Smoke exhaust temperature accurate control type boiler air and smoke structure
By adding bypass ignition air to the boiler smoke structure and optimizing the air preload structure, the problem of low smoke exhaust temperature at low load is solved, precise control of smoke exhaust temperature and extension of the boiler operation cycle are achieved, achieving The purpose of energy conservation and emission reduction.
Patent Information
- Application Number
- CN202420578057.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-25
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2034-03-25
AI Technical Summary
When the boiler is low in winter, the smoke exhaust temperature may be lower than 100℃, causing the tail dust collector to bond and negative pressure to rise, affecting the boiler operation cycle.
Design a boiler smoke structure with precise control of smoke exhaust temperature. By adding bypass feeding ignition air at the outlet of the air preloader, adjusting the valve opening of the air preloader and ignition air, optimizing the composition structure of the air preloader and reduce entry The pipeline resistance of the ignition air controls the ratio of hot and cold air to ensure accurate control of smoke exhaust temperature.
It increases the smoke exhaust temperature under low load, extends the operating cycle of the dust collector, reduces energy consumption, and achieves the energy-saving and emission reduction effect of the boiler.
Smart Images
Figure CN222230584U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of boilers, in particular to a boiler air and smoke structure with precise control of exhaust smoke temperature. Background Art
[0002] In order to reduce the energy consumption and operating costs of coal-using enterprises, many coal-using enterprises choose to upgrade their boilers. By upgrading the boiler from sub-high temperature and sub-high pressure to high temperature and high pressure or higher-level parameter boilers, the power generation efficiency can be significantly improved. In addition, controlling the maximum heat loss exhaust temperature of the boiler is also a key measure for energy saving and consumption reduction. The exhaust temperature has a great impact on the thermal efficiency of the boiler. Every increase of 15°C in the exhaust temperature will cause the thermal efficiency of the boiler to decrease by 1%. Therefore, controlling the boiler exhaust temperature at a lower level can ensure that the boiler achieves the maximum thermal efficiency.
[0003] In response to the peak load demand, some special measures were taken during the boiler design to increase the load span. In order to better cope with the load difference between day and night, a superheater was added to increase the main steam temperature, and an ash cooler was added to control the furnace temperature. These design improvements have significantly enhanced the peak load capacity of the boiler. In order to further reduce energy consumption, an efficient economizer layout was also adopted during the design. However, this design may cause the exhaust gas temperature to be lower than 100°C at low load in winter, resulting in adhesion on the bag of the tail dust collector, which in turn causes the negative pressure of the tail dust collector to increase, affecting the operation cycle of the boiler. Utility Model Content
[0004] In order to solve the above technical problems, the present application provides a boiler air and smoke structure with precise control of exhaust gas temperature.
[0005] The present application provides a boiler air and smoke structure with precise exhaust temperature control, which adopts the following technical solutions:
[0006] A boiler air and smoke structure with precise exhaust temperature control, characterized by comprising:
[0007] An air duct, wherein the air duct is formed as a tubular member with two ends open so that hot flue gas is input from the upper end of the air duct and transmitted toward the lower end of the air duct;
[0008] An air preheater, the air preheater is arranged along the length direction of the air duct and at least a part of the air preheater is arranged in the air duct;
[0009] An ignition tube, the ignition tube is arranged at one side of the air duct and is connected to the air outlet of the air preheater;
[0010] A bypass air supply pipe is arranged on a side of the air duct close to the ignition tube and one end of the bypass air supply pipe is connected to the air preheater, and the other end of the bypass air supply pipe is connected to the ignition tube.
[0011] An ignition combustion chamber is arranged at one end of the ignition tube and is communicated with the ignition tube.
[0012] Through the above technical scheme, the present application adds a bypass at the outlet of the air preheater to deliver ignition air. By opening the bypass ignition air valve when the boiler is under low load, closing the ignition air regulating valve and the mixing air regulating valve after the air preheater, and reducing the size of the main air gate entering the wind chamber, a part of the air entering the wind chamber is forced to pass through the ignition air. With the cooperation of the main air gate and the ignition air, the required fluidizing air volume is delivered to the water-cooled air chamber, thereby increasing the exhaust gas temperature under low load.
