Biomass self-driven pyrolysis heat supply method and equipment for grain drying

Abstract

The invention discloses novel equipment and method for drying grains through biomass self-driven pyrolysis heat supply, and the biomass self-driven pyrolysis heat supply equipment for drying grains mainly comprises a feeding hopper, a feeding conveying device, a self-driven biomass pyrolysis furnace, combustion-gas distribution integrated equipment, an air pipe, a control box and other units. A biomass pyrolysis gasification combustion heat supply technology is adopted, combustible pyrolysis gas generated by biomass gasification is directly used for drying grains after sufficient combustion and air distribution, compared with a traditional indirect heat exchange air supply technology for grain drying, the heat utilization efficiency is higher, the main furnace of the novel equipment adopts a reciprocating grate furnace structure form, and the energy consumption is low. The method is suitable for various biomass raw materials such as rice / wheat straw, landscaping garbage, waste wood chips and biomass particles, the adaptability of the raw materials is wider, resource utilization of organic solid waste is achieved, and the raw material cost and the operation cost of grain drying are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of grain drying, and particularly to a biomass self-driven pyrolysis heating method and equipment for grain drying. Background Art

[0002] In the process of grain production and storage, the drying link is crucial for ensuring grain quality and extending the storage time. Traditional grain drying methods mostly rely on fossil energy, which not only has high costs but also causes environmental pollution problems. With the enhancement of environmental awareness and the promotion of the concept of sustainable development, the development and utilization of clean energy grain drying equipment has become an inevitable trend in the industry.

[0003] Currently, grain drying mainly uses natural gas for heating or a hot blast stove heating process that is only applicable to biomass pellet fuels. The fuel is single and the cost is high. The adoption of biomass pyrolysis gasification heating technology and equipment, using biomass solid wastes such as straw and garden greening waste as fuels, promotes the circular, low-carbon, clean, and efficient reuse of solid waste resources, providing a new solution for the grain drying field. Therefore, those skilled in the art provide a biomass self-driven pyrolysis heating method and equipment for grain drying to solve the problems raised in the above background art. Summary of the Invention

[0004] The purpose of the present invention is to solve the disadvantages existing in the prior art, and to provide a biomass self-driven pyrolysis heating method and equipment for grain drying.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A biomass self-driven pyrolysis heating method for grain drying, comprising the following steps: S1: The biomass is broken and placed into the feeding hopper, and then sent into the self-driven biomass pyrolysis furnace through the feeding conveying device. Then, it is ignited through the ignition door in sequence, and the oxygen content in the self-driven biomass pyrolysis furnace is controlled by the primary air blower. With the help of the calorific value of the biomass itself, its self-driven pyrolysis gasification is realized, and the ash residue after the reaction is discharged through the mechanical ash auger. S2: The combustible gas generated during the biomass gasification process is introduced into the combustion chamber and fully burned by blowing air through the secondary air blower. After removing organic pollutants such as tar, the generated high-temperature hot flue gas is introduced into the air mixing chamber, and cold air is supplemented by the air distribution valves on both sides of the air mixing chamber to make the high-temperature hot flue gas and cold air fully mixed, and the hot air temperature after air distribution is controlled at 50 - 65 °C. S3: The hot air after air distribution is directly introduced into the grain dryer through the air duct for grain drying, and then discharged up to standard after waste gas treatment.

[0006] As a further solution of the present invention, in the step S1, the temperature of biomass pyrolysis and gasification should be controlled at 650-800 °C, and the negative pressure in the furnace should be controlled at -50 - -200 Pa; in the step S2, the temperature of the combustion chamber is not lower than 850 °C.

[0007] As a further solution of the present invention, the feeding and conveying device, the primary fan, the secondary fan, and the air distribution valve are all controlled by frequency conversion. Temperature monitoring probes are provided at the outlets of the self-driven biomass pyrolysis furnace, the combustion chamber, the air distribution chamber, and the inlet duct of the grain dryer. The opening degree of the air distribution valve and the temperature of the outlet duct of the air distribution chamber are automatically linked and controlled, and the feeding and conveying device is linked and controlled with the temperature inside the self-driven biomass pyrolysis furnace.

