Pressurized oxycombustion furnace system

Abstract

This invention relates to the field of combustion technology and discloses a pressurized oxy-fuel combustion furnace system. The pressurized oxy-fuel combustion furnace system includes a furnace body, which comprises a furnace chamber, an air distribution plate, a gas chamber, a first air inlet, and a guide tube. The air distribution plate is located inside the furnace chamber and at its lower part. Multiple fluidizing nozzles are provided on the air distribution plate. The gas chamber is located below the air distribution plate and communicates with the multiple fluidizing nozzles. The first air inlet is located on the side wall of the furnace body and communicates with the gas chamber. The guide tube penetrates the gas chamber and the air distribution plate, with its upper end communicating with the furnace chamber and its lower end forming a second air inlet. The first and second air inlets are used to supply at least one gaseous medium to the furnace chamber, respectively, and the gaseous medium flowing through the air distribution plate can fluidize the solid materials in the furnace chamber. The pressurized oxy-fuel combustion furnace system of this invention can realize pressurized oxy-fuel combustion of gaseous and solid fuels under actual operating conditions, and achieve multi-channel supply and smooth switching of gaseous media.

Description

Technical Field

[0001] This invention belongs to the field of combustion technology, specifically relating to a pressurized oxygen-enriched combustion furnace system. Background Technology

[0002] Most pressurized oxygen-enriched combustion furnaces in related technologies are laboratory-scale devices, small in scale, and only used for small-sample fuel performance testing. They cannot simulate industrial conditions and have limited fuel compatibility, only able to burn one type of fuel, either solid or gaseous, resulting in poor fuel adaptability. Furthermore, there are shortcomings in the supply and switching between gaseous and solid materials during combustion. In addition, current research in related technologies focuses only on combustion characteristics and pollutant emissions, lacking research on core challenges such as heat transfer and heating surface arrangement. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a pressurized oxy-fuel combustion furnace system. This system enables pressurized oxy-fuel combustion of gaseous and solid fuels under actual operating conditions, achieves multi-channel supply and smooth switching of the gas medium, and, combined with a heat exchange system and a measurement system, realizes the measurement of the furnace's thermal parameters, providing data support for further design optimization.

[0004] The pressurized oxygen-enriched combustion furnace system of this invention includes a furnace body, which includes a furnace chamber, an air distribution plate, a gas chamber, a first air inlet, and a guide tube. The air distribution plate is disposed inside the furnace chamber and located at the lower part of the furnace chamber. The air distribution plate is provided with multiple fluidizing nozzles. The gas chamber is located below the air distribution plate and communicates with the multiple fluidizing nozzles. The first air inlet is disposed on the side wall of the furnace body and communicates with the gas chamber. The guide tube passes through the gas chamber and the air distribution plate. The upper end of the guide tube communicates with the furnace chamber, and the lower end of the guide tube forms a second air inlet. The first air inlet and the second air inlet are used to supply at least one gaseous medium to the furnace chamber, and the gaseous medium flowing through the air distribution plate can fluidize the solid materials in the furnace chamber.

[0005] The pressurized oxygen-enriched combustion furnace system in this embodiment, through its dual-inlet structure of an air distribution plate and a guide tube, enables the on-demand supply of different gas media. This satisfies the fluidization requirements of fluidized bed materials and provides flexible gas distribution paths for different combustion stages or modes. Furthermore, the guide tube directly penetrates the air distribution plate and connects to the furnace, forming an independent air inlet channel separate from the fluidizing air. This channel can generally be used to directly supply fuel gas, preventing premature mixing with the fluidizing air and promoting stable combustion within the furnace.

[0006] In some embodiments, the furnace body further includes a third air inlet located in the central region of the furnace body, the third air inlet being used to supply at least one of the gaseous media to the furnace chamber.

[0007] In some embodiments, the furnace body further includes a particulate material inlet, which communicates with the furnace chamber and is used to convey solid material into the furnace chamber, the solid material including at least one of solid fuel and bed material.

[0008] In some embodiments, the furnace body further includes a flue, on which a pressure regulating valve is provided. The pressure regulating valve is used to regulate the working pressure of the furnace chamber, and the working pressure regulation range of the furnace chamber is 0-1.6 MPa; and / or,

[0009] In some embodiments, the thermal power of the furnace body ranges from 50 to 200 kW.

