary carbonaceous raw material conveying and lifting mechanism 804 is provided with a deironing mechanism 805, the discharge port of the auxiliary carbonaceous raw material conveying and lifting mechanism 804 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302, the discharge port of the horizontal grinding and powder spraying mechanism 302 is communicated with the feed port of the feeding and lifting conveyor 401, the discharge port of the feeding and lifting conveyor 401 is communicated with the feed port of the intermediate storage bin 402, the discharge port of the intermediate storage bin 402 is communicated with the transfer material metering and feeding mechanism 403, the discharge port of the transfer material metering and feeding mechanism 403 is communicated with the inlet of the wear-resistant blower 501, the outlet of the wear-resistant blower 501 is communicated with the feed port of the fluidized mixer 602, and the discharge port of the fluidized mixer 602 is communicated with the main incineration area of the rotary incinerator 703. The feeding and lifting conveyor 401 is a bucket elevator.

[0045] The auxiliary carbonaceous raw material is peat fine particle carbonaceous material, and the dosage of the auxiliary carbonaceous raw material peat is 20% of the fly ash disposal amount.

[0046] The fly ash from waste incineration used in this embodiment comes from the fly ash storage bin of a rotary waste incineration power plant that processes 300 t of domestic waste per day. Its main chemical components (mass percentage) and elemental analysis are as follows: SiO2 14.20%, Al2O3 5.31%, Fe2O3 4.42%, CaO 32.10%, MgO 2.53%, K2O 0.86%, Na2O 1.55%, MnO 0.14%, SO3 9.25%, Cl 7.53%, C 8.24%, Zn 0.61%, Pb 0.92%, Mn 218.2 mg / kg, Cu 591.4 mg / kg, Cr 362.5 mg / kg, As 103.1 mg / kg, Sb 124.5 mg / kg, Ni 94.6 mg / kg, Ti 87.8 mg / kg, Cd 21.4 mg / kg, Ag 32.3 mg / kg, Hg 30.5 mg / kg, Co 0.00 mg / kg.

[0047] The method for modifying the fly ash from waste incineration in this embodiment to be a promoter for clean waste incineration is as follows: Transfer and store the fly ash from the above domestic waste incineration power plant into the fly ash storage mechanism 101, and convey it to the horizontal grinding and powder spraying mechanism 302 through the fly ash metering and feeding mechanism 102 at a conveying rate of 0.7 t / h. At the same time, the auxiliary carbonaceous raw material storage and feeding mechanism 801 conveys the auxiliary raw material peat to the auxiliary carbonaceous raw material metering mechanism 802. After the auxiliary raw material peat is metered at 2.25 t / h, it is conveyed, de-ironed through the auxiliary carbonaceous raw material conveying and lifting mechanism 804 and the de-ironing mechanism 805, and then transferred into the horizontal grinding and powder spraying mechanism 302. At the same time, the catalytic modification promoter in the powder catalytic modification promoter storage mechanism 103' is fluidized and sprayed into the fly ash in the horizontal grinding and powder spraying mechanism 302 through the powder catalytic modification promoter metering and feeding mechanism 104'. The addition amount of the catalytic modification promoter is calculated according to 1.2% of the fly ash disposal amount. The heavy metal adsorption and solidification agent in the heavy metal adsorption and solidification agent storage mechanism 201 is fluidized and sprayed into the fly ash in the horizontal grinding and powder spraying mechanism 302 through the heavy metal adsorption and solidification agent metering and feeding mechanism 202. The addition amount of the heavy metal adsorption and solidification agent is calculated according to 0.9% of the fly ash disposal amount. The modified and homogenized fly ash and the mixed powder of the auxiliary raw material peat are conveyed to the intermediate storage bin 402 through the feeding and lifting and conveying mechanism 401 and left to age for 35 minutes, so that the heavy metals and odors in the fly ash are completely adsorbed, and at the same time, the fly ash is fully catalytically modified. The modified fly ash is metered by the transfer material metering and feeding mechanism 403 and then conveyed and blown through the wear-resistant blower 501 and the fluidized mixer 602 in sequence to the main incineration area of the rotary incinerator 703. The modified and homogenized fly ash, as a promoter for clean domestic waste incineration, realizes the catalytic oxidation and clean incineration of waste in a high-temperature environment of 960 °C, and the heat energy generated by combustion is directly supplied to the waste heat power generation system.

