Multi-air-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler

Abstract

The invention discloses a multi-air-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler, and belongs to the technical field of solid waste energy treatment. According to the boiler, a multi-air-chamber structure is adopted for achieving self-adaptive fluidized combustion of garbage, a traditional cyclone separator and a traditional material returning system are omitted, the zero-power-consumption built-in inertia separation technology is integrated, and a low-resistance and high-efficiency static fluidized bed system is formed; the core of the method is that a technology of recirculating high-temperature flue gas to a dense-phase region is introduced, the high-temperature flue gas of about 500 DEG C in a third return stroke is accurately introduced back to the dense-phase region of the fluidized bed, and dual functions of energy feedback and combustion environment reconstruction are realized: on one hand, the temperature stability of a bed layer is improved through sensible heat reinjection, and self-sustaining combustion without external combustion supporting is realized; and on the other hand, the oxygen concentration of the dense-phase region is diluted through oxygen-poor flue gas, the ideal low-oxygen, high-temperature and high-turbulence combustion environment is constructed, generation of NOx and dioxin is actively inhibited from the chemical reaction path level, and the original emission concentration of pollutants is remarkably reduced. The method is suitable for efficient low-carbon incineration treatment of multi-source waste such as municipal solid waste and industrial solid waste.

Description

Technical Field

[0001] This invention relates to the field of solid waste treatment technology, specifically to a fluidized bed incinerator for the incineration of various solid wastes such as municipal solid waste and industrial waste, and more particularly to a multi-chamber self-combustion fluidized bed waste incinerator that can achieve high-temperature and low-oxygen combustion, significantly save fossil fuel combustion aid, and achieve energy self-sustaining operation; this boiler can be widely used in cogeneration, industrial steam supply and other scenarios. Background Technology

[0002] With the accelerated urbanization process and the full implementation of the waste sorting system in my country, the amount of urban domestic waste generated and the demand for its treatment continue to grow. Waste-to-energy incineration has become the mainstream method for the harmless, reduced-volume, and resource-based disposal of solid waste. Currently, the mainstream technologies in the waste incineration field mainly include two categories: mechanical grate furnaces and traditional circulating fluidized bed incinerators. However, both types of technologies have significant drawbacks.

[0003] Mechanical grate incinerators suffer from poor adaptability to waste calorific value, insufficient combustion uniformity, incomplete combustion, and high carbon content in fly ash, resulting in limited energy utilization efficiency. While traditional circulating fluidized bed incinerators offer advantages such as high combustion efficiency, wide load adjustment range, and strong adaptability to fluctuations in waste calorific value, they generally suffer from complex system structures, high furnace and flue resistance, and high operating energy consumption. Furthermore, when processing low-calorific-value waste, they require frequent addition of auxiliary fuels such as oil, natural gas, and coal to maintain stable furnace temperature, significantly increasing project operating costs and weakening the project's economic viability. Additionally, traditional circulating fluidized bed incinerators often employ a high-oxygen, rich-fuel mode, which easily generates large amounts of thermal nitrogen oxides (NOx) during combustion. x This leads to high pressure and high treatment costs for end-of-pipe denitrification.

[0004] In existing technologies, for NO x Emission control commonly employs selective non-catalytic reduction (SNCR) or selective catalytic reduction (SCR) technologies. These technologies are end-of-pipe treatments and cannot suppress pollutant generation at the combustion source, while also increasing equipment investment and operation and maintenance costs. Furthermore, traditional circulating fluidized bed incinerators rely on external cyclone separators and return systems to achieve material circulation and combustion. Such devices not only have high equipment investment but also high failure rates and require significant maintenance, further increasing the project's total life-cycle cost.

