Small and medium-sized waste incinerator

Abstract

The utility model relates to a small and medium-sized garbage incinerator, relates to domestic waste incineration equipment field, including furnace body, the furnace body is in the inside is provided with the hearth, the settling chamber, the tail flue and the export flue who communicates from front to back in proper order, still be provided with fire grate, front arch and rear arch in the furnace body, front arch, rear arch set up in the top of fire grate, be equipped with the secondary air pipe on front arch and rear arch, be provided with the denitration spout in the stove and the stove temperature gauge on the furnace body at the hearth, the top of hearth is provided with primary atomization cooling device, be provided with air preheater, heat exchange device in the tail flue, the top of tail flue is provided with secondary atomization cooling, export flue leads out from the rear side of furnace body, the utility model structure is compact, can effectively carry out incineration environmental protection treatment to the garbage of the distribution more dispersed, low heat energy comprehensive utilization degree.

Description

Technical Field

[0001] This invention relates to the field of municipal solid waste incineration equipment, specifically a small to medium-sized waste incinerator. Background Technology

[0002] Waste incineration offers advantages such as small footprint, flexible site selection, short processing cycle, rapid and significant reduction in the volume of combustible waste, power generation from waste heat, and sterilization. However, it also has disadvantages including specific requirements for the calorific value of waste, high initial investment, and high operating costs. With the continuous development of the waste-to-energy industry, my country has largely completed the layout of large-scale waste-to-energy projects. However, a large portion of my country's population still resides in economically underdeveloped areas. Compared to economically developed regions, these areas have lower population densities, resulting in dispersed waste distribution, low thermal energy utilization, high transportation costs, lack of landfill space, and serious groundwater pollution issues. Furthermore, the cost of waste disposal in economically underdeveloped areas is significantly lower than in developed regions. Therefore, constructing large-scale waste-to-energy projects in underdeveloped areas does not necessarily bring good economic and social benefits. Thus, finding ways to reduce, harmlessly treat, and recycle waste in economically underdeveloped areas is a prerequisite for the sustainable development of comprehensive waste incineration. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a small to medium-sized waste incinerator that can incinerate waste that is relatively scattered and has a low degree of comprehensive utilization of thermal energy in an environmentally friendly manner.

[0004] The technical solution to achieve the above objectives is as follows: a small to medium-sized waste incinerator, comprising a furnace body, wherein a furnace chamber, a settling chamber, a tail flue, and an outlet flue are arranged sequentially from front to back within the furnace body; a grate is also provided within the furnace body; a front arch and a rear arch are provided on the furnace body; the front arch and the rear arch are both located above the grate, and secondary air ducts are provided on the front arch and the rear arch. The secondary air ducts are arranged in a tangential circular pattern, and the outlets of the secondary air ducts extend into the front arch and the rear arch and connect to the furnace chamber. The furnace chamber is located above the front arch and the rear arch, and the outlet flue is located on the rear side of the furnace body; the aforementioned... Small and medium-sized waste incinerators also include in-furnace denitrification nozzles, in-furnace temperature measuring holes, primary atomizing cooling devices, flue gas air preheaters, heat exchange devices, and secondary atomizing cooling devices. The in-furnace denitrification nozzles and in-furnace temperature measuring holes are located on the furnace body at corresponding locations in the furnace chamber, and thermometers are installed in the temperature measuring holes. The primary atomizing cooling device is located at the top of the furnace chamber, and the air preheater and heat exchange device are sequentially located in the tail flue. The secondary atomizing cooling device is located at the top of the tail flue. Both the primary and secondary atomizing cooling devices adopt an internal return water nozzle structure.

[0005] Furthermore, the tail flue is also equipped with a ventilation beam, which is connected to the low-temperature area of ​​the tail flue. The flue gas air preheater is suspended on the ventilation beam by a U-shaped hanging plate. An arc-shaped support plate is installed inside the U-shaped hanging plate and is connected to the U-shaped hanging plate. The arc-shaped support plate is used to support the air duct of the flue gas air preheater.

[0006] Furthermore, the tail flue is also provided with soot blowing holes, and soot blowers are connected to the soot blowing holes. The soot blowing holes are located above and below the flue gas air preheater.

