Biomass dual-mode heating pyrolysis reaction kettle and oil gas condensation and collection device

Abstract

The invention provides a biomass dual-mode heating pyrolysis reaction kettle and an oil gas condensation and collection device, the device is provided with two working modes, including a direct heating mode and an indirect heating mode; in the direct heating mode, the heat carrier heating reaction kettle is used for heating a solid heat carrier, and a solid raw material is added into the raw material pyrolysis reaction kettle; a heat carrier in the heat carrier heating reaction kettle is heated to a set final temperature and then is conveyed into the raw material pyrolysis reaction kettle by the heat carrier conveying screw; under an anaerobic condition, the solid heat carrier is used as a heating heat source for heating a solid raw material and is uniformly stirred in the raw material pyrolysis reaction kettle to generate a pyrolysis reaction; in the indirect heating mode, the heat carrier heating reaction kettle and the raw material pyrolysis reaction kettle are both used for heating solid raw materials to perform pyrolysis reaction, and the two reaction kettles alternately perform reaction; in the two modes, pyrolysis oil gas generated by pyrolysis reaction is discharged through a pyrolysis oil gas product outlet of the reaction kettle, and after the pyrolysis oil gas passes through the multi-stage condenser, non-condensable pyrolysis gas is collected in the air bag.

Description

Technical Field

[0001] This invention belongs to the technical field of biomass pyrolysis equipment, specifically relating to a biomass dual-mode heating pyrolysis reactor and an integrated oil and gas condensation and collection device. Background Technology

[0002] As the only carbon-containing renewable energy source, biomass has advantages such as abundant reserves, zero CO2 emissions, and green renewability. At the same time, it is also the only renewable energy source that can be converted into liquid fuels and is well compatible with the use of traditional fossil fuels. Therefore, it plays an important role in the energy transition process.

[0003] With the rapid development of my country's economy and urbanization, the amount of biomass resources, such as agricultural and forestry waste, urban domestic waste, and industrial organic solid waste, has increased dramatically. It is estimated that by 2060, this amount will reach 1 billion tons of standard coal equivalent. If fully utilized, this could reduce CO2 emissions by more than 2 billion tons in 2060 alone. The efficient and high-value utilization of biomass is not only crucial for the green and sustainable development of the national economy, but also plays a significant role in achieving my country's carbon neutrality goal, meeting the major needs of my country's sustainable energy development.

[0004] Biomass pyrolysis, the conversion of low-grade biomass feedstock into gaseous fuels, liquid oils, and solid biochar under an oxygen-free environment, represents a crucial direction for the development of biomass energy. Currently, biomass pyrolysis heating methods are mainly divided into two types: direct heating with a heat carrier and indirect heating. Each method has its advantages and disadvantages. Direct heating with a heat carrier offers advantages such as high heat transfer efficiency, complete pyrolysis reaction, and less reactor coking. However, direct contact between the heat carrier and the feedstock can interfere with product analysis and reaction mechanism research. Indirect heating produces pure feedstocks and products, facilitating reaction mechanism research and product analysis. However, indirect heating suffers from disadvantages such as reactor coking and incomplete reaction. Furthermore, the collection and metering of biomass pyrolysis products present challenges in achieving precise metering. Summary of the Invention

[0005] The technical problem solved by this invention is to address the advantages and disadvantages of the two heating methods for biomass pyrolysis and the problem of inaccurate collection and measurement of biomass pyrolysis products. This invention proposes a biomass dual-mode heating pyrolysis reactor and an integrated oil and gas condensation and collection device.

[0006] The solution of the present invention is: a biomass dual-mode heating pyrolysis reactor and oil and gas condensation and collection device, including a heat carrier heating reactor, a heat carrier conveying screw, a raw material pyrolysis reactor, a pyrolysis residue tray, an insulated heat tracing pipe, a gas exhaust fan, a condenser, a gas flow meter, and a gas bag; the device is equipped with two working modes, including a direct heating mode and an indirect heating mode;

[0007] In direct heating mode: the heat carrier heating reactor is used to heat the solid heat carrier, and the solid raw material is added to the raw material pyrolysis reactor; after the heat carrier in the heat carrier heating reactor is heated to the set endpoint temperature, it is transported to the raw material pyrolysis reactor by the heat carrier conveying screw. Under oxygen-free conditions, the solid heat carrier is used as a heat source to heat the solid raw material and is stirred evenly in the raw material pyrolysis reactor to carry out the pyrolysis reaction.