[0005] Therefore, the waste incineration industry urgently needs a new incineration technology that can achieve a four-in-one integration of "high-efficiency combustion, clean emissions, energy saving and consumption reduction, and stable operation" based on the essence of combustion. In recent years, high-temperature low-oxygen combustion technology has shown excellent pollutant formation inhibition effects and energy efficiency improvement potential in laboratory studies. However, due to technical bottlenecks in the industrial scale-up process, this principle has not yet been applied on a large scale in the field of waste incineration. Based on this, developing a high-temperature low-oxygen combustion technology and supporting equipment suitable for waste incineration scenarios has become an urgent need for the industry's development. Summary of the Invention

[0006] The purpose of this invention is to overcome the pain points of existing waste incineration technologies, such as low combustion efficiency, high energy consumption, large pollutant emissions, high operating costs, and poor system stability. It provides a multi-chamber, high-temperature, low-oxygen, self-contained fluidized bed waste incineration boiler and its combustion method. By reconstructing the combustion system structure and optimizing the combustion control logic, it achieves energy saving, efficiency improvement, ultra-low emissions, and large-scale application of waste incineration. This invention is the first to engineer the principle of "high-temperature, low-oxygen combustion" into the field of waste incineration. Through high-temperature flue gas recirculation technology, it achieves the integration of energy self-sufficiency and pollutant source control. The system structure is significantly simplified, the operation is stable and reliable, and the control is completely autonomous and controllable, providing a feasible and scalable technical path for the waste incineration industry to achieve carbon neutrality.

[0007] Technical solution

[0008] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows:

[0009] 1. Combustion System Restructuring: The external cyclone separator and return system found in traditional circulating fluidized bed incinerators are eliminated, and an innovative integrated carbon burnout system combining gas-solid inertial gravity separation and fluidized bed combustion is designed. Through a ventilated furnace structure with a multi-chamber layout of dual main air chambers and dual auxiliary air chambers, it not only significantly outperforms traditional mechanical grate waste incinerators in terms of energy saving, efficiency improvement, and ultra-low emissions, but also possesses good potential for large-scale application, solving problems such as uneven combustion and excessive resistance that exist in the large-scale application of traditional fluidized bed incinerators.

[0010] 2. High-Temperature Flue Gas Recirculation System: A high-temperature flue gas extraction port is pre-positioned at the upper part of the third pass flue of the boiler to extract clean high-temperature flue gas at a temperature of 450℃~500℃. This clean high-temperature flue gas is transported to the lower part of the dense phase zone of the furnace through a high-temperature resistant pipeline. The heat of the high-temperature flue gas is used to raise the initial temperature of the furnace and enhance the waste combustion reaction process. At the same time, the oxygen concentration in the furnace is reduced through the dilution effect of the flue gas, thus inhibiting thermal NO from the source. xThe system is equipped with an intelligent regulating valve group and an oxygen concentration feedback control system, which can dynamically adjust the flue gas recirculation flow rate according to parameters such as real-time oxygen concentration and bed temperature in the furnace, ensuring that the furnace temperature is stably maintained at ≥900℃, meeting the temperature requirements for complete combustion of waste and decomposition of dioxins.

[0011] 3. Intelligent control system: integrates bed temperature, oxygen concentration, furnace pressure, and flue gas composition (including NO). x Online monitoring sensors (such as CO and O2) enable real-time acquisition, transmission, and analysis of core boiler operating parameters. Based on artificial intelligence (AI) algorithms, a dynamic coupling model of "waste characteristics-air distribution strategy-flue gas circulation-combustion state" is established. The model performs real-time calculations and optimizations on the collected multi-dimensional parameters, automatically adjusting key operating parameters such as the air distribution ratio of the main air chamber and auxiliary air chamber, the high-temperature flue gas recirculation flow rate, and the feeding rate. This achieves fully automatic closed-loop control of the entire boiler combustion process, ensuring that the combustion system is always in optimal operating condition.