[0010] In some embodiments, the space between the sidewall of the furnace chamber and the outer shell of the furnace body is filled with insulating material, and the air chamber is connected to the area where the insulating material is located, so that the pressure on the inner and outer sides of the sidewall of the furnace chamber is consistent.

[0011] In some embodiments, the pressurized oxygen-enriched combustion furnace system further includes a gas burner connected to the first air inlet. The gas burner serves as a channel for supplying gaseous media flowing through it into the furnace chamber, or the gas burner is used to burn the gaseous media flowing through it within the gas burner to heat the furnace chamber.

[0012] In some embodiments, the pressurized oxygen-enriched combustion furnace system includes multiple detection units arranged along the height of the furnace body, the detection units being used to detect the temperature and / or pressure of the furnace chamber.

[0013] In some embodiments, the pressurized oxygen-enriched combustion furnace system further includes a heat exchange system and a measurement system. The heat exchange system is connected to the furnace body and is used to transfer heat from different areas within the furnace. The measurement system is connected to the heat exchange system and the detection unit and is used to measure the thermal parameters of different areas within the furnace through the heat exchange system and the detection unit when the furnace is in stable combustion.

[0014] In some embodiments, the heat exchange system includes multiple heat exchangers, multiple heat exchange probes, and multiple coolers. The heat exchangers are placed inside the furnace body, and the heat exchange probes are disposed in the dense phase region, splash region, dilute phase region, and flue gas outlet region of the furnace body. The heat exchange probes have a U-shaped tube structure, and thermocouples for measuring the tube wall temperature are disposed on the tube wall of the heat exchange probes. The thermocouples are connected to the measurement system. The multiple heat exchangers and the multiple heat exchange probes are connected to the coolers through pipes so that the heat exchange medium in the coolers flows between the coolers, the heat exchangers, and the heat exchange probes.

[0015] This invention, through the design of the furnace structure, multiple air intakes, pressure control, gas burner, detection unit, and heat exchange and measurement system, achieves stable operation and flexible switching of oxygen-enriched combustion of gaseous and solid fuels under actual furnace pressures of 0-1.6 MPa. It can accurately measure thermodynamic parameters such as heat transfer coefficients at key locations such as the dense phase and dilute phase regions, providing direct and reliable experimental data support for solving the problem of heat transfer surface arrangement in pressurized oxygen-enriched combustion boilers, and accelerating the promotion of pressurized oxygen-enriched combustion in practical engineering. Attached Figure Description

[0016] Figure 1 This is an overall schematic diagram of the pressurized oxygen-enriched combustion furnace system according to an embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the heat exchange probe in an embodiment of the present invention.

[0018] Figure label: 1. Furnace body; 11. Furnace chamber; 12. Air distribution plate; 13. Gas chamber; 14. First air inlet; 15. Guide tube; 16. Fluidizing nozzle; 17. Second air inlet; 18. Third air inlet; 19. Particle material connection port; 110. Flue; 111. Pressure regulating valve; 2. Gas burner; 3. Detection unit; 4. Heat exchange system; 41. Heat exchanger; 42. Heat exchange probe; 43. Cooler; 421. Thermocouple; 5. Measurement system. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] like Figures 1-2As shown, the pressurized oxygen-enriched combustion furnace system of this invention includes a furnace body 1. The furnace body 1 includes a furnace chamber 11, an air distribution plate 12, a gas chamber 13, a first air inlet 14, and a guide tube 15. The air distribution plate 12 is located inside the furnace chamber 11 and at the lower part of the furnace chamber 11. The air distribution plate 12 is provided with a plurality of fluidizing nozzles 16. The gas chamber 13 is located below the air distribution plate 12 and communicates with the plurality of fluidizing nozzles 16. The first air inlet 14 is located on the side wall of the furnace body 1 and communicates with the gas chamber 13. The guide tube 15 passes through the gas chamber 13 and the air distribution plate 12. The upper end of the guide tube 15 communicates with the furnace chamber 11, and the lower end of the guide tube 15 forms a second air inlet 17. The first air inlet 14 and the second air inlet 17 are used to supply at least one gaseous medium to the furnace chamber 11 respectively, and the gaseous medium flowing through the air distribution plate 12 can fluidize the solid material in the furnace chamber 11.