[0008] In the indirect heating mode: both the heat carrier heating reactor and the raw material pyrolysis reactor are used to heat the solid raw material for pyrolysis reaction, and the two reactors react alternately;

[0009] In both modes, the cracked oil and gas generated by the pyrolysis reaction are discharged through the pyrolysis oil and gas product outlet of the reactor. After passing through a multi-stage condenser, the non-condensable pyrolysis gas is collected in a gas bag.

[0010] Preferably, the condenser includes a first-stage condenser, a second-stage condenser, a third-stage condenser, and a fourth-stage condenser connected in series; all condensers are shell-and-tube heat exchangers, and each condenser is equipped with a cooling medium and an oil collection tank. The cooling medium for the first-stage and second-stage condensers is heat transfer oil, and the cooling medium for the third-stage and fourth-stage condensers is cooling water. The tube dimensions of the first-stage and second-stage condensers are set to be larger than those of the third-stage and fourth-stage condensers.

[0011] Preferably, the pyrolysis gas outlet temperature of the first-stage condenser is maintained above 350°C, the pyrolysis gas outlet temperature of the second-stage condenser is 200–250°C, and the pyrolysis gas outlet temperature ranges of the third-stage and fourth-stage condensers are 100–150°C and 10–20°C, respectively.

[0012] Preferably, the stirring functions of both the heat carrier heating reactor and the raw material pyrolysis reactor are realized by a stirring mechanism, which includes a stirring motor, a stirring shaft, heat dissipation fins for the stirring motor, and stirring fins for the reactor.

[0013] The stirring power is provided by the reactor stirring motor. A certain length of reactor stirring motor heat dissipation fins are set between the reactor stirring motor and the reactor stirring shaft to protect the reactor stirring motor. Reactor stirring fins are welded to the lower part of the reactor stirring shaft. An internal flow circulating water cooling structure is set at the connection between the reactor stirring motor heat dissipation fins and the reactor stirring shaft. The reactor stirring fins are of the structure of ribbon type, spiral type or paddle type fins.

[0014] Preferably, the distance between the stirring fins of the reactor and the inner wall of the reactor is 3-5 mm.

[0015] Preferably, the heat carrier heating reactor is equipped with an insertion-type temperature measuring point. After adding solid raw materials to the raw material pyrolysis reactor, the stirring of the heat carrier heating reactor is stopped, and a temperature probe is inserted into the temperature measuring point. The probe is held in place for a period of time to observe and record the temperature of the material inside the reactor. Before starting the stirring, the temperature probe is pulled out to a safe position, and then the stirring is started. The inside of the insertion-type temperature measuring point of the reactor is made of hard seal to ensure the sealing of the heat carrier heating reactor when inserting and removing the temperature probe.

[0016] Preferably, the outlet of the last stage condenser is connected to the inlet of the gas induced draft fan, and the outlet of the gas induced draft fan is connected to a gas flow meter. The amount of gas collected in the gas bag and the recorded amount of the gas flow meter are cross-verified to more accurately measure the amount of non-condensable pyrolysis gas.

[0017] Preferably, the heat carrier heating reactor / raw material pyrolysis reactor is equipped with an electric lifting structure, which separates the reactor shell from the outer heat jacket after the pyrolysis reaction is completed, thereby accelerating the natural cooling of the reactor.

[0018] Preferably, the 90° bends of the pipes connecting the inlet and outlet of the condenser are provided with detachable access ports in both the horizontal and vertical directions for pipe maintenance and cleaning of pyrolysis products.