[0013] Furthermore, the air preheater includes a first air preheating duct and a second air preheating duct which are spaced apart from each other, the first air preheating duct is provided with a first hot air outlet and a first cold air inlet, and the second air preheating duct is provided with a second hot air outlet and a second cold air inlet.
[0014] Furthermore, the first hot air outlet is communicated with the ignition tube.
[0015] Furthermore, the air preheater is provided with three passes.
[0016] Furthermore, one end of the bypass air supply pipe is connected to a return path of the air preheater.
[0017] Through the above technical scheme, the present application optimizes the component structure within the air preheater. Since part of the air entering the ignition tube does not completely pass through the primary air preheater, the amount of cold air entering the primary air preheater is reduced. Since the amount of primary cold air entering the second and third passes is reduced, the heat exchange rate between the flue gas and the primary air-cooled air preheater will also be reduced accordingly. In this way, the exhaust temperature under low load is increased.
[0018] Furthermore, the cross-sectional area of the bypass air supply pipe is 1 / 3-2 / 3 of the cross-sectional area of the air duct.
[0019] Furthermore, the bypass air supply pipe is provided with a first valve to control the amount of cold air introduced into the ignition tube through the bypass air supply pipe.
[0020] Furthermore, the first hot air outlet is provided with a second valve to control the air volume of the hot air introduced into the ignition tube through the first hot air outlet.
[0021] Through the above technical solution, in order to reduce the pipe resistance of the ignition air, the cross-sectional area of the bypass ignition air is adjusted. Under the coordination of the main air door and the bypass ignition air, the opening of the two valves is adjusted to control the ratio of hot air and cold air entering the water-cooled air chamber. Since the main air door and the bypass ignition air both use regulating valves, the exhaust temperature can be accurately controlled after adjustment. While ensuring the safe operation of the dust collector, the low-load adjustment range can be increased, which will generate benefits for energy conservation and emission reduction for enterprises.
[0022] In summary, the present application includes at least one of the following beneficial technical effects:
[0023] 1. The present application adds a bypass at the outlet of the air preheater to deliver ignition air. When the boiler is under low load, an ignition air valve of the bypass is opened, the ignition air regulating valve and the mixing air regulating valve after the air preheater are closed, and the size of the main air door entering the wind chamber is reduced, so that a part of the air entering the wind chamber is forced to pass through the ignition air. With the cooperation of the main air door and the ignition air, the required fluidizing air volume is delivered to the water-cooled air chamber, thereby increasing the exhaust gas temperature under low load.
[0024] 2. The present application optimizes the composition structure within the air preheater. Since part of the air entering the ignition tube does not completely pass through the primary air preheater, the amount of cold air entering the primary air preheater is reduced. Since the amount of primary cold air entering the second and third passes is reduced, the heat exchange rate between the flue gas and the primary air-cooled air preheater will also be reduced accordingly. In this way, the exhaust temperature under low load is increased.
[0025] 3. In order to reduce the pipe resistance of the ignition air, the cross-sectional area of the bypass ignition air is adjusted. Under the coordination of the main air door and the bypass ignition air, the opening of the two valves is adjusted to control the ratio of hot air and cold air entering the water-cooled air chamber. Since the main air door and the bypass ignition air both use regulating valves, the exhaust temperature can be accurately controlled after adjustment. While ensuring the safe operation of the dust collector, the low-load adjustment range can be increased, which will generate benefits for energy conservation and emission reduction for enterprises. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is a structural schematic diagram of a boiler air and smoke structure with precise exhaust temperature control according to Example 1 of the present application.
[0027] Explanation of the accompanying drawings: 1. air duct; 2. air preheater; 3. ignition tube; 4. bypass air supply pipe; 41. second valve; 5. ignition combustion chamber; 21. first air preheater duct; 22. second air preheater duct; 211. first cold air inlet; 212. first hot air outlet; 213. first valve; 221. second cold air inlet; 222. second hot air outlet. DETAILED DESCRIPTION
[0028] The following is combined with Figure 1 This application is described in further detail.
[0029] Embodiment 1 of the present application discloses a boiler air and smoke structure with precise control of exhaust gas temperature.
[0030] The air and smoke structure of the boiler with precise control of exhaust temperature includes an air duct, which is a cylindrical pipe with openings at both ends. At the lower end of the air duct, there is a smoke exhaust port arranged vertically to the air duct. The hot smoke enters from the upper end of the air duct and is discharged through the smoke exhaust port connected to the lower end of the air duct.
