An incinerator

Abstract

The present application provides a kind of incinerator, including annular air pipe, air supply main pipe, the air supply main pipe is equipped with first air pipe, second air pipe, third air pipe.The air distribution system for small-sized domestic waste pyrolysis gasification incinerator of the present application divides three-way air into different reaction zones of furnace to maintain garbage reaction by active delivery of air mixing combustion, actively controls flow field in furnace, and can actively control oxygen supply amount of corresponding area according to oxygen demand law of garbage in different reaction zones, which is beneficial to improve the stability of flow field in furnace, optimize the reaction process of garbage, reduce the external energy consumption of garbage and the heat loss of ash, improve the component stability of pyrolysis gas and the operation stability of secondary combustion chamber, facilitate further processing of pyrolysis gas, and create favorable conditions for incinerator to achieve better emission level.

Description

Technical Field

[0001] This invention relates to the field of municipal solid waste treatment technology, and in particular to an incinerator. Background Technology

[0002] Decentralized municipal solid waste incineration is a new trend in addressing urban and rural waste disposal, in addition to large-scale centralized incineration power generation, and serves as a necessary supplement to it. The key to developing decentralized municipal solid waste incineration is the mature technology of small-scale incinerators that strictly meet pollutant emission standards. Research has found that small-scale municipal solid waste incinerators based on pyrolysis incineration processes can achieve extremely low emission levels of important pollutants such as dioxins and carbon monoxide, demonstrating promising development prospects.

[0003] The core idea of ​​pyrolysis is to heat municipal solid waste in an anaerobic environment to cause a pyrolysis reaction, generating pyrolysis gas containing combustible components and environmentally harmless residue. The pyrolysis gas is then premixed and combusted with supplemental air to reach the ideal temperature. The high-temperature flue gas discharged after secondary combustion has a very low concentration of organic pollutants.

[0004] Since pyrolysis is an endothermic reaction with reducing properties, two conditions are required for waste to undergo pyrolysis: high temperature and an oxygen-free environment. High temperature means the waste must be heated, and there are two common heating methods: direct heating and indirect heating. Direct heating involves direct contact and heat exchange between the high-temperature working fluid and the waste; the working fluid flows directly through the waste layer to heat it. Indirect heating involves the working fluid not directly contacting the waste; the heat from the working fluid is transferred to the waste through a heat-conducting wall. Because waste is a poor conductor of heat, indirect heating is often inefficient and costly, making it difficult to implement in practical engineering. Therefore, direct heating is more advantageous. An oxygen-free environment means the waste cannot come into contact with oxygen.

[0005] For the practical engineering problem of waste incineration, using high-temperature flue gas without oxygen components as the working medium for heating waste is the most feasible technical approach. The most direct way to obtain high-temperature flue gas without oxygen components is to react air with the solid residue after waste pyrolysis through an oxidation reaction until all the oxygen in the air is consumed.

[0006] Compared to large-scale municipal solid waste incinerators, small incinerators have a smaller furnace volume. The lack of pretreatment before waste enters the furnace results in an uneven waste layer, leading to an unstable flow field within the furnace. This can easily cause significant changes in the matching relationship between waste and air, resulting in unstable high-temperature flue gas composition and pyrolysis reactions entering the pyrolysis zone. Consequently, the generated pyrolysis gas is unstable in composition, sometimes even lacking combustibility, making it difficult for the secondary combustion chamber to operate stably and causing excessive emissions of pollutants. Therefore, for small-scale municipal solid waste incinerators using pyrolysis technology, organizing an ideal and stable flow field within the furnace is crucial, and the air distribution system is key to organizing this flow field.

[0007] Therefore, developing an air distribution system that facilitates the organization of an ideal and stable flow field within the furnace is of great significance for the research and development of small-scale municipal solid waste incinerators with ultra-low emissions. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide an incinerator that solves the problem that existing waste pyrolysis gasification incinerators cannot achieve an ideal and stable flow field inside the furnace.

[0009] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0010] An incinerator, comprising:

[0011] Furnace body, wherein the interior of the furnace body is a cavity;

[0012] A grate, located inside the furnace body, divides the furnace body cavity into an upper furnace chamber and a lower ash chamber;

[0013] A slag collection hopper is located at the bottom of the furnace body;

[0014] The sidewall of the furnace body is provided with an outer shell, an insulation layer and a refractory layer in sequence from the outside to the inside; a tie anchor is provided between the refractory layer and the outer shell, one end of the tie anchor is fixed to the outer shell and the other end is embedded in the refractory layer; a slag-blocking bar is provided inside the slag collection hopper and the slag-blocking bar is provided on the inner surface of the slag collection hopper;

[0015] A smoke collection pipe is provided on the outer side wall of the furnace body, and the smoke collection pipe is connected to the interior of the furnace body through a gas gathering channel.