[0019] A biomass pyrolysis method utilizing the aforementioned biomass dual-mode heating pyrolysis reactor and oil / gas condensation and collection device includes:

[0020] Select the heating mode. If you select the direct heating mode, the process is as follows:

[0021] S1. Preparations before pyrolysis;

[0022] S2. Add a certain amount of solid heat carrier to the heat carrier heating reactor, start the stirring motor of the heat carrier heating reactor, and set the stirring speed to 50% to 80% of the maximum speed. At the same time, start the heating function of the heat carrier heating reactor. Based on the heat calculation results of the mass ratio of heat carrier to solid raw material (3 to 7) and the final pyrolysis temperature (400 to 600℃), set the heating endpoint temperature to 800 to 900℃. During the heating process of the heat carrier, add a certain amount of solid raw material to the raw material pyrolysis reactor. Stop the stirring of the heat carrier heating reactor, insert the temperature probe into the heat carrier heating reactor from the insertion temperature measuring point, and proceed to the next step only after the temperature of the heat carrier in the heat carrier reactor reaches the set endpoint temperature.

[0023] S3. Start the heat carrier conveying screw and adjust the speed to 30-60% of the maximum speed. Open the hand valve between the heat carrier heating reactor and the heat carrier conveying screw. Adjust the stirring motor of the heat carrier heating reactor to reverse and the speed to 30-60% of the maximum speed. Gradually adjust the speed to 100% of the maximum speed.

[0024] S4. The solid heat carrier heated to the final temperature is transported to the raw material pyrolysis reactor through the heat carrier conveying screw within a certain time. It directly contacts and mixes with the solid raw material in the raw material pyrolysis reactor. Under oxygen-free conditions, the solid heat carrier is used as a heat source to heat the solid raw material. The solid heat carrier and the solid raw material are fully and evenly mixed in the raw material pyrolysis reactor, and the solid raw material undergoes a pyrolysis reaction.

[0025] S5. After the reaction is completed, introduce room temperature nitrogen into the device and monitor the temperature inside the reactor using the insertion temperature measuring point. When the temperature inside the reactor drops to room temperature, turn off the nitrogen supply, open the outlet of the pyrolysis reaction residue or heat carrier and collect the discharged pyrolysis reaction residue; collect the non-condensable pyrolysis gas in the gas bag and the pyrolysis oil stored in the oil tank during the condensation process.

[0026] If the indirect heating mode is selected, the processing procedure is as follows:

[0027] A1. Preparations before pyrolysis: A certain amount of solid raw material is added to both the heat carrier heating reactor and the raw material pyrolysis reactor.

[0028] A2. Start the heating program of the heat carrier heating reactor. After the pyrolysis reaction is completed, stop heating and close the outlet valve of the heat carrier heating reactor. The heat carrier heating reactor enters the cooling stage. After cooling down to room temperature, add a certain amount of solid raw materials to the heat carrier heating reactor again.

[0029] A3. Open the outlet valve and heating function of the raw material pyrolysis reactor. After the pyrolysis reaction is completed, stop the heating program and close the outlet valve of the raw material pyrolysis reactor. The raw material pyrolysis reactor enters the cooling stage. After cooling to room temperature, add a certain amount of solid raw material to the raw material pyrolysis reactor again; return to A2.

[0030] A4, Execute S5.

[0031] The advantages of this invention compared to the prior art are:

[0032] (1) This device is equipped with two heating and working modes: direct heating and indirect heating. The effects of the two heating methods on product composition and yield can be compared, providing detailed basic experimental data for engineering applications.

[0033] (2) This device is equipped with a four-stage condensation equipment. By adjusting the temperature of the condensing medium in the condenser, different fractions of pyrolysis oil products can be obtained. The reaction residue is discharged from the outlet of the reaction vessel, and the non-condensable pyrolysis gas is collected in the gas bag after passing through the flow meter, which can realize the fine collection and analysis of the products.

[0034] (3) To address the problem of inaccurate temperature measurement of solid materials inside an externally heated reactor, the device is equipped with an insertion temperature measuring point, which can measure the real temperature of solid materials inside the reactor in real time.

[0035] (4) The reactor system and equipment such as oil and gas condensation and fan flow are integrated in different skid-mounted devices, which facilitates the disassembly, assembly and maintenance of the device.

