A system for coupling a flue gas driven SRF with a coal-fired delivery boiler
Patent Information
- Application Number
- CN202522395795.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-12
- Publication Date
- 2026-10-30
- Estimated Expiration
- 2035-11-12
AI Technical Summary
但SRF直接应用于燃煤锅炉尚不可行，需对现有的锅炉系统进行昂贵的改造
[0015]1、本实用新型系统利用锅炉产生的烟气作为动力，驱动粉状燃煤和SRF混合燃料输送至炉膛进行燃烧，保证了燃料安全性的同时实现了废热能源回收，从而减少了对外部气源的依赖，有助于减少运行期间的额外气源消耗，进而降低整体的运营成本，还能够有效提高SRF与燃煤锅炉耦合系统热效率和环保性能。
Smart Images
Figure CN224920443U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of coal-fired boiler technology, and more specifically, to a coupling system suitable for flue gas driven SRF and coal conveying boiler. Background Technology
[0002] Solid recoverable fuel (SRF), as an alternative fuel, is produced primarily from combustible solid waste (non-hazardous waste) in municipal solid waste through single or combined processes. The use of SRF can reduce dependence on fossil fuels and lower waste treatment costs and environmental impact. However, due to its low calorific value and poor combustion stability, SRF is mostly used as supplementary fuel.
[0003] Coal-fired boilers generate flue gas during operation, which contains a large amount of thermal and kinetic energy. Its recovery and utilization are of great value. Using boiler flue gas to drive fuel transportation can not only ensure fuel safety and prevent spontaneous combustion, but also preheat the fuel to a certain extent and improve the efficiency of the SRF coupled system with the coal-fired boiler. However, existing flue gas energy recovery technologies are often complex and expensive.
[0004] With the increasingly stringent trend of energy conservation and emission reduction, high-efficiency and low-pollution coal-fired boilers are essential. Coupling SRF (Superficial Flame Reduction) with a coal-fired boiler, and then thoroughly mixing it before combustion, is beneficial for the low-carbon development and clean transformation of coal-fired boilers. It also improves the efficiency of co-combustion of coal and SRF while ensuring combustion stability in the furnace, and facilitates the resource-based and harmless recycling of combustible solid waste. However, direct application of SRF to coal-fired boilers is not yet feasible, requiring costly modifications to existing boiler systems. Therefore, to better couple SRF with coal-fired boilers and achieve energy conservation and carbon reduction, a readily adaptable and highly efficient coal-fired boiler coupling technology is needed. Utility Model Content
[0005] In view of this, and in view of the shortcomings of the prior art, this utility model proposes a coupling system for flue gas driven SRF and coal conveying boiler, which can take into account both the fuel conveying driven by flue gas and the mixing uniformity of SRF and coal.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] A flue gas driven steam conveying pipeline (SRF) coupled with a coal-fired conveying boiler includes a boiler, a flue gas driven conveying pipeline, a first branch, a second branch, a mixing chamber, and a screw conveyor. The boiler has a furnace and a flue. The flue outlet is connected to the flue gas inlet of the flue gas driven conveying pipeline via a fan, and the flue gas outlet at the other end of the flue gas driven conveying pipeline is connected to the furnace. A first exhaust port, a second exhaust port, and a feed port are sequentially formed on the side wall of the flue gas driven conveying pipeline along the flue gas conveying direction. The first exhaust port is connected to the inlet end of the first branch, and the outlet end of the first branch is connected to the mixing chamber via a blower. The lower side of the mixing chamber is connected; the second exhaust port is connected to the air inlet of the second branch, and the other end of the second branch is the feed inlet; SRF powder and coal powder are mixed in the mixing chamber, the discharge port of the mixing chamber is connected to the feed inlet of the screw conveyor, one end of the discharge port of the screw conveyor extends into the second branch, and the discharge port of the screw conveyor faces downwards corresponding to the feed inlet below, and an air inlet of the screw conveyor is also provided above the screw conveyor opposite to the discharge port of the screw conveyor; the flue gas passes sequentially through the air inlet of the screw conveyor, the discharge port of the screw conveyor, and the feed inlet in the second branch.
