Gas heat carrier internal heating type pyrolyzing furnace

Abstract

The invention discloses a gas heat carrier internal heating type pyrolyzing furnace. Belongs to the technical field of biomass pyrolysis and comprises a material distributor, a rotational flow plasma gas generation ejector, a screw vortex stirrer, a roller grate and the like. Biomass enters the furnace body through the feeding device and is evenly distributed in the furnace body through the material distributor, the drying and volatilization analysis process is completed, refined control over reaction conditions can be achieved through temperature and pressure measuring points, and the rotational flow plasma gas generator is arranged below the gas uniformizing chamber so that plasma energy loss can be reduced to the maximum extent. A screw vortex stirrer stirs the biochar to enable the biochar to be uniformly impacted by high-energy plasmas and form vortex in the center, so that pyrolysis gas quickly leaves the holes, and after activation is completed, the pyrolysis gas enters carbon cooling equipment through a roller grate arrangement and is cooled by two sections of carbon cooling bins; the system has the advantages of integration of activated carbon production and activation, low energy consumption, high energy utilization rate, high activated carbon yield, high activated carbon quality, stable system operation and low maintenance cost.

Description

Technical Field

[0001] The invention belongs to the technical field of biomass dry distillation and relates to a gas heat carrier internal heating type dry distillation furnace. Background Art

[0002] At present, a large amount of waste biomass raw materials are usually generated during the production and processing of agriculture and forestry. Traditionally, these waste woods are often directly burned or abandoned, which not only wastes resources but also has a negative impact on the environment. In recent years, with the enhancement of environmental awareness and the development of resource recycling technology, biomass pyrolysis technology has gradually received attention.

[0003] The comprehensive utilization of biomass pyrolysis is a promising way to utilize waste biomass resources. By heating biomass in a high-temperature oxygen-free or oxygen-deficient environment, it is decomposed into a variety of useful products such as charcoal and pyrolysis gas. This process not only effectively processes biomass resources, but also produces high-value-added biochar and other by-products. As the quality requirements for such products continue to increase, biochar often needs to be activated and processed into activated carbon. However, the existing activation method mainly involves sending biochar into a special activation furnace for activation. This method not only requires additional activation equipment, but also consumes a lot of energy.

[0004] On the other hand, in the face of traditional biochar activation methods, it is now proposed to use high-energy plasma gas to pyrolyze biomass to directly produce activated carbon, shortening the process and reducing costs. However, the existing biomass pyrolysis furnace is not designed for plasma pyrolysis activation process. Direct use will cause problems such as large plasma energy loss and uneven activation, which limits the promotion and use of this process. Therefore, there is an urgent need for a pyrolysis furnace that is suitable for plasma gas pyrolysis biomass process. Summary of the invention

[0005] In view of the above problems, the purpose of the present invention is to address the defects of the prior art and propose a gas heat carrier internal heating pyrolysis furnace; while retaining the advantages of the vertical pyrolysis furnace such as small footprint and suitability for continuous production, the present invention solves the problems of uneven biochar activation, excessive heavy fractions such as tar, and large plasma gas energy loss by utilizing components such as a spiral material distributor, a swirl plasma gas generator injector, and a screw vortex agitator, and designs a pyrolysis furnace that can achieve high-value utilization of waste biomass resources.

[0006] The technical solution of the present invention is: a gas heat carrier internal heating pyrolysis furnace described in the present invention includes a feed hopper, a temporary storage bin is connected to the lower end of the feed hopper, a furnace body is connected to the lower end of the temporary storage bin, a primary cooling section is connected to the lower end of the furnace body, and a secondary cooling section is connected to the lower end of the primary cooling section.

