Biomass combustion structure

Abstract

The present application provides a kind of biomass combustion structure, including combustion furnace and air supply combustion-supporting mechanism, hearth is provided with grate in combustion furnace, combustion furnace has feed hole, the communicating hole matched with air supply combustion-supporting mechanism, grate includes primary combustion zone, secondary combustion zone and sediment zone from the center of grate to outside in turn, feed hole is located above grate, communicating hole is located below grate;Air supply combustion-supporting mechanism includes air blower, connecting air pipe and controllable bellows, controllable bellows is located below grate, controllable bellows is provided with air inlet hole that communicates with air outlet end, controllable bellows is also provided with first air supply hole towards primary combustion zone and second air supply hole towards secondary combustion zone, the aperture of first air supply hole is larger than the aperture of second air supply hole.The present application can solve the problem that biomass fuel is not fully combusted in prior art, combustion-supporting air is too large to blow fuel and block heat dissipation pipe, biomass fuel is easy to coke on grate and affect combustion effect.

Description

Technical Field

[0001] This invention relates to the field of combustion equipment technology, and in particular to a biomass combustion structure. Background Technology

[0002] Biomass fuel refers to fuel made by burning biomass materials, primarily agricultural and forestry waste such as straw, sawdust, bagasse, and rice husks, which is distinct from fossil fuels. The main application of biomass fuel is in biomass pellet fuel, which uses agricultural and forestry waste as raw material and processes it through crushing, mixing, extrusion, and drying to produce various shaped pellets that can be directly burned—a clean fuel.

[0003] Existing biomass combustion furnaces generally place biomass fuel on the grate of the furnace for overall combustion. This combustion method is a crude combustion method. Under this method, if the blower air volume is simply increased, there will be a problem that the air is too strong and blows the fuel up and blocks the heat dissipation pipes of the furnace. If the air volume is normal, there will be a problem of incomplete combustion of fuel, which will cause the biomass fuel to coke on the grate and affect the combustion effect.

[0004] Therefore, it is necessary to propose a biomass combustion structure to solve or at least alleviate the above-mentioned defects. Summary of the Invention

[0005] The main objective of this invention is to provide a biomass combustion structure to solve the technical problem that existing biomass combustion furnaces generally concentrate biomass fuel on the grate of the furnace for overall combustion. This combustion method results in incomplete fuel combustion, which causes biomass fuel to easily coke on the grate and affect the combustion effect.

[0006] To achieve the above objectives, the present invention provides a biomass combustion structure, including a combustion furnace and an air supply and combustion-aiding mechanism, wherein a grate is provided inside the furnace chamber of the combustion furnace, wherein...

[0007] The combustion furnace has a feed hole and a connecting hole that matches the air supply and combustion assist mechanism. The grate includes a main combustion zone, a secondary combustion zone, and a slag zone arranged sequentially from the center of the grate outwards. The feed hole is located above the grate, and the connecting hole is located below the grate.

[0008] The air supply and combustion-aiding mechanism includes a blower, connecting air ducts, and a controllable air box; wherein...

[0009] The blower is located outside the combustion furnace; the connecting air duct includes an air inlet end and an air outlet end arranged opposite to each other, the air inlet end is connected to the air outlet of the blower, and the air outlet end enters the furnace through the connecting hole and is connected to the controllable air box.

[0010] The controllable air box is located below the grate. The controllable air box has an air inlet that connects to the air outlet. The controllable air box also has a first air supply hole facing the main combustion zone and a second air supply hole facing the secondary combustion zone. The diameter of the first air supply hole is larger than the diameter of the second air supply hole.

[0011] Preferably, the controllable air box includes a lower air inlet end and an upper air outlet end. The lower air inlet end is provided with the air inlet hole, and the upper air outlet end is in the shape of a frustum with a smaller top and a larger bottom. The top surface of the upper air outlet end is provided with the first air supply hole, and the side surface of the upper air outlet end is provided with the second air supply hole.

[0012] Preferably, the main combustion zone is circular, the secondary combustion zone and the sludge zone are both annular, and the main combustion zone, the secondary combustion zone and the sludge zone are concentrically arranged.

[0013] Preferably, it further includes a feeding mechanism, which includes a drive motor, a material conveying and guiding mechanism, a first feeding mechanism and a second feeding mechanism that are drively connected to the drive motor, wherein...

