Biomass sawdust combustion furnace

Abstract

The utility model provides a kind of biomass sawdust combustion furnace, it is related to biomass sawdust fuel device technical field, including furnace body, combustion chamber, air supply device, slag baffle, flue gas passage, ash chamber, mixing device and flue gas pipe, the furnace body is horizontal cylinder, combustion chamber is arranged in furnace body, furnace body both ends are respectively provided with feed inlet and slag outlet, the furnace body on the one end of feed inlet is additionally provided with the igniter that extends into combustion chamber, air supply device is installed on furnace body side wall and is communicated with combustion chamber, ash chamber is arranged in the rear end combustion chamber of air supply device and is communicated with the slag outlet, slag baffle is movably installed between combustion chamber and ash chamber, flue gas passage is arranged above ash chamber, flue gas pipe is installed in furnace body top and is communicated with flue gas passage, mixing device is coaxially rotatably installed in combustion chamber, the present application can solve the problem of the current small and medium-sized biomass boiler or combustion furnace when burning sawdust exists and is provided with the problem of arching, arching and ash melting and wall sticking slag.

Description

Technical Field

[0001] This utility model relates to the technical field of biomass wood chip fuel devices, specifically to a biomass wood chip combustion furnace. Background Technology

[0002] Biomass fuel is a new type of clean fuel that uses agricultural and forestry waste as raw materials and can be directly burned. Wood chips are a widely used raw material for making biomass fuel and have good combustion performance.

[0003] Currently, small and medium-sized biomass boilers or combustion furnaces generally use fixed grates or simple horizontal cylindrical structures to burn wood chips. Due to the low density and large particle size range of wood chips, the following problems often occur during operation:

[0004] 1. Bridging and arching of feed material: Wood chips accumulate in the furnace to form "bridges and arches", resulting in discontinuous feeding and fluctuating flame size;

[0005] 2. The bed thickness is difficult to control, there is a lack of active material turning device, local oxygen deficiency and oxygen excess coexist, resulting in low combustion rate and poor thermal efficiency;

[0006] 3. Ash melting and wall adhesion: K, Na, and Cl in wood ash easily form low-melting-point salts above 800℃, which adhere to the furnace wall and affect heat exchange and lifespan.

[0007] Therefore, this application proposes a biomass wood chip combustion furnace. Utility Model Content

[0008] In order to overcome the problems in the background art, this utility model provides a biomass wood chip combustion furnace, which can solve the problems of feeding bridging and arching, feeding bridging and arching, as well as ash melting and wall adhesion and slag formation that exist when small and medium-sized biomass boilers or combustion furnaces burn wood chips.

[0009] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0010] A biomass wood chip combustion furnace includes a furnace body, a combustion chamber, an air supply device, a slag baffle, a flue gas passage, an ash chamber, a mixing device, and a flue gas pipe. The furnace body is a horizontal cylinder with a combustion chamber inside. A feed inlet and a slag discharge outlet are located at opposite ends of the furnace body. An igniter extending into the combustion chamber is also installed on the furnace body at the feed inlet end. The air supply device is installed on the side wall of the furnace body and communicates with the combustion chamber. The ash chamber is located within the combustion chamber at the rear end of the air supply device and communicates with the slag discharge outlet. The slag baffle is movably installed between the combustion chamber and the ash chamber. The flue gas passage is located above the ash chamber. The flue gas pipe is installed on the top of the furnace body and communicates with the flue gas passage. The mixing device is coaxially and rotatably installed within the combustion chamber.

[0011] Furthermore, the mixing device includes a rotating shaft, a mixer, and a motor. One end of the rotating shaft is connected to the power output end of the motor installed outside the furnace body, and the other free end of the rotating shaft extends into the combustion chamber through a bearing installed on the side wall of the ash chamber. The mixer is evenly installed on the rotating shaft inside the combustion chamber.

[0012] Furthermore, a material discharge roller is installed on the rotating shaft between the slag discharge port and the slag baffle plate. A set of partitions is installed at intervals on both sides of the material discharge roller. Baffles are installed alternately between the partitions above the material discharge roller. The partitions, baffles and the upper half of the material discharge roller form a flue gas channel connecting the combustion chamber and the flue gas pipe.

