A biomass fuel gasification furnace

Abstract

This invention provides a biomass fuel gasifier, comprising a cylindrical furnace body, a feeding device, and a gas extraction device. The furnace body includes a combustion chamber, a gas purification chamber, and a tar processor. The tar processor is located within the gas purification chamber and includes a top ash outlet at its upper end, extending out of the furnace body. The top ash outlet is equipped with an openable and closable sealing cover. This invention, by providing a top ash outlet for the tar processor, enables immersion cleaning or brushing of the processor's pipes, improving cleaning convenience and reducing the risk of blockage. Placing the tar processor within the gas purification chamber reduces damage to the processor, extends its service life, and enhances the gasification effect on tar in the flue gas. This solution ensures effective biomass gasification and tar cracking in the flue gas, resulting in a pale blue or pale yellow flame with no black smoke, thus improving environmental protection.

Description

Technical Field

[0001] This invention relates to the field of biomass energy utilization technology, and in particular to a biomass fuel gasification furnace. Background Technology

[0002] The raw materials used in biomass gasification furnaces are wide-ranging, including byproducts from agricultural production, which can also improve environmental protection. Examples include wheat straw, corn stalks, corn husks, and rice straw. However, biomass combustion produces tar in the flue gas. To ensure the proper pyrolysis and gasification of this tar, a tar processor is needed to treat the flue gas. Conventional tar processors include:

[0003] 1. Electromagnetic induction heating tar processor: Uses electromagnetic induction heating to separate tar from impurities, thereby achieving tar cleaning and recovery; Vacuum distillation tar processor: Utilizes vacuum distillation technology to separate tar from other impurities, thereby achieving tar purification and recovery. Both of these tar processors require electric heating for processing, which is not conducive to energy conservation.

[0004] 2. Activated carbon tar adsorption processor: Activated carbon is used to adsorb tar and other harmful substances, and then the activated carbon is cleaned and reused through backwashing or regeneration; this type of tar processor is prone to clogging and has extremely high maintenance costs.

[0005] The dust inside conventional tar processors is usually formed by the sedimentation of tar and other impurities. If it is not cleaned for a long time, it may clog pipes and cause safety hazards. In the original equipment (application number CN2021113835589), the tar processor decomposes the tar in the flue gas back into gas at high temperature. However, the installation of this fuel dispenser is as follows: one end is located at the waist of the maintenance passage, and the other end extends through the waist of the fuel tank into the tar gas purification chamber, with a portion located in the combustion chamber. This has the following defects during use:

[0006] 1. Prolonged use can easily cause blockage of the tar processor tube, making it difficult or impossible to clean the inside of the tar processor. This results in frequent replacement of the tar processor and high maintenance and repair costs.

[0007] 2. Placing a portion of the tar processor within the combustion chamber exposes it to high temperatures and makes it susceptible to oxidation by post-combustion oxides. This can easily cause perforations in the tar processor, affecting its effectiveness in tar gasification and its service life.

[0008] In addition, the biomass gasifier wastes a lot of heat after burning the raw materials, which is an urgent problem to be solved and optimized. Summary of the Invention

[0009] The purpose of this invention is to overcome the above-mentioned shortcomings of the prior art and provide a biomass fuel gasifier that facilitates cleaning of the tar processor, improves the service life of the tar processor and the gasification effect of tar in flue gas, reduces the concentrated accumulation of biomass raw materials in the gasifier, and improves the biomass combustion efficiency and heat utilization rate.

[0010] The technical solution of the present invention is: a biomass fuel gasification furnace, comprising a cylindrical furnace body, a feeding device and a gas extraction device, wherein the furnace body is provided with a combustion chamber, a gas purification chamber and a tar processor, the tar processor is disposed in the gas purification chamber and the gas purification chamber is connected to the gas extraction device, the tar processor includes a top ash outlet disposed at its upper end, the top ash outlet extends out of the furnace body from the top of the furnace body, and the top ash outlet is provided with an openable and closable sealing cover.

[0011] Preferably, an ash outlet is provided at the top of the tar processor to clean the inside of the tar processor, thereby preventing the tar processor from being blocked by the solidification and accumulation of tar and dust in the flue gas after long-term use.