[0021] The pressurized oxygen-enriched combustion furnace system of this invention, through the dual-inlet structure of the air distribution plate 12 and the guide tube 15, can achieve on-demand supply of different gas media. This satisfies the fluidization requirements of fluidized bed materials and provides flexible gas distribution paths for different combustion stages or modes. Furthermore, the guide tube 15 directly penetrates the air distribution plate 12 and connects to the furnace 11, forming an independent air inlet channel separate from the fluidizing air. This channel can generally be used to directly supply fuel gas, avoiding premature mixing with the fluidizing air and facilitating stable combustion within the furnace 11.

[0022] The furnace body 1 forms the main structure for pressurized oxygen-enriched combustion. The furnace chamber 11 is the combustion reaction space, with its diameter increasing from bottom to top. An air distribution plate 12 is arranged at the bottom inside the furnace chamber 11, and multiple fluidizing nozzles 16 are opened on the air distribution plate 12. Below the air distribution plate 12 is a sealed gas chamber 13, which is connected to the first air inlet 14 located on the side wall of the furnace body 1. This allows the gaseous medium (such as a mixture of oxygen and carbon dioxide, air, fuel gas, etc.) entering through the first air inlet 14 to be evenly distributed to each fluidizing nozzle 16 through the gas chamber 13 and sprayed upward into the furnace chamber 11, thereby achieving uniform dispersion of the airflow. Furthermore, when there is solid material above the air distribution plate 12, the solid material can be fluidized. The guide tube 15 is a vertical cylindrical structure that penetrates the gas chamber 13 and the air distribution plate 12. Its lower end extends out of the bottom of the furnace body 1 to form a second air inlet 17, and its upper end is open and placed inside the furnace chamber 11. The second air inlet 17 can be used to introduce another or the same gaseous medium, which is directly transported into the furnace 11 through the guide tube 15 without passing through the fluidizing nozzle 16 of the air distribution plate 12. By controlling the type, flow rate, and pressure of the medium at the first air inlet 14 and the second air inlet 17 respectively, the fuel gas and the combustion-supporting gas (such as a mixture of oxygen and carbon dioxide) can be fully mixed and combusted in the furnace 11. In addition, by controlling the combustion process and the pressure of the gaseous medium, the oxygen-enriched combustion requirements of gaseous or solid fuels under pressurized conditions can be met, and stable and adjustable combustion conditions can be provided for heat exchange experiments in the furnace 1.

[0023] In some embodiments, the furnace body 1 further includes a third air inlet 18, which is located in the central region of the furnace body 1 and is used to supply at least one gaseous medium to the furnace chamber 11.

[0024] The pressurized oxy-fuel combustion furnace system of this invention adds a third air inlet 18, increasing the gas supply path and enabling multi-stage, stratified gas supply. This inlet is located in the central region of the furnace body 1, allowing direct gas delivery into the central section of the furnace chamber 11, thereby flexibly adjusting the combustion atmosphere, temperature distribution, and pollutant generation within the furnace. For example, during pressurized oxy-fuel combustion, combustion-supporting gas can be supplemented through the third air inlet 18 to optimize combustion efficiency, achieve complete fuel combustion, and control emissions such as nitrogen oxides.

[0025] Typically, the third air inlet 18 is located on the side wall of the furnace body 1, at a height in the middle of the furnace chamber 11. The third air inlet 18 is connected to an external gas source via a pipe, allowing independent control of the type, flow rate, and pressure of the gas medium. The gas medium can be a mixture of oxygen and carbon dioxide, proportioned according to experimental requirements, for example, with oxygen accounting for 15%-30% by volume. During operation, the third air inlet 18 can serve as an auxiliary air intake path, working in conjunction with the first air inlet 14 and the second air inlet 17 to achieve zoned supply of the gas medium to the furnace chamber 11. For example, during gas combustion or pulverized coal combustion, introducing a portion of the mixed gas through the third air inlet 18 helps regulate the temperature in the middle of the furnace chamber 11, preventing localized overheating and ensuring complete combustion of the gaseous fuel or pulverized coal.

[0026] In some embodiments, the furnace body 1 further includes a particulate material inlet 19, which is connected to the furnace chamber 11 and is used to convey solid materials to the furnace chamber 11. The solid materials include at least one of solid fuel and bed material.

