Biomass pyrolysis carbonization system capable of utilizing waste heat of ash of combustion furnace

Abstract

The invention discloses a biomass pyrolysis and carbonization system utilizing combustion furnace ash waste heat, the biomass pyrolysis and carbonization system comprises a combustion furnace and a pyrolysis and carbonization furnace, the pyrolysis and carbonization furnace comprises a cylindrical furnace wall, a pyrolysis pipeline is coaxially and rotatably mounted in the furnace wall, a pyrolysis cavity is formed in the pyrolysis pipeline, and the pyrolysis cavity is communicated with the combustion furnace. A gap between the pyrolysis pipeline and the inner wall of the furnace wall forms an ash cavity; an inner conveying screw is fixed on the inner wall of the pyrolysis pipeline, and an outer conveying screw is fixed on the outer wall of the pyrolysis pipeline; the rotation direction of the inner conveying screw is opposite to that of the outer conveying screw, when the pyrolysis pipeline rotates, ash in the ash cavity is conveyed from front to back, and biomass in the pyrolysis cavity is conveyed from back to front. According to the invention, the boiler combustion ash is used as a heat source for pyrolysis and carbonization, so that the pyrolysis of biomass is realized, and the waste heat of the ash is fully utilized; and the generated pyrolysis gas has a combustion-supporting effect on the combustion furnace, and the problem that the pyrolysis gas cannot be directly discharged is solved.

Description

Technical Field

[0001] The invention relates to a biomass pyrolysis and carbonization system utilizing the residual heat of combustion furnace ash, and belongs to the technical field of biomass pyrolysis and carbonization. Background Art

[0002] As my country's energy and environmental problems become increasingly severe, the energy structure has undergone a major transformation. Clean energy represented by biomass has received more and more attention from the country and society. In particular, new energy represented by biomass energy is the focus of my country's future energy development. Biomass pyrolysis carbonization is a thermochemical process that heats and decomposes biomass raw materials under anaerobic or low-oxygen conditions to convert them into solid (biochar), liquid (bio-oil) and gaseous (combustible gas) products. Pyrolysis carbonization can not only provide clean energy and improve the energy structure, but also fix carbon and realize carbon reuse, so it has great application potential.

[0003] In the prior art, the pyrolysis carbonization device of biomass is generally heated by electricity, which consumes a lot of energy. Moreover, during the heating and carbonization, the biomass is heated unevenly, resulting in low carbonization efficiency, the generated pyrolysis gas does not meet the emission standards, and the waste gas treatment cost is also high; and in the use of the combustion boiler, a large amount of ash is generated, and the temperature of the ash is usually between 400 and 600 degrees Celsius. The traditional treatment method is to use water-cooled slag technology, and the ash is continuously discharged and cooled through the slag removal equipment under the slag discharge part of the liquid slag discharge boiler. However, after this water quenching process, the high-temperature waste heat of the ash is converted into low-temperature waste heat of the slag flushing water, resulting in the high-quality waste heat in the ash not being effectively utilized, and the recovery rate of the waste heat of the slag flushing water is relatively low, resulting in a large amount of waste heat waste.

[0004] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0005] In view of the deficiencies in the background technology, the present invention provides a biomass pyrolysis carbonization system that utilizes the waste heat of combustion furnace ash. The ash from boiler combustion is used as the heat source for pyrolysis carbonization to achieve pyrolysis of biomass and make full use of the waste heat of ash. The generated pyrolysis gas plays a role in supporting combustion in the combustion furnace and solves the problem that the pyrolysis gas cannot be directly discharged.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions: A biomass pyrolysis carbonization system utilizing the waste heat of ash from a combustion furnace comprises a combustion furnace and a pyrolysis carbonization furnace, wherein the pyrolysis carbonization furnace comprises a cylindrical furnace wall, a pyrolysis pipe is coaxially mounted in the furnace wall, a pyrolysis chamber is formed inside the pyrolysis pipe, and an ash chamber is formed in the gap between the pyrolysis pipe and the inner wall of the furnace wall; An inner conveying screw is fixed on the inner wall of the pyrolysis pipe, and an outer conveying screw is fixed on the outer wall of the pyrolysis pipe; the inner conveying screw and the outer conveying screw have opposite rotation directions, and when the pyrolysis pipe rotates, the ash in the ash chamber is conveyed from front to back, while the biomass in the pyrolysis chamber is conveyed from back to front, and the ash inlet is connected to the ash outlet of the combustion furnace.

