Method and device for processing household waste incineration slag

Abstract

The application discloses a household garbage incineration slag treatment method, which combines a ceramic carrier of a catalyst in a combustion chamber to decompose chlorophenol substances generated in an incineration process; when the incineration slag generated after incineration of the household garbage is cooled, activated carbon is added to adsorb dioxin gas; during the cooling process, blast furnace slag is added to the incineration slag, and the calcium element of the blast furnace slag is combined with the chlorine element of the incineration slag and removes the chlorine element through stirring, electrification and activation; the first particle size of particulate matters is cleaned through a cleaning liquid, and the cleaned solution is mixed with the second particle size of particulate matters and the bottom ash of the incineration slag to be cleaned in an ultrasonic vibration mode; the solution after the ultrasonic vibration cleaning is vibrated by carbon dioxide gas generated by combustion in the combustion chamber to form a precipitate and fix the carbon dioxide. The application further discloses a device. The technical scheme of the application can effectively and efficiently treat harmful substances of the incineration slag and reduce carbon dioxide emission.

Description

Technical Field

[0001] This invention relates to the field of municipal solid waste incineration ash treatment technology, and particularly to a method and apparatus for treating municipal solid waste incineration ash. Background Technology

[0002] Traditionally, large volumes of municipal solid waste are disposed of through direct landfill. However, this method requires excavating large landfills using valuable land resources, and lining the bottom of these landfills with leak-proof plastic material. Once the landfill reaches its maximum capacity, it needs to be sealed with a sealing material. Although the landfill is sealed, the waste inside continues to ferment and decompose. Wastewater from this fermentation seeps through leaks in the plastic material at the bottom and pollutes the groundwater. Furthermore, heavy metal contaminants can cause irreparable damage to the soil at the bottom.

[0003] To avoid the various problems caused by landfilling of municipal solid waste, high-temperature incineration is required. Although high-temperature incineration can effectively reduce the volume and weight of municipal solid waste, improper temperature control during the incineration process can lead to the incineration temperature not reaching the target value or incomplete combustion of some municipal solid waste, which can also produce a certain amount of pollutants, such as dioxins. Dioxins are organic carcinogens that can remain in the human body. Therefore, it is very important to treat municipal solid waste incineration ash with effective technical means to minimize the presence of harmful substances. Summary of the Invention

[0004] The main objective of this invention is to propose a method for treating municipal solid waste incinerator slag. This invention also proposes an apparatus for applying the method for treating municipal solid waste incinerator slag, aiming to efficiently treat the harmful substances in the incinerator slag and reduce carbon dioxide emissions.

[0005] To achieve the above objectives, the present invention proposes a method for treating municipal solid waste incineration ash, comprising the following steps:

[0006] Step S1: Place the ceramic carrier with catalyst in the combustion chamber to decompose the chlorophenols produced during the incineration process of municipal solid waste.

[0007] Step S2: When cooling the incinerator slag produced after municipal solid waste incineration, activated carbon is added to the incinerator slag to adsorb dioxin gas.

[0008] Step S3: During the continuous cooling process of municipal solid waste incinerator slag, blast furnace slag is added to the incinerator slag. Under the conditions of stirring, powering on and activation, the calcium element of the blast furnace slag combines with the chlorine element of the incinerator slag and removes the chlorine element.

[0009] Step S4: Sorting is performed according to different particle sizes, and the particles of the first size are cleaned with a cleaning solution. After cleaning, the solution is mixed with the particles of the second size and the bottom ash of the incinerator slag, and then vibrated and cleaned by ultrasonic vibration.

[0010] Step S5: After the solution has been cleaned by ultrasonic vibration, carbon dioxide gas generated by combustion in the combustion chamber is introduced into the solution to form a precipitate that is insoluble in water and to fix the carbon dioxide.

[0011] Preferably, the catalyst in step S1 is a mixture of ammonium molybdate and vanadium pentoxide in a 4:6 ratio, which is dissolved in distilled water by heating and stirring. The porous ceramic support is then immersed in the distilled water solution to allow the catalyst to fully penetrate the pores inside the porous ceramic support. The immersed ceramic support is then heated in an air atmosphere at 400-450 degrees Celsius for 6 hours.