[0016] A secondary combustion chamber connected to the flue gas collection pipe, wherein a flue gas pipe is provided at the top of the secondary combustion chamber;

[0017] The gas-gathering channel includes a first gas-gathering channel plate and a second gas-gathering channel plate. One end of the first gas-gathering channel plate is fixed to the inner wall of the furnace body, and the other end is a free end that extends toward the second gas-gathering channel plate. One end of the second gas-gathering channel plate is fixed to the inner wall of the furnace body, and the other end is a free end that extends toward the first gas-gathering channel plate. The first gas-gathering channel plate and the second gas-gathering channel plate form an acute angle.

[0018] and an air distribution system installed on the incinerator, the air distribution system comprising:

[0019] An annular air duct is arranged around the inside of the side wall of the furnace body and has inward air blowing ports that communicate with the furnace chamber in the circumferential direction.

[0020] The main air supply pipe is located outside the furnace body and is equipped with a first air duct, a second air duct, and a third air duct.

[0021] The first air duct passes through the side wall of the furnace body and is connected to the annular air duct;

[0022] The second air duct passes through the side wall of the furnace body and extends to the ash and slag chamber; the second air duct is provided with a vertical pipe communicating with the ash and slag chamber; the vertical pipe passes through the grate, extends to the furnace chamber, and is provided with an outward air outlet communicating with the furnace chamber;

[0023] The third air duct passes through the side wall of the slag collection hopper and extends to the ash chamber;

[0024] The gas outlet direction of the inward blowing vent is inclined upward, and the gas outlet direction of the inward blowing vent points to the center line of the furnace. The first airflow enters the deep combustion zone through the inward blowing vent. The gas outlet direction of the inward blowing vent has an angle of 20-45° with the horizontal plane.

[0025] Optionally, the distance between the gas outlet of the outward blowing vent and the centerline of the furnace increases from top to bottom along the vertical pipe.

[0026] Optionally, the first air duct is provided with a first air regulating valve on the outside of the furnace body; and / or,

[0027] The second air duct is equipped with a second air regulating valve on the outside of the furnace body; and / or,

[0028] The third air duct is equipped with a third air regulating valve on the outside of the wall of the slag collection hopper.

[0029] Optionally, one or more of the first air regulating valve, the second air regulating valve, and the third air regulating valve may be electric valves.

[0030] Optionally, one or more of the first air regulating valve, the second air regulating valve, and the third air regulating valve may be manual valves.

[0031] Optionally, the manual valve includes:

[0032] The air duct is coaxial with the air duct to be adjusted;

[0033] A pivot seat, wherein the pivot seat is located on the outside of the air duct;

[0034] A rotating shaft, which passes through the air duct and the rotating shaft seat;

[0035] A fixed plate, wherein the fixed plate is disposed on the rotating shaft seat;

[0036] A baffle plate is disposed on the rotating shaft and located inside the air duct, so that the baffle plate can rotate around the axis of the rotating shaft inside the air duct.

[0037] A swing arm is mounted on the rotating shaft and located outside the air duct, allowing the swing arm to rotate around the axis of the rotating shaft outside the air duct. The swing arm is fixed to the fixed plate, and the relative position between the swing arm and the fixed plate indicates the valve flow rate. When the flow rate of the manual valve needs to be adjusted, the swing arm can be moved, thereby rotating the rotating shaft and causing the baffle plate to rotate by a certain angle. This changes the relative position between the baffle plate and the air duct, thereby changing the flow area of ​​the air duct and thus changing the flow rate of the air path. This, in turn, controls the reaction atmosphere in the deep combustion zone and the burnout zone, such as adjusting the oxygen concentration and gas temperature.

[0038] The air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator described in this invention operates as follows during incinerator operation:

[0039] The mixed air enters the main air supply pipe and is divided into three air paths:

[0040] The first airflow enters the annular airflow duct through the first airflow duct, and then enters the deep combustion zone of the furnace through the inward airflow port to participate in waste combustion;

[0041] The second airflow enters the vertical pipe through the second air duct, and then enters the deep combustion zone of the furnace through the outward air outlet to participate in the combustion of the waste pyrolysis residue.

[0042] The third airflow enters the ash chamber through the third air duct, where it exchanges heat with the ash and flows upward, passing through the gaps in the grate and entering the combustion zone of the furnace to participate in the combustion of the waste residue.

[0043] When it is necessary to adjust the flow rate of any one or more of the first, second, and third airflow channels, it can be done through the first, second, and third airflow regulating valves.

[0044] After the co-burning air passes through the deep combustion zone and the burnout zone, the oxygen component in it is depleted and the temperature rises, generally reaching above 600°C. Then the co-burning air enters the pyrolysis zone to provide energy for the pyrolysis reaction of the waste and produce pyrolysis gas containing combustible components. The pyrolysis gas is discharged from the exhaust pipe and flows downstream for further processing.

[0045] The incinerator of the present invention includes the air distribution system described above for a small-scale municipal solid waste pyrolysis gasification incinerator.