[0007] Furthermore, the tube bundles of the air preheater are positioned using supporting steel plates.

[0008] Furthermore, the furnace body surrounding the furnace chamber, settling chamber, and tail flue is constructed with heavy brick furnace walls, and the top of the furnace chamber, as well as the front and rear arches, are constructed with corundum silicon carbide castable and lightweight insulating castable.

[0009] The beneficial effects of this invention are:

[0010] 1. In this invention, the flue gas from the waste fuel, after being sprayed by a primary atomizing cooling device in the furnace and passing through the settling chamber to reach the flue gas air preheater, has its temperature reduced to below 600°C. This prevents high-temperature corrosion of various components in the outlet flue gas. The secondary atomizing cooling device in the tail flue gas duct can directly reduce the flue gas temperature to around 200°C, thus preventing the regeneration of dioxins in the 300-400°C temperature range. Furthermore, the secondary atomizing cooling device can adjust the water spray volume according to the outlet flue gas temperature to achieve a reasonable exhaust temperature. To achieve the above technical effects, the atomizing cooling device of this invention employs an internal return water nozzle structure. The internal return water nozzle ensures both a sufficiently large water volume adjustment range and a good atomization effect. The counter-current mixing of water mist and flue gas allows for sufficient cooling of the high-temperature flue gas.

[0011] 2. The flue gas air preheater used in this invention can directly heat the air temperature to above 250°C, thereby ensuring that low-calorific-value waste is fully combusted and solving the problem of low-calorific-value waste being difficult to combust in economically underdeveloped areas.

[0012] 3. The flue gas air preheater of this invention employs a hanging device. The suspended ventilation beams are arranged in the low-temperature zone, ensuring the strength and rigidity of the beams and the entire hanging device. The U-shaped hanging plate of the hanging device incorporates an arc-shaped support plate, creating a segmented structure that effectively increases the stability of the hanging device. Therefore, the hanging device provided by this invention offers a high-strength, high-rigidity, and high-stability fixed structure solution for arranging heating surfaces in limited spaces in small and medium-sized waste incinerators. Furthermore, this invention also includes soot blowers at both the top and bottom of the flue gas air preheater, preventing ash accumulation on the tube bundles from affecting heat transfer and causing corrosion.

[0013] 4. The present invention also includes a heat exchange device in the tail flue. Heat users can selectively install the heat exchange device according to their actual needs. When there is a stable demand for heat, the heat exchange device is installed for heat supply; when there is no stable demand for heat, the device can be omitted.

[0014] 5. Except for the flue gas air preheater and heat exchange device, the entire boiler interior of this invention uses insulated furnace walls. In areas with unstable waste, if the amount of waste is too small to continue burning, the shutdown will have minimal impact on the corrosion of the boiler, thus ensuring the service life of the incinerator. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention;

[0016] Figure 2 for Figure 1 View from AA direction;

[0017] Figure 3 for Figure 1 A magnified view of part E;

[0018] Figure 4 for Figure 2 A magnified view of part of F;

[0019] Figure 5 for Figure 4 A magnified view of part of G;

[0020] Figure 6 This is a schematic diagram of the internal return water nozzle in this invention;

[0021] Figure 7 This is a schematic diagram of the structure in this invention, in which supporting steel plates are used for positioning between pipe groups. Detailed Implementation

[0022] The following embodiments are intended to illustrate the invention in more detail, but not to further limit the invention.

[0023] This invention discloses a small-to-medium-sized waste incinerator, which is used to incinerate waste that is relatively scattered and has a low degree of comprehensive utilization of thermal energy in an environmentally friendly manner.