[0012] Preferably, in step S3, the blast furnace slag and the incinerator slag are thoroughly mixed, and the chlorine element in the internal substances of the incinerator slag is removed by the symbiotic relationship between calcium oxide and silica in the blast furnace slag. A vibratory mill that is simultaneously powered and activated is used during the mixing process.

[0013] Preferably, in step S4, the particles with the first particle size are particles with a diameter of 0.15 mm or larger, and the particles with the second particle size are particles with a diameter of 0.15 mm or smaller.

[0014] Preferably, in step S5, calcium combines with carbon dioxide to form calcium carbonate, aluminum combines with carbon dioxide to form aluminum oxide, and calcium also combines with chlorine to form calcium chloride. Calcium carbonate, aluminum oxide, and calcium chloride are all precipitates that are difficult to dissolve in water.

[0015] The present invention also proposes an apparatus for applying the aforementioned method for treating municipal solid waste incinerator slag, comprising a combustion chamber, which includes a preheating zone, a pyrolysis zone, and a combustion zone arranged from top to bottom. The preheating zone and the pyrolysis zone are closed or opened by a first partition, and the pyrolysis zone and the combustion zone are closed or opened by a second partition. The middle part of the side of the pyrolysis zone is connected to the middle part of the combustion zone through a first pipeline, and the upper part of the combustion zone is connected to the upper part of the pyrolysis zone through a second pipeline.

[0016] Preferably, the top of the preheating zone is provided with a filling port, through which domestic waste is added into the preheating zone. The bottom of the combustion zone is provided with a discharge port, which is connected to a cooler via a pipeline. The outlet of the cooler is connected to a separator, which can separate the domestic waste incineration slag and metal materials. The side of the preheating zone is connected to a dust collector and an acid gas remover in sequence via a third pipeline.

[0017] The technical solution of this invention has the following advantages over the prior art:

[0018] This invention incorporates a catalyst-containing ceramic carrier within the combustion chamber to decompose chlorophenols generated during the incineration process of municipal solid waste, preventing the formation of dioxins. Additionally, activated carbon absorbs dioxins from the incinerator slag during the cooling process. Furthermore, blast furnace slag is added during the slag crushing process, and under stirring, electrification, and activation conditions, the calcium in the blast furnace slag combines with and removes the chlorine from the incinerator slag. Finally, particles are sorted according to their size, and the first-size particles are washed with a cleaning solution. The resulting solution is then mixed with the second-size particles and the bottom ash of the incinerator slag and subjected to ultrasonic vibration cleaning. Carbon dioxide gas generated during combustion in the combustion chamber is introduced into the ultrasonically cleaned solution, forming a water-insoluble precipitate and fixing the carbon dioxide. Therefore, this invention achieves efficient treatment of harmful substances in incinerator slag and reduces carbon dioxide emissions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1 This is a flowchart of the method for treating municipal solid waste incineration slag according to the present invention;

[0021] Figure 2 This is a schematic diagram of the device of the present invention.

[0022] Explanation of icon numbers:

[0023] 1. Combustion chamber; 11. Preheating zone; 12. Pyrolysis zone; 13. Combustion zone; 14. Discharge port; 15. Filling port; 16. First baffle; 17. Second baffle; 18. First pipeline; 19. Second pipeline; 110. Third pipeline; 2. Cooler; 3. Separator; 4. Dust collector; 5. Acid gas removal device.

[0024] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] This invention proposes a method for treating municipal solid waste incineration slag.

[0027] Please see Figure 1 The method for treating municipal solid waste incinerator slag according to an embodiment of the present invention includes the following steps:

[0028] Step S1: Place the ceramic carrier with catalyst in the combustion chamber to decompose the chlorophenols produced during the incineration process of municipal solid waste.

[0029] Step S2: When cooling the incinerator slag produced after municipal solid waste incineration, activated carbon is added to the incinerator slag to adsorb dioxin gas.

[0030] Step S3: During the continuous cooling process of municipal solid waste incinerator slag, blast furnace slag is added to the incinerator slag. Under the conditions of stirring, powering on and activation, the calcium element of the blast furnace slag combines with the chlorine element of the incinerator slag and removes the chlorine element.

[0031] Step S4: Sorting is performed according to different particle sizes, and the particles of the first size are cleaned with cleaning solution. After cleaning, the solution is mixed with the particles of the second size and the bottom ash, and then vibrated and cleaned by ultrasonic vibration.