[0007] Furthermore, a pyrolysis gas channel is provided at the top of the furnace body, near the temporary storage bin, and a collecting array umbrella is connected to the lower end of the pyrolysis gas channel;

[0008] A material distributor is arranged at the lower end of the collecting array umbrella, a number of evenly distributed temperature and pressure sensors are arranged at the lower end of the material distributor and the inner wall of the furnace body, and a second plug gate with a hole is arranged at the lower end of the temperature and pressure sensor;

[0009] An opening and closing gate is arranged at the middle and lower end of the furnace body, and two groups of screw vortex agitators are arranged on the upper wall of the opening and closing gate;

[0010] A plurality of roller grates are arranged on the body wall of the furnace body and at the lower end of the opening and closing gate.

[0011] Further, the screw vortex agitator is composed of four screws arranged in a square;

[0012] The material used is nickel-based alloy and the pitch is 50-100mm.

[0013] Furthermore, a number of gas-uniform chambers are correspondingly opened on the body wall of the furnace body. The cross-section of the gas-uniform chamber is hexagonal, and a mesh-shaped gas-uniform plate is arranged inside. The gas-uniform plate is composed of a hollow heat-resistant pipe, in which a circuit for supplying energy to a swirl plasma gas generating injector is arranged. A swirl plasma gas generating injector is installed on the inner wall of the gas-uniform chamber.

[0014] Further, the swirl plasma gas generating injector comprises a conical electrode, a circular tube electrode and a swirl device connected to each other;

[0015] The material used for the conical electrode is a tungsten-rhenium alloy, and the material used for the circular tube electrode is a nickel-based alloy.

[0016] Furthermore, a gas heat carrier delivery pipe is arranged on the gas homogenizing chamber.

[0017] Furthermore, a gate is inserted between the temporary storage bin and the furnace body.

[0018] A slide gate three is inserted between the furnace body and the primary cooling section.

[0019] Furthermore, a nitrogen air outlet and a nitrogen air supply outlet are respectively provided at the upper and lower ends of the first-stage cooling section.

[0020] Furthermore, the material distributor is in the shape of a spiral tube with a semicircular cross-section. The gaps between the tubes allow the material to pass through and guide the pyrolysis gas to form a vortex. The angle between the conical busbar and the furnace wall is 50 to 60 degrees. The material is made of nickel-based alloy.

[0021] Furthermore, in the temperature and pressure sensors, the temperature sensor is an S-type thermocouple, and the pressure sensor is a capacitive sensor, and their shells are both made of high-temperature resistant and corrosion-resistant ceramic materials.

[0022] The beneficial effects of the present invention are as follows: 1. The combination of the spiral material distributor and the collection array umbrella increases the circulation rate of the gas heat carrier, thereby increasing the overall pyrolysis efficiency by 10-20%; 2. The coordinated operation of the multi-stage slide gate and the temperature and pressure sensor realizes the automatic and stable operation of the system, while ensuring the stable quality of the activated carbon; 3. The design of the downward-opening swirl plasma gas generating injector does not require additional plasma generating equipment, thereby minimizing the energy loss of the plasma gas; 4. The use of high-energy plasma gas heat carrier pyrolysis decomposes wood tar into charcoal and light fractions, and reduces the generation of heavy fractions by more than 90%, thereby enhancing the stability of the system operation, increasing the charcoal yield, and realizing the integrated production and activation of activated carbon. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of the present invention;

[0024] In the figure, 1 is a feed hopper, 2 is a temporary storage bin, 3 is a gate gate 1, 4 is a collecting array umbrella, 5 is a pyrolysis gas channel, 6 is a material distributor, 7 is a temperature and pressure sensor, 8 is a gate gate 2, 9 is an air-homogenizing chamber, 10 is a gas heat carrier conveying pipe, 11 is an air-homogenizing plate, 12 is a screw, 13 is an opening and closing gate, 14 is a roller grate, 15 is a gate gate 3, 16 is a primary cooling section, 17 is a nitrogen air outlet, 18 is a nitrogen air supply outlet, 19 is a secondary cooling section, 20 is a conical electrode, 21 is a circular tube electrode, and 22 is a cyclone. DETAILED DESCRIPTION

[0025] The specific technical scheme of the present invention is further described in detail below with reference to specific examples.