[0008] A biomass self-driven pyrolysis heating equipment for grain drying mainly includes units such as a feeding hopper, a feeding and conveying device, a self-driven biomass pyrolysis furnace, a combustion-gas distribution integrated device, an air duct, and a control box. As a further solution of the present invention, the feeding hopper, the feeding and conveying device, and the self-driven biomass pyrolysis furnace are connected end to end in sequence. The flue gas pipeline of the self-driven biomass pyrolysis furnace is inserted into the combustion-gas distribution integrated device, and the air duct is connected to the top of the combustion-gas distribution integrated device.

[0009] As a further solution of the present invention, the self-driven biomass pyrolysis furnace adopts a reciprocating grate furnace structure form, and an ignition door is provided on its side wall.

[0010] As a further solution of the present invention, the combustion-gas distribution integrated device includes a combustion chamber and an air distribution chamber. A porous baffle is used to separate the combustion chamber and the air distribution chamber in the middle, and the air duct is connected to the top of the air distribution chamber.

[0011] As a further solution of the present invention, a dust cleaning port is provided at the bottom of the combustion chamber.

[0012] As a further solution of the present invention, a plurality of air holes are provided on the porous baffle. The shape of the air holes is square, and the total area of the opened air holes accounts for 20-40% of the area of the porous baffle.

[0013] As a further solution of the present invention, two groups of air distribution valves are symmetrically arranged on both sides of the air distribution chamber, and one of the groups is manually controlled.

[0014] The beneficial effects of the present invention are: The present invention adopts the biomass pyrolysis gasification combustion heating technology process. After the combustible pyrolysis gas generated by biomass gasification is fully burned and air is supplied, it is directly used for drying grains. Compared with the traditional indirect heat exchange air supply process for grain drying, the heat utilization efficiency is higher. In addition, the main furnace of the new equipment adopts a reciprocating grate furnace structure form, which can be applied to various biomass raw materials such as rice / wheat straw, garden greening waste, waste wood chips, and biomass pellets, with a wider raw material adaptability, which is conducive to realizing the resource utilization of organic solid waste. The equipment uses the self-heating value of biomass raw materials for self-driven pyrolysis heating, without the need to add auxiliary fossil fuels such as diesel and natural gas, which is conducive to reducing the raw material cost and operation cost of grain drying. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 FIG. is a floor plan layout diagram of a biomass self-driven pyrolysis heating method and equipment for grain drying proposed by the present invention; Figure 2 FIG. is a process flow diagram of a biomass self-driven pyrolysis heating method and equipment for grain drying proposed by the present invention; Figure 3 FIG. is a three-view structure diagram of a combustion-air distribution integrated device of a biomass self-driven pyrolysis heating method and equipment for grain drying proposed by the present invention.

[0016] In the figure: 1. Hopper; 2. Feeding conveyor; 3. Self-driven biomass pyrolysis furnace; 31. Ash auger; 32. Primary air blower; 34. Flue gas pipe; 35. Ignition door; 4. Combustion-air distribution integrated device; 41. Combustion chamber; 411. Ash cleaning port; 42. Air distribution chamber; 421. Air distribution valve; 43. Porous retaining wall; 44. Air holes; 5. Air duct; 6. Control box. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. It should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "setting" should be understood in a broad sense. For those of ordinary skill in the art, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0018] Refer to Figures 1 - 3 , a biomass self-driven pyrolysis heating method for grain drying, comprising the following steps: S1: The biomass is crushed and put into the feeding hopper 1, and then sent into the self-driven biomass pyrolysis furnace 3 through the feeding conveyor device 2. Subsequently, it is ignited through the ignition door 35, and the oxygen content in the self-driven biomass pyrolysis furnace 3 is controlled by the primary air blower 32. By means of the calorific value of the biomass itself, its self-driven pyrolysis gasification is realized. The ash residue after the reaction is discharged through the mechanical ash auger 31; S2: The combustible gas generated during the biomass gasification process is introduced into the combustion chamber 41 and fully burned by blowing air through the secondary air blower 33. After removing organic pollutants such as tar, the generated high-temperature hot flue gas is introduced into the air mixing chamber 42, and cold air is supplemented by using the air distribution valves 421 / 422 on both sides of the air mixing chamber 42, so that the high-temperature hot flue gas is fully mixed with the cold air, and the temperature of the hot air after air distribution is controlled at 50 - 65 °C; S3: The hot air after air distribution is directly introduced into the grain dryer through the air duct 5 for grain drying, and then discharged up to standard after waste gas treatment.