[0032] Step S5: After the solution has been cleaned by ultrasonic vibration, carbon dioxide gas generated by combustion in the combustion chamber is introduced into the solution to form a precipitate that is insoluble in water and to fix the carbon dioxide.

[0033] In step S1 of this embodiment, by attaching the catalyst to the inner wall of the combustion chamber, the dioxin harmful gas and the corresponding chlorophenol material generated during the high-temperature incineration of municipal solid waste are decomposed.

[0034] Preferably, the catalyst in this embodiment is formed by mixing ammonium molybdate and vanadium pentoxide in a 4:6 ratio, and dissolved in distilled water by heating and stirring. A porous ceramic support is then immersed in the distilled water for a certain period, allowing the catalyst to fully penetrate the porous ceramic support's internal pores. The immersed ceramic support is then heated in an air atmosphere at 400-450 degrees Celsius for 6 hours, thereby fixing the catalyst within the ceramic support's internal pores. It should be noted that the heating temperature of the catalyst-immersed ceramic support must be within the 400-450 degrees Celsius range. If the heating temperature is below 400 degrees Celsius, the catalyst cannot be reliably fixed to the ceramic support; if the heating temperature is above 450 degrees Celsius, the catalyst and ceramic support will separate.

[0035] Since dioxins generated from the incineration of municipal solid waste are mainly produced by chlorophenols, the production of chlorophenols during the incineration process can be suppressed by placing the aforementioned ceramic carrier with catalyst on the inner wall of the incinerator. This allows for the decomposition of dioxins generated from chlorophenols during the high-temperature incineration stage.

[0036] In step S2 of this embodiment, after municipal solid waste is incinerated at high temperature and becomes incinerator slag, the incinerator slag is transferred to other work stations. Since the municipal solid waste incinerator slag still has a certain amount of residual heat, activated carbon is added to the municipal solid waste incinerator slag to absorb the dioxin gas remaining in the incinerator slag.

[0037] Preferably, the activated carbon in this embodiment of the invention is produced using chemical reagents such as zinc chloride or phosphoric acid as activators, through the treatment of materials such as wood, lignite, and peat. Therefore, the activated carbon obtained above can absorb and treat dioxin gases produced by municipal solid waste incineration slag during the insulation stage. Furthermore, in this embodiment of the invention, 0.5 kg of activated carbon is applied per ton of municipal solid waste incineration slag, and the temperature when adding activated carbon to the slag must not exceed the ignition temperature of the activated carbon, 450 degrees Celsius. When injecting the activated carbon, a funnel-shaped or screw feeder is used, and an air compressor and injection nozzles are used to add activated carbon powder to the incineration slag.

[0038] In step S3 of this embodiment, during the pig iron production process, raw materials such as iron ore, coke, and limestone are injected into the blast furnace to smelt iron. The by-product of pig iron production is blast furnace slag. In this embodiment of the invention, the municipal solid waste incineration slag is partially caking. It is crushed by means of crushing, and blast furnace slag is added during the crushing process to introduce calcium oxide. Furthermore, to ensure thorough mixing of the blast furnace slag and the incineration slag, and to remove chloride ions from the incineration slag through the calcium oxide in the blast furnace slag, this embodiment of the invention uses a vibratory mill capable of simultaneous electrification and activation.

[0039] In the existing technology, quicklime (CaO) is usually added during the dechlorination treatment of compounds so that the quicklime can combine with the active chlorine released from the compound. Since quicklime is an amorphous material with strong Ca=O bonds and requires a lot of heat to activate.

[0040] In the blast furnace slag material added in this embodiment of the invention, the Ca element exists in the forms of -Ca-Si and -Ca-O-Si. Therefore, the energy required for activation through pulverization is relatively low. Furthermore, Ca atoms exist in the -Si-O network, generating a wavefront that can be obtained through physical energy, making it easy for active calcium to be expressed on the surface. Although the CaO component is bonded to SiO2, CaO does not simply absorb moisture to form Ca(OH)2.

[0041] Because chlorine-containing substances in incinerator slag can generate dioxins within a certain temperature range during the continuous cooling process, this invention addresses this issue by directly mixing blast furnace slag with incinerator slag during the cooling stage, and under the combined conditions of electricity and activation, allowing calcium and chlorine elements to combine and form calcium chloride precipitate. This removes chlorine from the incinerator slag, thus preventing the generation of dioxins during the continuous cooling process.