[0007] Furthermore, both ends of the furnace wall are rotatably connected to the pyrolysis pipe through bearings, and a transmission gear and a rotary motor are fixedly mounted on the rear end of the pyrolysis pipe. The rotary motor drives the transmission gear to rotate through gear transmission, thereby driving the pyrolysis pipe to rotate.

[0008] Furthermore, the front end of the pyrolysis pipe extends out of the front end of the furnace wall, and a front sealing cabin is provided at the front end of the pyrolysis pipe. The pyrolysis chamber and the front sealing cabin are sealed by a graphite packing.

[0009] Furthermore, the lower end of the sealed cabin is connected to a charcoal buffer hopper, and a charcoal outlet screw is provided at the lower outlet of the charcoal buffer hopper, and the charcoal outlet screw is driven by a charcoal outlet motor.

[0010] Furthermore, a pyrolysis gas pipeline is provided on the top of the sealed cabin, one end of the pyrolysis gas pipeline is connected to the front sealed cabin, and the other end is connected to the inner cavity of the combustion furnace.

[0011] Furthermore, a feed conveyor belt is provided at the feed inlet of the combustion furnace, and a chain conveyor belt is provided inside the combustion furnace.

[0012] Furthermore, the furnace wall is provided with an ash discharge port at the rear end of the ash chamber, an ash box is provided below the ash discharge port, and a temperature sensor is provided at the position of the furnace wall at the ash discharge port.

[0013] Furthermore, the rear end of the pyrolysis pipeline extends out of the rear end of the furnace wall, and a rear sealing cabin is provided at the rear end of the pyrolysis pipeline. The pyrolysis chamber and the rear sealing cabin are also sealed by a graphite packing.

[0014] Furthermore, a feed screw and a feed motor driving the feed screw are connected to the rear end of the rear sealed cabin, the feed screw passes through the feed screw and extends into the pyrolysis chamber, and the feed screw outlet extends into the pyrolysis chamber.

[0015] After adopting the above technical solution, the present invention has the following advantages compared with the prior art: 1. The pyrolysis carbonization furnace is a double-layer design, with the outer side being the furnace wall, a pyrolysis pipe being arranged inside the furnace wall, the inside of the pyrolysis pipe being the pyrolysis chamber, and the outside being the ash chamber. The biomass is on the inner side of the pyrolysis pipe, and the heat of the high-temperature ash is transferred to the biomass inside through the pyrolysis pipe, thereby realizing pyrolysis of the biomass, making full use of the waste heat of the ash, and realizing heat recovery.

[0016] 2. An inner conveying screw is fixed on the inner wall of the pyrolysis pipeline, and an outer conveying screw is fixed on the outer wall of the pyrolysis pipeline; the inner conveying screw and the outer conveying screw have opposite rotation directions, which simplifies the heat transfer and conveying structure, improves the conveying efficiency, and can realize continuous production; 3. One end of the pyrolysis gas pipeline is connected to the front sealed cabin, and the other end is connected to the inner cavity of the combustion furnace. The pyrolysis gas generated by the pyrolysis carbonization furnace during the pyrolysis carbonization process can be transported to the combustion furnace through the pyrolysis gas pipeline, and ignited and burned in the combustion furnace, thereby providing an additional energy source for the combustion furnace, playing a role in assisting the combustion of the combustion furnace, and burning the pyrolysis gas at the same time, solving the problem that the pyrolysis gas cannot be directly discharged.

[0017] 4. A temperature sensor is installed on the furnace wall at the ash discharge port. When the temperature sensor detects that the discharged ash temperature is high, the rotation speed of the rotary motor can be reduced, the heat exchange time can be increased, and the residual heat of the ash can be fully utilized.

[0018] The present invention is described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the overall system in the present invention; Figure 2 is a partial cross-sectional view of the present invention; Figure 3 It is a schematic diagram of the internal structure of the pyrolysis carbonization furnace in the present invention.