[0027] The pressurized oxygen-enriched combustion furnace system of this invention achieves continuous and controllable addition of solid materials under pressure by setting a particulate material connection port 19. This interface provides a dedicated conveying channel for solid fuels (such as coal particles or coal powder) and the bed material required for fluidized beds, enabling the system to maintain stable pressure inside the furnace while smoothly switching from gaseous fuel combustion to solid fuel combustion, or directly conducting solid fuel combustion experiments.

[0028] In some specific embodiments, the particulate material inlet 19 is located on the side wall of the furnace body 1 and connected to external feeders and other mechanical components. Under pressure, the solid material is precisely metered and conveyed into the furnace 11 by the feeder. Solid fuel mainly refers to combustibles such as coal particles or pulverized coal; the bed material consists of inert particles, such as sand and alumina, used to form a stable fluidized state and assist in heat transfer during fluidized bed combustion. Before conducting pressurized oxygen-enriched combustion experiments in a coal-fired fluidized bed, an appropriate amount of bed material must be filled into the air distribution plate 12 of the furnace 11 through this inlet. During the combustion stage, solid fuel is intermittently added to the furnace 11 through the same inlet in conjunction with the feeder.

[0029] In some specific embodiments, at least two pressurized chambers are typically connected in series and alternately transfer solid materials, and are fed in conjunction with a screw conveyor to allow the solid materials to enter the granular material inlet 19.

[0030] In some embodiments, the furnace body 1 further includes a flue 110, on which a pressure regulating valve 111 is provided. The pressure regulating valve 111 is used to regulate the working pressure of the furnace chamber 11. The working pressure regulation range of the furnace chamber 11 is 0-1.6MPa, and the thermal power range of the furnace body 1 is 50-200KW.

[0031] The pressurized oxy-fuel combustion furnace system of this invention, by incorporating a flue 110 with a pressure regulating valve 111, enables precise pressure control and stable operation over a wide pressure range (atmospheric pressure to 1.6 MPa), thereby simulating the operating conditions of an actual pressurized oxy-fuel combustion boiler. Simultaneously, the thermal power of the entire furnace body 1 ranges from 50 to 200 kW, ensuring a sufficient scale for the experimental setup to reflect the physicochemical characteristics of the real process compared to the smaller-scale furnace body 1 equipment in existing technologies. This provides more reliable data for the further promotion and implementation of the furnace body 1.

[0032] In practical use, the flue 110 is located at the flue gas outlet of the furnace 11, serving as a discharge channel for combustion products. A pressure regulating valve 111 (e.g., a back pressure valve) is installed on the flue 110. By adjusting the opening of this valve, the flow resistance of the entire system can be changed, thereby actively and precisely controlling the working pressure inside the furnace 11 at a target value, such as 0.1 MPa, 1.5 MPa, or up to 1.6 MPa, to meet the needs of pressurized oxygen-enriched combustion experiments at different pressure levels. During experiments, by controlling the input amount of solid or gaseous fuel and correspondingly adjusting the flow rate of the combustion-supporting gas, the total combustion heat release power can be stabilized at any specific value within this range, such as 80 kW or 150 kW, thus meeting the needs of combustion and heat exchange studies under different heat loads.

[0033] In some embodiments, the space between the sidewall of the furnace chamber 11 and the outer shell of the furnace body 1 is filled with insulation material, and the gas chamber 13 is connected to the area where the insulation material is located, so that the pressure on the inner and outer sides of the sidewall of the furnace chamber 11 is consistent.

[0034] This embodiment cleverly establishes pressure balance on both the inner and outer sides of the sidewall of the furnace chamber 11 (i.e., the inner wall of the combustion chamber) by connecting the gas chamber 13 with the insulation material area within the interlayer of the furnace body 1. This design allows the sidewall of the furnace chamber 11 to primarily bear temperature loads during system pressurization, while bearing almost no mechanical stress generated by the internal and external pressure difference. This significantly reduces the structural strength requirements and manufacturing costs of the sidewall of the furnace chamber 11, and improves the long-term operational safety and reliability of the system under high-pressure conditions.

[0035] Specifically, a certain gap exists between the outer metal sidewall of the furnace 11 and the steel outer shell of the furnace body 1, and this gap is filled with high-temperature resistant thermal insulation material. The gas chamber 13 located below the air distribution plate 12 is not completely sealed; its sidewalls or top have channels or gaps that connect the thermal insulation material-filled gap spaces. The working pressure (high-pressure gas medium) inside the furnace 11 is transmitted to the gap area where the thermal insulation material is located through the gas chamber 13. The amount of gas medium in the gap is small, and the gas chamber 13 mainly provides combustion-supporting gas in the later stages, which can prevent combustion in the gap space. In some specific embodiments, the area where the thermal insulation material is located is a separate sealed area isolated from the gas chamber 13 and the furnace 11, and is directly connected to the combustion-supporting gas supply system through a pipeline. This further ensures that the gas medium in the gap does not burn.