[0012] 4. Technological Paradigm Innovation: Breaking through the limitations of traditional waste incineration technology that "controls the combustion state by adjusting the amount of air", the technology combines the reconstruction of the combustion system structure with high-temperature flue gas recirculation technology to achieve a technological paradigm shift from "adjusting air" to "reconstructing the combustion reaction environment", artificially creating an optimal combustion environment with high temperature and low oxygen, while taking into account both combustion efficiency and pollutant control.

[0013] 5. Core technology implementation: For the first time, the principle of "high temperature and low oxygen combustion" has been transformed from laboratory research into an engineering application in the field of waste incineration, solving technical challenges such as temperature uniformity control and combustion stability assurance faced by high temperature and low oxygen combustion technology in industrial scale-up.

[0014] 6. Integrated Functionality: Through the design of the high-temperature flue gas recirculation system, the two core functions of energy self-sufficiency and pollutant source control are realized simultaneously, eliminating the need for additional pollutant control devices, simplifying the system structure and reducing treatment costs.

[0015] 7. Improved system reliability: The complex structure of traditional fluidized beds is simplified, and the easily faulty external cyclone separator and return system are eliminated. Through multi-chamber layout and integrated combustion design, the system's operational stability and ease of operation are improved, the equipment failure rate and maintenance costs are reduced, and a fully autonomous and controllable operation mode is achieved.

[0016] 8. Carbon neutrality and technological support: By significantly reducing auxiliary fuel consumption, improving energy efficiency, and reducing pollutant emissions, it provides technological support for the low-carbon operation of waste incineration projects, helping the industry move towards the goal of carbon neutrality.

[0017] Beneficial effects

[0018] Compared with the prior art, the present invention has the following significant advantages:

[0019] 1. Significantly reduced energy consumption: The gas-solid inertial gravity separation technology is replaced by the traditional cyclone separation technology, which significantly reduces the flow resistance of flue gas and can save more than 30% of the power consumption of the induced draft fan; the return material system is eliminated and optimized into a secondary combustion chamber structure, which not only reduces the flow resistance of the primary air and can save 30%-40% of the power consumption of the blower, but also extends the residence time of the material in the furnace and improves the combustion efficiency.

[0020] 2. Improved carbon burnout: Through multi-chamber air distribution optimization and carbon burnout design of the secondary combustion chamber, the degree of burnout of fixed carbon in waste is significantly improved, the carbon content of fly ash is reduced, and energy utilization efficiency is improved.

[0021] 3. NO x Emission source reduction: The dense phase zone of the furnace creates a low-oxygen combustion environment through high-temperature flue gas dilution, fundamentally suppressing thermal NOx. x NO is generated during combustion. x The initial concentration of nitrogen oxides is reduced by 30% to 50% compared to traditional circulating fluidized bed incinerators, significantly reducing the pressure and cost of end-of-pipe denitrification.

[0022] 4. Thermal efficiency optimization: The high-temperature flue gas recirculation system recovers and utilizes the waste heat of the flue gas, reducing exhaust heat loss. The boiler thermal efficiency is 1-3 percentage points higher than that of traditional circulating fluidized bed incinerators, and the energy utilization efficiency is significantly improved.

[0023] 5. Reduced operating costs: Energy self-sufficiency is achieved through high-temperature flue gas recirculation, which significantly reduces or completely replaces the consumption of external auxiliary fuels such as oil and natural gas, thereby significantly reducing boiler operating costs and improving the project's economic efficiency.

[0024] 6. Ultra-low dioxin emissions: The dual effects of high temperature (furnace temperature ≥900℃) and low oxygen environment inhibit the synthesis of dioxin precursors. Combined with a residence time of ≥2s for flue gas in the furnace, it ensures that the generated dioxins are fully decomposed, achieving ultra-low dioxin generation and emissions, and meeting stringent environmental standards.

[0025] 7. Enhanced system stability: The simplified complex structure of traditional fluidized beds reduces vulnerable parts and failure points. The combination of multi-chamber layout and intelligent control system ensures stable and controllable combustion process, adapts to fluctuations in waste feed with different calorific values ​​and compositions, and improves the equipment's adaptability to waste.

