A swirl combustion melting furnace

Abstract

The present application relates to the technical field of hazardous waste disposal, and discloses a swirl combustion melting furnace, comprising: a melting furnace body, the bottom of which has a melting furnace outlet; a plurality of nozzles arranged on the side wall of the melting furnace body for conveying air, fuel and ash to the inside of the melting furnace body, each nozzle penetrating the side wall, and one end of the nozzle extending into the inside of the melting furnace body; wherein each nozzle is located in the same plane and evenly distributed along a circumference centered on the center line of the melting furnace body, and the center line of each nozzle is eccentrically arranged with the center line of the melting furnace body, so that the gas ejected from each nozzle forms a swirl inside the melting furnace body that surrounds the center line of the melting furnace body and along the inner surface of the side wall. The swirl combustion melting furnace disclosed in the present application can not only effectively solve the problem of removing organic impurities in the ash disposal process, but also reduce the energy consumption of ash disposal.

Description

Technical Field

[0001] The present application relates to the technical field of hazardous waste disposal, and in particular to a swirl combustion melting furnace. Background Art

[0002] With the rapid development of my country's national economy, the amount of solid waste such as domestic garbage and medical waste has increased rapidly. These solid wastes are generally treated through landfill and incineration. Among them, landfill not only occupies a large amount of land, but also easily causes damage to the environment. Incineration can effectively reduce the toxicity of these wastes and is an effective method of solid waste disposal.

[0003] However, after incineration, solid waste will form ash residues rich in harmful substances such as dioxins and heavy metal ions, which are hazardous wastes. The traditional method is to dispose of these ash residues by landfill after chelation solidification, which has high disposal costs and the risk of secondary pollution to the environment. Therefore, how to remove organic matter from waste residues at low cost and effectively is a problem that technicians in this field need to solve. Summary of the invention

[0004] The present invention provides a swirl combustion melting furnace, which can effectively solve the problem of removing organic impurities in the ash disposal process and reduce the energy consumption of ash disposal.

[0005] In order to achieve the above object, the present invention provides a swirl combustion melting furnace, comprising:

[0006] A melting furnace body, wherein the bottom of the melting furnace body is provided with a melting furnace outlet;

[0007] A plurality of nozzles for conveying air, fuel and ash to the interior of the melting furnace body are arranged on the side wall of the melting furnace body, each of the nozzles penetrates the side wall, and one end of the nozzle extends into the interior of the melting furnace body; wherein the nozzles are located in the same plane and are evenly distributed along a circle centered on the center line of the melting furnace body, and the center line of each nozzle is eccentrically arranged between the center line of the melting furnace body, so that the gas ejected from each nozzle forms a vortex inside the melting furnace body that surrounds the center line of the melting furnace body and along the inner surface of the side wall.

[0008] The above-mentioned swirl combustion melting furnace includes a melting furnace body, and a plurality of nozzles are arranged on the side wall of the furnace body. The plurality of nozzles are located in the same plane and are evenly distributed along the circumference with the center line of the melting furnace body as the center line, and each nozzle is eccentrically arranged so that the gas ejected from each nozzle can form a swirl along the inner surface of the side wall inside the melting furnace body. The working principle of the above-mentioned melting furnace is as follows: ash, air and fuel enter the melting furnace through the nozzle, and the fuel and air form high-temperature gas after combustion. After the ash and the high-temperature gas exchange heat, they melt into small droplets. Since the gas ejected from each nozzle forms a swirl along the inner surface of the side wall in the melting furnace body, under the action of the swirl, the small droplets will adhere to the inner surface of the side wall during the downward swirl of the gas due to their own centrifugal force, and flow downward along the inner surface of the side wall under the action of their own gravity. At the same time, in the process of the small droplets flowing downward, the organic matter in the molten ash will undergo pyrolysis and oxidation, thereby removing the organic matter in the ash. Finally, the molten ash and flue gas leave the melting furnace from the melting furnace outlet at the bottom. In addition, during the removal process, the organic matter in the ash will burn with the combustion air to release heat, which can provide the heat required for the system operation, thereby effectively reducing the energy consumption of the ash disposal process.

[0009] Therefore, the swirl combustion melting furnace in the present invention can effectively remove organic matter in the ash that enters the furnace body through the nozzle by arranging evenly distributed nozzles on the side walls of the melting furnace body, and eccentrically arranging the center line of the nozzle and the center line of the furnace body. Due to the simple structure of the equipment, the cost of removing organic matter is reduced.