[0012] Furthermore, the tar processor also includes several tar vaporization pipes and several buffers. The buffers are arranged horizontally, and the tar vaporization pipes are connected to the buffers in a "π" shape. The tar vaporization pipes and buffers are installed close to the inner wall of the gas purification chamber. Multiple "π"-shaped series connections of the tar vaporization pipes and buffers ensure sufficient vaporization of the tar within the vaporization pipes, ultimately forming ash. The tar processor's close proximity to the inner wall of the gas purification chamber maintains the optimal temperature for tar vaporization, thereby improving the tar cracking efficiency.

[0013] Furthermore, the tar processor also includes a gas inlet at one end of the tar gasification pipe, a gas outlet on the buffer, and a bottom ash outlet. The gas inlet is connected to the upper end of the combustion chamber, the gas outlet is located on the buffer at the lower end of the gas purification chamber and is connected to the gas purification chamber, and the bottom ash outlet extends to the outside of the furnace body. The bottom ash outlet is provided with an openable and closable cover.

[0014] Furthermore, the gas inlet is connected to the first buffer via a first vaporization pipe, a second buffer is provided above the first buffer, a third buffer is provided on one side of the first buffer, a second vaporization pipe is provided between the first buffer and the second buffer, and a third vaporization pipe is provided between the second buffer and the third buffer.

[0015] Furthermore, the first and third buffers are located on the same horizontal plane, and the position of the second buffer is at or above the gas inlet.

[0016] Preferably, the second buffer is positioned higher than the gas inlet, so that the cleaning or soaking process of the tar processor with cleaning fluid is not affected by the lower gas inlet, and other outlets are sealed before cleaning; more preferably, the gas outlet is provided with a zigzag pipe, the uppermost end of which is level with or higher than the gas inlet, thereby improving the effect of soaking and cleaning the inside of the tar processor.

[0017] Furthermore, the feeding device includes a fuel hopper and a fuel separator. The fuel separator is located at the top of the furnace body. The fuel hopper and the fuel separator are connected by a screw feeder. A tapered separator is provided at the lower end of the fuel separator.

[0018] Preferably, the tapered separator facilitates the dispersion of the combustion separator feed, avoiding concentrated accumulation in the same location within the combustion chamber and improving the combustion efficiency of the raw materials.

[0019] Furthermore, the exhaust device includes an exhaust pipe connected to the gas purification chamber, an oxygenation hole and an exhaust fan on the exhaust pipe, and a flame head at the outlet of the exhaust fan, with an igniter inside the flame head.

[0020] Preferably, both the exhaust pipe and the burner of the exhaust device are equipped with an insulation layer to ensure that the gas temperature during the transportation process is not affected by the outside environment, thereby improving the ignition and combustion effect.

[0021] Furthermore, the lower end of the combustion chamber is a cone, and the cone is provided with a tapered gas hole combustion head. The upper end of the combustion chamber is a gas collection chamber, and a furnace bridge is provided below the combustion head. The lower end of the furnace bridge is an ash collection bin. One side of the ash collection bin is provided with an ash outlet, and the other side is provided with a combustion aid fan outlet. An ignition port is provided on one side of the cone.

[0022] Furthermore, the furnace body is equipped with a waste water tank, and a first insulation layer and a second insulation layer are provided between the gas purification chamber and the waste water tank, and a third insulation layer is provided around the waste water tank.

[0023] Preferably, the first and second insulation layers mainly insulate the gas purification chamber and also isolate the low temperature in the waste water tank to ensure the temperature of the gas purification chamber. The third insulation layer mainly insulates the waste water tank and the furnace body to prevent high temperatures from appearing on the outer surface of the furnace body.

[0024] Furthermore, a float valve level controller connected to the waste water tank is installed on the outside of the furnace body. The float valve level controller allows for direct observation of the water level in the waste water tank and can also automatically control the water supply to the waste water tank.

[0025] The present invention has the following beneficial effects:

[0026] 1. By setting a top ash outlet at the top of the tar processor, the pipes of the tar processor can be soaked and cleaned or brushed, which improves the convenience of cleaning the tar processor and reduces the risk of blockage. In addition, placing the tar processor in the gas purification chamber avoids leakage after prolonged high-temperature burning, reduces damage to the tar processor, and improves its service life and the gasification effect of tar in flue gas.

[0027] 2. The cone separator improves the uniform distribution of material entering the combustion chamber, effectively improving the gasification efficiency of raw materials and avoiding concentrated accumulation;

[0028] 3. The furnace body adopts a multi-layer design, which improves the utilization of waste heat and the heat preservation effect, while reducing the impact of high temperature on the outside environment and ensuring the safe use of the furnace body.