[0020] In the figure, 1-combustion furnace, 2-chain conveyor belt, 3-pyrolysis carbonization furnace, 31-pyrolysis gas pipeline, 32-front sealed cabin, 33-pyrolysis pipeline, 34-ash inlet, 35-pyrolysis chamber, 36-external conveying screw, 37-ash chamber, 38-inner conveying screw, 39-ash outlet, 310-transmission gear, 311-rear sealed cabin, 312-feeding screw, 313-rotating motor, 314-feeding hopper, 315-feeding motor, 316-charcoal outlet screw, 317-charcoal buffer hopper, 318-charcoal outlet motor, 319-furnace wall, 320-temperature sensor, 321-bearing, 4-ash box, 5-charcoal collecting box, 6-feeding conveyor belt. DETAILED DESCRIPTION

[0021] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0022] like Figure 1-3As shown, the present invention provides a biomass pyrolysis carbonization system for utilizing the waste heat of ash from a combustion furnace, comprising a combustion furnace 1 and a pyrolysis carbonization furnace 3, wherein the pyrolysis carbonization furnace 3 comprises a cylindrical furnace wall 319, wherein a pyrolysis pipe 33 is coaxially rotatably installed in the furnace wall 319, wherein a pyrolysis chamber 35 is formed inside the pyrolysis pipe 33, and an ash chamber 37 is formed in the gap between the pyrolysis pipe 33 and the inner wall of the furnace wall 319; An inner conveying screw 38 is fixed on the inner wall of the pyrolysis pipe 33, and an outer conveying screw 36 is fixed on the outer wall of the pyrolysis pipe 33; the inner conveying screw 38 and the outer conveying screw 36 have opposite rotation directions. When the pyrolysis pipe 33 rotates, the ash in the ash chamber 37 is conveyed from front to back, and the biomass in the pyrolysis chamber 35 is conveyed from back to front. The ash inlet 34 is connected to the ash outlet of the combustion furnace 1.

[0023] The two ends of the furnace wall 319 are rotatably connected to the pyrolysis pipe 33 through bearings 321. The rear end of the pyrolysis pipe 33 is fixedly sleeved with a transmission gear 310 and a rotary motor 313. The rotary motor 313 drives the transmission gear 310 to rotate through gear transmission, thereby driving the pyrolysis pipe 33 to rotate. The pyrolysis carbonization furnace body 3 adopts a rotary method to transport materials, and opposite conveying screws are arranged inside and outside the pyrolysis pipe 33. When the pyrolysis pipe 33 rotates, it can simultaneously drive the opposite conveying of biomass materials and ash by rotary means, which simplifies the heat transfer and conveying structure, improves the conveying efficiency, and can realize continuous production.

[0024] The ash outlet in the combustion furnace 1 is discharged to the front end of the ash chamber 37 of the pyrolysis carbonization furnace 3. The rotary motor 313 drives the pyrolysis pipe 33 to rotate. The high-temperature ash is on the outside of the pyrolysis pipe 33, and the biomass is on the inside of the pyrolysis pipe 33. The heat of the high-temperature ash is transferred to the biomass inside the pyrolysis pipe 33 through the pyrolysis pipe 33, realizing pyrolysis of the biomass, making full use of the waste heat of the ash, and realizing heat recovery.

[0025] The front end of the pyrolysis pipe 33 extends out of the front end of the furnace wall 319. The front end of the pyrolysis pipe 33 is provided with a front sealed cabin 32. The pyrolysis chamber 35 and the front sealed cabin 32 are sealed by a graphite packing. A pyrolysis gas pipe 31 is provided on the top of the sealed cabin 32. One end of the pyrolysis gas pipe 31 is connected to the front sealed cabin 32, and the other end is connected to the inner cavity of the combustion furnace 1. The pyrolysis gas generated by the pyrolysis carbonization furnace 3 during the pyrolysis carbonization process can be transported to the combustion furnace 1 through the pyrolysis gas pipe 31, and ignited and burned in the combustion furnace 1, thereby providing an additional energy source for the combustion furnace, playing a role in combustion-supporting the combustion furnace, and burning the pyrolysis gas at the same time, solving the problem that the pyrolysis gas cannot be directly discharged.