[0010] Preferably, the distance between the extended line of the center line of each nozzle and the center line of the melting furnace body is between 1 / 6 of the diameter of the melting furnace body and 1 / 3 of the diameter of the melting furnace body.

[0011] Preferably, it further comprises a plurality of protrusions arranged on the inner surface of the side wall and located between the nozzle and the outlet of the melting furnace.

[0012] Preferably, each of the protrusions is arranged along the circumference of the side wall of the melting furnace body.

[0013] Preferably, the protrusions are arranged at intervals, and the distance between every two adjacent protrusions is equal.

[0014] Preferably, the number of the nozzles is greater than or equal to 3.

[0015] Preferably, the nozzle comprises an inner channel for conveying fuel and an outer channel for conveying air and ash, the inner channel is a cylinder penetrating the nozzle, and the outer channel is an annular structure penetrating the nozzle and centered on the inner channel.

[0016] Preferably, it also includes a furnace nozzle inlet located on the top of the melting furnace body.

[0017] Preferably, it also includes a cooling device connected to the outlet of the melting furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the swirl combustion melting furnace in the present invention;

[0019] Figure 2 It is a schematic diagram of the plane structure of the nozzle in the present invention;

[0020] Figure 3 Schematic diagram of the nozzle head in the present invention.

[0021] In the figure:

[0022] 1- melting furnace body; 2- nozzle; 21- inner channel; 22- outer channel; 3- raised portion; 4- melting furnace outlet; 5- baking furnace nozzle inlet. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Please refer to Figure 1 as well as Figure 2 The present invention provides a swirl combustion melting furnace, comprising: a melting furnace body 1, the bottom of the melting furnace body 1 is provided with a melting furnace outlet 4; a plurality of nozzles 2 are arranged on the side wall of the melting furnace body 1, and the nozzles 2 are used to transport air, fuel and ash to the inside of the melting furnace body 1, and each nozzle 2 penetrates the side wall of the melting furnace body 1, and one end of the nozzle 2 extends into the inside of the melting furnace body 1. Among them, each nozzle 2 is located in the same plane and is evenly distributed along a circumference centered on the center line of the melting furnace body 1, and the center line of each nozzle 2 is eccentrically arranged with respect to the center line of the melting furnace body 1, so that the gas ejected from each nozzle 2 forms a swirl flow around the center line of the melting furnace body 1 and along the inner surface of the side wall inside the melting furnace body 1.

[0025] The above-mentioned swirl combustion melting furnace comprises a melting furnace body 1, and a plurality of nozzles 2 are arranged on the side wall of the furnace body. The plurality of nozzles 2 are located in the same plane and are evenly distributed along a circumference with the center line of the melting furnace body 1 as the center line, and each nozzle 2 is eccentrically arranged so that the gas ejected from each nozzle 2 can form a swirl along the inner surface of the side wall inside the melting furnace body 1. The working principle of the above-mentioned melting furnace is as follows: ash, air and fuel enter the melting furnace through the nozzle 2, and the fuel and air form high-temperature gas after combustion. After the ash and the high-temperature gas exchange heat, they melt into small droplets. Since the gas ejected from each nozzle 2 forms a swirl along the inner surface of the side wall in the melting furnace body 1, under the action of the swirl, the small droplets will adhere to the inner surface of the side wall due to their own centrifugal force during the downward swirl of the gas, and flow downward along the inner surface of the side wall under the action of their own gravity. At the same time, in the process of the small droplets flowing downward, the organic matter in the molten ash will undergo pyrolysis and oxidation, thereby removing the organic matter in the ash. Finally, the molten ash and flue gas leave the melting furnace from the bottom melting furnace outlet 4. In addition, during the removal process, the organic matter in the ash will burn with the combustion air to release heat, which can provide the heat required for the operation of the system, thereby effectively reducing the energy consumption of the ash disposal process.

[0026] The above-mentioned swirl combustion melting furnace is arranged eccentrically between the center line of the nozzle 2 and the center line of the melting furnace body 1, so that the gas ejected from each nozzle 2 forms a swirl inside the furnace body, so that the molten ash flows down along the inner surface of the side wall under the action of the swirl, and the organic matter in the molten ash undergoes pyrolysis and oxidation during the downward flow, so that the organic matter in the ash can be effectively removed. In addition, the above-mentioned melting furnace has a simple structure, low energy consumption per unit mass of ash treatment, and can maintain the stability of system operation.