[0008] Preferably, a flue gas denitrification device is also installed at the flue of the boiler, and the outlet of the flue gas denitrification device is connected to the fan through a corresponding flue gas pipeline.
[0009] Preferably, the system for coupling flue gas driven SRF with a coal-fired boiler further includes a fuel transport device, a fuel crushing device, and a feed hopper. The outlet of the fuel transport device is connected to the fuel crushing device, and the outlet of the fuel crushing device is connected to the feed hopper. The lower outlet of the feed hopper is connected to the mixing chamber inlet located above the mixing chamber. Two sets of the fuel transport device, the fuel crushing device, and the feed hopper are provided. Two mixing chamber inlets are provided, namely an SRF powder inlet and a coal powder inlet. A drive shaft is installed inside the mixing chamber, and several stirring blades are installed on the drive shaft. The stirring blades are driven by the drive shaft to rotate and stir. The mixing chamber outlet is located at the bottom of the mixing chamber.
[0010] Preferably, the blowpipe is inclined relative to the horizontal plane and the blowing direction is upward.
[0011] Preferably, the angle between the blow pipe and the horizontal plane is 20° to 40°.
[0012] Preferably, a plurality of the blowpipes are installed at equal intervals along the circumference of the lower outer wall of the mixing chamber, and all the blowpipes are connected to the first branch.
[0013] Preferably, the flue gas driven conveying pipe located between the second exhaust port and the feed port is designed as a pipe diameter changing section, wherein the cross-sectional area of the pipe diameter changing section first decreases and then increases in the direction from the second exhaust port to the feed port.
[0014] Compared with existing technologies, the present invention provides a coupling system for flue gas driven SRF and coal-fired conveying boilers with the following advantages:
[0015] 1. This utility model system uses the flue gas generated by the boiler as power to drive the pulverized coal and SRF mixed fuel to the furnace for combustion. It ensures fuel safety while realizing waste heat energy recovery, thereby reducing dependence on external gas sources, helping to reduce additional gas consumption during operation, and thus reducing overall operating costs. It can also effectively improve the thermal efficiency and environmental performance of the SRF and coal-fired boiler coupling system.
[0016] 2. This utility model system fully mixes pulverized coal and SRF in a mixing chamber according to a certain ratio before feeding it into the boiler furnace for combustion, which is conducive to achieving low carbon and clean coal-fired boilers and realizing the resource-based and harmless recycling of combustible solid waste.
[0017] 3. In this system, after the flue gas enters the flue gas drive conveying pipeline via the fan, a portion of the flue gas is guided to the injection pipe through the first branch and then injected into the mixing chamber. The injection pipe injects flue gas into the mixing chamber, which enhances turbulence and helps to promote a certain proportion of pulverized coal and SRF fuel to mix thoroughly during fuel conveying. This keeps the pulverized coal and SRF fuel in a loose state within the mixing chamber, ensuring the consistency and stability of fuel flow. Simultaneously, it avoids compaction of the pulverized coal and SRF fuel mixture, which could affect the feeding process, thereby enhancing the overall system reliability.
[0018] 4. In this utility model system, after the flue gas enters the flue gas driven conveying pipeline through the fan, a portion of the flue gas is also conveyed through the second branch to the discharge end of the screw conveyor via the air inlet of the screw conveyor. This allows the flue gas to drive the conveying of pulverized coal and SRF mixed fuel into the flue gas driven conveying pipeline, while preventing fuel from clogging the pipeline and thus avoiding affecting the stability of the system operation.
[0019] 5. In this utility model system, the flue gas driven conveying pipeline is designed with a variable section, which optimizes the flue gas flow characteristics.
[0020] 6. This utility model system is applicable to coal-fired boilers that co-fire SRF, without changing the structure of the coal-fired boiler itself. It is simple and reliable in design and has low operating costs. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the overall structure of a flue gas driven SRF coupled with a coal-fired boiler according to the present invention.