[0026] The lower end of the sealed cabin 32 is connected to a charcoal buffer hopper 317, and a charcoal outlet screw 316 is provided at the lower outlet of the charcoal buffer hopper 317, and the charcoal outlet screw 316 is driven by a charcoal outlet motor 318; the charcoal after pyrolysis carbonization can be cached in the charcoal buffer hopper 317, and at the same time it plays a certain sealing role to prevent the pyrolysis gas from overflowing through the charcoal outlet, and finally discharged by the charcoal outlet screw 316 and finally collected in the charcoal collecting box 5.

[0027] The inlet of the combustion furnace 1 is provided with a feed conveyor belt 6, and the combustion furnace 1 is provided with a chain conveyor belt 2. The burning material will pass through the feed conveyor belt 6 and enter the combustion furnace 1, and after being ignited, it will start to burn and provide heat, and then be transported to the rear end of the combustion furnace by the high-temperature resistant chain conveyor belt 2, during which time it will be fully burned to form ash, and finally sent to the ash inlet 34 by the high-temperature resistant chain conveyor belt 2. During this period, the combustion raw materials are continuously fed into the combustion furnace 1, and ash will also be continuously generated and fed into the ash inlet 34.

[0028] The furnace wall 319 is provided with an ash discharge port 39 at the rear end of the ash chamber 37, an ash box 4 is provided below the ash discharge port 39, and a temperature sensor 320 is provided at the furnace wall 319 at the position of the ash discharge port 39. When the temperature sensor 320 detects that the temperature of the discharged ash is high, the speed of the rotary motor 313 can be reduced, the heat exchange time can be increased, and the residual heat of the ash can be fully utilized.

[0029] The rear end of the pyrolysis pipeline 33 extends beyond the rear end of the furnace wall 319. The rear end of the pyrolysis pipeline 33 is provided with a rear sealed cabin 311. The pyrolysis chamber 35 and the rear sealed cabin 311 are also sealed by graphite packing. The front sealed cabin 32 and the rear sealed cabin 311 together seal the middle pyrolysis chamber 35. The rear end of the rear sealed cabin 311 is connected to a feed screw 312 and a feed motor 315 driving the feed screw 312. The feed screw 312 passes through the feed screw 312 and extends into the pyrolysis chamber 35. The outlet of the feed screw 312 extends into the pyrolysis chamber 35. The biomass raw materials to be pyrolyzed enter the feed screw 312 through the feed hopper 314, are transported to the pyrolysis chamber 35 by the feed screw 312, and are transported to the rear end in the pyrolysis chamber 35 under the drive of the inner transport screw 38.

[0030] The specific working principle of the present invention: The pyrolysis carbonization system comprises a combustion furnace 1 and a pyrolysis carbonization furnace 3. The ash inlet 34 of the pyrolysis carbonization furnace 3 is connected to the ash outlet of the combustion furnace 1. The pyrolysis carbonization furnace 3 is a double-layer design, with a furnace wall 319 on the outside. A pyrolysis pipe 33 is arranged inside the furnace wall 319. The inside of the pyrolysis pipe 33 is a pyrolysis chamber 35, and the outside is an ash chamber 37. An inner conveying screw 38 is fixed to the inner wall of the pyrolysis pipe 33, and an outer conveying screw 36 is fixed to the outer wall of the pyrolysis pipe 33. The inner conveying screw 38 rotates in the opposite direction to the outer conveying screw 36. When the pyrolysis pipe 33 rotates, the ash in the ash chamber 37 is transported from front to back, and the biomass in the pyrolysis chamber 35 is transported from back to front. This system uses boiler combustion ash as the heat source for pyrolysis carbonization. The pyrolysis carbonization furnace 3 is a double-layer carbonization furnace body. The outer layer is the ash chamber 37, which exchanges heat inward, and the inner layer is the pyrolysis chamber 35, which is directly separated from the ash by only one layer of pyrolysis pipe 33, and has a higher heat exchange efficiency.

[0031] The above is an example of the best implementation of the present invention, and the parts not described in detail are common knowledge of ordinary technicians in the field. The protection scope of the present invention shall be based on the content of the claims, and any equivalent transformation based on the technical enlightenment of the present invention is also within the protection scope of the present invention.