[0024] like Figures 1 to 7 As shown, the present invention includes a furnace body 30 and a grate 1 within the furnace body 30. The furnace body 30 includes a front wall 31, a rear wall 32, left and right side walls 33, and a furnace top 34. A first partition wall 35 and a second partition wall 36 are provided between the front wall 31 and the rear wall 32. The front wall 31, the first partition wall 35, the left and right side walls 33, and the furnace top 33 form a furnace chamber 4. The first partition wall 35, the second partition wall 36, and the left and right side walls 33 form a settling chamber 5. The second partition wall 36... The rear wall 32, the left and right side walls 33 and the furnace top 34 form the tail flue 6. The upper part of the rear wall 32 is provided with the outlet flue 11. The furnace 4, the settling chamber 5, the tail flue 6 and the outlet flue 11 are arranged sequentially from front to back and connected. The front arch 2 is connected to the inner wall of the front wall 31. The first partition wall 35 is connected to the rear arch 3 on the side facing the front wall 31. The front arch 2 and the rear arch 3 are both set above the grate 1. The furnace 4 is located above the front arch 2 and the rear arch 3.

[0025] The present invention also includes an in-furnace denitrification nozzle 13, an in-furnace temperature measuring hole 14, a primary atomizing cooling device 7, a flue gas air preheater 8, a heat exchange device 9, and a secondary atomizing cooling device 10. The in-furnace denitrification nozzle 13 and the temperature measuring hole 14 are arranged on the left and right side walls 33 of the furnace 4 and are connected to the furnace 4. A thermometer is installed in the temperature measuring hole 14. The furnace 4 can use different SNCR nozzles to perform in-furnace denitrification according to the furnace temperature measured by the thermometer, so that the flue gas can be discharged in compliance with standards. A primary atomizing cooling device 7 is installed at the top of the furnace 4. An air preheater 8 and a heat exchanger 9 are sequentially installed inside the tail flue 6, with the heat exchanger 9 positioned above the air preheater 8. A secondary atomizing cooling device 10 is installed at the top of the tail flue 6. Both the primary atomizing cooling device 7 and the secondary atomizing cooling device 10 employ internal water return nozzles 12, used for counter-current mixing of water mist and flue gas to ensure sufficient cooling of the high-temperature flue gas. The internal water return nozzles are a previously disclosed design (Publication No.: CN86107184A). Figure 6As shown, the internal return water nozzle 12 includes an atomizing pipe 23, an inlet pipe 24, and a return water pipe 25. After the water enters through the return water pipe 25, part of it passes through the atomizing pipe 23 and is sprayed out from the nozzle, while the other part returns through the return water hole. The advantages of the internal return water nozzle 12 are large return water volume, small and adjustable spray water volume, and large coverage area, which can effectively control the temperature drop in the furnace body. The flue gas air preheater 8 draws in air from the air inlet, heats the air, and then injects it into the grate 1 through the air outlet to ensure that low-calorific-value waste is fully combusted. The flue gas air preheater 8 is implemented using existing publicly available technology and is a pipe group 21 composed of multiple sets of air ducts 22. The heat exchange device 9 is used to provide a heat source to the heat user and can be selected for installation according to actual needs. The tail flue 6 is also equipped with a ventilation beam 19, which connects to the low-temperature zone of the tail flue 6. The flue gas air preheater 8 is suspended from the ventilation beam 19 by a U-shaped hanging plate 18. An arc-shaped support plate 20 is installed inside the U-shaped hanging plate 18 and is connected to the U-shaped hanging plate 18. The arc-shaped support plate 20 is used to support the air duct 22 of the flue gas air preheater 8, so that the hanging plate 18 forms a segmented structure, thereby increasing the stability of the suspension. Except for the air duct gaps with arc-shaped support plates 20, the gaps of other air ducts 22 in the pipe group 21 of the flue gas air preheater 8 are all positioned by supporting steel plates 17. The tail flue 6 is equipped with soot blowing holes 16 at the top and bottom of the flue gas air preheater 8. Soot blowers are connected to the soot blowing holes to prevent soot from accumulating on the pipe group of the flue gas air preheater 8. The furnace body surrounding the furnace chamber 4, settling chamber 5 and tail flue 6 is constructed with heavy brick furnace walls. The top of the furnace chamber 4, the front arch 2 and the rear arch 3 are all constructed with corundum silicon carbide castable and lightweight heat-insulating castable. The above structures have good heat insulation effect.