[0029] This solution features a simple structure and ingenious design, ensuring the effective biomass gasification and tar cracking in the flue gas. It also results in a light blue or light yellow flame with no black smoke, effectively improving environmental protection.

[0030] The detailed structure of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0031] Figure 1 - This is a schematic diagram of the structure of the present invention;

[0032] Figure 2 - A schematic diagram of the top of the tar processor inside the furnace;

[0033] Figure 3 - A schematic diagram of the bottom of the tar processor inside the furnace;

[0034] Figure 4 - A schematic diagram of the tar processor structure;

[0035] Figure 5 - A schematic diagram of another structure for a tar processor;

[0036] 1-Fuel separator, 2-Top ash outlet, 3-Second buffer, 4-First insulation layer, 5-Second insulation layer, 6-Residual heat tank, 7-Third insulation layer, 8-Burner, 9-Exhaust fan, 10-Oxygenation hole, 11-Exhaust pipe, 12-Bottom ash outlet, 13-Drain outlet, 14-Ash collection bin, 15-Furnace bridge, 16-Cone, 17-Combustion burner, 18-Support leg, 19-Ash outlet, 20-Water outlet pipe, 21-Ignition port, 22-Gas purification chamber, 23-Gas collection chamber, 24-Conical separator, 25-Cylinder, 26-Float valve water level controller, 27-Screw conveyor, 28-Fuel hopper, 29-First gasification pipe, 30-Second gasification pipe, 31-Third gasification pipe, 32-Ash outlet of gas purification chamber, 33-Third buffer, 34-First buffer, 35-Gas outlet. Detailed Implementation

[0037] As shown in the attached figure: A biomass fuel gasifier includes a cylindrical furnace body, a feeding device, and a gas extraction device. The bottom of the furnace body is provided with support legs 18. The furnace body is provided with a combustion chamber, a gas purification chamber 22, and a tar processor. The temperature of the combustion chamber is 1000-1200℃, and the temperature of the gas purification chamber 22 is 700-850℃. The tar processor is located in the gas purification chamber 22, which is connected to the gas extraction device. The tar processor includes a top ash outlet 2 located at its upper end, which extends out of the furnace body. The top ash outlet 2 is provided with an openable and closable sealing cover. An ash outlet 19 is provided at the top of the tar processor to clean the inside of the tar processor and prevent the tar processor from being blocked by the solidification and accumulation of fully gasified tar and dust in the flue gas after long-term use. The top ash outlet 2 can also provide oxygen to the gas after pyrolysis when the biomass raw materials are low in oil and the tar is fully pyrolyzed. It can also preheat the incoming air through the tar processor and the gas purification chamber 22 to ensure the gas combustion efficiency after biomass gasification.

[0038] In this embodiment, the tar processor further includes several tar vaporization pipes and several buffers. The buffers are arranged horizontally, and the tar vaporization pipes and buffers are connected alternately in a "π" shape. The tar vaporization pipes and buffers are arranged close to the inner wall of the gas purification chamber 22. The tar vaporization pipes and buffers can form a whole or combination of multiple "π" shapes connected in series, or form six sets of tar processors by connecting multiple "π" shapes in series. The "π" shape arrangement ensures that the tar is fully vaporized in the vaporization pipes, and the tar eventually forms ash. The tar processors are close to the inner wall of the gas purification chamber 22 to ensure the temperature for tar vaporization and improve the tar cracking efficiency. To further improve the cracking efficiency of the tar processors, the tar processors are arranged in an arc shape.

[0039] In this embodiment, the tar processor further includes a gas inlet at one end of the tar gasification pipe, a gas outlet 35 on the buffer, and a bottom ash outlet 12. The gas inlet is connected to the upper end of the combustion chamber, the gas outlet 35 is located on the buffer at the lower end of the gas purification chamber 22 and is connected to the gas purification chamber 22, and the bottom ash outlet 12 extends to the outside of the furnace body and is provided with an openable and closable cover. Preferably, the gas inlet is connected to the first buffer 34 through the first gasification pipe 29, a second buffer 3 is provided above the first buffer 34, a third buffer 33 is provided on one side of the first buffer 34, a second gasification pipe 30 is provided between the first buffer 34 and the second buffer 3, and a third gasification pipe 31 is provided between the second buffer 3 and the third buffer 33.