[0048] During the test, the domestic waste incineration power plant reported that the operating conditions of the rotary incinerator system were normal. The flame in the main combustion zone of the rotary incinerator was bright, thick and powerful. The power generation per ton of waste increased by 3.72% year-on-year. The thermal dechlorination rate of fly ash was 1.07%, and the thermal dechlorination rate of slag was 1.73%. The output of slag increased. The detection of heavy metals and chloride ions in the incineration system did not exceed the standard, and no abnormalities were found in the monitoring of flue gas pollutant emissions. The cost of auxiliary combustion for domestic waste incineration decreased by 6.1% year-on-year. This test shows that the method of using modified domestic waste incineration fly ash as a promoter for clean incineration of domestic waste has significant effects, is simple, and has no secondary pollution. Example 3

[0049] Refer to Figure 3, the equipment for modifying waste incineration fly ash as a promoter for clean waste incineration in this embodiment includes a fly ash storage mechanism 101, a fly ash metering and feeding mechanism 102, a liquid catalytic modification promoter storage mechanism 103, a powder catalytic modification promoter storage mechanism 103', a liquid catalytic modification promoter metering and feeding mechanism 104, a powder catalytic modification promoter metering and feeding mechanism 104', a heavy metal adsorption and solidification agent storage mechanism 201, a heavy metal adsorption and solidification agent metering and feeding mechanism 202, a horizontal grinding and powder spraying mechanism 302, a feeding and lifting conveyor mechanism 401, an intermediate storage bin 402, a transfer material metering and feeding mechanism 403, a bin type pneumatic conveying pump 502, a fluidized tank mixer 603, a fluidized bed incinerator 702, an auxiliary carbon-containing raw material storage and feeding mechanism 801, an auxiliary carbon-containing raw material metering mechanism 802, and a crushing mechanism 803. The discharge port of the fly ash storage mechanism 101 is communicated with the feed port of the fly ash metering and feeding mechanism 102, the discharge port of the fly ash metering and feeding mechanism 102 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302. The discharge port of the liquid catalytic modification promoter storage mechanism 103 is communicated with the feed port of the liquid catalytic modification promoter metering and feeding mechanism 104, the discharge port of the liquid catalytic modification promoter metering and feeding mechanism 104 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302. The discharge port of the powder catalytic modification promoter storage mechanism 103' is communicated with the feed port of the powder catalytic modification promoter metering and feeding mechanism 104', the discharge port of the powder catalytic modification promoter metering and feeding mechanism 104' is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302. The discharge port of the heavy metal adsorption and solidification agent storage mechanism 201 is communicated with the feed port of the heavy metal adsorption and solidification agent metering and feeding mechanism 202, the discharge port of the heavy metal adsorption and solidification agent metering and feeding mechanism 202 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302. The discharge port of the auxiliary carbon-containing raw material storage and feeding mechanism 701 is communicated with the feed port of the crushing mechanism 803, the discharge port of the crushing mechanism 803 is communicated with the feed port of the auxiliary carbon-containing raw material metering mechanism 802, the discharge port communicated with the auxiliary carbon-containing raw material metering mechanism 802 is communicated with the feed port of the horizontal grinding and powder spraying mechanism 302. The discharge port of the horizontal grinding and powder spraying mechanism 302 is communicated with the feed port of the feeding and lifting conveyor mechanism 401, the discharge port of the feeding and lifting conveyor mechanism 401 is communicated with the feed port of the intermediate storage bin 402, the discharge port of the intermediate storage bin 402 is communicated with the transfer material metering and feeding mechanism 403, the discharge port of the transfer material metering and feeding mechanism 403 is communicated with the inlet of the bin type pneumatic conveying pump 502, the outlet of the bin type pneumatic conveying pump 502 is communicated with the feed port of the fluidized tank mixer 603, and the discharge port of the fluidized tank mixer 603 is communicated with the main incineration furnace chamber of the fluidized bed incinerator 702. The feeding and lifting conveyor mechanism 401 is a bucket elevator.

