Pre-drying high-moisture fuel boiler
By adding a pre-drying section in the boiler furnace and using high-temperature flue gas to pre-dry high-moisture fuel, the problem of incomplete combustion of high-moisture fuel in the boiler is solved, achieving efficient and stable combustion and improved safety performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- KAIFENG XINLI BOILER EQUIPMENT CO LTD
- Filing Date
- 2025-04-28
- Publication Date
- 2026-04-28
AI Technical Summary
In existing technologies, high-moisture fuels are difficult to burn completely in the boiler furnace, resulting in low combustion efficiency and high carbon content in the ash residue after combustion.
A pre-drying section is added to the boiler furnace. High-temperature flue gas from the boiler tail end is used to pre-dry the high-moisture fuel. The high-temperature flue gas is blown into the pre-drying section through the flue gas duct and the conical duct to dry the high-moisture fuel and reduce its humidity to ensure complete combustion in the main combustion section.
It achieves efficient and stable combustion of high-moisture fuels, improves combustion efficiency, reduces carbon content in ash, enhances fuel utilization, and improves boiler safety performance.
Smart Images
Figure CN224175153U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of boiler technology, specifically to a pre-dried high-moisture fuel boiler. Background Technology
[0002] A boiler is an energy conversion device that uses the heat energy released by the combustion of fuel or other heat energy to heat the working fluid, such as water, to certain parameters. Its main function is to convert the chemical energy in the fuel into heat energy. The boiler produces high-temperature flue gas by burning fuel, and the high-temperature flue gas transfers heat to the water through the boiler's heating surface, so that the water is heated into steam or hot water. It is widely used in power generation, heating, industrial production and other fields.
[0003] When high-moisture fuels, such as lignite, biomass, and sludge, are transported to boilers for combustion to release heat energy, they are difficult to burn completely in the boiler furnace due to their high moisture content. This results in low combustion efficiency and low ash content in the ash produced after combustion. Summary of the Invention
[0004] This invention addresses the problem of incomplete combustion and low combustion efficiency of high-moisture fuels in existing boiler furnaces by providing a pre-dried high-moisture fuel boiler. This boiler pre-dries the high-moisture fuel entering the boiler furnace by adding a pre-drying section, which enables the moisture in the high-moisture fuel to evaporate quickly, reducing the humidity of the high-moisture fuel, ensuring complete combustion of the high-moisture fuel in the boiler furnace, improving combustion efficiency, and reducing the carbon content of ash residue.
[0005] To achieve the above objectives, the technical solution of this utility model is: a pre-dried high-moisture fuel boiler, including an economizer and a boiler furnace. The boiler furnace includes a furnace body and an extended furnace, the extended furnace being disposed on one side of the furnace body and connected to the furnace body. A grate is disposed inside the boiler furnace. The inner cavity of the boiler furnace includes a pre-drying section, a main combustion section, and a burnout section arranged sequentially from left to right. By adding an extended furnace to one side of the furnace body to form a pre-drying section, high-moisture fuel can be dried in the pre-drying section, allowing the high-moisture fuel containing moisture to evaporate before being conveyed by the grate to the main combustion section for combustion.
[0006] The pre-drying section corresponds to the extended furnace. A gas supply assembly is located at the bottom of the boiler furnace corresponding to the pre-drying section. The gas supply assembly includes a flue gas hood and a flue gas duct. The flue gas hood corresponds to the pre-drying section. One end of the flue gas duct is located at the bottom of the flue gas hood and communicates with it, while the other end extends to and communicates with the economizer. A fan is installed on the flue gas duct. A feed hood is fixedly installed on the outside of the extended furnace, and an explosion-proof door is installed on the top of the extended furnace. The fan can transport the high-temperature flue gas discharged from the boiler tail to the flue gas hood via the flue gas duct, and blow it into the pre-drying section to dry the high-moisture fuel transported by the grate after passing through the pre-drying section, reducing the humidity of the high-moisture fuel so that it can be fully burned in the main combustion section. The feed hood can transport high-moisture fuel into the boiler furnace so that the high-moisture fuel transported by the grate passes sequentially through the pre-drying section, the main combustion section, and the burnout section.