[0036] Through the design of this embodiment, the inner surface of the furnace 11 sidewall bears the pressure inside the furnace 11, while its outer surface bears almost the same pressure through the gas in the interlayer, thus achieving pressure balance on both sides. Simultaneously, the insulation material effectively reduces heat loss from the furnace 11 to the outer shell, keeping the outer shell temperature at a low level (e.g., not exceeding 50°C). This pressure balance design is particularly suitable for pressurized oxygen-enriched combustion environments with operating pressures up to 1.6 MPa, effectively preventing deformation or damage to the furnace 11 sidewall due to excessive pressure differential.

[0037] In some embodiments, the pressurized oxygen-enriched combustion furnace system further includes a gas burner 2, which is connected to a first air inlet 14. The gas burner 2 serves as a channel for supplying the gas medium flowing through it into the furnace chamber 11, or it serves to burn the gas medium flowing through it to heat the furnace chamber 11. The pressurized oxygen-enriched combustion furnace system also includes multiple detection units 3, which are arranged along the height of the furnace body 1. The detection units 3 are used to detect the temperature and / or pressure of the furnace chamber 11.

[0038] The pressurized oxygen-enriched combustion furnace system of this invention introduces a gas burner 2 and a multi-point detection unit 3 arranged along the height of the furnace body 1, enabling the system to have preheating and combustion modes, with the combustion mode switchable. It also possesses operational condition monitoring capabilities. The gas burner 2 can both ignite and heat the furnace and act as a gas passage, saving on piping layout, and allowing for seamless transition of gas supply from preheating to different combustion stages. The detection unit 3 can detect the temperature and pressure field distribution along the height direction inside the furnace 11, providing data reference for judging combustion stability, pressure status, and subsequent heat exchange experimental data analysis.

[0039] Specifically, the outlet of the gas burner 2 is directly or via a pipe connected to the first inlet 14 of the furnace body 1. During the preheating stage, the burner receives fuel gas (such as natural gas, propane, dimethyl ether, etc.) and combustion-supporting gas (air or a mixture of oxygen and carbon dioxide), usually air, which is more economical. High-temperature flue gas is generated through combustion within the gas burner 2. The high-temperature flue gas enters the furnace 11 through the first inlet 14, the gas chamber 13, and the air distribution plate 12, thereby heating the furnace 11 and the bed material (if any) to above the ignition temperature of the fuel.

[0040] Once the furnace 11 enters a stable combustion state, the supply of gaseous fuel to the gas burner 2 can be stopped. At this point, without gaseous fuel, the gas burner 2 simply acts as a gas passage, delivering the external mixed gas to the furnace 11. This achieves a seamless transition from preheating to combustion.

[0041] Multiple detection units 3, such as temperature sensors and pressure sensors, are arranged at intervals along the height of the furnace body 1 from the bottom of the furnace 11 to the flue gas outlet. For example, detection points can be set in characteristic areas such as the dense phase zone, splash zone, dilute phase zone, and outlet flue 110. These detection units 3 collect temperature and pressure signals at each location in real time and transmit them to the control system or computer to analyze the combustion situation inside the furnace body 1.

[0042] In some embodiments, the pressurized oxygen-enriched combustion furnace system further includes a heat exchange system 4 and a measurement system 5. The heat exchange system 4 is connected to the furnace body 1 and is used to transfer heat from different areas within the furnace chamber 11. The measurement system 5 is connected to the heat exchange system 4 and the detection unit 3 and is used to measure the thermal parameters of different areas within the furnace chamber 11 through the heat exchange system 4 and the detection unit 3 when the furnace chamber 11 is in stable combustion.