[0046] Preferably, the incinerator includes at least:

[0047] Furnace body, wherein the interior of the furnace body is a cavity;

[0048] A grate, located inside the furnace body, divides the furnace body cavity into an upper furnace chamber and a lower ash chamber;

[0049] A slag hopper is located at the bottom of the furnace body.

[0050] The above-described solution of the present invention has at least the following beneficial effects:

[0051] The air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator of the present invention actively delivers co-fired air in three separate streams to different reaction zones in the furnace to maintain waste reaction. It actively controls the flow field within the furnace, and can proactively control the oxygen supply to corresponding zones based on the oxygen demand patterns of the waste in different reaction zones. This improves the stability of the furnace flow field, optimizes the waste reaction process, reduces external energy consumption from various reactions and the loss on ignition of ash, enhances the stability of the pyrolysis gas composition and the smooth operation of the secondary combustion chamber, facilitates further treatment of the pyrolysis gas, and creates favorable conditions for the incinerator to achieve better emission levels. Specifically:

[0052] (1) The air distribution system actively controls the amount of oxygen required in each reaction zone according to the ideal oxygen supply pattern required by the waste in different reaction zones of the furnace, which is conducive to optimizing the reaction process of the waste.

[0053] (2) Forced air is introduced into different parts of the furnace, which helps to improve the stability of the flow field in the furnace and reduce the fluctuation of the reaction of waste in the furnace, thereby making the pyrolysis gas composition flowing out of the furnace more stable and more conducive to the downstream processing of pyrolysis gas.

[0054] (3) Some of the energy contained in the ash was recovered to improve the reaction inside the furnace and the temperature of the ash was reduced when it was discharged from the furnace to improve the safety of the operation. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator as described in Embodiment 1 of the present invention;

[0056] Figure 2 yes Figure 1 A magnified view of a portion of point I;

[0057] Figure 3 This is an isometric view of the second air duct, vertical duct, and outward air outlet assembly of the air distribution system for a small municipal solid waste pyrolysis gasification incinerator as described in Embodiment 1 of the present invention.

[0058] Figure 4 yes Figure 1 A magnified view of section II;

[0059] Figure 5 yes Figure 1 A magnified view of section III;

[0060] Figure 6 yes Figure 5 A cross-sectional view along the AA direction;

[0061] Figure 7 This is a schematic diagram of the incinerator described in Embodiment 2 of the present invention;

[0062] Figure 8 yes Figure 7 A schematic diagram along direction A;

[0063] Figure 9 yes Figure 7 A magnified view of a portion of point I;

[0064] Figure 10 yes Figure 9 A partial sectional view along the BB direction;

[0065] Figure 11 yes Figure 7 A magnified view of part II in the state before ash discharge from the ash chamber;

[0066] Figure 12 yes Figure 7 A magnified view of part II in the state after the ash slag chamber has not been discharged;

[0067] Figure 13 This is a schematic diagram of the furnace body of the incinerator described in Embodiment 2 of the present invention;

[0068] The components include: 1. Furnace body; 2. Furnace chamber; 3. Exhaust pipe; 4. Pyrolysis gas; 5. First air regulating valve; 6. First air duct; 7. Second air regulating valve; 8. Second air duct; 9. Third air regulating valve; 10. Third air duct; 11. Main air supply pipe; 12. Mixed combustion air; 13. Slag collection hopper; 14. Ash and slag; 15. Ash and slag chamber; 16. Third air duct; 17. Grate; 18. Combustion zone; 19. Circular air duct; 20. First air duct; 21. Deep combustion zone; 22. Second air duct; 23. Pyrolysis zone; 24. Vertical pipe; 25. Inward blowing air. 26. Outward air outlet; 27. Angle; 28. Air duct; 29. ​​Baffle plate; 30. Rotary shaft seat; 31. Fixed plate; 32. Swing arm; 33. Rotary shaft; 34. Smoke collection pipe; 35. Secondary combustion chamber; 36. Feed inlet; 37. Feed gate; 38. Gas gathering channel; 381. First gas gathering channel plate; 382. Second gas gathering channel plate; 39. Flue gas pipe; 40. Slag discharge port; 41. Slag discharge gate; 42. Outer shell; 43. Insulation layer; 44. Refractory layer; 45. Anchor; 46. Slag barrier bar; 47. Preheating and drying zone. Detailed Implementation

[0069] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0070] Example 1

[0071] like Figure 1-6 As shown, the air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator proposed in the embodiments of the present invention includes:

[0072] An annular air duct 19 is arranged around the inside of the side wall of the furnace body 1 and has an inward air outlet 25 that communicates with the furnace chamber 2 in the circumferential direction; the gas outlet of the inward air outlet 25 points to the center line of the furnace chamber 2.

[0073] The main air supply pipe 11 is located outside the furnace body 1 and is provided with a first air duct 6, a second air duct 8, and a third air duct 10.