[0013] Furthermore, the slag baffle is a semi-circular cross-section of the combustion chamber. The slag baffle is coaxially mounted on the rotating shaft via a bearing. A limiting hole is provided on the slag baffle. A limiting rod that can move back and forth is installed on the discharge roller. The front end of the limiting rod corresponds to the limiting hole and can extend into the limiting hole. The projection of the rear end of the limiting rod corresponds to the slag discharge port.

[0014] Furthermore, the air supply device includes an air distribution chamber, an air inlet, and an air distribution pipe. The air distribution chamber is fixed to the furnace body, the air inlet is located on the shell of the air distribution chamber, and the air distribution pipe connects the air distribution chamber and the combustion chamber. The air distribution pipe is a tangential nozzle in the combustion chamber.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] 1. The mixing device 7 rotates coaxially, and the paddle mixer periodically agitates the wood chips, which can break up arches, even out the material, control the bed thickness, ensure the permeability of the fuel bed, and improve thermal efficiency.

[0017] 2. The tangential air supply and stirring positions of the air distribution pipe are staggered, forming a swirling and turbulent coupling, resulting in uniform oxygen distribution and a decrease in CO and black smoke.

[0018] 3. The material discharge roller and baffle form a rotating sweeping flue gas channel. Large particles of fly ash are intercepted by the baffle and fall into the ash chamber with the roller surface, avoiding ash accumulation and blockage in the flue and eliminating the need for manual ash removal.

[0019] 4. The scraping and turning actions of the mixer can peel off the early molten ash layer in real time, inhibit high-temperature adhesion, and the furnace can be operated for a long time without stopping the furnace to remove slag, thus extending the service life of the refractory lining. Attached Figure Description

[0020] To clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments are explained.

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0022] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0023] Figure 3 This is a schematic diagram of the cross-sectional structure of the present invention;

[0024] Figure 4 This is a schematic diagram of the air supply device of this utility model.

[0025] 1-Furnace body, 11-Feed inlet, 12-Slag discharge outlet, 13-Igniter, 2-Combustion chamber, 3-Air supply device, 31-Gas distribution chamber, 32-Air inlet, 33-Gas distribution pipe, 4-Slag baffle, 41-Limiting hole, 42-Limiting rod, 5-Flue gas passage, 51-Baffle, 52-Baffle, 6-Ash chamber, 7-Mixing device, 71-Rotating shaft, 72-Mixing device, 73-Motor, 74-Discharge roller, 8-Flue gas pipe. Detailed Implementation

[0026] To make the objectives, technical solutions, and beneficial effects of this utility model clearer, the preferred embodiments of this utility model will be described in detail below with reference to the accompanying drawings, so as to facilitate the understanding of those skilled in the art.

[0027] This utility model discloses a biomass wood chip combustion furnace, see reference. Figure 1-4 A biomass wood chip combustion furnace includes a furnace body 1, a combustion chamber 2, an air supply device 3, a slag baffle 4, a flue gas passage 5, an ash chamber 6, a mixing device 7, and a flue gas pipe 8. The furnace body 1 is a horizontal cylindrical structure. The combustion chamber 2 inside the furnace body 1 is used to burn wood chips. A feed inlet 11 and a slag discharge outlet 12 are respectively provided at both ends of the furnace body 1. The feed inlet 11 allows for the addition of wood chips, while the slag discharge outlet 12 facilitates the discharge of ash and slag. An igniter 13 extending into the combustion chamber 2 is also provided on the furnace body 1 at one end of the feed inlet 11 for ignition. The air supply device 3 is installed on the side wall of the furnace body 1 and communicates with the combustion chamber 2. The air supply system includes an ash chamber 6 located within the combustion chamber 2 at the rear end of the air supply device 3, connected to the ash discharge port 12. This chamber stores ash. A baffle plate 4 is movably installed between the combustion chamber 2 and the ash chamber 6 to separate them and prevent ash buildup. It can be opened when needed. A flue gas passage 5 is located above the ash chamber 6. A flue gas pipe 8 is installed at the top of the furnace body 1 and connected to the flue gas passage 5. The flue gas generated in the combustion chamber 2 can enter the flue gas pipe 8 through the flue gas passage 5. A mixing device 7 is coaxially rotated within the combustion chamber 2 to mix the wood chips, prevent feeding bridging, control bed thickness, and avoid ash sticking to the walls and forming slag.