[0040] In this embodiment, the first buffer 34 and the third buffer 33 are located on the same horizontal plane, and the position of the second buffer 3 is level with or higher than the gas inlet. Preferably, the second buffer 3 is positioned higher than the gas inlet, so that it is not affected by the lower gas inlet during the cleaning or soaking of the tar processor with cleaning fluid, and other outlets are sealed before cleaning. More preferably, in another embodiment, the gas outlet 35 is provided with a zigzag pipe, the uppermost end of which is level with or higher than the gas inlet, improving the effect of soaking and cleaning the inside of the tar processor. Preferably, the bottom of the gas purification chamber 22 is provided with a gas purification chamber ash outlet 32 ​​to reduce the amount of dust in the gas.

[0041] In this embodiment, the feeding device includes a fuel hopper 28 and a fuel separator 1. The fuel separator 1 is located at the top of the furnace body. The fuel hopper 28 and the fuel separator 1 are connected by a screw feeder. A tapered separator 24 is provided at the lower end of the fuel separator 1. Both the fuel hopper 28 and the fuel separator 1 can store raw materials. The upper end of the tapered separator 24 is driven up and down by a cylinder 25 installed and fixed inside the fuel separator 1. The tapered separator 24 controls the opening and closing of the discharge port at the lower end of the fuel separator 1. During the closing process, it can seal the discharge port of the fuel separator 1 to prevent gas leakage. Preferably, the tapered separator 24 facilitates the dispersion of the material discharged from the combustion separator, preventing raw materials from accumulating in the same position in the combustion chamber, thereby improving the combustion efficiency of the raw materials. The outer surface of the fuel separator 1 is equipped with a hoisting device to improve the transfer and installation of the furnace body.

[0042] In this embodiment, the extraction device includes an extraction pipe 11 connected to the gas purification chamber 22. The extraction pipe 11 is equipped with an oxygenation port 10 and an extraction fan 9. The oxygenation port 10 is equipped with a cover plate that allows for adjustable oxygen intake. The outlet of the extraction fan 9 is equipped with a burner 8, which contains an igniter. Preferably, both the extraction pipe 11 and the burner 8 of the extraction device are provided with heat insulation layers to ensure that the temperature of the extracted gas is not affected by external factors, thereby improving the ignition rate and combustion efficiency.

[0043] In this embodiment, the lower end of the combustion chamber is a cone 16, and the cone 16 is provided with a tapered gas hole combustion head 17. The upper end of the combustion chamber is a gas collecting chamber 23, which is connected to the gas purification chamber 22 through a tar processor. Below the combustion head 17 is a furnace bridge 15, and the lower end of the furnace bridge 15 is an ash collection bin 14. One side of the ash collection bin 14 is provided with an ash outlet 19, and the ash outlet 19 is provided with a cover plate. The other side of the ash collection bin 14 is provided with a combustion air blower outlet, and the lower end of the combustion air blower outlet is provided with a drain outlet 13. One side of the cone 16 is provided with an ignition port 21.

[0044] In this embodiment, a waste water tank 6 is provided inside the furnace body. A first insulation layer 4 and a second insulation layer 5 are provided between the gas purification chamber 22 and the waste water tank 6. A third insulation layer 7 is provided around the waste water tank 6. Preferably, the first insulation layer 4 and the second insulation layer 5 mainly insulate the gas purification chamber 22 and also isolate the low temperature in the waste water tank 6 to maintain the temperature of the gas purification chamber 22. The third insulation layer 7 mainly insulates the waste water tank 6 and insulates the furnace body to prevent high temperatures from appearing on the outer surface of the furnace body. More preferably, a float valve water level controller 26 connected to the waste water tank 6 is provided on the outside of the furnace body. The float valve water level controller 26 allows for direct observation of the water level in the waste water tank 6 and can automatically control the water intake into the waste water tank 6. A water outlet pipe 20 with a valve is provided at the lower end of the waste water tank 6, and the water outlet pipe 20 extends to the outside of the furnace body.

[0045] In the process of using this invention, first check whether the waste water tank 6 is full of water, then add the raw materials to the fuel hopper 28, and transport the raw materials to the fuel separator 1 through the screw conveyor 27. The cylinder 25 controls the cone separator 24 to move downward, so that the raw materials fall into the combustion chamber. Ignite the raw materials from the ignition port 21, and slowly start the combustion fan. Close all the ash outlets 19 on the furnace body and stop the fuel feeding. After burning for 2-5 minutes, raise the temperature of the combustion chamber to above 800°C and start the exhaust fan 9. Ignite the gas of the flame head 8 through the igniter. Adjust the air intake of the oxygenation port 10 according to the color of the flame of the flame head 8 so that the flame color is light yellow or bluish. The air intake can also be controlled by adjusting the ash outlet 2 at the top of the tar processor to ensure complete combustion of the fuel gas. After the flame is stable, the fuel can be continuously fed.