[0074] The first air duct 6 passes through the side wall of the furnace body 1 and communicates with the annular air duct 19;

[0075] The second air duct 8 passes through the side wall of the furnace body 1 and extends to the ash chamber 15; the second air duct 8 is provided with a vertical pipe 24 communicating with the ash chamber 15; the vertical pipe 24 passes through the grate 17, extends to the furnace chamber 2, and is provided with an outward air outlet 26 communicating with the furnace chamber 2; the gas outlet of the outward air outlet 26 points to the four sides of the furnace chamber 2.

[0076] The third air duct 10 passes through the side wall of the slag collection hopper 13 and extends to the ash chamber 15.

[0077] The air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator described in this embodiment can be applied to an incinerator with the following structure: the incinerator includes a furnace body 1, a grate 17, a ash collection hopper 13, and an exhaust pipe 3, wherein the furnace body 1 has an internal cavity; the grate 17 is located inside the furnace body 1 and divides the cavity of the furnace body 1 into an upper furnace chamber 2 and a lower ash chamber 15; the ash collection hopper 13 is located at the bottom of the furnace body 1; and the exhaust pipe 3 is located on the side wall of the furnace body 1.

[0078] The waste has three main chemical reaction zones in the furnace 2. From top to bottom, they are the pyrolysis zone 23 where the pyrolysis reaction occurs, the deep burning zone 21 where the pyrolysis residue undergoes an incomplete oxidation reaction, and the burnout zone 23 where the deep burning residue is thoroughly burned. The ash 14 after burnout enters the ash chamber 15.

[0079] The working process of the air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator described in this embodiment is as follows:

[0080] The mixed air 12 enters the main air supply pipe 11 and is divided into three air paths:

[0081] The first airflow 20 enters the annular airflow 19 through the first airflow duct 6, and then enters the deep combustion zone 21 of the furnace 2 through the inward airflow vent 25 to participate in waste combustion;

[0082] The second airflow 22 enters the vertical pipe 24 via the second air duct 8, and then enters the deep combustion zone 21 of the furnace 2 through the outward air outlet 26 to participate in the combustion of waste pyrolysis residues.

[0083] The third airflow 16 enters the ash chamber 15 through the third air duct 10, exchanges heat with the ash 14, and then flows upward, passing through the gaps of the grate 17 and entering the combustion zone 18 of the furnace 2 to participate in the combustion of the waste deep incineration residue.

[0084] After the co-burning air 12 passes through the deep combustion zone 21 and the burnout zone 18, the oxygen component in it is depleted and the temperature rises, generally reaching above 600°C. Then the co-burning air 12 enters the pyrolysis zone 23 to provide energy for the pyrolysis reaction of the waste and generate pyrolysis gas 4 containing combustible components. The pyrolysis gas 4 is discharged from the exhaust pipe 3 and flows downstream.

[0085] In a preferred embodiment, the distance between the gas outlet of the outward-blowing vent 26 and the centerline of the furnace 2 increases from top to bottom along the vertical pipe 24. This arrangement ensures that the lower the gas outlet of the outward-blowing vent 26 is, the closer it is to the grate 17, the farther its gas outlet is from the centerline of the furnace 2. This results in all the outward-blowing vents 26 forming a roughly "pagoda" shape. This structure is more conducive to the entry of waste pyrolysis residue into the deep combustion zone 21, and makes the waste residue entering the burnout zone 18 more dispersed. Furthermore, the distribution of the second airflow 22 is more uniform, which can accelerate the reaction speed of the deep combustion zone 21 and the burnout zone 18.

[0086] The structural design of the outward air outlet 26 is not unique. In this embodiment, a specific design is provided. The vertical pipe 24 is located on the center line of the furnace 2, and the outward air outlet 26 is an air pipe provided on the vertical pipe 24. The air pipe is arranged circumferentially from top to bottom along the vertical pipe 24, and the length of the air pipe at the higher horizontal position is less than the length of the air pipe at the lower horizontal position, so that the distance between the gas outlet of the air pipe and the center line of the furnace 2 increases from top to bottom.

[0087] To create an ideal flow field, the gas outlet direction of the inward air vent 25 is inclined upwards. That is, the gas outlet direction of the inward air vent 25 points obliquely upwards towards the centerline of the furnace 2. The gas outlet direction of the inward air vent 25 has an angle 27 of 20-45° with the horizontal plane. This angle 27 within the aforementioned range helps to ensure a more uniform distribution of the first airflow 20 within the deep combustion zone 21, thereby improving the deep combustion effect of the waste pyrolysis residue.

[0088] To better control the gas flow of the first air duct 20, the second air duct 22, and the third air duct 16, the first air duct 6 is provided with a first air regulating valve 5 on the outside of the furnace body 1; the second air duct 8 is provided with a second air regulating valve 7 on the outside of the furnace body 1; and the third air duct 10 is provided with a third air regulating valve 9 on the outside of the wall of the slag collection hopper 13.

[0089] One or more of the first air regulating valve 5, the second air regulating valve 7, and the third air regulating valve 9 can be electric valves or manual valves. When electric valves are used, the flow rates of the three air streams can be automatically controlled by the incinerator's control system, thereby controlling the reaction atmosphere of the deep combustion zone 21 and the burnout zone 18, such as adjusting the oxygen concentration and gas temperature.