[0027] It should be noted that after simple grinding, the ash enters the high-temperature environment of the melting furnace. Due to uneven heating inside the particles, it breaks into smaller particles. These fine particles can improve the heat transfer efficiency between the high-temperature combustion gases.

[0028] It should also be noted that the fuel used in the above-mentioned melting furnace can be natural gas, coke oven gas or other combustible gases.

[0029] For example, when the swirl combustion melting furnace in this application is used to establish a disposal center for treating ash from incineration of medical waste as the main component, the disposal scale is 5,000 tons / year, natural gas and air are used as fuel and combustion aid, and to ensure the effective melting of ash, the outlet flue gas temperature needs to be 1300° C. Since the organic matter in the ash can provide part of the energy required for ash disposal and the swirl melting furnace has a high energy utilization rate, the energy consumption per unit mass of ash disposal is 25% lower than that of the existing fuel-type melting furnace.

[0030] Alternatively, for example, when the swirl combustion melting furnace in the present application is used to establish a disposal center for treating ash from the incineration of domestic waste as the main component, the disposal scale is 10,000 tons / year, and natural gas and air are used as fuel and combustion aids. To ensure the effective melting of the ash, the outlet flue gas temperature needs to be 1250° C. Since the organic matter in the ash can provide part of the energy required for ash disposal and the swirl melting furnace has a high energy utilization rate, the energy consumption per unit mass of ash disposal is reduced by 30% compared with the existing fuel-type melting furnace.

[0031] Therefore, the swirl combustion melting furnace provided by the present invention can effectively remove organic matter from ash and slag while also effectively reducing energy consumption and saving costs.

[0032] In one embodiment, the distance between the extended line of the center line of each nozzle 2 and the center line of the melting furnace body 1 can be controlled to be between 1 / 6 of the diameter of the melting furnace body 1 and 1 / 3 of the diameter of the melting furnace body 1. Since each nozzle 2 is located in the same plane, not only can the airflows ejected from the nozzles 2 cooperate to generate a swirl, but the flame can also be prevented from directly scouring the refractory bricks, thereby effectively protecting the refractory bricks around the plane of the nozzle 2.

[0033] In order to increase the distance of the molten ash flowing down inside the furnace body, in one embodiment, a plurality of protrusions 3 may be provided on the inner surface of the side wall of the furnace body, and the protrusions 3 are located between the nozzle 2 and the melting furnace outlet 4. When the molten ash adheres to the inner surface of the side wall under its own centrifugal force and flows downward, the protrusions 3 increase the distance to the melting furnace outlet 4. In this process, the ion exchange inside the molten ash and the mass transfer effect between the molten ash and the high-temperature combustion gas may be increased, so that more organic matter in the ash is removed inside the melting furnace body 1, further reducing the organic matter content in the molten ash at the melting furnace outlet 4. In addition, the heavy metal ions in the ash may be evenly distributed in the ash.

[0034] It should be noted that, along the center line direction of the melting furnace body 1, the overall length of the protrusion is not limited. To a certain extent, the longer the overall length of the protrusion is, the better, so that more organic matter in the ash can be removed.

[0035] Specifically, each of the above-mentioned protrusions 3 may be arranged along the inner surface of the side wall of the melting furnace body 1, or may be a plurality of identical protrusions 3 within a range along the inner surface of the side wall. In one implementation, the plurality of protrusions 3 are arranged at intervals, and the distance between each two adjacent protrusions 3 is equal. It should be noted that the distance between each two adjacent protrusions 3 may be 0.

[0036] Generally speaking, the number of nozzles 2 in the present application is 3 or more, which can better form a swirl along the inner surface of the side wall. In one implementation, the number of nozzles 2 can be determined according to the diameter of the melting furnace. A conventional melting furnace can be provided with 4 nozzles 2, with an angle of 90 degrees between each adjacent two nozzles 2, and the gases ejected from the 4 nozzles 2 work together to produce a swirl; or, when the diameter of the melting furnace is larger, 6 nozzles 2 can be provided, with an angle of 60 degrees between each adjacent two nozzles 2, and the gases ejected from each nozzle 2 work together to produce a swirl.