[0042] In step S4 of this embodiment, the screening and separation method adopted in this embodiment of the invention involves pre-removing ferrous metals using a magnetic separator. This magnetic separator separates substances using magnetic force, and a cyclone separator separates and collects incinerator ash and particles smaller than 0.15 mm. In the magnetic separator, incinerator ash and ferrous metal particles are separated, while in the cyclone separator, particles larger than 0.15 mm are separated from substances smaller than 0.15 mm by a rotor, and the particles are stored in corresponding storage containers.

[0043] Next, the particles larger than 0.15 mm are washed with distilled water with a pH of 5-7. The washing solution after the initial washing is then mixed with incinerator ash and particles smaller than 0.15 mm. Ultrasonic waves are used to vibrate the container of the solution, so that chlorides are separated from the ash and particles and dissolved in the water. In addition, the amount of water and the intensity and duration of ultrasonic waves can be adjusted according to different particle sizes or stepped particle sizes.

[0044] In step S5 of this embodiment, carbon dioxide produced by the combustion of a solution containing chloride is introduced into the combustion chamber after ultrasonic vibration. This causes calcium to combine with carbon dioxide to form calcium carbonate, aluminum to combine with carbon dioxide to form aluminum oxide, and calcium to combine with chlorine to form calcium chloride. The calcium carbonate, aluminum oxide, and calcium chloride are all precipitates that are difficult to dissolve in water. Finally, the precipitates are separated from the water by filtration, and the carbon dioxide is fixed.

[0045] Please see Figure 2 The present invention also proposes an apparatus for incinerating municipal solid waste slag, comprising a combustion chamber 1. The combustion chamber 1 includes a preheating zone 11, a pyrolysis zone 12, and a combustion zone 13 arranged from top to bottom. The preheating zone 11 and the pyrolysis zone 12 are connected by a first partition 16, which closes or opens the connection. The pyrolysis zone 12 and the combustion zone 13 are connected by a second partition 17, which closes or opens the connection. The middle part of the side of the pyrolysis zone 12 is connected to the middle part of the combustion zone 13 via a first pipe 18, and the upper part of the combustion zone 13 is connected to the upper part of the pyrolysis zone 12 via a second pipe 19.

[0046] The preheating zone 11 is used to temporarily store municipal solid waste. Heat from the pyrolysis zone 12 is transferred to the preheating zone 11 through a first partition, preheating and drying the municipal solid waste. The pyrolysis zone 12 receives high-temperature air from the combustion zone 13 to decompose the dried municipal solid waste at high temperatures, causing initial melting and generating carbon monoxide gas. The generated carbon monoxide gas is then transported to the combustion zone 13 to aid combustion. Furthermore, the ceramic carrier incorporating the catalyst is disposed on the inner wall of the combustion zone 13.

[0047] Additionally, a filling port 15 is provided at the top of the preheating zone, through which municipal solid waste can be added into the preheating zone 11. A discharge port 14 is provided at the bottom of the combustion zone 13, connected to the cooler 2 via a pipeline. The outlet of the cooler 2 is connected to the separator 3, which separates the municipal solid waste incineration slag and metal materials. Furthermore, the side of the combustion zone 13 is connected to a dust collector 4 and an acid gas remover 5 via a third pipeline 110 to collect and remove dust and acid gases.

[0048] The first, second, and third pipelines are each equipped with control valves.

[0049] Please see Figure 2 The working principle of the device for municipal solid waste incineration slag according to an embodiment of the present invention:

[0050] Domestic waste is added to the preheating zone 11 through the filling port 15. Since the pyrolysis zone 12 performs hot air pyrolysis treatment on the domestic waste, the heat of the pyrolysis zone 12 can be conducted from bottom to top to the preheating zone 11, thereby preheating the domestic waste.

[0051] After passing through the first partition 16, the domestic waste enters the pyrolysis zone 12. The heat and hot air generated by combustion in the combustion zone 13 are transferred to the pyrolysis zone 12 through the second pipeline 19 to pyrolyze the domestic waste. At this time, the control valve corresponding to the first pipeline 18 is closed.