[0090] When using a manual valve, conventional manual valves of existing technology can be selected. However, this embodiment provides a preferred implementation. The manual valve includes: an air duct 28, a pivot seat 30, a pivot 33, a fixed plate 31, a baffle plate 29, and a swing arm 32. The air duct 28 is coaxial with the air duct to be adjusted; in this embodiment, taking the first air regulating valve 5 as an example, the air duct 28 is coaxial with the first air duct 6. The pivot seat 30 is located on the outside of the air duct 28. The pivot 33 passes through the air duct 28 and the pivot seat 20. The fixed plate 31 is located on the pivot seat 30. The baffle plate 29 is located on the pivot 33 and inside the air duct 28, allowing the baffle plate 29 to rotate around the axis of the pivot 33 inside the air duct 28. The swing arm 32 is mounted on the rotating shaft 33 and located outside the air duct 28, so that the swing arm 32 can rotate around the axis of the rotating shaft 33 outside the air duct 28; the swing arm 32 is fixed to the fixed plate 31, and the flow rate of the valve is indicated by the relative position between the swing arm 32 and the fixed plate 31.

[0091] When the flow rate of the aforementioned manual valve needs to be adjusted, the swing arm 32 can be moved to drive the rotating shaft 33 to rotate, thereby causing the baffle plate 29 to rotate at a certain angle, changing the relative position between the baffle plate 29 and the air duct 28, thereby changing the flow area of ​​the air duct 28, thus changing the flow rate of the air path, and thus controlling the reaction atmosphere of the deep combustion zone 21 and the burnout zone 18, such as the adjustment of oxygen concentration and gas temperature.

[0092] Example 2

[0093] like Figure 7-13 As shown, this embodiment proposes an incinerator, which includes the air distribution system for a small-scale municipal solid waste pyrolysis gasification incinerator described in Embodiment 1. The incinerator includes at least: a furnace body 1, a grate 17, and an ash collection hopper 13.

[0094] As a preferred implementation of this embodiment, the incinerator includes: furnace body 1, grate 17, flue gas collection pipe 34, exhaust pipe 3, secondary combustion chamber 35, and ash collection hopper 13;

[0095] The furnace body 1 has a hollow interior and a feed inlet 36 and a feed door 37 that can be sealed together with the feed inlet 36 at the top.

[0096] The grate 17 is located inside the furnace body 1 and divides the cavity of the furnace body 1 into the upper furnace chamber 2 and the lower ash chamber 15; that is, the space enclosed by the grate 17, the inner surface of the side wall of the furnace body 1, the top, and the feed door 37 is the furnace chamber 2, and the space enclosed by the grate 17, the inner surface of the side wall of the furnace body 1, the inner surface of the slag collection hopper 13, and the slag discharge door 41 is the ash chamber 15.

[0097] The smoke collection pipe 34 is located on the inner side wall of the furnace body 1 and communicates with the furnace chamber 2 through the gas gathering channel 38. The gas gathering channel 38 is composed of a first gas gathering channel plate 381 and a second gas gathering channel plate 382. One end of the first gas gathering channel plate 381 is fixed to the inner wall of the furnace body 1, and the other end is a free end that extends toward the second gas gathering channel plate 382. One end of the second gas gathering channel plate 382 is fixed to the inner wall of the furnace body 1, and the other end is a free end that extends toward the first gas gathering channel plate 381. The first gas gathering channel plate 381 and the second gas gathering channel plate 382 form an acute angle, and a gap is formed at the free ends of the first gas gathering channel plate 381 and the second gas gathering channel plate 382 that is suitable for gas to pass through and faces toward the bottom of the furnace body 1.

[0098] The exhaust pipe 3 is located on the outer side wall of the furnace body 1 and is connected to the smoke collection pipe 34;

[0099] The inlet of the secondary combustion chamber 35 is connected to the exhaust pipe 3, and the outlet is provided with a flue gas pipe 39;

[0100] The slag collection hopper 13 is located at the bottom of the furnace body 1, and is provided with a slag discharge port 40 and a slag discharge door 41 that can be sealed and fitted with the slag discharge port 40.

[0101] The geometric center of the feed inlet 36 coincides with the geometric center of the top of the furnace body 1. This arrangement improves the symmetry of the waste layer after it enters the furnace chamber 2 along the centerline of the furnace, preventing the waste layer from converging on one side of the furnace body 1 and causing flow problems in the furnace, which would be detrimental to various reactions.

[0102] The sidewall of the furnace body 1 is provided with an outer shell 42, an insulation layer 43, and a refractory layer 44 in sequence from the outside to the inside. The three-layer structure not only increases the durability of the furnace body 1, but also reduces the heat dissipation of the furnace body 1 and increases the strength of the furnace body 1.