[0037] It should be noted that the above limitation on the number of nozzles 2 is only an example, and other numbers may be selected in actual production applications.

[0038] In one embodiment, reference may be made to Figure 3 The nozzle 2 includes an outer channel 22 and an inner channel 21. The inner channel 21 is a cylindrical structure that runs through the nozzle 2, and the outer channel 22 is an annular channel structure that is centered on the inner channel 21 and surrounds the inner channel 21. The inner channel 21 is used to transport fuel to the inside of the melting furnace body 1, and the outer channel 22 is used to transport air and ash to the inside of the melting furnace body 1. Dividing the nozzle 2 into inner and outer channels 22 can facilitate separate control of the delivery amount of fuel and air for timely adjustment. In addition, a cooling water circulation jacket can be provided between the wall of the outer channel 22 and the wall of the nozzle 2 to cool the nozzle 2 and ensure long-term stable operation of the nozzle 2.

[0039] In this application, since the organic matter in the ash will release heat during the removal process by burning with the combustion air, and can also provide the heat required for the operation of the system, the energy consumption in the ash disposal process is reduced. The higher the organic matter content in the ash, the lower the actual natural gas consumption per unit ash disposal volume of the melting furnace in this application. Under some working conditions, the actual natural gas consumption per unit ash disposal volume can be as low as 60% to 70% of the natural gas consumption when the heat of combustion of organic matter is not considered, thereby effectively reducing energy consumption and saving costs.

[0040] The top of the melting furnace in the present invention is also provided with a furnace nozzle inlet 5, which can also spray a small amount of combustion-supporting air after the furnace is baked, thereby effectively protecting the refractory bricks on the top of the melting furnace body 1.

[0041] Since the present application adopts a flue gas downward movement solution, a cooling device connected to the melting furnace outlet 4 can also be arranged at the bottom of the melting furnace body 1. The molten ash enters the cooling device from the melting furnace outlet 4 and can form a glassy substance after cooling. The heavy metal ions form a form that is not easily leached in the glassy substance, thereby greatly reducing the leaching rate of the heavy metal ions, thereby achieving the goal of heavy metal solidification. The obtained glassy solid can be properly utilized as a paving material or a raw material for building materials.

[0042] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A swirl combustion melting furnace, characterized in that: include: A melting furnace body, wherein the bottom of the melting furnace body is provided with a melting furnace outlet; A plurality of nozzles for conveying air, fuel and ash to the interior of the melting furnace body are arranged on the side wall of the melting furnace body, each of the nozzles penetrates the side wall, and one end of the nozzle extends into the interior of the melting furnace body; wherein the nozzles are located in the same plane and are evenly distributed along a circle centered on the center line of the melting furnace body, and the center line of each nozzle is eccentrically arranged between the center line of the melting furnace body, so that the gas ejected from each nozzle forms a vortex inside the melting furnace body that surrounds the center line of the melting furnace body and along the inner surface of the side wall.

2. The swirl combustion melting furnace according to claim 1, characterized in that: The distance between the extended line of the center line of each nozzle and the center line of the melting furnace body is between 1 / 6 of the diameter of the melting furnace body and 1 / 3 of the diameter of the melting furnace body.

3. The swirl combustion melting furnace according to claim 1, characterized in that: It also includes a plurality of protrusions disposed on the inner surface of the side wall and located between the nozzle and the outlet of the melting furnace.

4. The swirl combustion melting furnace according to claim 3, characterized in that: Each of the protrusions is arranged along the circumference of the side wall of the melting furnace body.

5. The swirl combustion melting furnace according to claim 3 or 4, characterized in that: The protrusions are arranged at intervals, and the distance between every two adjacent protrusions is equal.

6. The swirl combustion melting furnace according to claim 1, characterized in that: The number of the nozzles is greater than or equal to 3.

7. The swirl combustion melting furnace according to claim 1, characterized in that: The nozzle comprises an inner channel for conveying fuel and an outer channel for conveying air and ash. The inner channel is a cylinder penetrating the nozzle, and the outer channel is an annular structure penetrating the nozzle and centered on the inner channel.

8. The swirl combustion melting furnace according to claim 1, characterized in that: It also includes a furnace nozzle inlet located on the top of the melting furnace body.

9. The swirl combustion melting furnace according to claim 1, characterized in that: Also included is a cooling device connected to the outlet of the melting furnace.

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