[0026] As shown in the figure, a gas heat carrier internal heat type pyrolysis furnace according to the present invention includes a furnace body, which includes basic equipment such as a spiral material distributor (material distributor), a swirl plasma gas generator injector, a screw vortex agitator and a roller grate;

[0027] The furnace body is divided into a pre-carbonization section, a carbonization section and an activation section according to the reaction process; the biomass enters the furnace body through the feeding device (feeding hopper 1, temporary storage bin 2), and is evenly distributed in the furnace body through the spiral material distributor (material distributor 6) at the top of the pre-carbonization section to complete the drying and volatilization analysis process and help form a vortex in the furnace body;

[0028] Temperature and pressure measuring points (temperature and pressure sensors 7) are arranged on the furnace wall of the carbonization section to achieve fine control of reaction conditions;

[0029] The activation section furnace wall is provided with a uniform gas chamber 9, and a cyclonic plasma gas generator injector is provided below the uniform gas chamber 9 to minimize the plasma energy loss, and decompose the heavy fractions such as tar in the biochar into charcoal and pyrolysis gas through high-energy particle collision, thus realizing the integrated production and activation of activated carbon;

[0030] In the activation section, a screw vortex agitator is installed on the opening and closing gate plate and arranged in a square shape. The screw vortex agitator stirs the biochar so that it is evenly impacted by the high-energy plasma and forms a vortex in the center, so that the pyrolysis gas quickly leaves the hole, making the activation reaction more sufficient and uniform. The light fraction produced by the decomposition and the gas heat carrier that loses energy enter the carbonization section upward to distill the wood. The distillation gas and gas heat carrier produced by the distillation upward dry and pre-carbonize the biomass entering the pretreatment section, and then are collected and sent out by the distillation gas collection and transportation system. After the activation is completed, it passes through the roller grate 14 and enters the charcoal cooling equipment to complete the cooling by the two-section cold charcoal bin. The upper cooling bin is connected to the nitrogen circulation fan, and the lower cooling bin is cooled by circulating natural wind, and finally it is taken out of the furnace for packaging.

[0031] Furthermore, the feeding device is composed of a feeding hopper 1 and a temporary storage bin 2. An electrically controllable plug gate 3 is installed between the feeding hopper 1, the temporary storage bin 2 and the furnace body. The crushed material first enters the temporary storage bin 2 arranged between the feeding hopper 1 and the furnace body, and the plug gate 3 is opened and closed according to the pyrolysis conditions obtained by the sensor to realize continuous batch feeding.

[0032] Furthermore, a collecting array umbrella 4 and a pyrolysis gas channel 5 are installed on the top of the furnace body; a material distributor 6 is provided below the collecting array umbrella 4, the central axis of the material distributor 6 is aligned with the central axis of the collecting array umbrella 4, and the top of the material distributor 6 is at the same height as the bottom of the collecting array umbrella 4.

[0033] Furthermore, in the present invention, high-energy plasma pyrolysis gas is used as a circulating heat carrier (gas heat carrier), and the gas heat carrier is a purified full-fraction pyrolysis gas, the main components of which are methane, carbon monoxide, hydrogen and nitrogen.

[0034] Furthermore, the high-energy plasma pyrolysis gas mainly contains hydrogen radicals, methyl radicals, carbonyl radicals and electrons, the temperature is 350-450°C, the pressure is 0.15-0.2MPa, and the ion collision frequency is 10 7 -10 8 s -1 .

[0035] Furthermore, below the material distributor 6 is the carbonization section, and the furnace wall of the carbonization section is provided with temperature and pressure sensors 7, wherein the temperature sensor is an S-type thermocouple, and the temperature measurement range is 100-800°C, and the pressure sensor is a capacitive sensor, and the pressure measurement range is 0.05-0.3MPa, and the housings thereof are made of high temperature resistant and corrosion resistant ceramic materials;

[0036] A plug gate 8 with holes is provided at the bottom of the carbonization section, through which the gas heat carrier can pass and realize batch activation.