[0019] In the present invention, in step S1, the biomass pyrolysis gasification temperature should be controlled at 650 - 800 °C, and the negative pressure in the furnace is controlled at -50 - -200 Pa; in step S2, the temperature of the combustion chamber 41 is not lower than 850 °C.

[0020] In the present invention, the feeding conveyor device 2, the primary air blower 32, the secondary air blower 33, and the air distribution valve 421 all adopt frequency conversion control. Temperature monitoring probes are provided at the outlets of the self-driven biomass pyrolysis furnace 3, the combustion chamber 41, the air mixing chamber 42 air duct 5, and the inlet air duct of the grain dryer. The specific structure and principle of the temperature monitoring probe already belong to the prior art, and those skilled in the art can use it in cooperation with other electrical components outside. Therefore, no excessive elaboration is made. Its temperature monitoring probe is mainly used for real-time monitoring of the hot air temperature, and the opening degree of the air distribution valve 421 and the temperature of the air duct 5 at the outlet of the air mixing chamber 42 are automatically linked and controlled, and the feeding conveyor device 2 and the temperature in the self-driven biomass pyrolysis furnace 3 are linked and controlled.

[0021] A biomass self-driven pyrolysis heating equipment for grain drying mainly includes units such as a feeding hopper 1, a feeding conveyor device 2, a self-driven biomass pyrolysis furnace 3, a combustion-gas distribution integrated device 4, an air duct 5, and a control box 6, etc.; In particular, the feeding hopper 1, the feeding conveyor device 2, and the self-driven biomass pyrolysis furnace 3 are connected end to end in sequence. The flue gas pipe 34 of the self-driven biomass pyrolysis furnace 3 is inserted into the combustion-gas distribution integrated device 4, and the air duct 5 is connected to the top of the combustion-gas distribution integrated device 4.

[0022] In the present invention, the self-driven biomass pyrolysis furnace 3 adopts a reciprocating grate furnace structure form, and its side wall is provided with an ignition door 35.

[0023] In particular, the combustion-air distribution integrated device 4 includes a combustion chamber 41 and an air distribution chamber 42. A porous partition wall 43 is used to separate the combustion chamber 41 and the air distribution chamber 42 in the middle, and the air duct 5 is connected to the top of the air distribution chamber 42.

[0024] In the present invention, an ash cleaning port 411 is provided at the bottom of the combustion chamber 41, and the ash generated after combustion in the combustion chamber 41 can be discharged from the ash cleaning port 411.

[0025] In particular, a plurality of air holes 44 are provided on the porous partition wall 43. The shape of the air holes 44 is square, and the total area of the air holes 44 accounts for 20-40% of the area of the porous partition wall 43.

[0026] In the present invention, two groups of air distribution valves 421 / 422 are symmetrically arranged on both sides of the air distribution chamber 42. One group is manually controlled, and the flow rate of the cold air entering the air distribution chamber 42 can be adjusted by controlling the air distribution valve 421.

[0027] In addition, in the present invention, the biomass raw materials include various biomass raw materials such as rice / wheat straw, garden greening waste, waste wood chips, wood chips, and biomass pellets.

[0028] In this application, the structures and connection relationships not described in detail are all prior arts, and their structures and principles are well-known technologies, so they will not be elaborated here.

