Solid waste incineration device suitable for low-nitrogen combustion waste heat recovery

Abstract

The invention relates to the technical field of solid waste incineration, and discloses a solid waste incineration device suitable for low-nitrogen combustion waste heat recovery. The feeding hopper is communicated with the bottom of the hearth body; the two air inlets are both used for introducing secondary air, and the two air inlets are both formed in the side wall of the hearth body in a communicating mode; and the separator is fixedly mounted in the hearth body. According to the scheme, unburned gas and burning gas are separated and then mixed, secondary air is introduced in the mixing process, combustible gas can make contact with oxygen more fully for complete combustion, the gas flow path is reasonably arranged, the gas mixing effect is enhanced, the fuel utilization rate is effectively increased through the design, energy waste is reduced, and the combustion efficiency is improved. The whole heat efficiency and purification efficiency of the incinerator are improved, meanwhile, the final emission concentration of nitric oxide can be reduced, the environmental protection performance of the whole incineration system is remarkably improved, and the increasingly strict emission standard requirement can be better met.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste incineration, and particularly to a solid waste incineration device suitable for low-nitrogen combustion and waste heat recovery. Background Art

[0002] NO in the atmosphere X After dissolving in water, it will form nitric acid rain, which will cause extensive harm to the environment and huge economic losses, such as corroding buildings and industrial equipment, damaging open-air cultural relics, damaging the leaves of plants leading to forest death, killing fish and shrimp in lakes, destroying the soil composition resulting in crop reduction or even death, and drinking groundwater contaminated by acid compounds is harmful to the human body. Therefore, the most direct way to reduce nitrogen oxide emissions is to reduce the generation at the source. Therefore, improving the waste incinerator is the most direct way to solve the problem of ultra-high nitrogen oxide emissions. Summary of the Invention

[0003] The purpose of the present invention is to solve the deficiencies existing in the prior art, and to propose a solid waste incineration device suitable for low-nitrogen combustion and waste heat recovery.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A solid waste incineration device suitable for low-nitrogen combustion and waste heat recovery, comprising a furnace body; a feed hopper, which is connected and arranged at the bottom of the furnace body; two air inlets, both of which are used for introducing secondary air, and both of the air inlets are connected and arranged on the side walls of the furnace body; a partition member, which is used to improve the mixing effect between the secondary air and the gas generated by garbage incineration, and is fixedly installed inside the furnace body.

[0006] As a preferred technical solution of the present invention, the furnace body includes a first side wall and a second side wall, and the two air inlets are respectively connected and arranged on the first side wall and the second side wall.

[0007] As a preferred technical solution of the present invention, the bottom of the furnace body is inclined, and the bottom of the furnace body is sequentially divided from high to low into: a drying area: used for preheating the incoming garbage to achieve the purpose of dehydration and drying; a combustion area: filled with oxygen inside for garbage incineration; a burnout area: used for burning out the unburned carbon particles and ash residues carried out from the combustion area.

[0008] As a preferred technical solution of the present invention, the feed hopper is located at the highest position at the bottom of the furnace body.

[0009] As a preferred technical solution of the present invention, the partition member is located between the air inlet and the bottom of the furnace body, and there are channels between the first side wall and the second side wall and the partition member, and the channels are used for passing the gas generated by garbage incineration.

[0010] As a preferred technical solution of the present invention, the cross-section of the partition member is in a triangular structure, and one of the sharp corners of the partition member is located between the two air inlets.

[0011] As a preferred technical solution of the present invention, the partition member is a water-cooled wall structure.

[0012] As a preferred technical solution of the present invention, water-cooled walls are provided on the inner sides of the first side wall and the second side wall, and the water-cooled walls are used to recover the combustion waste heat.

[0013] As a preferred technical solution of the present invention, a first channel is provided between the partition member and the first side wall, the first channel is located above the drying area, a second channel is provided between the partition member and the second side wall, and the second channel is jointly located above the combustion area and the burnout area.

[0014] A use method of a solid waste incineration device suitable for low-nitrogen combustion waste heat recovery, based on the solid waste incineration device suitable for low-nitrogen combustion waste heat recovery described in any one of the above, includes the following steps: Step 1: The garbage is dried in the drying area to generate unburned gas, and the unburned gas enters the first channel and moves upward; Step 2: The dried garbage enters the combustion area and the burnout area for incineration to generate combustion gas, and the generated combustion gas enters the second channel and moves upward; Step 3: Secondary air is introduced into the air inlets; Step 4: Under the guiding action of the partition member, the unburned gas and the combustion gas collide in the upper area of the partition member, and at the same time are mixed with the secondary air, and the three react with each other to reduce the emission of pollutants.