[0014] The output shaft of the drive motor is provided with a first sprocket;

[0015] The first feeding mechanism includes a cylindrical first housing and a first helical blade shaft rotatably disposed within the first housing; the first helical blade shaft includes a first driving end and a first discharging end disposed opposite to each other, the first driving end of the first helical blade shaft extends out of the first housing, and a second sprocket is fixed on the first driving end; the top of the first housing has a first feeding opening on the side near the first driving end, and the bottom of the first housing has a first discharging opening on the side near the first discharging end;

[0016] The second feeding mechanism is located below the first feeding mechanism. The second feeding mechanism includes a cylindrical second outer shell and a second helical blade shaft rotatably disposed within the second outer shell. The second helical blade shaft includes a second driving end and a second discharge end disposed opposite to each other. The second driving end of the second helical blade shaft extends out of the second outer shell, and a third sprocket is fixed on the second driving end. A second feeding opening is formed on the top of the second outer shell near the second driving end. A second discharge opening communicating with the feeding hole is opened near the second discharge end of the second outer shell. The second feeding opening and the first discharge opening are connected by a feeding channel.

[0017] The material conveying and guiding mechanism has an inlet guide port that communicates with the second outlet opening and an outlet guide port that communicates with the inlet hole, so as to guide the biomass fuel from the inlet guide port to the outlet guide port and fall onto the main combustion zone.

[0018] Preferably, the diameter of the first air supply hole is set between 3mm and 25mm.

[0019] Preferably, the diameter of the second air supply hole is set between 2mm and 20mm.

[0020] Preferably, there are multiple first air supply holes, which are evenly distributed on the top surface of the upper air outlet end, and the extension direction of each first air supply hole is perpendicular to the top surface of the upper air outlet end. There are also multiple second air supply holes, which are evenly distributed on the side surface of the upper air outlet end, and the extension direction of each second air supply hole is perpendicular to the side surface of the upper air outlet end.

[0021] Preferably, the slope angle of the side of the upper air supply end is set between 0° and 45°.

[0022] Preferably, the diameter of the second air supply hole gradually decreases from top to bottom.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention provides a biomass combustion structure, including a combustion furnace and an air supply and combustion-aiding mechanism. The combustion furnace has a grate inside its furnace chamber, a feed hole, and a connecting hole matching the air supply and combustion-aiding mechanism. The grate includes a main combustion zone, a secondary combustion zone, and a slag zone arranged sequentially from the center outwards. The feed hole is located above the grate, and the connecting hole is located below the grate. The air supply and combustion-aiding mechanism includes a blower, a connecting air duct, and a controllable air box located below the grate. The controllable air box has an air inlet connecting to the air outlet, a first air supply hole facing the main combustion zone, and a second air supply hole facing the secondary combustion zone. The diameter of the first air supply hole is larger than the diameter of the second air supply hole. This application can solve the problems of incomplete combustion of biomass fuel and the tendency of biomass fuel to coke on the grate, affecting combustion efficiency, in the prior art.

[0025] Specifically, biomass pellets enter the furnace through the feed hole and fall onto the grate for combustion. Air from the blower enters the controllable air box through the connecting duct. In the controllable air box, air is blown to the main combustion zone through the first air inlet. The diameter of the first air inlet can be set to supply a large volume of air to the main combustion zone, ensuring complete combustion of the thick middle layer of biomass. The diameter of the second air inlet can be set to 2mm-20mm. Some biomass fuel is in a semi-combustible state under the blowing of the first air inlet. The semi-combustible biomass pellets jump to the secondary combustion zone. Due to the smaller diameter of the second air inlet, an appropriate amount of air is blown into the secondary combustion zone, ensuring complete combustion of the semi-combustible pellets without blowing them too high. This solves the problems of incomplete combustion of biomass fuel and the problem that the secondary combustion zone of the existing grate is prone to clogging the heat dissipation pipes in the furnace due to excessive ash. At the same time, the presence of the second air inlet can effectively blow the ash and slag of the biomass fuel to the slag settling zone. The ash and slag fall to the bottom of the furnace, solving the problem of coking on the grate due to excessive ash and slag in the existing technology. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0027] Figure 1 This is a cross-sectional schematic diagram of the overall structure in one embodiment of the present invention;

[0028] Figure 2 This is a top view of the overall structure in one embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the combined structure of the connecting duct and the controllable air box in one embodiment of the present invention;

[0030] Figure 4 for Figure 1 Enlarged diagram of point A in the diagram;

[0031] Figure 5 This is a cross-sectional schematic diagram of the feeding mechanism in one embodiment of the present invention.