[0026] 8. Feasibility for large-scale application: The trouser-shaped furnace and multi-chamber structure design solves the problems of uneven combustion and uneven temperature distribution encountered in the process of scaling up traditional fluidized beds, and has good potential for large-scale application, which can meet the needs of large-scale waste incineration. Attached Figure Description

[0027] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0028] In the attached diagram:

[0029] Figure 1 This is a front view of the single-furnace structure of the present invention;

[0030] Figure 2 This is a front view of the furnace structure of the underpants of the present invention;

[0031] The component numbers in the diagram are as follows:

[0032] 1-Main air chamber, 2-Main air distribution plate, 3-Auxiliary air chamber, 4-Auxiliary air distribution plate, 5-Front wall of main combustion chamber (furnace), 6-Rear wall of main combustion chamber (furnace), 7-Outlet of second-pass downward tapering flue, 8-Main combustion chamber (furnace), 9-Forward and upward inclined tapering section of furnace rear wall, 10-Second-pass downward tapering flue, 11-Water-cooled partition wall for guiding flue gas (lower and upper sections), 12-Flue gas outlet of main combustion chamber (furnace), 13-Water (steam) cooled roof, 14-High-temperature superheater, 15-Third-pass flue gas outlet of auxiliary combustion chamber, 16-Vertical shaft flue, 17-Front wall of vertical shaft 18-Vertical shaft rear wall membrane water-cooled wall, 19-Auxiliary combustion chamber three-pass flue, 20-Vertical shaft flue outlet, 21-Side symmetrical water-cooled wall, 22-Front main air chamber, 23-Rear main air chamber, 24-Furnace front main air chamber wall, 25-Front auxiliary air chamber, 26-Rear auxiliary air chamber, 27-Front auxiliary combustion chamber three-pass flue front wall water-cooled wall, 28-Front two-pass downward tapering flue outlet, 29-Front auxiliary combustion chamber three-pass flue, 30-Front guide flue gas first downward then upward water-cooled partition wall, 31-Shorts-type main combustion chamber (furnace), 32-Shorts-type 33 - Rearwardly inclined tapering section of the water-cooled wall in front of the main combustion chamber (furnace); 34 - High-temperature superheater of the first three-pass flue; 35 - Downward tapering flue of the first two-pass flue; 36 - Flue gas outlet of the rear furnace; 37 - Flue gas outlet of the front of the "pants" furnace; 38 - Outlet of the upward flue of the first three-pass flue; 39 - Water-cooled sealed roof of the furnace and the first and second-pass flues; 40 - Upper wall of the longitudinal water-cooled flue; 41 - Longitudinal flue; 42 - Flue gas outlet of the rear three-pass flue; 43 - Flue gas inlet of the vertical shaft flue; 44 - Water-cooled wall shared by the rear wall of the rear three-pass flue and the front wall of the vertical shaft; 45 - Rear three-pass flue... 45 - High-temperature superheater of the flue gas duct; 46 - Forward inclined tapering section of the rear wall of the trouser furnace; 47 - Common water-cooled wall of the rear wall of the second and third flue gas ducts; 48 - Rear wall of the vertical shaft flue gas duct; 49 - Flue gas outlet of the second and third flue gas duct; 50 - Flue gas inlet of the third flue gas duct; 51 - Flue gas outlet of the vertical shaft flue gas duct; 52 - Third flue gas duct; 53 - Auxiliary combustion chamber; 54 - Upward flue gas duct of the third flue gas duct; 55 - Front auxiliary combustion chamber; 56 - Rear auxiliary combustion chamber; 57 - Air distribution plate of the front auxiliary combustion chamber; 58 - Air distribution plate of the rear auxiliary combustion chamber. Detailed Implementation

[0033] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Example 1: Single furnace structure