[0036] (5) The stirring fins of the reactor are spiral ribbon fins, which can realize the material turning up and down during the stirring process, so as to make the material evenly mixed; the distance between the stirring fins of the reactor and the inner wall of the reactor is 3-5mm. When the stirring motor of the reactor is started, it can scrape off the material adhering to the inner wall, preventing the material from coking on the inner wall of the reactor. Attached Figure Description

[0037] Figure 1 This invention relates to a dual-mode biomass pyrolysis reactor and an oil and gas condensation and collection device.

[0038] Figure 2 This is a schematic diagram of the structure of the heat carrier heating reactor a and the raw material pyrolysis reactor c according to the present invention;

[0039] Figure 3 Schematic diagram of the spiral structure b for transporting heat carrier

[0040] In the diagram: Heat carrier heated reactor a, reactor stirring shaft a1, reactor stirring fins a2, reactor bottom discharge screw a3, pyrolysis residue or heat carrier outlet a4, replacement nitrogen inlet a5, reactor external heat jacket a6, heat carrier or raw material inlet a7, reactor pressure measuring point a8, material silo a9, reactor stirring motor a10, reactor stirring motor heat dissipation fins a11, reactor insertion temperature measuring point a12, pyrolysis oil and gas product outlet a13, reactor flange cover a14; heat carrier conveying screw b, heat carrier conveying screw motor b1, heat carrier conveying screw heat dissipation fins b2, heat carrier... b3: Shaftless blades for conveying the bulk material; b4: spiral shell for conveying the heat carrier; b5: spiral inlet; b6: spiral outlet; c: raw material pyrolysis reactor; d: pyrolysis residue tray; e: insulated and heat-tracing pipe; f: primary condenser; f1: pipe access port; f2: primary heat transfer oil; f3: primary oil collection tank; g: secondary condenser; g1: pipe access port; g2: secondary heat transfer oil; g3: secondary oil collection tank; h: tertiary condenser; h1: pipe access port; h2: tertiary cooling water; h3: tertiary oil collection tank; i: quaternary condenser; i1: pipe access port; i2: quaternary cooling water; i3: quaternary oil collection tank; j: gas induced draft fan; k: gas flow meter; l: air bag. Detailed Implementation

[0041] The present invention will be further described below with reference to the embodiments.

[0042] Existing biomass pyrolysis technologies are mainly divided into two categories according to the heating method: direct heating and indirect heating. Each of the two pyrolysis methods has its own advantages and disadvantages. In order to better study the reaction mechanism and product analysis of biomass pyrolysis, a biomass dual-mode heating pyrolysis reactor and an integrated oil and gas condensation and collection device are provided. This device can integrate the two heating methods into one, and the products can be collected in stages by condensation to accurately analyze the products.

[0043] A biomass dual-mode heating pyrolysis reactor and an integrated oil and gas condensation and collection device includes a heat carrier heating reactor a, a heat carrier conveying screw b, a raw material pyrolysis reactor c, a pyrolysis residue tray d, an insulated and heat-tracing pipe e, a primary condenser f, a secondary condenser g, a tertiary condenser h, a quaternary condenser i, a gas induced draft fan j, a gas flow meter k, and an air bag l.

[0044] Among them, the heat carrier heating reactor a can be used to heat the heat carrier or raw materials, while the raw material pyrolysis reactor c is only used to heat the raw materials. The two reactors have the same structure and specifications.

[0045] Among them, the heat carrier heated reactor a and the raw material pyrolysis reactor c include reactor stirring shaft a1, reactor stirring fins a2, reactor bottom discharge spiral a3, pyrolysis reaction residue or heat carrier outlet a4, replacement nitrogen inlet a5, reactor external heat jacket a6, heat carrier or raw material inlet a7, reactor pressure measuring point a8, material bin a9, reactor stirring motor a10, reactor stirring motor heat dissipation fins a11, reactor insertion temperature measuring point a12, pyrolysis oil and gas product outlet a13, and reactor flange cover plate a14;

[0046] The heat carrier conveying spiral b includes a heat carrier conveying spiral motor b1, heat carrier conveying spiral heat dissipation fins b2, heat carrier conveying spiral shaftless blades b3, heat carrier conveying spiral shell b4, spiral inlet b5, and spiral outlet b6. The pyrolysis reaction residue or heat carrier outlet a4 is connected to the spiral inlet b5, and the spiral outlet b6 is connected to the heat carrier or raw material inlet a7 of the raw material pyrolysis reactor c.