[0032] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0033] Explanation of icon numbers:

[0034] 10. Furnace; 110. Grate; 111. Main combustion zone; 112. Secondary combustion zone; 113. Slag zone; 20. Air supply and combustion aid mechanism; 210. Blower; 220. Connecting air duct; 221. Air inlet; 222. Air outlet; 230. Controllable air box; 231. Lower air inlet; 232. Upper air outlet; 233. First air supply hole; 234. Second air supply hole; 30. Feeding mechanism; 3 20. Material conveying and guiding mechanism; 321. Feed inlet guide port; 322. Discharge guide port; 330. First feeding mechanism; 331. First outer shell; 332. First helical blade shaft; 333. First feed opening; 334. Second sprocket; 340. Second feeding mechanism; 341. Second outer shell; 342. Second helical blade shaft; 343. Third sprocket; 350. Feeding channel; 40. Biomass fuel. Detailed Implementation

[0035] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0038] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0039] Please see Figures 1 to 5 An embodiment of the present invention provides a biomass combustion structure, including a combustion furnace (not shown) and an air supply and combustion aid mechanism 20. A grate 110 is provided inside the furnace chamber 10 of the combustion furnace.

[0040] The combustion furnace has a feed hole (not shown in the figure) and a connecting hole (not shown in the figure) that matches the air supply and combustion mechanism 20. The grate 110 includes a main combustion zone 111, a secondary combustion zone 112 and a slag zone 113 arranged sequentially from the center of the grate 110. The feed hole is located above the grate 110 and the connecting hole is located below the grate 110.

[0041] The air supply and combustion assist mechanism 20 includes a blower 210, a connecting air duct 220, and a controllable air box 230; wherein, the blower 210 is located outside the combustion furnace; the connecting air duct 220 includes an air inlet end 221 and an air outlet end 222 arranged opposite to each other, the air inlet end 221 is connected to the air outlet of the blower 210, and the air outlet end 222 enters the furnace chamber 10 through the connecting hole and is connected to the controllable air box 230;

[0042] The controllable air box 230 is located below the grate 110. The controllable air box 230 has an air inlet (not shown) connecting to the air outlet 222. The controllable air box 230 also has a first air supply hole 233 facing the main combustion zone 111 and a second air supply hole 234 facing the secondary combustion zone 112. The diameter of the first air supply hole 233 is larger than the diameter of the second air supply hole 234. As a preferred example, the diameter of the first air supply hole 233 is set between 3mm and 25mm. As a preferred example, the diameter of the second air supply hole 234 is set between 2mm and 20mm. When determining the specific values, it is ensured that the diameter of the first air supply hole 233 is larger than the diameter of the second air supply hole 234.

[0043] Further, see appendix. Figure 2 The main combustion zone 111 is circular, the secondary combustion zone 112 and the sludge zone 113 are both annular, and the main combustion zone 111, the secondary combustion zone 112 and the sludge zone 113 are concentrically arranged.

[0044] Workflow: Biomass pellets enter the furnace 10 through the feed hole and fall onto the grate 110 for combustion (ignition mechanism not shown). Air from the blower 210 enters the controllable air box 230 through the connecting air duct 220. From the controllable air box 230, air is blown into the main combustion zone 111 through the first air supply hole 233. The diameter of the first air supply hole 233 can be set to a large air volume of 20mm to supply the main combustion zone 111, ensuring complete combustion of the thick intermediate material layer. The diameter of the second air supply hole 234 can be set to 2mm-20mm. Part of the biomass fuel 40 is in a semi-combustion state under the blowing of the first air supply hole 233. The biomass pellets in the combustion state jump to the secondary combustion zone 112. Due to the small diameter of the second air inlet 234, an appropriate amount of air is blown into the secondary combustion zone 112, so that the semi-burned pellets are fully burned and not blown too high. This solves the problem of incomplete combustion of biomass fuel 40 and the problem of blockage of heat dissipation pipes in the furnace 10 caused by too much ash in the secondary combustion zone 112 of the existing grate 110. At the same time, due to the presence of the second air inlet 234, the ash and slag of biomass fuel 40 can be effectively blown to the slag settling zone 113. The ash and slag fall into the bottom of the furnace 10, solving the problem of coking on the grate 110 due to excessive ash and slag in the existing technology.