[0035] Please see the appendix Figure 1This embodiment provides a multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler with a single furnace structure, and its structural features are as follows:

[0036] The boiler adopts a "one main, one auxiliary" combustion system layout, that is, one main combustion chamber (furnace) 8 is matched with one main air chamber 1, and one auxiliary combustion chamber 53 is matched with one set of two-pass and three-pass flues and one auxiliary air chamber 3. Among them, the lower end of the main combustion chamber (furnace) 8 is equipped with a main air distribution plate 2, which is connected to the main air chamber 1. The main air chamber 1 is used to introduce primary air into the main combustion chamber (furnace) 8 to provide the basic airflow for fluidized bed combustion. The upper end of the main combustion chamber (furnace) 8 is equipped with a water (steam) cooled roof 13, the front side is equipped with a furnace front wall 5, and the rear side is equipped with a furnace rear wall 6. The upper part of the furnace rear wall 6 is equipped with a forward and upward inclined tapering section 9, forming a flue gas guiding structure to guide the flue gas in the furnace to flow towards the two-pass flue.

[0037] The lower end of the auxiliary combustion chamber 53 is provided with an auxiliary air distribution plate 4, which is connected to the auxiliary air chamber 3. The auxiliary air chamber 3 is used to introduce secondary air into the auxiliary combustion chamber 53 to enhance the secondary combustion of unburned carbon. The upper end of the auxiliary combustion chamber 53 is connected to the outlet 7 of the second-pass downward tapering flue and the inlet 19 of the third-pass flue gas. The front wall is seamlessly connected to the rear wall 6 of the main combustion chamber (furnace) and the rear wall is seamlessly connected to the front wall 17 of the vertical shaft. The two side walls are water-cooled walls in a side-symmetrical mode, forming a closed combustion space.

[0038] The second-pass downward tapering flue 10 is located in front of the guide flue gas first-down-then-up water-cooled partition wall 11. Its upper end is connected to the flue gas outlet 12 of the main combustion chamber (furnace) and its lower end is connected to the outlet 7 of the second-pass downward tapering flue. The third-pass flue 52 is located behind the guide flue gas first-down-then-up water-cooled partition wall 11. Its upper end is connected to the water (steam) cooled roof 13 and its lower end is connected to the third-pass flue gas inlet 19. Through the guiding effect of the guide flue gas first-down-then-up water-cooled partition wall 11, the flue gas forms a "first downward-then-up" flow path in the second-pass and third-pass flues, extending the flue gas residence time.

[0039] The high-temperature superheater 14 is installed in the upper, non-wear-resistant area of ​​the three-pass flue 52 to absorb heat from the flue gas and heat the steam. The vertical flue 16 is located behind the auxiliary combustion chamber 53. Its front wall is a vertical flue front wall membrane water-cooled wall 17, and its rear wall is a vertical flue rear wall membrane water-cooled wall 18. The upper end is provided with a vertical flue outlet 20, and the lower end is connected to the three-pass flue 52 through the auxiliary combustion chamber three-pass flue gas outlet 15 to guide the flue gas into the subsequent tail heating surface.

[0040] Example 2: Underpants Furnace Structure

[0041] Please see the appendix Figure 2This embodiment provides a multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler with a trouser-shaped furnace structure, suitable for large-scale waste incineration scenarios. Its structural features are as follows:

[0042] The core combustion unit of the boiler is a trouser-shaped main combustion chamber (furnace) 31. A front main air chamber 22 is set on the front side of its lower end, and a rear main air chamber 23 is set on the rear side of its lower end. The front main air chamber 22 and the rear main air chamber 23 are arranged symmetrically. Primary air is introduced into the trouser-shaped main combustion chamber (furnace) 31 through corresponding air distribution plates to achieve uniform fluidized combustion of materials in the furnace. The upper end of the trouser-shaped main combustion chamber (furnace) 31 is provided with a water-cooled sealed roof 38 for the furnace and the front and rear secondary flues. The upper middle part of the front wall extends backward to form a backward inclined tapering section 32 of the front water-cooled wall, and the upper middle part of the rear wall extends forward to form a forward inclined tapering section 45 of the rear wall. The inclined tapering structure guides the flue gas to be diverted to the secondary flues on both sides.