[0043] The heat exchange system 4 includes multiple heat exchangers 41, multiple heat exchange probes 42, and multiple coolers 43. The heat exchangers 41 are placed inside the furnace body 1. The heat exchange probes 42 are located in the dense phase zone, splash zone, dilute phase zone, and flue gas outlet zone of the furnace body 1. The heat exchange probes 42 have a U-shaped tube structure. Thermocouples 421 for measuring the tube wall temperature are installed on the tube wall of the heat exchange probes 42. Thermocouples 421 are connected to the measurement system 5. The multiple heat exchangers 41 and multiple heat exchange probes 42 are connected to the coolers 43 through pipes so that the heat exchange medium in the coolers 43 flows between the coolers 43, the heat exchangers 41, and the heat exchange probes 42.

[0044] The pressurized oxy-fuel combustion boiler system of this invention integrates a heat exchange system 4 and a measurement system 5 to directly measure the thermal parameters of typical areas within the furnace 11, especially the heat exchange system 4. The heat exchange system 4 not only transfers heat and maintains stable furnace temperature, but also includes a heat exchange probe 42 that acts as a sensor to measure heat exchange data in different areas during combustion. The measurement system 5 collaboratively processes the data from the heat exchange probe 42 and the detection unit 3, ultimately obtaining key thermal parameters (such as the local heat transfer coefficient) crucial for the design of the pressurized oxy-fuel combustion boiler. This solves the technical problem in related technologies where simulated operating conditions using hot-bed cold-tube or heat-pipe cold-bed systems fail to accurately reflect the heat transfer characteristics in the actual combustion environment.

[0045] Specifically, the heat exchange system 4 includes: multiple tubular or wall-mounted heat exchangers 41 arranged at different locations within the furnace 11, used to maintain the overall thermal balance of the furnace 11 and achieve functions such as heat output; multiple specially designed U-shaped tubular heat exchange probes 42, which are inserted into typical locations in the dense phase zone, splash zone, dilute phase zone, and flue gas outlet zone of the furnace 11, simulating the heat-receiving surfaces arranged in these areas; and an external cooler 43, such as a circulating water cooling device, an air cooler 43, or other heat exchanger equipment or heat exchange system, which uses a heat exchange medium (which can be water, air, carbon dioxide, or nitrogen) to cool in the cooler 43, and then is driven by a pump to flow through the heat exchangers 41 and heat exchange probes 42 arranged in parallel or series, absorbing heat before returning to the cooler 43, forming a circulating cooling loop. Alternatively, a single-pass, non-circulating direct-current cooling method can be used, continuously supplying a heat exchange medium, such as cooling water, to the cooler 43, heat exchanger 41, and heat exchange probe 42, and then using the output hot heat exchange medium for other equipment. Each heat exchange probe 42 consists of symmetrically arranged inlet and outlet pipes, made of high-temperature resistant metal tubing. Mounting grooves are machined at intervals along the length of the tube wall, and thermocouples 421 are embedded in these grooves to measure the temperature of the metal tube wall at that location.

[0046] Once the furnace 11 enters a stable combustion state, the measurement system 5 records and reads the following data: the temperature of the heat exchange medium at the inlet (Tin), the temperature of the heat exchange medium at the outlet (Tout), and the flow rate of the heat exchange medium for each heat exchange probe 42, as well as the pressure and temperature data inside the furnace 11. The calculation module built into the measurement system 5 can calculate the local heat transfer coefficient at the probe's location under the current combustion conditions based on this data and the probe's geometric parameters.

[0047] In some specific embodiments, the flow rate of the medium in each heat exchanger 41 and each heat exchange probe 42 can be adjusted independently, so as to flexibly control the cooling intensity of each measurement point, simulate different heat exchange intensities, and obtain more experimental data.

[0048] The following describes the experimental method of the pressurized oxygen-enriched combustion furnace according to an embodiment of the present invention. The experimental method of the pressurized oxygen-enriched combustion furnace according to any of the above embodiments is implemented using the pressurized oxygen-enriched combustion furnace system, including a preheating step, a gas combustion step, and a solid combustion step.

[0049] Preheating step: fuel gas and air are supplied to the gas burner 2 through the first air inlet 14 so that the fuel gas and air burn in the gas burner 2 and preheat the furnace 11 until the furnace 11 reaches the preheating temperature, and then the supply of fuel gas to the gas burner 2 is stopped.

[0050] Gas combustion steps: fuel gas is supplied to the furnace 11 through the second air inlet 17, the air supply in the preheating step is gradually stopped, and a mixture of oxygen and carbon dioxide is supplied to the gas burner 2 through the first air inlet 14. The mixture can be supplied to the furnace 11 through the gas burner 2 so that the fuel gas and the mixture can burn stably in the furnace 11.