[0015] The present invention has the following beneficial effects:

[0016] 1. Improve combustion efficiency: In this solution, the unburned gas and the combustion gas are first separated and then mixed, and secondary air is introduced during the mixing process, so that the combustible gas can more fully contact oxygen for complete combustion. By reasonably arranging the air flow path, the mixing effect between gases is enhanced. This design effectively improves the utilization rate of fuel, reduces energy waste, and improves the overall thermal efficiency and purification efficiency of the incinerator;

[0017] 2. Reduce the emission of nitrogen oxides: The cooling effect of the partition member with a water-cooled wall structure helps to inhibit the formation of high-temperature regions, thereby reducing the generation of thermal nitrogen oxides. At the same time, ammonia acts as a reducing agent and undergoes a selective non-catalytic reduction reaction with nitrogen oxides in the mixing zone to convert them into harmless nitrogen and water vapor, further reducing the final emission concentration of nitrogen oxides. The environmental protection performance of the entire incineration system is significantly enhanced, and it can better meet the increasingly strict emission standard requirements;

[0018] 3. Improve the temperature distribution in the furnace: The presence of the water-cooled wall can absorb a large amount of heat, prevent local overheating, and thus achieve a uniform temperature distribution inside the furnace. This good temperature control helps maintain a stable combustion state, avoid equipment damage or unstable combustion caused by temperature fluctuations, and at the same time protect the furnace wall from direct high-temperature radiation and chemical corrosion, thereby delaying the aging of refractory materials, extending the overall service life of the incinerator, and reducing the maintenance frequency and cost. Brief Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions in the embodiments of this specification, the drawings required for the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of this specification, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 It is a schematic structural diagram of an incinerator in the prior art;

[0021] Figure 2 It is a schematic structural diagram of a solid waste incineration device suitable for low-nitrogen combustion and waste heat recovery proposed by the present invention.

[0022] In the figure: 1 furnace body, 11 side wall one, 12 side wall two, 13 drying area, 14 combustion area, 15 burnout area, 2 feed hopper, 3 water-cooled wall, 4 partition member, 41 passage one, 42 passage two, 5 air inlet. Detailed Embodiments

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments.

[0024] Before introducing the technical solutions described in this specification, the structure and working principle of the solid waste incineration device in the prior art will be briefly introduced:

[0025] Please refer to the attached Figure 1 , in the prior art, the waste incinerator consists of a furnace a and a feed hopper b. The furnace a is composed of front and rear arches and side walls on both sides. According to the waste incineration situation, the bottom of the furnace a is divided into different areas, namely area one c, area two d, and area three e. The waste is initially dehydrated at the position of area one c, area two d is the main incineration site, and the residual substances are burned out in area three e. Two air vents f are provided on the side wall of the furnace a for introducing secondary air. One air vent f is located above area one c, and the other air vent f is located above area two d and area three e. After the nitrogen-containing waste enters the furnace from the feed hopper b, it is incinerated through the three areas in sequence, and the generated gases are different;

[0026] Specifically, mixed gas one is generated in part of area one c and area two d. Since the garbage burns insufficiently in this part of the area and there is not enough oxygen to completely oxidize all carbon-containing substances into carbon dioxide, carbon monoxide (CO) will be produced. Secondly, during the incineration of waste containing moisture or other compounds that can decompose to produce hydrogen, hydrogen (H2) may be generated. Additionally, nitrogen-containing waste is not completely oxidized to nitrogen oxides (NO X ), and the retention of by-products in the selective non-catalytic reduction (SNCR) process may release ammonia (NH3). Therefore, mixed gas one includes, but is not limited to, CO, H2, and NH3; while in other areas of area two d and area three e, mixed gas two is generated. Since the nitrogen-containing garbage burns sufficiently in this part of the area, carbon dioxide (CO2) and NO X will be produced. Secondly, an excessive amount of oxygen (O2) needs to be introduced into this part of the area to supply sufficient combustion of the garbage. Therefore, mixed gas two includes, but is not limited to, CO2, NO X and O2;

[0027] Mixed gas one moves upward along the front wall of the furnace a, and mixed gas two moves upward along the rear wall of the furnace a. After the two contact and burn with the secondary air in the vent f respectively and are discharged. Such a design has some problems:

[0028] The combustible components in mixed gas one, such as CO and H2, need to contact oxygen sufficiently to burn completely. If these gases directly contact the secondary air without being fully mixed with other combustion products, it may cause some combustible gases not to contact enough oxygen for combustion, thereby reducing the overall combustion efficiency;

[0029] Since CO fails to burn completely and is converted into carbon dioxide, it will lead to an increase in CO emissions. Secondly, NH3 itself is a reducing agent and can be used to reduce NOx emissions under appropriate conditions. If NH3 is discharged from the system without fully reacting with NOx, not only will it lose its role as a reducing agent, but it may also be directly discharged into the atmosphere, becoming another pollutant source. Moreover, if there is a locally oxygen-deficient area, it may also promote the generation of more NOx. Therefore, the pollutants in the exhaust gas will increase, and it may be difficult to meet the increasingly strict environmental protection regulations.