[0007] Preferably, the bottom of the flue gas hood is provided with an air inlet hole, and a conical air duct is fixedly connected to the bottom of the flue gas hood at the position corresponding to the air inlet hole. The large end of the conical air duct faces upward and the small end faces downward. The high-temperature flue gas enters the flue gas hood through the conical air duct, which can make the high-temperature flue gas gradually diffuse and ensure that the high-temperature flue gas is evenly blown to the pre-drying section to dry the high-moisture fuel that has passed through the pre-drying section.
[0008] Preferably, the diameter of the flue gas duct is smaller than the diameter of the air inlet hole, and the two ends of the flue gas duct are respectively connected to the conical duct and the economizer. The fan draws high-temperature flue gas from the economizer at the tail of the boiler and delivers it to the flue gas hood through the flue gas duct and the conical duct in sequence.
[0009] Preferably, the feed hood is connected to the boiler furnace, and the grate feeding end extends through the pre-drying section to the bottom of the feed hood, ensuring that high-moisture fuel can fall onto the grate and that the high-moisture fuel transported by the grate passes through the pre-drying section.
[0010] Preferably, the top of the extended furnace is provided with an explosion-proof hole, and the explosion-proof door is installed at the explosion-proof hole. Since the moisture volatilized from the drying of high-moisture fuel is prone to accumulate, the addition of an explosion-proof door at the explosion-proof hole plays a role in preventing explosions and improving safety performance.
[0011] The beneficial effects of this utility model through the above technical solution are as follows:
[0012] This utility model has a reasonable structure and good performance. By adding a pre-drying section and extracting high-temperature flue gas from the tail of the boiler to pre-dry the high-moisture fuel, the moisture contained in the high-moisture fuel evaporates quickly, reducing the humidity of the high-moisture fuel. This ensures that the dried high-moisture fuel is fully burned and releases energy in the main combustion section, achieving efficient and stable combustion of high-moisture fuel, improving the utilization rate of high-moisture fuel, increasing combustion efficiency, and reducing the carbon content of combustion ash.
[0013] This invention achieves the purpose of conveying high-moisture fuel through the pre-drying section by adding an extended furnace chamber to the outside of the furnace body and extending the grate feeding end to below the feed hood. Meanwhile, the gas supply component fan conveys the high-temperature flue gas discharged from the tail of the boiler through the flue gas duct to the flue gas hood and blows it into the pre-drying section to dry the high-moisture fuel conveyed by the grate after passing through the pre-drying section, thereby achieving the effect of reducing the humidity of high-moisture fuel and achieving efficient and stable combustion of high-moisture fuel.
[0014] This invention utilizes a fan to draw high-temperature flue gas for drying high-moisture fuel. However, the moisture volatilized during the drying process of high-moisture fuel can easily accumulate and cause an explosion. Therefore, an explosion-proof door is installed at the explosion-proof hole to prevent explosions and improve the safety performance of the boiler. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of a pre-dried high-moisture fuel boiler according to this utility model;
[0016] Figure 2 yes Figure 1 Enlarged structural diagram at point A;
[0017] The attached diagram is labeled as follows: 1 is the furnace body, 2 is the extended furnace, 3 is the explosion-proof hole, 4 is the explosion-proof door, 5 is the grate, 6 is the pre-drying section, 7 is the main combustion section, 8 is the burnout section, 9 is the feed hood, 10 is the flue gas hood, 11 is the air inlet, 12 is the conical air duct, and 13 is the flue gas duct. Detailed Implementation
[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:
[0019] like Figures 1-2 As shown, a pre-dried high-moisture fuel boiler includes an economizer and a boiler furnace. The boiler furnace includes a furnace body 1 and an extended furnace 2. The extended furnace 2 is located on one side of the furnace body 1 and is connected to the furnace body 1. A grate 5 is installed inside the boiler furnace. The inner cavity of the boiler furnace includes a pre-drying section 6, a main combustion section 7, and a burnout section 8 arranged sequentially from left to right. The extended furnace 2 is installed on the left side of the furnace body 1 so that the inner cavity of the extended furnace 2 forms a pre-drying section 6 that is connected to the main combustion section 7. High-moisture fuel passes through the pre-drying section 6 for drying, so that the dried high-moisture fuel is fully burned and releases heat at the main combustion section 7. The grate 5 serves to transport the high-moisture fuel, which can be driven through the pre-drying section. The grate can be a chain grate, a reciprocating grate, or an inclined grate, selected according to the fuel characteristics. The high-moisture fuel includes lignite, biomass, and sludge, etc.