[0051] Solid combustion step: The fuel gas supplied to the furnace 11 is gradually stopped through the second air inlet 17, and solid fuel is supplied to the furnace 11 through the particulate material connection port 19 so that the solid fuel and the mixed gas can burn stably in the furnace 11.

[0052] In some embodiments, the pressurized oxygen-enriched combustion furnace experimental method further includes a parameter measurement step: under stable combustion conditions in the gas combustion step or solid combustion step, the thermal parameters of different regions in the furnace 11 are measured by the measurement system 5.

[0053] In some embodiments, the pressurized oxygen-enriched combustion furnace experimental method further includes a preparatory step: when the solid fuel is coal particles, before the preheating step, bed material is introduced into the furnace 11 through the particle material inlet 19.

[0054] In some embodiments, during the gas combustion step and the solid combustion step, the working pressure of the furnace 11 is adjusted by the pressure regulating valve 111 so that the interior of the furnace 11 is maintained at the target pressure and combustion is stable.

[0055] In some embodiments, during a stable combustion state in the gas combustion step or the solid combustion step, a mixed gas is supplied to the furnace 11 through the third air inlet 18.

[0056] The pressurized oxy-fuel combustion furnace experimental method of this invention achieves a smooth transition from safe system ignition and start-up to stable combustion of gaseous fuels and finally to stable combustion of solid fuels (coal particles or pulverized coal) through three steps: preheating, gas combustion, and solid combustion. This method also includes key operations such as pressure regulation, auxiliary air intake (third air inlet 18), and thermodynamic parameter measurement. This allows the experimental process to simulate real pressurized oxy-fuel combustion conditions at different pressures within the range of 0-1.6 MPa. Furthermore, under stable actual combustion conditions, it allows direct measurement of key thermodynamic parameters such as heat transfer coefficients at typical locations within the furnace 11, including the dense phase region and splash zone. This provides valuable actual furnace experimental data for the design and optimization of the heating surface of pressurized oxy-fuel combustion boilers.

[0057] First, depending on the experimental objective (fluidized bed combustion or pulverized coal combustion), the preparatory steps can be performed: if a coal-fired fluidized bed experiment is to be conducted, an appropriate amount of inert bed material should be added in advance through the particulate material connection port 19 to the air distribution plate 12 of the furnace 11.

[0058] Then, a preheating step is performed. The gas burner 2 is started, and fuel gas (such as natural gas or propane) and compressed air are introduced and ignited. The resulting high-temperature flue gas enters the furnace 11 through the first air inlet 14, the gas chamber 13, and the air distribution plate 12, preheating the furnace 11 and the bed material (if any) to above the ignition point of the fuel gas (e.g., 400-800°C). After preheating is completed, the supply of fuel gas to the gas burner 2 is stopped.

[0059] Next, the gas combustion step begins: the second air inlet 17 is opened, directly introducing fuel gas into the furnace 11. Simultaneously, the gas supplied to the gas burner 2 is switched to a predetermined ratio of oxygen and carbon dioxide mixture, and the air supply is gradually cut off. At this time, the gas burner 2 acts as a conduit for the mixed gas, sending it into the furnace 11 for combustion support. By adjusting the flow rates of each gas and the pressure regulating valve 111 of the flue 110, stable oxygen-enriched combustion of the gaseous fuel is achieved in the furnace 11 at a target pressure (e.g., 1.5 MPa). During this period, a portion of the mixed gas can be simultaneously supplied through the third air inlet 18 to adjust the combustion state within the furnace.

[0060] Finally, in the solid combustion step: based on the stable combustion of gaseous fuel, solid fuel (coal particles or pulverized coal) is added through the particulate material inlet 19, while the gaseous fuel supplied through the second air inlet 17 is gradually reduced and eventually stopped. By coordinating the solid feed rate, the mixed gas supply, and the pressure regulating valve 111, the system transitions to and maintains a stable state of pressurized oxygen-enriched combustion of solid fuel at the target pressure.

[0061] At any stable stage of gas combustion or solid combustion, the parameter measurement steps can be performed: start the measurement system 5 and the heat exchange system 4, adjust the cooling medium flow rate of each heat exchange probe 42 to a stable state, the system automatically collects and records the temperature and pressure data at each point, calculates the real-time heat transfer coefficient of different regions, and completes the measurement of heat transfer characteristics under actual furnace conditions.