[0045] In a preferred embodiment, the controllable air box 230 includes a lower air inlet end 231 and an upper air outlet end 232. The lower air inlet end 231 has an air inlet hole, and the upper air outlet end 232 is a frustum shape, smaller at the top and larger at the bottom. The top surface of the upper air outlet end 232 has a first air supply hole 233, and the side surface of the upper air outlet end 232 has a second air supply hole 234. As a preferred example, the slope angle of the side surface of the upper air supply end is set between 0° and 45°, where the slope foot is the inclination angle of the frustum (the angle corresponding to the slope). It should be noted that the slope angle of the side surface of the upper air outlet end 232 should ensure that the second air supply hole 234 can cover the secondary combustion zone 112, so that the biomass combustion in the secondary combustion zone 112 is complete, avoiding the problem of incomplete combustion of biomass fuel 40.

[0046] In a preferred embodiment, the diameter of the second air inlet 234 gradually decreases from top to bottom. It is worth noting that the biomass fuel 40 is mainly concentrated in the main combustion zone 111, and the amount of biomass fuel 40 accumulated from the main combustion zone 111 outwards gradually decreases. Under the same airflow force, areas with less material are more easily blown up. Therefore, to ensure uniform combustion, in this embodiment, the diameter of the second air inlet 234 gradually decreases from top to bottom. This ensures that the biomass fuel 40 in the secondary combustion zone 112 can be fully burned without being blown too high, thus ensuring uniform combustion. Simultaneously, the full combustion of the biomass fuel 40 in the secondary combustion zone 112 solves the problem of coking on the grate 110 due to excessive ash content.

[0047] Furthermore, there are multiple first air supply holes 233, which are evenly arranged on the top surface of the upper air outlet end 232. The extension direction of each first air supply hole 233 is perpendicular to the top surface of the upper air outlet end 232. Similarly, there are multiple second air supply holes 234, which are evenly arranged on the side surface of the upper air outlet end 232. The extension direction of each second air supply hole 234 is perpendicular to the side surface of the upper air outlet end 232. Specifically, the number of first air supply holes 233 and second air supply holes 234 can be set by those skilled in the art as needed.

[0048] In a preferred embodiment, the system also includes a feeding mechanism 30, which includes a drive motor (not shown), a material conveying and guiding mechanism 320, a first feeding mechanism 330 and a second feeding mechanism 340 that are connected to the drive motor in a transmission manner, wherein a first sprocket (not shown) is provided on the output shaft of the drive motor.

[0049] The first feeding mechanism 330 includes a cylindrical first housing 331 and a first helical blade shaft 332 rotatably disposed within the first housing 331. The first helical blade shaft 332 includes a first driving end (not shown) and a first discharging end (not shown) disposed opposite to each other. The first driving end of the first helical blade shaft 332 extends out of the first housing 331, and a second sprocket 334 is fixed on the first driving end. The top of the first housing 331 has a first feeding opening 333 on the side near the first driving end, and the bottom of the first housing 331 has a first discharging opening (not shown) on the side near the first discharging end.

[0050] The second feeding mechanism 340 is disposed below the first feeding mechanism 330. The second feeding mechanism 340 includes a cylindrical second housing 341 and a second helical blade shaft 342 rotatably disposed within the second housing 341. The second helical blade shaft 342 includes a second driving end (not shown) and a second discharge end (not shown) disposed opposite to each other. The second driving end of the second helical blade shaft 342 extends out of the second housing 341, and a third sprocket 343 is fixed on the second driving end. A second feeding opening (not shown) is formed on the top of the second housing 341 on the side near the second driving end. A second discharge opening communicating with the feeding hole is opened near the second discharge end of the second housing 341. The second feeding opening and the first discharge opening are connected through a feeding channel 350.

[0051] The material conveying and guiding mechanism 320 has a feed guide port 321 that communicates with the second discharge opening and a discharge guide port 322 that communicates with the feed hole, so as to guide the biomass fuel 40 from the feed guide port 321 to the discharge guide port 322 and fall onto the main combustion zone 111.

[0052] Working process: Biomass fuel 40 enters the first outer shell 331 through the first feed opening 333. The drive motor drives the first sprocket to rotate, which in turn drives the second sprocket 334, thereby rotating the first helical blade shaft 332. This transfers the biomass fuel 40 from the first feed opening 333 to the first discharge opening, and then through the feeding channel 350 into the second outer shell 341 via the second feed opening. The drive motor can be configured to synchronously drive the third sprocket 343 to rotate, which in turn drives the second helical blade shaft 342 to rotate. This transfers the biomass fuel 40 from the second feed opening to the second discharge opening, and then through the feeding guide mechanism 320 into the furnace 10 for combustion. The use of a double auger transmission system results in high transmission efficiency and a compact structure.