[0028] See Figure 1-4The mixing device 7 includes a rotating shaft 71, a mixer 72, and a motor 73. One end of the rotating shaft 71 is connected to the power output end of the motor 73 installed outside the furnace body 1, which can drive the rotating shaft 71 to rotate. The other end of the rotating shaft 71 passes through the bearing installed on the side wall of the ash chamber 6 and extends into the combustion chamber 2. The mixer 72 is evenly installed on the rotating shaft 71 in the combustion chamber 2 in a paddle shape, which can mix the wood chips in the combustion chamber 2 to prevent feeding bridging, control the bed thickness, and scrape the wall to prevent ash from sticking to the wall and forming slag.

[0029] See Figure 1-4 A material discharge roller 74 is installed on the rotating shaft 71 between the slag discharge port 12 and the slag baffle plate 4. A set of partitions 51 are installed at intervals on both sides of the material discharge roller 74. Baffles 52 are installed alternately between the partitions 51 above the material discharge roller 74. The partitions 51, baffles 52 and the upper half of the roller surface of the material discharge roller 74 form a flue gas channel 5 that connects the combustion chamber 2 and the flue gas pipe 8. After the flue gas enters the flue gas channel 5 upward, large particles of dust can be blocked by the baffles 52 and fall down. Under the rotation of the material discharge roller 74, they are carried into the ash chamber 6, which can prevent ash accumulation in the flue gas channel 5 and eliminates the need for manual cleaning.

[0030] See Figure 1-4 The ash baffle plate 4 is a semi-circular cross-section of the combustion chamber 2. The ash baffle plate 4 is coaxially mounted on the rotating shaft 71 via a bearing. The ash baffle plate 4 has a limiting hole 41. A limiting rod 42 that can move back and forth is installed on the discharge roller 74. The front end of the limiting rod 42 corresponds to the limiting hole 41 and can extend into the limiting hole 41. The projection of the rear end of the limiting rod 42 corresponds to the ash discharge port 12. When the combustion chamber 2 is working, the ash baffle plate 4 is located in the lower half of the combustion chamber 2 due to gravity and friction, blocking the ash chamber 6. When ash removal is required, the limiting rod 42 is inserted into the limiting hole 41 through the ash discharge port 12. The ash baffle plate 4 can be rotated to the upper half of the combustion chamber 2 by the rotating shaft 71, which facilitates the cleaning of the ash at the bottom of the combustion chamber 2.

[0031] See Figure 1-4 The air supply device 3 includes an air distribution chamber 31, an air inlet 32, and an air distribution pipe 33. The air distribution chamber 31 is fixed to the furnace body 1. The air inlet 32 ​​is set on the shell of the air distribution chamber 31. The air distribution pipe 33 connects the air distribution chamber 31 and the combustion chamber 2. The air distribution pipe 33 is a tangential nozzle in the combustion chamber 2, which sprays air into the combustion chamber 2. The nozzle of the air distribution pipe 33 is staggered with the position of the agitator 72, so that the uniform air supply of the nozzle is not affected during the stirring process.

[0032] Work process:

[0033] A small amount of dry wood chips are added through the feed inlet 11, and the igniter 13 ignites them and, together with the air supply device 3, forms an initial flame, raising the furnace temperature to about 600℃.

[0034] A large quantity of wood chips enters the combustion chamber 2 through the feed inlet 11. The motor 73 of the mixing device 7 drives the rotating shaft 71, and the mixer 72 turns the wood chips, breaks up the arches and maintains a bed thickness of 100-150mm. The air distribution pipe 33 injects primary air tangentially, and the wood chips ignite rapidly.

[0035] High-temperature flue gas carries some fly ash upwards and is deflected at the discharge roller 74 and the staggered baffle 52. Large particles are blocked and enter the ash chamber 6 with the roller surface. The purified flue gas enters the top flue gas pipe 8 along the flue gas channel 5 and is led to the waste heat utilization or dust removal system.