[0043] The front and rear sides of the trouser-shaped main combustion chamber (furnace) 31 are symmetrically provided with the first two-pass downward tapering flue 34, the second-pass downward tapering flue, the first three-pass upward flue 29, and the third-pass upward flue 54, and are correspondingly configured with the front auxiliary combustion chamber 55 and the rear auxiliary combustion chamber 56, forming a double-sided symmetrical combustion and heat exchange system.

[0044] Among them, the front wall of the first two-pass downward tapering flue 34 is a water-cooled wall that guides the flue gas downward to the front auxiliary combustion chamber 55, the rear wall is seamlessly connected to the front wall of the trouser-shaped main combustion chamber (furnace) 31, the upper end is sealed to the water-cooled sealed roof 38, the lower end is seamlessly connected to the upper end of the front auxiliary combustion chamber 55, and the two side walls are symmetrical water-cooled walls; the outlet of the first two-pass downward tapering flue 34 is the outlet 28 of the first two-pass downward tapering flue, which is connected to the inlet of the first three-pass upward flue 29.

[0045] The front wall of the second-pass downward tapering flue is seamlessly connected to the rear wall 45 of the trouser-shaped main combustion chamber (furnace) 31. The rear wall is a water-cooled wall 46 that guides the flue gas downward to the rear auxiliary combustion chamber 56. The upper end is sealed to the water vapor-cooled sealing roof 38, and the lower end is seamlessly connected to the upper end of the rear auxiliary combustion chamber 56. The two side walls are symmetrical water-cooled walls. The outlet of the second-pass downward tapering flue is the flue gas outlet 49 of the second-pass downward tapering flue, which is connected to the inlet 50 of the third-pass upward flue 54.

[0046] The front wall of the first three-pass upward flue 29 is the front wall of the whole machine, and the rear wall is the same water-cooled wall structure as the front wall of the first two-pass downward tapering flue 34. The upper end is provided with the outlet 37 of the first three-pass upward flue, which is connected to the longitudinal flue 40, and the lower end is seamlessly connected to the upper end of the front auxiliary combustion chamber 55. The upper non-wear area of ​​the first three-pass flue 29 is equipped with the high-temperature superheater 33 of the first three-pass flue, which is used to absorb the heat of the flue gas.

[0047] The front wall of the third-pass upward flue 54 and the rear wall 46 of the second-pass downward tapering flue are the same water-cooled wall structure. The rear wall is seamlessly connected to the front wall 43 of the vertical shaft. The upper end is provided with the flue gas outlet 41 of the third-pass flue, which is connected to the flue gas inlet 42 of the vertical shaft flue. The lower end is seamlessly connected to the upper end of the rear auxiliary combustion chamber 56. The high-temperature superheater 44 of the third-pass flue is installed in the upper non-wear area of ​​the third-pass flue 54.

[0048] A front auxiliary air chamber 25 is provided at the lower end of the front auxiliary combustion chamber 55. The front auxiliary air chamber 25 is equipped with a front auxiliary combustion chamber air distribution plate 57 for introducing secondary air. The upper end of the front wall of the front auxiliary combustion chamber 55 is tightly sealed to the lower end of the front wall 27 of the whole machine, and the upper end of the rear wall is tightly sealed to the front wall 24 of the trouser-type main combustion chamber (furnace) 31. The upper end is connected to the outlet 28 of the first two-pass downward tapering flue and the inlet of the first three-pass flue. The two side walls are symmetrical water-cooled walls, forming a closed secondary combustion space.