[0020] The pre-drying section 6 corresponds to the extended furnace 2. A gas supply assembly is provided at the bottom of the boiler furnace corresponding to the position of the pre-drying section 6. The gas supply assembly includes a flue gas hood 10 and a flue gas duct 13. The flue gas hood 10 corresponds to the pre-drying section 6. One end of the flue gas duct 13 is located at the bottom of the flue gas hood 10 and communicates with the flue gas hood 10. The other end extends to the economizer and communicates with the economizer. A fan is provided on the flue gas duct 13. A feed hood 9 is fixedly provided on the outside of the extended furnace 2. An explosion-proof door 4 is provided on the top of the extended furnace 2. The inner cavity of the extended furnace 2 is the pre-drying section. The economizer is connected to the furnace body 1 through the air duct. The high-temperature flue gas generated by the combustion of high-moisture fuel in the furnace is transported to the economizer through the air duct. Then, under the action of the fan, the high-temperature flue gas discharged from the economizer at the tail of the boiler is transported to the flue gas hood 10 through the flue gas duct 13 and blown into the pre-drying section 6 to directly heat the high-moisture fuel and dry it. The fan used is a high-temperature resistant fan from Zibo Borui Fan Co., Ltd. The temperature of the high-temperature flue gas is usually controlled between 200 and 400°C to prevent the high-moisture fuel from volatilizing or igniting too early in the pre-drying section 6.
[0021] The flue gas hood 10 has an air inlet 11 at its bottom. A conical air duct 12 is fixedly connected to the bottom of the flue gas hood 10 at the position corresponding to the air inlet 11. The larger end of the conical air duct 12 faces upward and the smaller end faces downward. The high-temperature flue gas transported by the flue gas duct 12 is transported to the flue gas hood 10 through the conical air duct 12 and the air inlet 11. The conical air duct 12 has a conical structure with a larger opening at the top and a smaller opening at the bottom, which allows the high-temperature flue gas to be gradually diffused in the conical air duct 12. The high-temperature flue gas is evenly blown to the pre-drying section 6, thereby pre-drying the high-moisture fuel that has passed through the pre-drying section 6 and drying the high-moisture fuel.
[0022] The diameter of the flue gas duct 13 is smaller than the diameter of the air inlet 11, and both ends of the flue gas duct 13 are connected to the conical duct 12 and the economizer, respectively. The high-temperature flue gas drawn by the fan from the economizer at the tail of the boiler is sequentially transported to the flue gas hood 10 through the flue gas duct 13 and the conical duct 12, so that the high-temperature flue gas is blown into the pre-drying section 6.
[0023] The feed hood 9 is connected to the boiler furnace. The feeding end of the grate 5 extends through the pre-drying section 6 to the bottom of the feed hood 9. This ensures that the high-moisture fuel entering the boiler furnace from the feed hood 9 can be transported by the grate 5, while also ensuring that the high-moisture fuel transported by the grate 5 passes through the pre-drying section 6, thus ensuring that the high-temperature flue gas dries the high-moisture fuel.