[0030] In summary, the incinerators in the existing technologies have problems of low treatment efficiency and increased pollutant emissions in dealing with the incineration of nitrogen-containing garbage.

[0031] For this reason, please refer to the appendix Figure 2, the present invention provides a solid waste incineration device suitable for low-nitrogen combustion waste heat recovery, including a furnace body 1 and a feed hopper 2. Among them, the furnace body 1 is composed of front and rear arches, side wall one 11 and side wall two 12, which are made of refractory bricks, refractory castables, etc. Water-cooled walls 3 are provided on both side wall one 11 and side wall two 12. The bottom of the furnace body 1 is inclined to facilitate the movement of ash and slag towards the collection port. The bottom of the furnace body 1 is divided into a drying area 13, a combustion area 14, and a burnout area 15 from high to low in sequence. The feed hopper 2 is connected to the highest part of the bottom of the furnace body 1. Garbage enters from the feed hopper 2 and passes through these three areas in sequence. Air inlets 5 are provided on both side wall one 11 and side wall two 12 for introducing secondary air. The air inlets 5 are horizontally arranged so that the secondary air can fully impact and mix with the upward-moving gas generated by incineration. Commonly, the secondary air is air, which is used to provide combustion conditions such as oxygen for the gas generated at the bottom of the furnace body 1;

[0032] Furthermore, a partition member 4 is provided inside the furnace body 1 to improve the mixing effect between the secondary air and the gas generated by garbage incineration. The partition member 4 is located between the air inlet 5 and the combustion area 14. There are channels between both side wall one 11 and side wall two 12 and the partition member 4, and the channels are used to pass the gas generated by garbage incineration;

[0033] Furthermore, the cross-section of the partition member 4 is in a triangular structure, and each corner is in an arc-shaped structure. There is a channel one 41 between the partition member 4 and side wall one 11, and the channel one 41 is located above the drying area 13. There is a channel two 42 between the partition member 4 and side wall two 12, and the channel two 42 is commonly located above the combustion area 14 and the burnout area 15. It is worth mentioning that the flow range of the channel one 41 is larger than that of the channel two 42;

[0034] Furthermore, the partition member 4 is a water-cooled wall structure. Specifically, it includes but is not limited to a membrane water-cooled wall structure. Under the action of the partition member 4, unburned gases such as CO, H2, and NH3 generated in the drying area 13 and part of the combustion area 14 move upward into the furnace body 1 through the channel one 41. Combustion gases such as CO2, NO X and excess O2 in other areas of the combustion area 14 and the burnout area 15 will move upward through the channel two 42. In addition, the partition member 4 can reduce the temperature inside the furnace body 1. NO X mainly includes nitric oxide (NO) and nitrogen dioxide (NO2), which are mainly generated by the reaction of nitrogen (N2) and oxygen (O2) in the air under high-temperature conditions, especially more significantly when the temperature exceeds 1300 °C. The water-cooled wall can effectively absorb the heat released during the combustion process, thereby reducing thermal NO XThe generation is such that one of the pointed corners of the partition member 4 is located between the two air inlets 5, which plays a guiding role and helps the gas to be fully mixed with the secondary air after cooling. Specifically, when the three meet above the partition member 4, the chemical reactions involved include but are not limited to:

[0035] CO + 0.5O2 → CO2;

[0036] H2 + 0.5O2 → H2O;

[0037] 4NH3 + 5O2 → 4NO + 6H2O;

[0038] 4NH3 + 4NO + O2 → 4N2 + 6H2O;

[0039] 2NO + O2 → 2NO2;

[0040] 4NH3 + 2NO2 + O2 → 3N2 + 6H2O;

[0041] Among them, the generated H2O is in the form of water vapor in the high-temperature environment of the incinerator. In addition, if there are a small amount of volatile organic compounds (VOCs) in the unburned gas, this substance will also burn completely under oxygen conditions:

[0042] CxHy + (x + y / 4)O2 → xCO2 + (y / 2)H2O;

[0043] It can be seen from this that the full mixing of the unburned gas, the combustion gas and the secondary air, as well as the temperature reduction effect of the partition member 4, helps to reduce pollutant emissions.