[0052] After the municipal solid waste is pyrolyzed in the pyrolysis zone 12, the carbon monoxide gas produced after a certain period of time is transported to the combustion zone through the first pipeline 18 to assist combustion in the combustion zone 13. At this time, the control valve corresponding to the second pipeline 19 is closed, while the control valve corresponding to the first pipeline 18 is open.

[0053] After municipal solid waste is burned into incinerator slag in combustion zone 13, the gases produced during the combustion process are removed by dust collector 4 and acid gas remover 5. The incinerator slag is then transferred to cooler 2 through discharge port for cooling, and then passes through separator 3 to separate the bottom ash and metal materials of the incinerator slag.

[0054] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for treating municipal solid waste incineration slag, characterized in that, Includes the following steps: Step S1: Place the ceramic carrier with catalyst in the combustion chamber to decompose the chlorophenols produced during the incineration process of municipal solid waste. Step S2: When cooling the incinerator slag produced after municipal solid waste incineration, activated carbon is added to the incinerator slag to adsorb dioxin gas. Step S3: During the continuous cooling process of municipal solid waste incinerator slag, blast furnace slag is added to the incinerator slag. Under the conditions of stirring, powering on and activation, the calcium element of the blast furnace slag combines with the chlorine element of the incinerator slag and removes the chlorine element. Step S4: After removing ferrous metals from the incinerator slag using a magnetic separator, the slag is sorted according to different particle sizes. A cyclone separator is used to separate and collect particles of the first and second particle sizes. The particles of the first particle size are then washed with a washing solution. The washing solution is then mixed with the particles of the second particle size and the bottom ash of the incinerator slag, and the mixture is vibrated and washed using ultrasonic vibration. The particles of the first particle size are incinerator slag with a diameter of 0.15 mm or larger, and the particles of the second particle size are incinerator slag with a diameter of less than 0.15 mm. Step S5: After the solution has been cleaned by ultrasonic vibration, carbon dioxide gas generated by combustion in the combustion chamber is introduced into the solution to form a precipitate that is insoluble in water and to fix the carbon dioxide.

2. The method for treating municipal solid waste incinerator slag as described in claim 1, characterized in that, The catalyst in step S1 is a mixture of ammonium molybdate and vanadium pentoxide in a 4:6 ratio, which is dissolved in distilled water by heating and stirring. The porous ceramic support is then immersed in the distilled water solution to allow the catalyst to fully penetrate the pores inside the porous ceramic support. The immersed ceramic support is then heated in an air atmosphere at 400-450 degrees Celsius for 6 hours.

3. The method for treating municipal solid waste incinerator slag as described in claim 1, characterized in that, In step S3, blast furnace slag and incinerator slag are thoroughly mixed, and the chlorine element inside the incinerator slag is removed by the symbiotic relationship between calcium oxide and silica in the blast furnace slag. A vibrating mill that is simultaneously powered and activated is used during the mixing process.

4. The method for treating municipal solid waste incinerator slag as described in claim 1, characterized in that, In step S5, calcium combines with carbon dioxide to form calcium carbonate, aluminum combines with carbon dioxide to form aluminum oxide, and calcium also combines with chlorine to form calcium chloride. Calcium carbonate, aluminum oxide, and calcium chloride are all precipitates that are difficult to dissolve in water.

5. A combustion apparatus employing the method for treating municipal solid waste incinerator slag as described in any one of claims 1-4, characterized in that, It includes a combustion chamber, which comprises a preheating zone, a pyrolysis zone, and a combustion zone arranged from top to bottom. The preheating zone and the pyrolysis zone are closed or opened by a first partition, and the pyrolysis zone and the combustion zone are closed or opened by a second partition. The middle part of the side of the pyrolysis zone is connected to the middle part of the combustion zone through a first pipeline, and the upper part of the combustion zone is connected to the upper part of the pyrolysis zone through a second pipeline.

6. The combustion device as described in claim 5, characterized in that, The preheating zone is equipped with a filling port at the top, through which municipal solid waste is added to the preheating zone. The combustion zone is equipped with a discharge port at the bottom, which is connected to a cooler via a pipeline. The outlet of the cooler is connected to a separator, which can separate municipal solid waste incineration slag and metal materials. The side of the preheating zone is connected to a dust collector and an acid gas remover via a third pipeline.

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