[0024] The extended furnace 2 is provided with an explosion-proof hole 3 at the top, and the explosion-proof door 4 is installed at the explosion-proof hole 3. When the high-temperature flue gas discharged from the economizer at the tail of the boiler is used to dry the high-moisture fuel, the high-moisture fuel has a high water content, and the volatilized water is easy to accumulate and cause an explosion. By installing an explosion-proof door 4 at the explosion-proof hole 3, the explosion-proof function can be effectively achieved.
[0025] The working principle of this utility model is as follows: When the boiler is in operation, the blower will transport the high-temperature flue gas discharged from the economizer at the tail of the boiler through the flue gas duct 13 and the conical duct 12 to the flue gas hood 10, and blow it into the pre-drying section 6; the high-moisture fuel will enter the boiler furnace through the feed hood 9 and fall onto the grate 5 and be transported by the grate 5. The grate 5 will carry the high-moisture fuel through the pre-drying section 6, the main combustion section 7 and the burnout section 8 in sequence. When the grate 5 carries the high-moisture fuel through the pre-drying section 6, the high-temperature flue gas dries the high-moisture fuel, and the moisture in the high-moisture fuel will evaporate rapidly, reducing the humidity of the high-moisture fuel. Then it will be transported by the grate 5 to the main combustion section 7. The dried high-moisture fuel will be fully burned in the main combustion section 7 to release energy, and then completely burned in the burnout section 8 to reduce the carbon content of the ash and slag, thereby achieving efficient and stable combustion of the high-moisture fuel.
[0026] The embodiments described above are merely preferred embodiments of the utility model and are not intended to limit the scope of the utility model. Therefore, all equivalent changes or modifications made to the technical solutions described in the scope of the utility model patent application should be included within the scope of the utility model patent application.
Claims
1. A pre-dried high-moisture fuel boiler, comprising an economizer, characterized in that, It also includes a boiler furnace, which includes a furnace body (1) and an extended furnace (2). The extended furnace (2) is located on one side of the furnace body (1) and is connected to the furnace body (1). A grate (5) is provided inside the boiler furnace. The inner cavity of the boiler furnace includes a pre-drying section (6), a main combustion section (7) and a burnout section (8) arranged from left to right. The pre-drying section (6) corresponds to the extended furnace (2). A gas supply component is provided at the bottom of the boiler furnace corresponding to the position of the pre-drying section (6). The gas supply component includes a flue gas hood (10) and a flue gas duct (13). The flue gas hood (10) corresponds to the pre-drying section (6). One end of the flue gas duct (13) is located at the bottom of the flue gas hood (10) and is connected to the flue gas hood (10). The other end extends to the economizer and is connected to the economizer. A fan is provided on the flue gas duct (13). A feed hood (9) is fixedly provided on the outside of the extended furnace (2). An explosion-proof door (4) is provided on the top of the extended furnace (2).
2. A pre-dried high-moisture fuel boiler according to claim 1, characterized in that, The bottom of the smoke hood (10) is provided with an air inlet (11), and a conical air duct (12) is fixedly connected to the bottom of the smoke hood (10) at the position corresponding to the air inlet (11). The large end of the conical air duct (12) faces upward and the small end faces downward.
3. A pre-dried high-moisture fuel boiler according to claim 2, characterized in that, The diameter of the flue gas duct (13) is smaller than the diameter of the air inlet (11), and the two ends of the flue gas duct (13) are connected to the conical duct (12) and the economizer, respectively.
4. A pre-dried high-moisture fuel boiler according to claim 1, characterized in that, The feed hood (9) is connected to the boiler furnace, and the feeding end of the grate (5) extends through the pre-drying section (6) to the bottom of the feed hood (9).
5. A pre-dried high-moisture fuel boiler according to claim 1, characterized in that, The extended furnace chamber (2) has an explosion-proof hole (3) at the top, and the explosion-proof door (4) is located at the explosion-proof hole (3).