[0050] The auxiliary carbonaceous raw materials described above are relatively coarse-grained carbonaceous materials such as stone coal and coal gangue. The dosage of the auxiliary carbonaceous raw materials, coal gangue and stone coal, is 40% of the fly ash disposal amount.

[0051] The fly ash used in this example comes from the fly ash storage bin of a fluidized bed municipal solid waste incineration power plant with a daily treatment capacity of 450 t of municipal solid waste. Its main chemical components (mass percentage) and elemental analysis are as follows: SiO2 20.6%, Al2O3 7.55%, Fe2O3 2.16%, CaO 25.70%, MgO 1.97%, K2O 1.85%, Na2O 0.73%, MnO 0.08%, SO3 11.85%, Cl 9.26%, C 10.58%, Zn 1.02%, Pb 0.33%, Mn 152.6 mg / kg, Cu 373.5 mg / kg, Cr 294.7 mg / kg, As 92.8 mg / kg, Sb 167.4 mg / kg, Ni 106.5 mg / kg, Ti 126.1 mg / kg, Cd 30.4 mg / kg, Ag 27.6 mg / kg, Hg 10.5 mg / kg, Co 0.01 mg / kg.

[0052] The method for modifying municipal solid waste incineration fly ash into a promoter for clean incineration of waste is as follows: Store the fly ash from the above-mentioned municipal solid waste incineration power plant in the fly ash storage mechanism 101, and convey it to the horizontal grinding and powder spraying mechanism 302 through the fly ash metering and feeding mechanism 102 at a conveying rate of 4.5 t / h. At the same time, the auxiliary carbon-containing raw material storage and feeding mechanism 701 conveys the mixture of the auxiliary carbon-containing raw materials, stone coal and coal gangue, to the crushing mechanism 803. The crushed mixture of the auxiliary carbon-containing raw materials, stone coal and coal gangue is conveyed to the horizontal grinding and powder spraying mechanism 402 at 1.8 t / h after being metered by the auxiliary carbon-containing raw material metering mechanism 802. The catalytic modification promoter in the liquid catalytic modification promoter storage mechanism 103 is atomized and sprayed into the fly ash in the horizontal grinding and powder spraying mechanism 302 through the catalytic modification promoter metering and feeding mechanism 104. The addition amount of the liquid catalytic modification promoter is calculated at 0.4% of the fly ash disposal amount. The catalytic modification promoter in the powder catalytic modification promoter storage mechanism 103' is fluidized and sprayed into the fly ash in the horizontal grinding and powder spraying mechanism 302 through the powder catalytic modification promoter metering and feeding mechanism 104'. The addition amount of the powder catalytic modification promoter is calculated at 1.0% of the fly ash disposal amount. The heavy metal adsorption and solidification agent in the heavy metal adsorption and solidification agent storage mechanism 201 is fluidized and sprayed into the fly ash in the horizontal grinding and powder spraying mechanism 302 through the heavy metal adsorption and solidification agent metering and feeding mechanism 202. The addition amount of the heavy metal adsorption and solidification agent is calculated at 0.9% of the fly ash disposal amount. The modified and homogenized fly ash and the mixed powder of the auxiliary carbon-containing raw materials, stone coal and coal gangue are conveyed to the intermediate storage bin 402 through the feeding and lifting conveyor 401 and left to age for 15 minutes, so that the heavy metals and odors in the fly ash are completely adsorbed, and at the same time, the fly ash is fully catalytically modified. The modified fly ash is metered by the transfer material metering and feeding mechanism 403 and then conveyed and sprayed to the main combustion section in the incineration furnace of the fluidized bed incinerator 702 through the bin-type pneumatic conveying pump 502 and the fluidized tank mixer 603 in sequence, and catalytic oxidation clean incineration of the waste is realized in a high-temperature environment of 910°C. The heat energy generated by combustion is directly supplied to the boiler power generation system.