[0037] Furthermore, the spiral material distributor (material distributor 6) is shaped like a spiral tube with a semicircular cross-section. The gaps between the tubes allow materials to pass through. The spiral conical design helps to collect pyrolysis gas, increase the circulation rate of the gas heat carrier, and guide the pyrolysis gas to form a vortex. The angle between the conical busbar and the furnace wall is 50 to 60 degrees, and the material is made of nickel-based alloy.

[0038] Furthermore, an aeration chamber 9 is provided on the furnace wall of the activation section. The cross-section of the aeration chamber 9 is hexagonal. The outside of the aeration chamber 9 is connected to the gas heat carrier delivery pipe 10, and a mesh rectifier plate (aeration plate 11) is provided inside. The rectifier plate is composed of a heat-resistant pipeline, in which a line for supplying energy to a swirl plasma gas generator injector is arranged. A swirl plasma gas generator injector is provided on the inner wall of an adjacent aeration chamber 9, and a downward nozzle is used to effectively prevent solid powder from entering the pipe.

[0039] Furthermore, the swirl plasma gas generator is composed of a conical electrode 20, a circular tube electrode 21 and a cyclone 22, wherein the conical electrode 20 is made of a tungsten-rhenium alloy, and the circular tube electrode 21 is made of a nickel-based alloy. The gas heat carrier generates a vortex through the cyclone 22, and is ionized between the circular tube electrode 21 and the conical electrode 20 to generate a high-energy plasma gas heat carrier, and then is directly sprayed into the activation section of the furnace body.

[0040] After activation is completed, the opening and closing gate 13 is opened, and the activated carbon passes through the roller grate 14 to remove the scum while arranging the charcoal in an orderly manner to facilitate subsequent heat dissipation.

[0041] Furthermore, the activation section is from the bottom of the carbonization section to the opening and closing gate 13. The screw vortex agitator is composed of four screws 12 (four rotating in the same direction) arranged in a square in the activation section. The material can be moved longitudinally and radially by rotation. The activated carbon activated by the furnace wall is brought to the center of the furnace body by rotating in the same direction, which is conducive to the separation of light distillates in the gaps of the activated carbon. At the same time, the rotation directions are all the same. The four screws 12 generate a small-scale spiral rising vortex in the center, which makes the circulation rate of the gas heat carrier in the furnace higher. The material is preferably a nickel-based alloy, the pitch is preferably 50-100mm, and the ratio of the outer diameter of the thread to the reactor diameter is preferably 1:4-1:3 to prevent the formation of a dead zone;

[0042] The screw 12 is designed to have a pitch slightly larger than the material size and a large thread diameter, and its main function is to enable the biochar to be fully activated by the plasma.

[0043] Furthermore, a roller grate 14 is provided at the bottom of the furnace body. The roller grate 14 arranges the charcoal neatly by rolling, which is helpful for subsequent heat dissipation and reduces the breakage of the activated carbon.

[0044] Furthermore, a charcoal cooling system is provided below the furnace body, and a gate 3 15 is provided between the outlet at the lower end of the furnace body and the upper end of the charcoal cooling system;

[0045] The charcoal cooling system is divided into a primary cooling section 16 and a secondary cooling section 19. A gate is provided between the primary cooling section 16 and the secondary cooling section 19. A nitrogen outlet 17 is provided at the top of the side wall of the primary cooling section 16, and a nitrogen air supply port 18 is provided at the bottom.

[0046] After the charcoal is cooled in the primary cooling section 16, it enters the secondary cooling section 19 for natural cooling. After the cooling is completed, it can be directly packaged after it is taken out of the furnace.