[0029] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A biomass self-driven pyrolysis heating method for grain drying, characterized in that, It includes the following steps: S1: Biomass is crushed and put into the feeding hopper (1), and then sent into the self-driven biomass pyrolysis furnace (3) through the feeding and conveying device (2). Then, it is ignited through the ignition door (35) in sequence, and the oxygen content in the self-driven biomass pyrolysis furnace (3) is controlled by the primary air blower (32). By means of the calorific value of the biomass itself, its self-driven pyrolysis gasification is realized. The ash residue after the reaction is discharged through the mechanical ash auger (31). S2: The combustible gas generated during the biomass gasification process is introduced into the combustion chamber (41), and is fully burned by blowing air through the secondary air blower (33). After removing organic pollutants such as tar, the generated high-temperature hot flue gas is introduced into the air mixing chamber (42), and cold air is supplemented by the air distribution valves (421) / (422) on both sides of the air mixing chamber (42), so that the high-temperature hot flue gas and the cold air are fully mixed, and the temperature of the hot air after air distribution is controlled at 50~65°C. S3: The hot air after air distribution is directly introduced into the grain dryer through the air duct (5) for grain drying, and then is discharged up to standard after waste gas treatment.

2. A biomass self-driven pyrolysis heating method for grain drying according to claim 1, characterized in that, In the step S1, the temperature of the biomass pyrolysis gasification is preferably controlled at 650~800°C, and the negative pressure in the furnace is controlled at -50~-200 Pa; in the step S2, the temperature of the combustion chamber (41) is not lower than 850°C.

3. A biomass self-driven pyrolysis heat supply method for grain drying according to claim 1, characterized in that, The feeding and conveying device (2), the primary air blower (32), the secondary air blower (33), and the air distribution valve (421) all adopt frequency conversion control. Temperature monitoring probes are provided at the outlets of the self-driven biomass pyrolysis furnace (3), the combustion chamber (41), the air mixing chamber (42), and the air duct (5) of the grain dryer, and the opening degree of the air distribution valve (421) and the temperature of the air duct (5) at the outlet of the air mixing chamber (42) are automatically linked and controlled, and the feeding and conveying device (2) is linked and controlled with the temperature in the self-driven biomass pyrolysis furnace (3).

4. A biomass self-driven pyrolysis heating equipment for grain drying, adopting a biomass self-driven pyrolysis heating method for grain drying according to any one of claims 1-3, characterized in that, It mainly includes units such as a feeding hopper (1), a feeding and conveying device (2), a self-driven biomass pyrolysis furnace (3), a combustion-gas distribution integrated device (4), an air duct (5), and a control box (6), etc. The feeding hopper (1), the feeding and conveying device (2), and the self-driven biomass pyrolysis furnace (3) are connected end to end in sequence. The flue gas pipe (34) of the self-driven biomass pyrolysis furnace (3) is inserted into the combustion-gas distribution integrated device (4), and the air duct (5) is connected to the top of the combustion-gas distribution integrated device (4).

5. A biomass self-driven pyrolysis heat supply equipment for grain drying according to claim 4, characterized in that, The self-driven biomass pyrolysis furnace (3) adopts a reciprocating grate furnace structure form, and its side wall is provided with an ignition door (35).

6. The biomass self-driven pyrolysis heat supply equipment for grain drying according to claim 4, characterized in that, The combustion-gas distribution integrated device (4) includes a combustion chamber (41) and an air mixing chamber (42). A porous retaining wall (43) is used to separate the combustion chamber (41) and the air mixing chamber (42) in the middle, and the air duct (5) is connected to the top of the air mixing chamber (42).

7. The biomass self-driven pyrolysis heat supply equipment for grain drying according to claim 6, characterized in that, A slag cleaning port (411) is provided at the bottom of the combustion chamber (41).

8. A biomass self-driven pyrolysis heat supply equipment for grain drying according to claim 6, characterized in that, A plurality of air holes (44) are provided on the porous retaining wall (43). The shape of the air holes (44) is square, and the total area of the air holes (44) opened accounts for 20~40% of the area of the porous retaining wall (43).

9. A biomass self-driven pyrolysis heating equipment for grain drying according to claim 6, characterized in that, Two groups of air distribution valves (421) / (422) are symmetrically arranged on both sides of the air mixing chamber (42), and one of the groups is manually controlled.

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