[0047] The primary condenser f includes a pipeline access port f1, primary heat transfer oil f2, and primary oil collection tank f3; the secondary condenser g includes a pipeline access port g1, secondary heat transfer oil g2, and secondary oil collection tank g3; the tertiary condenser h includes a pipeline access port h1, tertiary cooling water h2, and tertiary oil collection tank h3; and the quaternary condenser i includes a pipeline access port i1, quaternary cooling water i2, and quaternary oil collection tank i3.

[0048] The reactor a has an upper cylindrical structure and a lower conical structure. A flange cover a14 is installed on top of the cylindrical body. Both the reactor body and the flange cover are made of alloy stainless steel, with a maximum temperature resistance of 850℃. The reactor has a heat carrier or raw material inlet a7, a pyrolysis reaction outlet a12, and a pyrolysis reaction residue or heat carrier outlet a4. The heat carrier heating method for reactor a is jacketed external heating. The heating jacket is a one-piece, electrically heated, detachable structure for easy equipment inspection and maintenance.

[0049] The stirring function of the reactor is achieved through a stirring mechanism, with the stirring power provided by a stirring motor a10. A certain length of heat dissipation fins a11 are installed between the stirring motor a10 and the stirring shaft a1 to protect the stirring motor a10. Stirring fins a2 are welded to the lower part of the stirring shaft a1. An internal flow circulating water cooling structure is installed at the connection between the heat dissipation fins a11 and the stirring shaft a1, further reducing heat conduction from the stirring shaft a1 to the stirring motor a10, thus better protecting the stirring motor a10. The stirring fins a2 have a ribbon, spiral, or paddle-type structure, which can achieve up-and-down movement of the material during stirring, thereby ensuring uniform mixing. The distance between the stirring fins a2 and the inner wall of the reactor a is 3-5mm. When the stirring motor a10 starts, it can scrape off the material adhering to the inner wall, preventing coking of the material on the inner wall of the reactor a. In addition, to accelerate the natural cooling time of the reactor, the reactor is equipped with an electric lifting structure, which can separate the reactor shell from the external heat jacket a6 after the pyrolysis reaction is completed, thereby improving work efficiency.

[0050] The operating mode of the insertion-type temperature measuring point a12 in the reactor is as follows: When stirring stops, the temperature probe is inserted into the reactor and held for a period of time to observe and record the temperature of the material inside the reactor; before stirring is started, the temperature probe is pulled out to a safe position, and then stirring is started. The interior of the insertion-type temperature measuring point a12 in the reactor is made of hard seal material, which ensures the sealing of reactor a when the temperature probe is inserted or removed.

[0051] The device is equipped with four condensers, each a shell-and-tube heat exchanger. Each condenser contains a cooling medium and an oil collection tank. The temperature of the cooling medium can be adjusted within a certain range, allowing for the collection of different fractions of pyrolysis oil products based on the characteristics of the solid material's pyrolysis products. The cooling medium in the first-stage condenser (f) and the second-stage condenser (g) is heat transfer oil, used to cool and collect higher fractions of pyrolysis oil products. The pyrolysis oil gas discharged from outlet a13 has a high dust content; therefore, the tube dimensions of the first-stage condenser (f) and the second-stage condenser (g) are set larger than those of the third-stage condenser (h) and the fourth-stage condenser (i) to prevent blockage due to high dust content. The cooling medium in the third-stage condenser (h) and the fourth-stage condenser (i) is cooling water, with the fourth-stage condenser using low-temperature cooling water to achieve deep cooling of the pyrolysis oil gas, maximizing the collection of pyrolysis oil products. Additionally, the 90° bends in the pipes connecting the condenser inlet and outlet are equipped with detachable horizontal and vertical access ports for pipe maintenance and pyrolysis product cleaning.