[0023] Figure 2 This is a schematic diagram of the internal structure of the mixing chamber in a flue gas driven SRF coupled system with a coal-fired boiler, according to the present invention.
[0024] In the diagram: 1-Boiler, 2-Flue gas driven conveying pipeline, 3-First branch, 4-Second branch, 5-Mixing bin, 6-Screw conveyor, 7-Flue gas inlet, 8-Flue gas outlet, 9-First exhaust port, 10-Second exhaust port, 11-Feed inlet, 12-Pulse jet pipe, 13-Screw conveyor air inlet, 14-Flue gas denitrification device, 15-Furnace, 16-Flue duct, 17-Fan, 18-Fuel transport device, 19-Fuel crushing device, 20-Feed hopper, 21-Drive shaft, 22-Agitator blades, 23-Mixing bin feed inlet, 24-Mixing bin discharge outlet. Detailed Implementation
[0025] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.
[0026] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not 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 utility model.
[0027] 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 one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0028] Example:
[0029] like Figure 1 As shown in the figure, this embodiment is a coupling system for flue gas driven SRF and coal-fired conveying boiler, including boiler 1, flue gas driven conveying pipeline 2, first branch 3, second branch 4, mixing chamber 5 and screw conveyor 6.
[0030] The boiler 1 has a furnace 15 and a flue 16. The flue outlet of the flue 16 is connected to the flue gas inlet 7 of the flue gas drive conveying pipe 2 via a fan 17. The flue gas outlet 8 at the other end of the flue gas drive conveying pipe 2 is connected to the furnace 15.
[0031] In this embodiment, the flue gas driven conveying pipe 2 uses the flue gas drawn from the flue 16 to transport pulverized coal and RHF mixed fuel into the furnace 15 for combustion, which improves the high efficiency of coal and SRF mixed combustion while ensuring the combustion stability of the furnace.
[0032] The side wall of the flue gas driven conveying pipeline 2 is provided with a first exhaust port 9, a second exhaust port 10 and a feed port 11 in sequence along the flue gas conveying direction.
[0033] The first exhaust port 9 is connected to the air inlet of the first branch 3, and the air outlet of the first branch 3 is connected to the lower side of the mixing chamber 5 through the blow pipe 12.
[0034] In other words, after the flue gas enters the flue gas drive conveying pipe 2 via the blower 17, a portion of the flue gas is guided to the injection pipe 12 through the first branch 3, and then injected into the mixing chamber 5. The injection pipe 12 injects flue gas into the mixing chamber 5, which can enhance the turbulence and help to promote the full mixing of a certain proportion of pulverized coal and SRF fuel during fuel transportation. This keeps the pulverized coal and SRF fuel in a loose state within the mixing chamber 5, ensuring the consistency and stability of fuel flow. At the same time, it avoids compaction of the pulverized coal and SRF fuel mixture, which would affect the feeding, thereby enhancing the operational reliability of the entire system.
[0035] The second exhaust port 10 is connected to the air inlet of the second branch 4, and the other end of the second branch 4 is the feed inlet 11. SRF powder and coal powder are mixed in the mixing chamber 5. The discharge port 24 of the mixing chamber is connected to the feed inlet of the screw conveyor 6. One end of the discharge port of the screw conveyor extends into the second branch 4, and the discharge port of the screw conveyor faces downwards, corresponding to the feed inlet 11 below. The upper part of the screw conveyor 6 is also provided with a screw conveyor air inlet 13 opposite to the discharge port of the screw conveyor. The flue gas passes through the screw conveyor air inlet 13, the screw conveyor discharge port, and the feed inlet 11 in the second branch 4 in sequence, helping the screw conveyor 6 to transport the fuel in the mixing chamber 5 to the flue gas drive conveying pipeline 2.