[0103] In a preferred embodiment, an anchor 45 is provided between the refractory layer 44 and the outer shell 42. One end of the anchor 45 is fixed to the outer shell 42, and the other end is embedded in the refractory layer 44. The anchor 45 effectively prevents the refractory layer 44 from falling off, making the furnace body refractory layer more robust. In this embodiment, the end of the anchor 45 embedded in the refractory layer 44 is "L"-shaped, which makes it more stable and less prone to falling off. It should be noted that the specific structural design of the anchor 45 is not unique; the end of the anchor 45 embedded in the refractory layer 44 can also be "T"-shaped.

[0104] In a preferred embodiment, the ash collection hopper 13 is provided with ash-blocking bars 46 on its inner surface. Each time ash is discharged, the ash-blocking bars 46 prevent the ash from reaching the inner wall of the ash collection hopper 13, leaving some residual ash in the ash cavity 15. This retained cold ash can separate the subsequently falling hot ash 14 from the inner wall of the ash collection hopper 13, or reduce the likelihood of contact between the hot ash and the inner wall of the ash collection hopper. Since ash is a poor conductor of heat, this reduces the surface temperature of the outer wall of the ash collection hopper 13, improves the operational safety of the incinerator, reduces the heat dissipation of the ash, and facilitates a more ideal reaction of the waste within the furnace.

[0105] The working process of the small-scale municipal solid waste pyrolysis gasification incinerator described in this embodiment is as follows:

[0106] The feed door 37 is opened, and the waste to be processed is fed into the furnace 2 through the feed inlet 36. Then the feed door 37 is closed to prevent outside air from entering the furnace. The combustion air enters the furnace 2 through the air distribution system to maintain the series of reactions of the waste in the furnace 2. After a series of reactions such as preheating, drying, pyrolysis, deep burning and burnout in the furnace 2, the waste forms ash 14 and pyrolysis gas 4 containing organic combustible components. The ash 14 falls into the ash chamber 15 through the gaps in the grate 17.

[0107] The pyrolysis gas 4 enters the flue gas collecting pipe 34 through the gas gathering channel 38, and then enters the secondary combustion chamber 35 through the exhaust pipe 3. The pyrolysis gas 4 mixes with the secondary combustion air that enters the secondary combustion chamber 35 simultaneously, forming an oxygen-rich atmosphere in the secondary combustion chamber 35. The combustible components in the atmosphere undergo an oxidation reaction, releasing heat and converting the pyrolysis gas 4 into high-temperature flue gas with a higher temperature and a very low concentration of organic pollutants. This high-temperature flue gas is then discharged through the high-temperature flue gas pipe 39 or discharged downstream. The temperature of the high-temperature flue gas is 850℃-930℃.

[0108] The waste moves from top to bottom within the furnace 2, forming an oxygen-free preheating and drying zone 47, an oxygen-free pyrolysis zone 23, an oxygen-deficient deep combustion zone 21, and an oxygen-rich combustion zone 18 from top to bottom within the furnace 2.

[0109] Specifically, when the waste enters the furnace 2, it first enters the preheating and drying zone 47, which is in an oxygen-free atmosphere (here, "oxygen-free" refers to an extremely oxygen-deficient state with almost no oxygen). The waste is preheated and dried in the preheating and drying zone 47. During the preheating and drying process, the waste gradually moves towards the pyrolysis zone 23 in an oxygen-free atmosphere and further absorbs heat to raise the temperature to above 110°C, causing the moisture in the waste to evaporate further and some organic polymer components to approach the decomposition state.

[0110] Then, the waste enters the pyrolysis zone 23, where it further absorbs heat and heats up to the temperature range where the pyrolysis reaction can occur, and the pyrolysis reaction begins. The pyrolysis reaction includes the cracking reaction of the organic polymer components in the waste and the dry distillation reaction of the biomass components. Specifically, the organic polymer components in the waste, such as various plastics and rubbers, will undergo a cracking reaction when heated in an anaerobic atmosphere, generating combustible gases such as C2H4, C2H6, CH4, and H2, as well as carbon black, also known as a gasification reaction. The composition of the products varies at different temperatures; the higher the cracking temperature, the smaller the product molecules. The cracking reaction generally takes place in the temperature range of 280℃-650℃. Simultaneously, the biomass components in the waste, such as leaves and wood, will undergo a dry distillation reaction in an anaerobic atmosphere, generating gaseous wood tar in the furnace, wood gas containing combustible components such as CH4, H2, and CH3OH, and solid carbon, also known as a carbonization reaction. Carbonization reactions typically occur within a temperature range of 250℃-600℃, similar to the principle of common wood charcoal production. The aforementioned reactions are highly complex, with various reactions intertwined and lacking clear temperature, time, or physical spatial boundaries. Both pyrolysis and distillation reactions are endothermic, meaning they require external heat to continue. The heat sustaining the reaction includes high-temperature flue gas flowing upwards in the opposite direction to the waste's movement. Although waste is a poor conductor of heat, the high-temperature flue gas seeps through the gaps in the waste layer, directly and fully contacting the waste, resulting in rapid heat absorption and pyrolysis.