[0052] This device can achieve both direct and indirect heating of materials, thus allowing for a comparison of the effects of the two heating methods on product composition and yield.

[0053] One heating mode is as follows: the heat carrier heating reactor a and the raw material pyrolysis reactor c are used to heat the solid heat carrier and the solid raw material, respectively. The solid heat carrier can be ceramic sand, corundum, quartz sand, steel ball particles, etc., and the solid raw material can be various biomass such as reed, jujube shell, and corn stalk.

[0054] The specific process is described as follows: First, check that the system's airtightness is normal and that the system replacement is complete. Check that the system's instrument valves are powered normally and that the utilities are ready. Add a certain amount of solid heat carrier to the heat carrier heating reactor a through the heat carrier inlet a7 or raw material inlet a7. Start the stirring motor a10 of the heat carrier heating reactor, setting the stirring speed to 50%–80% of the maximum speed. Simultaneously, start the programmed heating function of the reactor's external heating jacket a6. Based on the heat calculation results of the mass ratio of heat carrier to solid raw material (3–7) and the final pyrolysis temperature (400–600℃), set the heating endpoint temperature to 800–900℃. During the heating process, add a certain amount of solid raw material to the raw material pyrolysis reactor c through the heat carrier inlet a7 or raw material inlet a7. Stop stirring in the heat carrier heating reactor a. Insert the reactor's insertion temperature measuring point a12 into the heat carrier heating reactor a. Only after the temperature of the heat carrier inside the reactor reaches the set endpoint temperature can the next step be performed.

[0055] Start the heat carrier conveying screw b and adjust the speed to 50% of the maximum speed. Open the hand valve between the heat carrier heating reactor a and the heat carrier conveying screw b. Adjust the heat carrier heating reactor stirring motor a10 to reverse and the speed to 50% of the maximum speed. Gradually adjust the speed to 100% of the maximum speed. Reversing the stirring motor a10 is beneficial for the material discharge from the reactor and can save discharge time.

[0056] The solid heat carrier, heated to the final temperature, is conveyed to the raw material pyrolysis reactor c via the heat carrier conveying screw b within a certain time. It directly contacts and mixes with the solid raw material in reactor c. Under oxygen-free conditions, the solid heat carrier acts as a heat source to heat the solid raw material. Under the stirring action of the reactor's stirring fins a2, the solid heat carrier and solid raw material are thoroughly and uniformly mixed, and the solid raw material undergoes a pyrolysis reaction. The solid raw material pyrolysis reaction produces high-temperature pyrolysis oil and gas and pyrolysis residue. The high-temperature pyrolysis oil and gas is discharged through the pyrolysis oil and gas product outlet a13, and after passing through the insulated and heated pipe e, it connects to the inlet of the first-stage condenser f. The outlet of the first-stage condenser f connects to the inlet of the second-stage condenser g. The outlet of the second-stage condenser g connects to the inlet of the third-stage condenser h. The outlet of the third-stage condenser h connects to the inlet of the fourth-stage condenser i. The non-condensable pyrolysis gas passes through the outlet of the fourth-stage condenser i and connects to the inlet of the gas induced draft fan j. The outlet of the gas induced draft fan j is connected to a gas flow meter k. The non-condensable pyrolysis gas is finally collected in a compressible gas bag l. The airbag l is compressible. Before the experiment begins, the airbag l is compressed to expel the non-reaction product gas. The product gas collected in the airbag l can be used as sample gas for detection and analysis. The amount of gas collected in the airbag l and the recorded amount of the gas flow meter k are cross-validated to facilitate more accurate measurement of the amount of non-condensable pyrolysis gas.