[0031] In the air duct, there is an air preheater arranged along the length direction of the air duct, and the air preheater is provided with two first air preheater pipes and second air preheater pipes arranged at intervals, and the first air preheater pipe and the second air preheater pipe are bent along the length direction thereof and a part of each of them is arranged in the air duct along the radial direction of the air duct. The first air preheater pipe is provided with a first cold air inlet and a first hot air outlet, and the second air preheater pipe is provided with a second cold air inlet and a second hot air outlet, wherein the first cold air inlet is arranged at the lower end of the second cold air inlet, and the first cold air inlet and the second cold air inlet are both arranged at one side of the lower end of the air duct, and the first hot air outlet and the second hot air outlet are both arranged at the other side of the upper end of the air duct, and the first hot air outlet is arranged at the lower end of the second hot air outlet.
[0032] The first air pre-duct and the second air pre-duct arranged in the air duct are both provided with three returns. A bypass air supply pipe is provided at one return of the first air pre-duct. The bypass air supply pipe is arranged on a side of the air duct close to the ignition tube, and one end of the bypass air supply pipe is connected to the air preheater, and the other end of the bypass air supply pipe is connected to the ignition tube.
[0033] It should be noted that the cross-sectional area of the bypass air supply pipe is 1 / 3-2 / 3 of the cross-sectional area of the air duct. A first valve is also provided on the bypass air supply pipe to control the amount of cold air introduced into the ignition tube by the bypass air supply pipe, and a second valve is provided at the first cold air outlet to control the amount of hot air introduced into the ignition tube by the first hot air outlet.
[0034] The first hot air outlet is connected to one end of the ignition tube, and the other end of the ignition tube is connected to the ignition combustion chamber. The ignition tube is a columnar structure with openings at both ends. The ignition combustion chamber is vertically connected to the ignition tube and forms a funnel-shaped chamber.
[0035] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A boiler air and smoke structure with precise exhaust temperature control, characterized in that: include: An air duct, wherein the air duct is formed as a tubular member with two ends open so that hot flue gas is input from the upper end of the air duct and transmitted toward the lower end of the air duct; An air preheater, the air preheater is arranged along the length direction of the air duct and at least a part of the air preheater is arranged in the air duct; An ignition tube, the ignition tube is arranged at one side of the air duct and is connected to the air outlet of the air preheater; A bypass air supply pipe, wherein the bypass air supply pipe is arranged on one side of the air duct close to the ignition tube and one end of the bypass air supply pipe is connected to the air preheater, and the other end of the bypass air supply pipe is connected to the ignition tube; An ignition combustion chamber is arranged at one end of the ignition tube and is communicated with the ignition tube.
2. According to claim 1, a boiler air and smoke structure with precise exhaust temperature control is characterized in that: The air preheater comprises a first air preheating duct and a second air preheating duct which are spaced apart from each other. The first air preheating duct is provided with a first hot air outlet and a first cold air inlet, and the second air preheating duct is provided with a second hot air outlet and a second cold air inlet.
3. The exhaust gas temperature precise control boiler air and smoke structure according to claim 2 is characterized in that: The first hot air outlet is communicated with the ignition tube.
4. The exhaust gas temperature precise control boiler air and smoke structure according to claim 2 is characterized in that: The air preheater is provided with three passes.
5. The exhaust gas temperature precise control boiler air and smoke structure according to claim 4 is characterized in that: One end of the bypass air supply pipe is connected to a return path of the air preheater.
6. The exhaust gas temperature precise control boiler air and smoke structure according to claim 5 is characterized in that: The cross-sectional area of the bypass air supply pipe is 1 / 3-2 / 3 of the cross-sectional area of the air duct.
7. The exhaust gas temperature precise control boiler air and smoke structure according to claim 5 is characterized in that: The bypass air supply pipe is provided with a first valve to control the air volume of the cold air introduced into the ignition tube through the bypass air supply pipe.
8. The exhaust gas temperature precise control boiler air and smoke structure according to claim 5 is characterized in that: The first hot air outlet is provided with a second valve to control the air volume of the hot air entering the ignition tube from the first hot air outlet.