[0047] The entire system is automatically controlled during operation. After setting the time and reaction conditions, the central control system controls the gate to feed materials in batches, and the materials are distributed in layers in the furnace.

Claims

1. A gas heat carrier internal heating pyrolysis furnace, characterized in that: The invention comprises a feed hopper (1), a temporary storage bin (2) connected to the lower end of the feed hopper (1), a furnace body connected to the lower end of the temporary storage bin (2), a primary cooling section (16) connected to the lower end of the furnace body, and a secondary cooling section (19) connected to the lower end of the primary cooling section (16).

2. A gas heat carrier internal heating pyrolysis furnace according to claim 1, characterized in that: A pyrolysis gas channel (5) is provided at the top of the furnace body, near the temporary storage bin (2), and a collecting array umbrella (4) is connected to the lower end of the pyrolysis gas channel (5); A material distributor (6) is arranged at the lower end of the collecting array umbrella (4), a plurality of evenly distributed temperature and pressure sensors (7) are arranged at the lower end of the material distributor (6) and the inner wall of the furnace body, and a second plug gate (8) with a hole is arranged at the lower end of the temperature and pressure sensor (7); An opening and closing gate plate (13) is arranged at the middle and lower end of the furnace body, and two groups of screw vortex agitators are arranged on the upper wall of the opening and closing gate plate (13); A plurality of roller grates (14) are arranged on the wall of the furnace body and at the lower end of the opening and closing gate plate (13).

3. A gas heat carrier internal heating type pyrolysis furnace according to claim 2, characterized in that: The screw vortex agitator is composed of four screws (12) arranged in a square shape; the material used is a nickel-based alloy, and the pitch is 50-100 mm.

4. The gas heat carrier internal heating pyrolysis furnace according to claim 1, characterized in that: A plurality of uniform gas chambers (9) are correspondingly opened on the body wall of the furnace body. The cross section of the uniform gas chamber (9) is hexagonal and contains a mesh-shaped uniform gas plate (11). The uniform gas plate (11) is composed of a hollow heat-resistant pipe in which a circuit for supplying energy to a swirl plasma gas generator injector is arranged. The swirl plasma gas generator injector is installed on the inner wall of the uniform gas chamber (9).

5. A gas heat carrier internal heating type pyrolysis furnace according to claim 4, characterized in that: The swirl plasma gas generating injector comprises a conical electrode (20), a circular tube electrode (21) and a cyclone (22) which are connected to each other; The material used for the conical electrode (20) is a tungsten-rhenium alloy, and the material used for the circular tube electrode (21) is a nickel-based alloy.

6. A gas heat carrier internal heating type pyrolysis furnace according to claim 4, characterized in that: A gas heat carrier conveying pipe (10) is also arranged on the gas homogenizing chamber (9).

7. The gas heat carrier internal heating pyrolysis furnace according to claim 1, characterized in that: A gate (3) is inserted between the temporary storage bin (2) and the furnace body. A third slide gate (15) is inserted between the furnace body and the primary cooling section (16).

8. The gas heat carrier internal heating pyrolysis furnace according to claim 1, characterized in that: A nitrogen air outlet (17) and a nitrogen air supply outlet (18) are respectively provided at the upper and lower ends of the primary cooling section (16).

9. The gas heat carrier internal heating type retort furnace according to claim 2, characterized in that: The material distributor (6) is in the shape of a spiral tube with a semicircular cross section. The gap between the tubes allows the material to pass through and guides the pyrolysis gas to form a vortex. The angle between the conical generatrix and the furnace wall is 50-60 degrees. The material is made of nickel-based alloy.

10. The gas heat carrier internal heating type retort furnace according to claim 2, characterized in that: In the temperature and pressure sensor (7), the temperature sensor is an S-type thermocouple, and the pressure sensor is a capacitive sensor, and their shells are both made of high-temperature resistant and corrosion-resistant ceramic materials.

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