[0057] Another heating mode involves both the heat carrier heating reactor a and the raw material pyrolysis reactor c heating the solid raw material. The two reactors react alternately, increasing the pyrolysis throughput and achieving rapid oil recovery. The specific operation is as follows: After completing the pre-experiment preparation and checks, a certain amount of solid raw material is added to both reactors. The heating program of the heat carrier heating reactor a is started. After the pyrolysis reaction is completed, the heating program of the external heating jacket a6 of the heat carrier heating reactor a is stopped, and the outlet valve of the heat carrier heating reactor a is closed. The heat carrier heating reactor a then enters the cooling stage. After cooling to room temperature, a certain amount of solid raw material can be added to the heat carrier heating reactor a again. The outlet valve and program heating function of the raw material pyrolysis reactor c are then opened. After the pyrolysis reaction is completed, the heating program of the external heating jacket a6 of the raw material pyrolysis reactor c is stopped, and the outlet valve of the raw material pyrolysis reactor c is closed. The raw material pyrolysis reactor c then enters the cooling stage. After cooling to room temperature, a certain amount of solid raw material can be added to the raw material pyrolysis reactor c again. At this point, the heating program of the heat carrier heating reactor a can be restarted. The two reactors are switched alternately in this way to increase the throughput of pyrolysis materials and the yield of products.

[0058] To perform product analysis on the pyrolysis reaction products, accurate collection and weighing of the pyrolysis products are required. After the reaction, the pyrolysis residue is discharged from the pyrolysis residue or heat carrier outlet a4, collected, and weighed. Pyrolysis residue adhering to the inner wall of the reactor is cleaned and discharged by the scraping action of the reactor's stirring fins a2. The pyrolysis oil and gas are cooled by a four-stage condenser and collected into different fractions of pyrolysis oil, stored in oil collection tanks at each stage. Non-condensable pyrolysis gas is collected and stored in gas bladder l, and the cumulative volume of non-condensable pyrolysis gas is recorded by gas flow meter k.

[0059] The present invention uses cascade adjustment of the gas induced draft fan frequency and the pressure signal of the reactor to achieve stable control of the reactor pressure.

[0060] Example

[0061] like Figure 2 As shown, the upper part of the reactor a is a cylindrical structure and the lower part is a conical structure. A reactor flange cover plate a14 is installed on the top of the cylinder. The reactor cylinder and the flange cover plate are made of alloy stainless steel, which can withstand temperatures up to 850℃.

[0062] The stirring function of the reactor is achieved through a stirring mechanism, with the stirring power provided by a reactor stirring motor a10. A 30-50cm long heat dissipation fin a11 is installed between the reactor stirring motor a10 and the reactor stirring shaft a1 to protect the reactor stirring motor a10. Reactor stirring fins a2 are welded to the lower part of the reactor stirring shaft a1. An internal flow circulating water cooling structure is installed at the connection between the reactor stirring motor heat dissipation fins a11 and the reactor stirring shaft a1. The inlet temperature of the circulating water is 20-30℃, further reducing heat conduction from the reactor stirring shaft a1 to the reactor stirring motor a10, thereby better protecting the reactor stirring motor a10. The stirring fins a2 of the reactor have a structure of ribbon, spiral, and paddle-type fins, which can realize the up-and-down movement of materials during the stirring process, thereby ensuring uniform mixing. The distance between the stirring fins a2 and the inner wall of the reactor a is 3-5mm. When the stirring motor a10 starts, it can scrape off the material adhering to the inner wall, preventing coking. In addition, to accelerate the natural cooling time of the reactor, the reactor is equipped with an electric lifting structure, which can separate the reactor shell from the outer heating jacket a6 after the pyrolysis reaction is completed, thereby improving working efficiency.

[0063] The operating mode of the insertion-type temperature measuring point a12 in the reactor is as follows: When stirring is stopped, the temperature probe is inserted into the reactor and held for a period of time to observe and record the temperature of the material inside the reactor. The measuring range of the temperature measuring point is 25–1000℃. Before stirring is started, the temperature probe is pulled out to a safe position, and then stirring is started. The internal structure of the insertion-type temperature measuring point a12 in the reactor is rigidly sealed, ensuring the sealing of the reactor during the insertion and removal of the temperature probe.