[0036] In other words, after the flue gas enters the flue gas driven conveying pipeline 2 through the fan 17, a portion of the flue gas is transported through the second branch 4 to the discharge end of the screw conveyor via the screw conveyor inlet 13, so that the flue gas drives the conveying of pulverized coal and SRF mixed fuel into the flue gas driven conveying pipeline 2, while preventing fuel from clogging the pipeline so as not to affect the stability of the system operation.
[0037] The above configuration in this embodiment allows the system to use the flue gas generated by the boiler as the power source for transporting pulverized coal and SRF mixed fuel, thereby reducing dependence on external gas sources, helping to reduce additional gas consumption during operation, and thus reducing overall operating costs.
[0038] In a further specific embodiment, a flue gas denitrification device 14 for removing nitrogen oxides from the combustion flue gas is also installed at the flue 16 of the boiler 1, and the outlet of the flue gas denitrification device 14 is connected to the fan 17 through a corresponding flue gas pipeline.
[0039] In a further specific embodiment, the system for coupling flue gas driven SRF with a coal-fired boiler also includes a fuel transport device 18, a fuel pulverizing device 19, and a feed hopper 20. The outlet of the fuel transport device 18 is connected to the fuel pulverizing device 19, and the outlet of the fuel pulverizing device 19 is connected to the feed hopper 20. The lower outlet of the feed hopper 20 is connected to the mixing chamber inlet 23 located above the mixing chamber 5. In this embodiment, there are two sets of the fuel transport device 18, the fuel pulverizing device 19, and the feed hopper 20, and two mixing chamber inlets 23 are also provided, namely an SRF powder inlet and a coal powder inlet.
[0040] The fuel transport device 18 is used to transport coal and SRF raw materials; the fuel crushing device 19 crushes the coal and SRF transported by the fuel transport device 18 into powder; the feed hopper 20 is connected to the fuel crushing device 19 and is used to transport and store the powdered coal and SRF.
[0041] like Figure 2As shown, a drive shaft 21 is installed inside the mixing chamber 5, and several stirring blades 22 are installed on the drive shaft 21. The stirring blades 22 are driven by the drive shaft 21 to rotate and stir. A mixing chamber outlet 24 is provided at the bottom of the mixing chamber 5.
[0042] The powdered RHF and coal pulverized by the fuel pulverizer 19 are fed into the mixing chamber 5 in proportion. The mixing chamber 5 uses the stirring blades 22 to fully mix the powdered coal and SRF. Then the powdered coal and SRF mixed fuel are discharged through the discharge port 24 of the mixing chamber.
[0043] In a further specific embodiment, the injection pipe 12 is inclined relative to the horizontal plane and the injection direction is upward. This allows the airflow to stir the fuel upward when it enters the mixing chamber 5 through the injection pipe 12, maintaining the loose state of the pulverized coal and SRF fuel, preventing them from being too compacted, and avoiding compaction of the pulverized coal and SRF mixed fuel, which would affect the feeding.
[0044] Furthermore, the angle between the injection pipe 12 and the horizontal plane is 20° to 40°, thereby optimizing the injection direction and force of the airflow, effectively promoting the mixing of pulverized coal and SRF fuel in the mixing chamber 5, ensuring that the fluffiness of the fuel is in an ideal state, and thus improving the operating efficiency and reliability of the system.
[0045] Furthermore, several blow pipes 12 are installed at equal intervals along the circumference of the lower outer wall of the mixing chamber, and all blow pipes 12 are connected to the first branch 3.
[0046] Multiple injection pipes 12 are arranged in a ring to inject airflow into the mixing chamber 5, which can ensure uniform airflow and achieve full coverage, avoiding the compaction and blockage of pulverized coal and SRF fuel caused by corner accumulation.
[0047] Through the synergistic effect of these injection pipes 12, the system can more efficiently mix and transport pulverized coal and SRF fuel, ensuring their full utilization during combustion, thereby improving the overall performance and efficiency of the system while reducing maintenance and operational risks.