[0111] Next, the waste residue and solid products after the pyrolysis reaction move downward in the furnace 2 and enter the deep combustion zone 21 with a moderately oxygen-deficient atmosphere. They come into contact with the mixed combustion air and undergo an incomplete oxidation reaction in the deep combustion zone 21 to generate combustible components such as CO and H2 and non-combustible components such as CO2, and release heat.

[0112] Finally, the waste residue and solid products after deep combustion, such as refractory components, inert substances, and solid carbon in the waste, move downward in the furnace 2 and enter the oxygen-rich combustion zone 18. In the combustion zone 18, they come into contact with the oxygen-containing mixed combustion air and undergo a full oxidation reaction, releasing heat and forming ash slag 14 with a very low loss on ignition. The ash slag 14 enters the ash chamber 15 through the gaps in the grate 17.

[0113] It can be seen that the movement of the waste and its reaction products and residues in the furnace 2 is a gradual downward movement, and the morphological change process is from raw waste to dry waste, pyrolysis residues, deep combustion residues, and ash 14.

[0114] In a preferred embodiment, when the waste reacts in the furnace 2, a co-combustion air is introduced into the furnace 2 through the air distribution system. A portion of this co-combustion air enters the ash chamber 15, absorbs some heat from the ash 14, and then rises through the grate 17 into the burnout zone 18 and the deep combustion zone 21, where it co-combusts with other co-combustion air entering the furnace. This maintains the continuous progress of various reactions in the burnout zone 18 and the deep combustion zone 21. The oxygen component in the co-combustion air is gradually consumed, and the temperature rises. Then, the co-combustion air enters the pyrolysis zone 23, causing the waste to undergo a pyrolysis reaction, forming pyrolysis gas 4 containing combustible components. Finally, the co-combustion air enters the preheating and drying zone 47 to preheat and dry the waste, and lower its temperature.

[0115] It can be seen that the movement of the combustion air in the furnace 2 is gradually upward, its temperature changes by first rising and then falling, and its oxygen content changes by gradually decreasing to zero.

[0116] It should also be noted that the small-scale municipal solid waste clean incineration system described in this invention is mainly used in small-scale municipal solid waste incinerators, but it can also be used in other applications, including but not limited to medium-sized municipal solid waste incinerators, medical waste incinerators, industrial solid waste incinerators, etc.