[0053] During the test period, the municipal solid waste incineration power plant reported that: the operating conditions of the fluidized bed incinerator system were normal, the waste incineration in the main combustion area was in good condition, the power generation per ton of waste increased by 5.95% year-on-year, the loss on ignition of the fly ash was 1.52%, the loss on ignition of the slag was 1.34%, the slag output increased, the detection of heavy metals and chloride ions in the incineration system did not exceed the standard, the monitoring of flue gas pollutant emissions showed no abnormalities, and the cost of assisting combustion for municipal solid waste incineration decreased by 4.7% year-on-year. This test shows that the method of modifying municipal solid waste incineration fly ash into a promoter for clean incineration of municipal solid waste has remarkable effects, is simple, and has no secondary pollution.

Claims

1. A method for modifying waste incineration fly ash as a promoter for clean waste incineration, characterized in that, It includes the following steps: Meter and convey the stored incinerator fly ash, or the mixture of incinerator fly ash and auxiliary carbonaceous raw materials, into the modification and homogenization mixing device. At the same time, atomize and spray or fluidize and spray the catalytic modification promoter into the incinerator fly ash in the modification and homogenization mixing device through the metering and feeding mechanism, and fluidize and spray the heavy metal adsorption and solidification agent into the incinerator fly ash in the modification and homogenization mixing device through the heavy metal adsorption and solidification agent metering and feeding mechanism. The mixed material after modification and homogenization is conveyed to the intermediate storage bin through the feeding and lifting conveying mechanism for static aging, so that the heavy metals and odors in the incinerator fly ash are completely adsorbed, and at the same time, the incinerator fly ash is catalytically modified. The modified incinerator fly ash, or the incinerator fly ash mixed and modified with the auxiliary carbonaceous raw materials, is metered by the transfer material metering and feeding mechanism and then conveyed and sprayed to the main combustion area in the incinerator through the powder conveying device and the injection device in sequence. The modified and homogenized incinerator fly ash acts as a garbage clean incineration promoter in a high-temperature environment of 850-1050 °C to promote the catalytic oxidation and clean incineration of garbage, and the heat energy generated by combustion is directly supplied to the boiler power generation system; The catalytic modification promoter is a liquid material or powder composite containing rare earth element cerium and catalytic activation elements lithium and boron; the heavy metal adsorption and solidification agent is montmorillonite, or montmorillonite and carbon; the aging time ≥ 15 minutes.

2. The method for modifying waste incineration fly ash to be a waste clean incineration promoter according to claim 1, characterized in that, The addition amount of the catalytic modification promoter is 0.3%-1.5% of the incinerator fly ash disposal amount.

3. The method for modifying waste incineration fly ash as a waste clean incineration promoter according to claim 1 or 2, characterized in that, The montmorillonite is montmorillonite powder or bentonite with a montmorillonite content > 40%, and the carbon is one or more of activated carbon, coal, and coke; the addition amount of the heavy metal adsorption and solidification agent is 0.5%-2% of the fly ash disposal amount.

4. The method for modifying municipal solid waste incineration fly ash as a promoter for clean incineration of municipal solid waste according to claim 1 or 2, characterized in that, The auxiliary carbonaceous raw material is carbon-containing solid waste or carbon-containing inferior resources, and the usage amount of the auxiliary carbonaceous raw material is less than 70% of the fly ash disposal amount.

5. The method for modifying waste incineration fly ash to be a waste clean incineration promoter according to claim 3, wherein, The auxiliary carbonaceous raw material is carbon-containing solid waste or carbon-containing inferior resources, and the usage amount of the auxiliary carbonaceous raw material is less than 70% of the fly ash disposal amount.

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