[0062] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0064] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0065] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0066] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0067] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A pressurized oxygen-enriched combustion furnace system, characterized in that, Includes a furnace body (1), said furnace body (1) comprising: Furnace (11); Air distribution plate (12), the air distribution plate (12) is located inside the furnace (11) and at the lower part of the furnace (11), and the air distribution plate (12) is provided with multiple fluidizing nozzles (16). Air chamber (13), the air chamber (13) is located below the air distribution plate (12) and communicates with the plurality of fluidizing nozzles (16); The first air inlet (14) is located on the side wall of the furnace body (1) and communicates with the air chamber (13); The guide tube (15) passes through the gas chamber (13) and the air distribution plate (12). The upper end of the guide tube (15) is connected to the furnace (11), and the lower end of the guide tube (15) forms a second air inlet (17). The first air inlet (14) and the second air inlet (17) are used to supply at least one gaseous medium to the furnace (11) respectively, and the gaseous medium flowing through the air distribution plate (12) can fluidize the solid material in the furnace (11).

2. The pressurized oxygen-enriched combustion furnace system according to claim 1, characterized in that, The furnace body (1) also includes a third air inlet (18), which is located in the middle region of the furnace body (1) and is used to supply at least one gaseous medium to the furnace chamber (11).

3. The pressurized oxygen-enriched combustion furnace system according to claim 1, characterized in that, The furnace body (1) also includes a particulate material inlet (19), which is connected to the furnace chamber (11) and is used to convey solid materials to the furnace chamber (11). The solid materials include at least one of solid fuel and bed material.

4. The pressurized oxygen-enriched combustion furnace system according to claim 1, characterized in that, The furnace body (1) further includes a flue (110), on which a pressure regulating valve (111) is provided. The pressure regulating valve (111) is used to regulate the working pressure of the furnace (11), and the working pressure regulation range of the furnace (11) is 0-1.6 MPa; and / or The thermal power range of the furnace body (1) is 50-200KW.

5. The pressurized oxygen-enriched combustion furnace system according to claim 1, characterized in that, The side wall of the furnace chamber (11) is filled with heat-insulating material between it and the outer shell of the furnace body (1). The air chamber (13) is connected to the area where the heat-insulating material is located, so that the pressure on the inner and outer sides of the side wall of the furnace chamber (11) is consistent.

6. The pressurized oxygen-enriched combustion furnace system according to any one of claims 1-5, characterized in that, Also includes: A gas burner (2) is connected to the first air inlet (14). The gas burner (2) is used as a channel to supply the gas medium flowing through it into the furnace (11), or the gas burner (2) is used to burn the gas medium flowing through it in the gas burner (2) to heat the furnace (11).

7. The pressurized oxygen-enriched combustion furnace system according to claim 6, characterized in that, Also includes: Multiple detection units (3) are arranged along the height direction of the furnace body (1), and the detection units (3) are used to detect the temperature and / or pressure of the furnace chamber (11).

8. The pressurized oxygen-enriched combustion furnace system according to claim 7, characterized in that, Also includes: A heat exchange system (4) is connected to the furnace body (1) and is used to transfer heat from different areas within the furnace chamber (11). The measurement system (5) is connected to the heat exchange system (4) and the detection unit (3) and is used to measure the thermal parameters of different areas in the furnace (11) through the heat exchange system (4) and the detection unit (3) when the furnace (11) is burning stably.

9. The pressurized oxygen-enriched combustion furnace system according to claim 8, characterized in that, The heat exchange system (4) includes: Multiple heat exchangers (41) are placed inside the furnace body (1); Multiple heat exchange probes (42) are provided in the dense phase region, splash region, dilute phase region and flue gas outlet region of the furnace body (1). The heat exchange probes (42) are U-shaped tube structures. Thermocouples (421) for measuring the tube wall temperature are provided on the tube wall of the heat exchange probes (42). Thermocouples (421) are connected to the measurement system (5).

10. The pressurized oxygen-enriched combustion furnace system according to claim 9, characterized in that, The heat exchange system (4) also includes multiple coolers (43), and multiple heat exchangers (41) and multiple heat exchange probes (42) are connected to the coolers (43) through pipes so that the heat exchange medium in the cooler (43) flows between the cooler (43), the heat exchangers (41) and the heat exchange probes (42).

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