[0049] A rear auxiliary air chamber 26 is provided at the lower end of the rear auxiliary combustion chamber 56. The rear auxiliary air chamber 26 is equipped with a rear auxiliary combustion chamber air distribution plate 58 for introducing secondary air. The upper end of the front wall of the rear auxiliary combustion chamber 56 is sealed to the rear wall of the trouser-shaped main combustion chamber (furnace) 31. The upper end of the rear wall is sealed to the lower end of the front wall 43 of the vertical shaft. The upper end is connected to the flue gas outlet 49 of the second pass downward tapering flue and the inlet 50 of the third pass flue. The two side walls are symmetrical water-cooled walls to achieve complete combustion of unburned carbon.

[0050] The vertical flue 48 is located behind the three-pass upward flue 54. Its front wall is the rear wall of the three-pass flue and the front wall of the vertical flue, which share a water-cooled wall 43. Its rear wall is the rear wall of the vertical flue 47. The upper end is provided with a vertical flue flue gas outlet 51, which is used to guide the flue gas into the tail heating surface system.

[0051] General Technical Design Specification

[0052] The boiler body structure described in Embodiments 1 and 2 above can be adapted and designed based on the invention patent technology previously disclosed and authorized by the inventor; the auxiliary structures of the boiler, such as fuel inlet, desulfurizer inlet, slag discharge port, material replenishment inlet, primary air and secondary air inlet, furnace flue gas outlet, furnace door, explosion-proof door, observation hole, measuring hole, and maintenance hole, are all designed in accordance with the general technical standards of existing waste incineration boilers.

[0053] The boiler's furnace water-cooled wall tube water circulation system, flue water-cooled wall tube water circulation system, vertical shaft water-cooled wall tube water circulation system, as well as the steel frame structure, thermal insulation layer, superheater, reheater, economizer, air preheater, and other tail-end heating surfaces, all adopt existing mature boiler design technical standards. Among them, the upper part of the boiler drum of natural circulation steam boilers and power plant boilers is connected to the air guide pipe, and the lower part of the boiler drum is connected to the downcomer. All longitudinal and transverse lower headers are connected to their matching downcomers, and all longitudinal and transverse upper headers are connected to their matching air guide pipes. Hot water boilers, forced circulation steam boilers, and power plant boilers are all designed according to existing common and mature technologies.

[0054] Furthermore, the different structural features and components described in Examples 1 and 2 can be optimized and combined with each other according to actual application requirements to form new furnace structures, all of which fall within the protection scope of this invention.

[0055] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make various improvements and adjustments under the guidance of the present invention without departing from the spirit and scope of the claims, and these improvements and adjustments are all within the scope of protection of the present invention.

Claims

1. A multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler, characterized in that, It includes a furnace (main combustion chamber), main air chamber, auxiliary combustion chamber, second-pass flue, third-pass flue, auxiliary air chamber, water-cooled partition wall for guiding flue gas from bottom to top, a "pants-shaped" furnace (main combustion chamber), front main air chamber, rear main air chamber, high-temperature flue gas recirculation system, self-combustion method and intelligent control system; the "pants-shaped" furnace (main combustion chamber) is correspondingly configured with front and rear second-pass flue, front and rear third-pass flue and front and rear auxiliary air chamber.

2. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The furnace (main combustion chamber) 8 has a main air chamber 1 at its lower end, a water-cooled roof 13 at its upper end, a furnace front wall 5 on its front side, and a furnace rear wall 6 on its rear side; the auxiliary combustion chamber 53 has an auxiliary air chamber 3 at its lower end, and its upper end is connected to the outlet of the second-pass flue and the inlet of the third-pass flue; the upper ends of the second-pass flue 10 and the third-pass flue 52 are both equipped with water-cooled roofs 13, and their lower ends are both connected to the upper end of the auxiliary combustion chamber 53.

3. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The guide flue gas first moves downward and then upward. The front side of the water-cooled partition wall 11 is a two-pass downward gradually narrowing flue duct 10, and the rear side is a three-pass upward flue duct 52.

4. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The underside of the main combustion chamber 31 is provided with a front main air chamber 22, a rear main air chamber 23, and a water vapor cold sealing roof 38. The upper part of the front wall of the main combustion chamber 31 bends backward to form an extension section 32, and the upper part of the rear wall bends forward to form an extension section 45. The main combustion chamber 31 is equipped with a front auxiliary combustion chamber 55 and a rear auxiliary combustion chamber 56. The lower part of the front auxiliary combustion chamber 55 is provided with a front auxiliary air chamber 25, and the lower part of the rear auxiliary combustion chamber 56 is provided with a rear auxiliary air chamber 26. The upper part of the front auxiliary combustion chamber 55 is provided with a front second-pass flue outlet 28 and a front third-pass flue inlet 59, and the upper part of the rear auxiliary combustion chamber 56 is provided with a rear second-pass flue outlet 49 and a rear third-pass flue inlet 50.

5. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The front side of the water-cooled partition wall, where the front guide flue gas flows downward and then upward, is the first three-pass upward flue 29, and the rear side is the first two-pass downward gradually narrowing flue; the front side of the water-cooled partition wall, where the rear guide flue gas flows downward and then upward, is the last two-pass upward flue 53, and the rear side is the last three-pass downward gradually narrowing flue 54.

6. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The lower end of the front auxiliary combustion chamber 55 of the underpants furnace (main combustion chamber) 31 is provided with a front auxiliary air chamber 25, and the upper end is connected to the lower end of the front second-pass flue 32 and the front third-pass flue 29; the lower end of the rear auxiliary combustion chamber 56 of the underpants furnace (main combustion chamber) 31 is provided with a rear auxiliary air chamber 26, and the upper end is connected to the lower end of the rear second-pass flue 53 and the rear third-pass flue 54.

7. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The high-temperature superheater 33 is installed in the upper part of the first three passes of the flue gas in the underpants furnace, where there is no wear. The high-temperature superheater 44 is installed in the upper part of the last three passes of the flue gas in the underpants furnace, where there is no wear.

8. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The structure and operation of the high-temperature flue gas recirculation system are as follows: a high-temperature flue gas extraction port is opened at a predetermined position in the upper part of the third pass flue of the boiler to extract clean high-temperature flue gas with a temperature of 450℃~500℃; the clean high-temperature flue gas is transported to the lower part of the dense phase zone of the furnace through a high-temperature resistant pipeline to increase the temperature inside the furnace, enhance the combustion process, and suppress nitrogen oxides (NOx). x The high-temperature flue gas recirculation system is equipped with an intelligent regulating valve group and an oxygen concentration feedback control system. The oxygen concentration feedback control system adjusts the flue gas recirculation flow rate in real time to keep the temperature inside the furnace stable at ≥900℃.

9. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The operation process of the self-combustion method is as follows: During the boiler start-up stage, biomass, oil, or natural gas is used for external combustion assistance. When the temperature in the three-pass flue reaches 950°C, the external combustion assistance device is shut off, and the high-temperature flue gas recirculation system is started simultaneously. The boiler's self-combustion condition is maintained continuously through the stable operation of this system.

10. The multi-chamber high-temperature low-oxygen self-combustion fluidized bed waste incineration boiler according to claim 1, characterized in that, The intelligent control system integrates online monitoring sensors for bed temperature, oxygen concentration, furnace pressure, and flue gas composition to achieve real-time acquisition and transmission of core operating parameters. Based on AI algorithms, the system constructs a dynamic coupling model of "waste characteristics - air distribution strategy - flue gas circulation - combustion state". The model performs real-time analysis and calculation on the collected parameters and automatically adjusts the operating parameters of each actuator in the boiler to achieve fully automatic intelligent control of the entire boiler combustion process.

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