[0053] Furthermore, the material guiding path of the material conveying and guiding mechanism 320 corresponds to the main combustion zone 111, that is, the biomass fuel 40 passing through the material conveying and guiding mechanism 320 falls preferentially into the main combustion zone 111 for combustion, thereby improving the overall combustion efficiency.

[0054] Furthermore, the material conveying guide mechanism 320 and the second housing 341 can be connected by a flange or by integral molding. In a specific embodiment, they are connected by a flange for easy disassembly.

[0055] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A biomass combustion structure, characterized in that, The system includes a combustion furnace and an air-supplying combustion-aiding mechanism. The combustion furnace has a grate inside its furnace chamber. The combustion furnace has a feed port and a connecting hole matching the air-supplying combustion-aiding mechanism. The grate includes a main combustion zone, a secondary combustion zone, and a slag zone arranged sequentially from the center outwards. The feed port is located above the grate, and the connecting hole is located below the grate. The air-supplying combustion-aiding mechanism includes a blower, connecting air ducts, and a controllable air box. The blower is located outside the combustion furnace. The connecting duct includes an air inlet and an air outlet arranged opposite to each other. The air inlet is connected to the air outlet of the blower, and the air outlet enters the furnace through the connecting hole and is connected to the controllable air box. The controllable air box is located below the grate. The controllable air box has an air inlet that connects to the air outlet. The controllable air box also has a first air supply hole facing the main combustion zone and a second air supply hole facing the secondary combustion zone. The diameter of the first air supply hole is larger than the diameter of the second air supply hole. The controllable air box includes a lower air inlet and an upper air outlet. The lower air inlet has an air inlet hole, and the upper air outlet is a frustum-shaped structure with a smaller top and a larger bottom. The top surface of the upper air outlet has a first air supply hole, and the side surface of the upper air outlet has a second air supply hole. The main combustion zone is circular, and the secondary combustion zone and the sludge zone are both annular. The main combustion zone, the secondary combustion zone, and the sludge zone are concentrically arranged. The diameter of the second air supply hole gradually decreases from top to bottom.

2. The biomass combustion structure according to claim 1, characterized in that, It also includes a feeding mechanism, which comprises a drive motor, a material conveying and guiding mechanism, a first feeding mechanism and a second feeding mechanism connected to the drive motor, wherein a first sprocket is provided on the output shaft of the drive motor; the first feeding mechanism includes a cylindrical first housing and a first helical blade shaft rotatably disposed within the first housing; the first helical blade shaft includes a first driving end and a first discharging end disposed opposite to each other, the first driving end of the first helical blade shaft extends out of the first housing, and a second sprocket is fixed on the first driving end; a first feeding opening is formed on the top of the first housing near the first driving end, and a first discharging opening is formed on the bottom of the first housing near the first discharging end; the second feeding mechanism is disposed below the first feeding mechanism, the second... The feeding mechanism includes a cylindrical second housing and a second helical blade shaft rotatably disposed within the second housing. The second helical blade shaft includes a second drive end and a second discharge end disposed opposite to each other. The second drive end of the second helical blade shaft extends out of the second housing, and a third sprocket is fixed on the second drive end. A second feed opening is formed on the top of the second housing near the second drive end. A second discharge opening communicating with the feed opening is provided near the second discharge end of the second housing. The second feed opening and the first discharge opening are connected by a feeding channel. The material guiding mechanism has a feed guide port communicating with the second discharge opening and a discharge guide port communicating with the feed opening, so as to guide biomass fuel from the feed guide port to the discharge guide port and fall onto the main combustion zone.

3. The biomass combustion structure according to claim 1, characterized in that, The diameter of the first air supply hole is set between 3mm and 25mm.

4. The biomass combustion structure according to claim 1, characterized in that, The diameter of the second air supply hole is set between 2mm and 20mm.

5. The biomass combustion structure according to claim 1, characterized in that, There are multiple first air supply holes, which are evenly distributed on the top surface of the upper air outlet end. The extension direction of each first air supply hole is perpendicular to the top surface of the upper air outlet end. There are also multiple second air supply holes, which are evenly distributed on the side surface of the upper air outlet end. The extension direction of each second air supply hole is perpendicular to the side surface of the upper air outlet end.

6. The biomass combustion structure according to claim 1, characterized in that, The slope angle of the side of the upper air outlet is set between 0° and 45°.

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