[0048] In a further specific embodiment, the flue gas driven conveying pipe 2 located between the second exhaust port 10 and the feed port 11 is designed as a pipe diameter changing section, the cross-sectional area of which first decreases and then increases from the second exhaust port to the feed port.
[0049] The cross-sectional area of the pipe in the diameter-changing section decreases and then increases from the second exhaust port to the feed port. This can increase the kinetic energy of the flue gas in the flue gas driven conveying pipe 2, help the flue gas to fully mix with pulverized coal and SRF mixed fuel while ensuring stable fuel flow, thereby promoting the stable conveying of pulverized coal and SRF mixed fuel and avoiding the accumulation and blockage of pulverized coal and SRF mixed fuel.
[0050] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.
[0051] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A coupling system for flue gas driven SRF and coal-fired conveying boiler, characterized in that, The system includes a boiler, a flue gas driven conveying pipeline, a first branch, a second branch, a mixing chamber, and a screw conveyor. The boiler has a furnace and a flue. The flue outlet is connected to the flue gas inlet of the flue gas driven conveying pipeline via a fan. The flue gas outlet at the other end of the flue gas driven conveying pipeline is connected to the furnace. The side wall of the flue gas driven conveying pipeline has a first exhaust port, a second exhaust port, and a feed port sequentially arranged along the flue gas conveying direction. The first exhaust port is connected to the inlet end of the first branch, and the outlet end of the first branch is connected to the lower side of the mixing chamber via a blower. The second exhaust port is connected to the air inlet of the second branch, and the other end of the second branch is the feed inlet; SRF powder and coal powder are mixed in the mixing chamber, the discharge port of the mixing chamber is connected to the feed inlet of the screw conveyor, one end of the discharge port of the screw conveyor extends into the second branch, and the discharge port of the screw conveyor faces downwards corresponding to the feed inlet below, and an air inlet of the screw conveyor is also opened above the screw conveyor opposite to the discharge port of the screw conveyor; the flue gas passes sequentially through the air inlet of the screw conveyor, the discharge port of the screw conveyor, and the feed inlet in the second branch.
2. The coupling system for flue gas driven SRF and coal-fired conveying boiler according to claim 1, characterized in that, A flue gas denitrification device is also installed at the flue of the boiler, and the outlet of the flue gas denitrification device is connected to the fan through a corresponding flue gas pipeline.
3. A coupling system for flue gas driven SRF and coal-fired conveying boiler according to claim 1, characterized in that, It also includes a fuel transport device, a fuel crushing device, and a feeding hopper. The outlet of the fuel transport device is connected to the fuel crushing device, and the outlet of the fuel crushing device is connected to the feeding hopper. The lower outlet of the feeding hopper is connected to the mixing chamber inlet located above the mixing chamber. There are two sets of the fuel transport device, the fuel crushing device, and the feeding hopper. There are two mixing chamber inlets, namely an SRF powder inlet and a coal powder inlet. A drive shaft is installed inside the mixing chamber, and several stirring blades are installed on the drive shaft. The stirring blades are driven by the drive shaft to rotate and stir. The mixing chamber outlet is located at the bottom of the mixing chamber.
4. A coupling system for flue gas driven SRF and coal-fired conveying boiler according to claim 1, characterized in that, The blow pipe is inclined relative to the horizontal plane and the blowing direction is upward.
5. A coupling system for flue gas driven SRF and coal-fired conveying boiler according to claim 4, characterized in that, The angle between the blowpipe and the horizontal plane is 20° to 40°.
6. A coupling system for flue gas driven SRF and coal-fired conveying boiler according to claim 4 or 5, characterized in that, Several jet pipes are installed at equal intervals along the circumference of the lower outer wall of the mixing chamber, and all jet pipes are connected to the first branch.
7. A coupling system for flue gas driven SRF and coal-fired conveying boiler according to claim 1, characterized in that, The flue gas driven conveying pipe located between the second exhaust port and the feed port is designed as a pipe diameter changing section, in which the cross-sectional area of the pipe first decreases and then increases from the second exhaust port to the feed port.