[0036] Unburned solids and trapped fly ash settle into the ash chamber 6. The baffle plate 4 is in the lower half position, blocking the flow of ash and fuel and keeping the firebed clean;

[0037] When the ash chamber 6 is nearly full, the ash baffle 4 is flipped to the upper position by inserting the limiting rod 42 through the ash discharge port 12. At the same time, the rotating shaft 71 rotates at low speed, and the ash slides out naturally through the ash discharge port 12. After the ash discharge is completed, the limiting rod is removed, and the ash baffle returns to its original position under its own weight, and combustion continues.

[0038] When shutting down the furnace, cut off the air supply, but the furnace temperature can still be reduced by using the mixer at an inert speed. After the temperature drops, clean up the residual ash and check the wear of the refractory lining and the mixer.

[0039] This combustion furnace can achieve multiple functions such as continuous and stable combustion, automatic dust removal, and convenient ash discharge in a horizontal and compact structure, making it very suitable for wood chip biomass hot blast furnace applications.

[0040] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A biomass wood chip combustion furnace, characterized in that: The biomass wood chip combustion furnace includes a furnace body (1), a combustion chamber (2), an air supply device (3), a slag baffle (4), a flue gas passage (5), an ash chamber (6), a mixing device (7), and a flue gas pipe (8). The furnace body (1) is a horizontal cylinder. The combustion chamber (2) is set inside the furnace body (1). The furnace body (1) has a feed inlet (11) and a slag discharge outlet (12) at both ends. An igniter (13) extending into the combustion chamber (2) is also set on the furnace body (1) at one end of the feed inlet (11). The air supply device (3) is installed on the side wall of the furnace body (1) and communicates with the combustion chamber (2). The ash chamber (6) is set in the combustion chamber (2) at the rear end of the air supply device (3) and communicates with the slag discharge port (12). The baffle plate (4) is movably installed between the combustion chamber (2) and the ash chamber (6). The flue gas passage (5) is set above the ash chamber (6). The flue gas pipe (8) is installed on the top of the furnace body (1) and communicates with the flue gas passage (5). The mixing device (7) is coaxially rotated in the combustion chamber (2).

2. The biomass wood chip combustion furnace according to claim 1, characterized in that: The mixing device (7) includes a rotating shaft (71), a mixer (72) and a motor (73). One end of the rotating shaft (71) is connected to the power output end of the motor (73) installed outside the furnace body (1). The other free end of the rotating shaft (71) passes through the bearing installed on the side wall of the ash chamber (6) and extends into the combustion chamber (2). The mixer (72) is evenly installed on the rotating shaft (71) inside the combustion chamber (2).

3. The biomass wood chip combustion furnace according to claim 2, characterized in that: A material discharge roller (74) is installed on the rotating shaft (71) between the slag discharge port (12) and the slag baffle (4). A set of partitions (51) are installed on both sides of the material discharge roller (74) at intervals. Baffles (52) are installed alternately between the partitions (51) above the material discharge roller (74). The partitions (51), baffles (52) and the upper half of the roller surface of the material discharge roller (74) constitute a flue gas passage (5) connecting the combustion chamber (2) and the flue gas pipe (8).

4. The biomass wood chip combustion furnace according to claim 2, characterized in that: The slag baffle (4) is a semi-circular cross section of the combustion chamber (2). The slag baffle (4) is coaxially mounted on the rotating shaft (71) through a bearing. A limiting hole (41) is opened on the slag baffle (4). A limiting rod (42) that can move back and forth is installed on the discharge roller (74). The front end of the limiting rod (42) corresponds to the limiting hole (41) and can extend into the limiting hole (41). The projection of the rear end of the limiting rod (42) corresponds to the slag discharge port (12).

5. The biomass wood chip combustion furnace according to claim 1, characterized in that: The air supply device (3) includes an air distribution chamber (31), an air inlet (32) and an air distribution pipe (33). The air distribution chamber (31) is fixed to the furnace body (1). The air inlet (32) is set on the shell of the air distribution chamber (31). The air distribution pipe (33) connects the air distribution chamber (31) and the combustion chamber (2). The air distribution pipe (33) is a tangential nozzle in the combustion chamber (2).

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