[0117] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An incinerator, characterized in that, include: The furnace body (1) has a cavity inside; the top is provided with a feed inlet (36) and a feed door (37) that is sealed to the feed inlet (36); A grate (17) is located inside the furnace body (1) and divides the cavity of the furnace body (1) into an upper furnace chamber (2) and a lower ash chamber (15). The furnace body (1) includes a flue pipe (34), a secondary combustion chamber (35), an exhaust pipe (3), and a slag collection hopper (13). The slag collection hopper (13) is located at the bottom of the furnace body (1). The slag collection hopper (13) is provided with slag-blocking bars (46) inside, which are located on the inner surface of the slag collection hopper (13). The space enclosed by the grate (17), the inner surface of the side wall of the furnace body (1), the top, and the feed door (37) is the furnace chamber (2), and the space enclosed by the grate (17), the inner surface of the side wall of the furnace body (1), the inner surface of the slag collection hopper (13), and the slag discharge door (41) is the ash chamber (15). The smoke collection pipe (34) is located on the inner side wall of the furnace body (1) and communicates with the furnace chamber (2) through the gas gathering channel (38). The gas gathering channel (38) includes a first gas gathering channel plate (381) and a second gas gathering channel plate (382). One end of the first gas gathering channel plate (381) is fixed to the inner wall of the furnace body (1), and the other end is a free end that extends toward the second gas gathering channel plate (382). One end of the second gas gathering channel plate (382) is fixed to the inner wall of the furnace body (1). On the inner wall of the furnace body (1), one end is a free end and extends toward the first gas gathering channel plate (381); the first gas gathering channel plate (381) and the second gas gathering channel plate (382) form an acute angle; and a gap suitable for gas passage is formed at the free ends of the first gas gathering channel plate (381) and the second gas gathering channel plate (382) facing the bottom of the furnace body (1); the exhaust pipe (3) is provided on the outer side wall of the furnace body (1) and is connected to the smoke collecting pipe (34); The inlet of the secondary combustion chamber (35) is connected to the exhaust pipe (3), and the outlet is provided with a flue gas pipe (39); the slag collection hopper (13) is provided with a slag discharge port (40) and a slag discharge door (41) that is sealed to the slag discharge port (40); the geometric center of the feed inlet (36) coincides with the geometric center of the top of the furnace body (1); The side wall of the furnace body (1) is provided with an outer shell (42), an insulation layer (43) and a refractory layer (44) from the outside to the inside; a tie anchor (45) is provided between the refractory layer (44) and the outer shell (42), one end of the tie anchor (45) is fixed on the outer shell (42), and the other end is embedded in the refractory layer (44); The slag collection hopper (13) is provided with slag-blocking bars (46) inside, the slag-blocking bars (46) are provided on the inner surface of the slag collection hopper (13), and the anchor (45) is set in an "L" shape or a "T" shape. and an air distribution system installed on the incinerator, the air distribution system comprising: Annular air duct (19), the annular air duct (19) is arranged around the inside of the side wall of the furnace body (1), and is provided with an inward air blowing port (25) that communicates with the furnace chamber (2) in the circumferential direction. The main air supply pipe (11) is located outside the furnace body (1) and is provided with a first air duct (6), a second air duct (8) and a third air duct (10). The first air duct (6) passes through the side wall of the furnace body (1) and is connected to the annular air duct (19); The second air duct (8) passes through the side wall of the furnace body (1) and extends to the ash chamber (15); the second air duct (8) is provided with a vertical pipe (24) communicating with the ash chamber (15); the vertical pipe (24) passes through the grate (17) and extends to the furnace (2), and is provided with an outward air outlet (26) communicating with the furnace (2); The third air duct (10) passes through the side wall of the slag collection hopper (13) and extends to the ash chamber (15). The vertical pipe (24) is located on the center line of the furnace (2), and the outward air outlet (26) is an air pipe provided on the vertical pipe (24); the air pipe is arranged circumferentially from top to bottom along the vertical pipe (24), and the length of the air pipe at the higher horizontal position is less than the length of the air pipe at the lower horizontal position, so that the distance between the gas outlet of the air pipe and the center line of the furnace (2) increases from top to bottom; The gas outlet direction of the inward air vent (25) is inclined upward, and the gas outlet direction of the inward air vent (25) points to the center line of the furnace (2). The first air (20) enters the deep combustion zone (21) through the inward air vent (25). The gas outlet direction of the inward air vent (25) has an angle (27) of 20-45° with the horizontal plane. The mixed air (12) enters the main air supply pipe (11) and is divided into three air paths; the first air path (20) enters the annular air duct (19) through the first air duct (6), and then enters the deep combustion zone (21) of the furnace (2) from the inward air outlet (25) to participate in the combustion of waste; the second air path (22) enters the vertical pipe (24) through the second air duct (8), and then enters the deep combustion zone (21) of the furnace (2) from the outward air outlet (26) to participate in the combustion of waste pyrolysis residue; the third air path (16) enters the ash chamber (15) through the third air duct (10). While exchanging heat with the ash (14), the air (12) flows upward, passes through the gap of the grate (17) and enters the burnout zone (18) of the furnace (2), participating in the combustion of the waste residue. After the combustion air (12) passes through the deep combustion zone (21) and the burnout zone (18), the oxygen component in it is depleted, the temperature rises to above 600°C, and then the combustion air (12) enters the pyrolysis zone (23) to provide energy for the pyrolysis reaction of the waste and generate pyrolysis gas (4) containing combustible components. The pyrolysis gas (4) is discharged from the exhaust pipe (3) and flows downstream. The distance between the gas outlet of the outward blowing port (26) and the center line of the furnace (2) increases from top to bottom along the vertical pipe (24); The first air duct (6) is provided with a first air regulating valve (5) on the outside of the furnace body (1); and / or, The second air duct (8) is provided with a second air regulating valve (7) on the outside of the furnace body (1); and / or, The third air duct (10) is provided with a third air regulating valve (9) on the outside of the wall of the slag collection hopper (13); Among them, one or more of the first air regulating valve (5), the second air regulating valve (7), and the third air regulating valve (9) are electric valves; Among them, one or more of the first air regulating valve (5), the second air regulating valve (7), and the third air regulating valve (9) are manual valves; The manual valve includes: Air duct (28), the air duct (28) is coaxial with the air duct to be adjusted; pivot seat (30), the pivot seat (30) is located on the outside of the air duct (28); A rotating shaft (33) passes through the air duct (28) and the rotating shaft seat (30); a fixed plate (31) is disposed on the rotating shaft seat (30); A baffle plate (29) is provided on the rotating shaft (33) and located inside the air duct (28), so that the baffle plate (29) can rotate around the axis of the rotating shaft (33) inside the air duct (28); A swing arm (32) is mounted on the rotating shaft (33) and located outside the air duct (28), allowing the swing arm (32) to rotate around the axis of the rotating shaft (33) outside the air duct (28); the swing arm (32) is fixed to the fixed plate (31), and the flow rate of the valve is indicated by the relative position between the swing arm (32) and the fixed plate (31); By moving the swing arm (32), the rotating shaft (33) is driven to rotate, thereby causing the baffle plate (29) to rotate at a certain angle, changing the relative position between the baffle plate (29) and the air duct (28), thereby changing the flow area of ​​the air duct (28), changing the flow rate of the air duct, and thus controlling the reaction atmosphere of the deep burning zone (21) and the burnout zone (18).

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