[0026] After the waste fuel is burned on the grate 1, the flue gas is supplemented with secondary air through the throat formed by the front arch 2 and the rear arch 3 to achieve complete combustion. After being cooled in the furnace 4 and ash is collected in the settling chamber 5, it enters the tail flue 6. After absorbing heat through the flue gas air preheater 8 and the heat exchange device 9, it is cooled by atomization and discharged from the boiler through the outlet flue 11.

[0027] Secondary air ducts 15 arranged in a tangential circle are used on the front arch 2 and the rear arch 3. The outlets of the secondary air ducts extend into the front and rear arches and are connected to the furnace. The function of the secondary air ducts 15 is to supplement the oxygen required for suspension combustion, enhance flue gas turbulence, extend the travel distance of carbon particles in the furnace, and form an aerodynamic field to lock in the particles, thereby reducing fly ash emissions. In this embodiment, the primary atomizing cooling device 7 can reduce the temperature of the flue gas reaching the flue gas air preheater 8 through the settling chamber 5 to below 600°C, thereby avoiding high-temperature corrosion of various components in the tail flue duct 6 by the high-temperature flue gas. The secondary atomizing cooling device 10 can directly reduce the flue gas temperature to about 200°C, thereby avoiding the regeneration of dioxins in the temperature range of 300~400°C.

[0028] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A small to medium-sized waste incinerator, comprising a furnace body, wherein a furnace chamber, a settling chamber, a tail flue, and an outlet flue are arranged sequentially from front to back within the furnace body, and a grate is also provided within the furnace body, and a front arch and a rear arch are provided on the furnace body; characterized in that: The front and rear arches are both located above the grate. Secondary air ducts are provided on the front and rear arches. The secondary air ducts are arranged in a tangential circle. The air outlets of the secondary air ducts extend into the front and rear arches and are connected to the furnace. The furnace is located above the front and rear arches. The outlet flue is located on the rear side of the furnace body. The aforementioned small and medium-sized waste incinerator also includes an in-furnace denitrification nozzle, an in-furnace temperature measuring hole, a primary atomization cooling device, a flue gas air preheater, a heat exchange device, and a secondary atomization cooling device. The in-furnace denitrification nozzle and the in-furnace temperature measuring hole are both located on the furnace body at the corresponding location in the furnace chamber, and a thermometer is installed in the temperature measuring hole. The primary atomizing cooling device is located at the top of the furnace, the air preheater and heat exchanger are sequentially located in the tail flue, and the secondary atomizing cooling device is located at the top of the tail flue; both the primary and secondary atomizing cooling devices adopt an internal water return nozzle structure. After being sprayed by the primary atomizing cooling device in the furnace, the flue gas reaches the flue gas air preheater through the settling chamber, where the flue gas temperature drops below 600℃. This prevents high-temperature corrosion of various components in the outlet flue gas. The secondary atomizing cooling device in the tail flue gas duct can directly reduce the flue gas temperature to around 200℃, thus preventing the regeneration of dioxins in the 300-400℃ temperature range. Furthermore, the secondary atomizing cooling device can adjust the water spray volume according to the outlet flue gas temperature to achieve a reasonable exhaust temperature. The tail flue is also equipped with a ventilation beam, which is connected to the low-temperature area of ​​the tail flue. The flue gas air preheater is suspended on the ventilation beam by a U-shaped hanging plate. An arc-shaped support plate is installed inside the U-shaped hanging plate and is connected to the U-shaped hanging plate. The arc-shaped support plate is used to support the air duct of the flue gas air preheater.

2. A small-to-medium-sized waste incinerator according to claim 1, characterized in that: Soot blowing holes are provided on the tail flue above and below the flue gas air preheater, and each soot blowing hole is connected to a soot blower.

3. A small-to-medium-sized waste incinerator according to claim 1, characterized in that: The tube bundles of the air preheater are positioned using supporting steel plates.

4. A small-to-medium-sized waste incinerator according to claim 1, characterized in that: The furnace body, including the furnace chamber, settling chamber, and tail flue, is constructed with heavy brick walls. The top of the furnace chamber, as well as the front and rear arches, are constructed with corundum silicon carbide castable and lightweight insulating castable.

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