Claims

1. A biomass pyrolysis carbonization system utilizing waste heat from combustion furnace ash, characterized in that: The invention comprises a combustion furnace (1) and a pyrolysis carbonization furnace (3), wherein the pyrolysis carbonization furnace (3) comprises a cylindrical furnace wall (319), a pyrolysis pipe (33) is coaxially rotatably installed in the furnace wall (319), a pyrolysis chamber (35) is formed inside the pyrolysis pipe (33), and a slag chamber (37) is formed in the gap between the pyrolysis pipe (33) and the inner wall of the furnace wall (319); An inner conveying screw (38) is fixed on the inner wall of the pyrolysis pipe (33), and an outer conveying screw (36) is fixed on the outer wall of the pyrolysis pipe (33); the inner conveying screw (38) and the outer conveying screw (36) rotate in opposite directions, and when the pyrolysis pipe (33) rotates, the ash in the ash chamber (37) is conveyed from front to back, while the biomass in the pyrolysis chamber (35) is conveyed from back to front; the ash inlet (34) is connected to the ash outlet of the combustion furnace (1).

2. A biomass pyrolysis carbonization system for utilizing waste heat from combustion furnace ash as claimed in claim 1, characterized in that: The two ends of the furnace wall (319) are rotatably connected to the pyrolysis pipe (33) via bearings (321); a transmission gear (310) and a rotary motor (313) are fixedly mounted on the rear end of the pyrolysis pipe (33); the rotary motor (313) drives the transmission gear (310) to rotate via gear transmission, thereby driving the pyrolysis pipe (33) to rotate.

3. The biomass pyrolysis carbonization system for utilizing the waste heat of combustion furnace ash as claimed in claim 1, characterized in that: The front end of the pyrolysis pipeline (33) extends beyond the front end of the furnace wall (319), and a front sealing cabin (32) is provided at the front end of the pyrolysis pipeline (33). The pyrolysis chamber (35) and the front sealing cabin (32) are sealed by a graphite packing.

4. A biomass pyrolysis carbonization system for utilizing waste heat from combustion furnace ash as claimed in claim 3, characterized in that: The lower end of the sealed cabin (32) is connected to a charcoal buffer hopper (317), and a charcoal outlet screw (316) is provided at the lower outlet of the charcoal buffer hopper (317), and the charcoal outlet screw (316) is driven by a charcoal outlet motor (318).

5. The biomass pyrolysis carbonization system for utilizing the waste heat of combustion furnace ash as claimed in claim 3, characterized in that: A pyrolysis gas pipeline (31) is provided on the top of the sealed cabin (32), one end of the pyrolysis gas pipeline (31) is connected to the front sealed cabin (32), and the other end is connected to the inner cavity of the combustion furnace (1).

6. The biomass pyrolysis carbonization system for utilizing the waste heat of combustion furnace ash as claimed in claim 1, characterized in that: The inlet of the combustion furnace (1) is provided with a feeding conveyor belt (6), and a chain conveyor belt (2) is provided inside the combustion furnace (1).

7. The biomass pyrolysis carbonization system for utilizing the waste heat of combustion furnace ash as claimed in claim 1, characterized in that: The furnace wall (319) is provided with an ash discharge port (39) at the rear end of the ash chamber (37), an ash box (4) is provided below the ash discharge port (39), and a temperature sensor (320) is provided at the position of the furnace wall (319) at the ash discharge port (39).

8. The biomass pyrolysis carbonization system for utilizing waste heat from combustion furnace ash as claimed in claim 1, characterized in that: The rear end of the pyrolysis pipe (33) extends beyond the rear end of the furnace wall (319), and a rear sealing cabin (311) is provided at the rear end of the pyrolysis pipe (33). The pyrolysis chamber (35) and the rear sealing cabin (311) are also sealed by a graphite packing.

9. A biomass pyrolysis carbonization system for utilizing waste heat from combustion furnace ash as claimed in claim 8, characterized in that: A feeding screw (312) and a feeding motor (315) for driving the feeding screw (312) are connected to the rear end of the rear sealed cabin (311); the feeding screw (312) passes through the feeding screw (312) and extends into the pyrolysis chamber (35); and the outlet of the feeding screw (312) extends into the pyrolysis chamber (35).

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