[0046] This invention, by setting a top ash outlet 2 at the top of the tar processor, enables immersion cleaning or brushing of the processor's pipes, improving cleaning convenience and reducing the risk of blockage. Furthermore, placing the tar processor within the gas purification chamber 22 prevents leaks after prolonged high-temperature burning, reducing damage and extending its service life and tar gasification efficiency. The conical separator 24 improves the even distribution of material entering the combustion chamber, effectively increasing the gasification efficiency of raw materials and preventing concentrated accumulation. The multi-layered furnace body enhances waste heat utilization and insulation, while reducing the impact of high temperatures on the external environment, ensuring safe furnace operation.

[0047] This scheme has a simple structure and ingenious design, which ensures the effectiveness of the furnace body in biomass gasification and the cracking effect of tar in flue gas. It makes the flame color of the 8th burner light blue or light yellow, with no black smoke, which effectively improves environmental protection.

[0048] The above description describes the preferred embodiments of the present invention and the technical principles applied thereto. For those skilled in the art, any obvious changes such as equivalent transformations or simple substitutions based on the technical solutions of the present invention, without departing from the spirit and scope of the present invention, shall fall within the protection scope of the present invention.

Claims

1. A biomass fuel gasification furnace, comprising a furnace body, a feeding device, and a gas extraction device, wherein the furnace body is provided with a combustion chamber, a gas purification chamber, and a tar processor, characterized in that: The tar processor includes a top ash outlet located at its upper end; The tar processor also includes several tar vaporization pipes and several horizontally arranged buffers, with the tar vaporization pipes and buffers connected in a "π" shape. The tar processor also includes a gas inlet located at one end of the tar gasification pipe and a gas outlet located on the buffer. The gas inlet is connected to the upper end of the combustion chamber, and the gas outlet is connected to the gas purification chamber.

2. The biomass fuel gasification furnace according to claim 1, characterized in that: The top ash outlet extends out of the furnace body and is equipped with an openable and closable sealing cover.

3. The biomass fuel gasification furnace according to claim 1, characterized in that: The tar processor is located in a gas purification chamber, which is connected to an exhaust system.

4. The biomass fuel gasification furnace according to claim 3, characterized in that: The tar gasification pipe and buffer are installed close to the inner wall of the gas purification chamber.

5. The biomass fuel gasification furnace according to claim 1, characterized in that: The buffer is also provided with a bottom ash outlet, which extends to the outside of the furnace body and is provided with an openable and closable cover.

6. The biomass fuel gasification furnace according to claim 1, characterized in that: The gas inlet is connected to the first buffer via a first vaporization pipe. A second buffer is provided above the first buffer, and a third buffer is provided on one side of the first buffer. A second vaporization pipe is provided between the first buffer and the second buffer, and a third vaporization pipe is provided between the second buffer and the third buffer; or the first buffer and the third buffer are located on the same horizontal plane, and the position of the second buffer is level with or higher than the gas inlet.

7. The biomass fuel gasification furnace according to claim 1, characterized in that: The feeding device includes a fuel hopper and a fuel separator. The fuel separator is located at the top of the furnace body. The fuel hopper and the fuel separator are connected by a screw feeder. A tapered separator is provided at the lower end of the fuel separator.

8. The biomass fuel gasification furnace according to claim 1, characterized in that: The exhaust device includes an exhaust pipe connected to the gas purification chamber. The exhaust pipe is equipped with an oxygenation hole and an exhaust fan. The exhaust fan outlet is equipped with a flame head, and the flame head contains an igniter.

9. The biomass fuel gasification furnace according to claim 1, characterized in that: The lower end of the combustion chamber is a cone with a tapered gas hole combustion head. The upper end of the combustion chamber is a gas collection chamber. Below the combustion head is a furnace bridge. The lower end of the furnace bridge is an ash collection bin. One side of the ash collection bin has an ash outlet, and the other side has a combustion air blower outlet. One side of the cone has an ignition port.

10. The biomass fuel gasification furnace according to claim 1, characterized in that: The furnace body is equipped with a waste water tank, and a first insulation layer and a second insulation layer are provided between the gas purification chamber and the waste water tank. A third insulation layer is provided around the waste water tank.

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