[0044] The specific working principle of the present invention is as follows: After the low-nitrogen combustion waste enters the furnace body 1 from the feed hopper 2, it is dried in the drying area 13 to generate unburned gas. The unburned gas moves upward in the passage 41. The waste passing through the drying area 13 enters the combustion area 14 and the burnout area 15, and then is incinerated in the combustion area 14 and the burnout area 15 to generate combustion gas. The high-speed gas is formed through the passage 42. Under the guiding action of the partition member 4 and the temperature reduction effect of the partition member 4 and the water-cooled wall 3, the unburned gas and the combustion gas collide above the partition member 4, and then are fully mixed. At the same time, secondary air is sprayed into the furnace body 1 through the air inlet 5. The three are mixed and fully react. This design helps to achieve more efficient and clean combustion. It not only makes full use of the residual oxygen in the combustion gas to promote the complete combustion of the unburned gas, improves the combustion efficiency, but also promotes the mixing of the secondary air and the flue gas through the partition member 4, increases the area of waste heat recovery in the furnace, reduces the temperature at the combustion position, reduces the generation of incomplete combustion products and nitrogen oxides, thereby effectively reducing pollutant emissions and enhancing the environmental protection and energy utilization rate of the incineration process.

[0045] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, making equivalent replacements or changes should be covered within the protection scope of the present invention.

Claims

1. A solid waste incineration device applicable to low-nitrogen combustion waste heat recovery, comprising a furnace body (1) and a feed hopper (2), wherein the feed hopper (2) is communicatively arranged at the bottom of the furnace body (1), and is characterized in that, It also includes: Two air inlets (5), both for introducing secondary air, and both of the two air inlets (5) are connected and arranged on the side wall of the furnace body (1); A partition member (4) for improving the mixing effect between the secondary air and the gas generated by waste incineration, and the partition member (4) is fixedly installed inside the furnace body (1).

2. The solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 1, characterized in that, The furnace body (1) includes a first side wall (11) and a second side wall (12), and the two air inlets (5) are respectively connected and arranged on the first side wall (11) and the second side wall (12).

3. A solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 2, characterized in that, The bottom of the furnace body (1) is inclined, and the bottom of the furnace body (1) is sequentially divided from high to low into: A drying area (13) for preliminarily heating the waste entering the furnace to achieve the purpose of dehydration and drying; A combustion area (14) filled with oxygen for waste incineration; An afterburning area (15) for burning out the unburned carbon particles and ash residues carried out from the combustion area (14).

4. The solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 3, characterized in that, The feed hopper (2) is located at the highest position at the bottom of the furnace body (1).

5. The solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 4, characterized in that, [[ID=...]]The partition member (4) is located between the air inlet (5) and the bottom of the furnace body (1), and there are channels between the first side wall (11) and the second side wall (12) and the partition member (4), and the channels are used for passing the gas generated by waste incineration.

6. The solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 5, characterized in that, The cross-section of the partition member (4) is in a triangular structure, and one of the sharp corners of the partition member (4) is located between the two air inlets (5).

7. The solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 6, characterized in that, The partition member (4) is a water-cooled wall structure.

8. A solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 7, characterized in that, Water-cooled walls (3) are provided on the inner sides of the first side wall (11) and the second side wall (12), and the water-cooled walls (3) are used for recovering combustion waste heat.

9. The solid waste incineration device applicable to low-nitrogen combustion waste heat recovery according to claim 8, characterized in that, A first channel (41) is provided between the partition member (4) and the first side wall (11), and the first channel (41) is located above the drying area (13). A second channel (42) is provided between the partition member (4) and the second side wall (12), and the second channel (42) is jointly located above the combustion area (14) and the afterburning area (15).

10. A method for using a solid waste incineration device suitable for low-nitrogen combustion waste heat recovery, based on the solid waste incineration device suitable for low-nitrogen combustion waste heat recovery according to any one of claims 1-9, characterized in that, It includes the following steps: Step 1: The waste is dried in the drying area (13) to generate unburned gas, and the unburned gas enters the first channel (41) and moves upward; Step 2: The dried waste enters the combustion area (14) and the afterburning area (15) for incineration to generate combustion gas, and the generated combustion gas enters the second channel (42) and moves upward; Step 3: Secondary air is introduced into the air inlet (5); Step 4: Under the guiding action of the partition member (4), the unburned gas and the combustion gas collide in the upper area of the partition member (4), and at the same time are mixed with the secondary air, and the three react with each other to reduce pollutant emissions. It should be noted that in the provided content, there is an incomplete tag in ID=9 in the original Chinese text. The translated text retains the original structure and content as much as possible while making the translation conform to English expression habits. If there are any inaccuracies, please let me know according to the actual situation.

Images