[0064] The device is equipped with four condensers, each a shell-and-tube heat exchanger. Each condenser has a cooling medium and an oil collection tank. The temperature of the cooling medium can be adjusted within a certain range, allowing for the collection of pyrolysis oil products of different fractions based on the characteristics of the solid material's pyrolysis products. The cooling medium in the primary condenser (f) and secondary condenser (g) is heat transfer oil, used to cool and collect higher fraction pyrolysis oil products. The pyrolysis gas outlet temperature of primary condenser (f) is maintained above 350℃, while that of secondary condenser (g) is 200–250℃. The pyrolysis oil gas discharged from outlet a13 has a high dust content; therefore, the tube dimensions of primary condenser (f) and secondary condenser (g) are set larger than those of tertiary condenser (h) and quaternary condenser (i) to prevent tube blockage due to high dust content. The tube diameters of the four condensers are as follows: The cooling medium for both the third-stage condenser h and the fourth-stage condenser i is cooling water. The fourth-stage condenser i uses low-temperature cooling water, which deeply cools the pyrolysis oil and gas, maximizing the collection of pyrolysis products. The pyrolysis gas outlet temperatures for the third-stage condenser h and the fourth-stage condenser i range from 100 to 150°C and 10 to 20°C, respectively. Additionally, the 90° bends in the pipes connecting the condenser inlet and outlet are equipped with detachable horizontal and vertical access ports for pipe maintenance and cleaning of pyrolysis products.

[0065] As attached Figure 1 As shown, this device can achieve both direct and indirect heating of materials, thus allowing for a comparison of the effects of the two heating methods on product composition and yield.

[0066] Mode 1: The heat source for heating solid raw materials is a solid heat carrier.

[0067] Step 1: Confirm that the device and its auxiliary systems meet the airtightness requirements for start-up according to relevant specifications. Before start-up, the device must be purged with inert gas, which is generally room temperature nitrogen. The purging time is determined according to the room temperature nitrogen flow rate and the device volume. The purging time is 15 minutes. After the purging is completed, turn off the purging nitrogen and record the cumulative nitrogen flow rate of the gas flow meter k.

[0068] Step 2: A certain amount of solid heat carrier is added to the heat carrier heating reactor a through the heat carrier or raw material inlet a7. The mass of the solid heat carrier is 20 kg. The stirring motor a10 of the heat carrier heating reactor is started, and the stirring speed is set to 60% of the maximum speed. At the same time, the program heating function of the external heat jacket a6 of the reactor is started. Based on the mass ratio of heat carrier to solid raw material (5:1) and the heat calculation results of pyrolysis final temperature of 450℃, the heating endpoint temperature is set to 850℃.

[0069] Step 3: During the heating process, a certain amount of solid raw material is added to the raw material pyrolysis reactor c through the heat carrier or raw material inlet a7. The mass ratio of heat carrier to solid raw material is 3-7. Stirring in the reactor is stopped. The reactor insertion temperature measuring point a12 is inserted into the heat carrier heating reactor a. The next step can only proceed after the temperature of the heat carrier in the reactor reaches the set endpoint temperature, which is 850℃.

[0070] Step 4: Start the heat carrier conveying screw b and adjust its speed to 50% of the maximum speed. Open the hand valve between the heat carrier heating reactor a and the heat carrier conveying screw b. Adjust the stirring motor a10 of the heat carrier heating reactor to reverse and its speed to 50% of the maximum speed. Gradually adjust the speed to 100% of the maximum speed. Reversing the stirring motor a10 is beneficial for the material discharge from the reactor and can save discharge time. After 10 to 15 minutes, all the heated heat carrier can be transported to the raw material pyrolysis reactor c.

[0071] Step 5: The solid heat carrier heated to the final temperature is transported to the raw material pyrolysis reactor c through the heat carrier conveying screw b within a certain time. It directly contacts and mixes with the solid raw material in the raw material pyrolysis reactor c. Under oxygen-free conditions, the solid heat carrier is used as a heat source to heat the solid raw material. Under the stirring action of the stirring fins a2 in the reactor, the solid heat carrier and the solid raw material are fully mixed and homogeneous, and the solid raw material undergoes a pyrolysis reaction.

[0072] Step six: The solid raw material pyrolysis reaction produces high-temperature pyrolysis oil and gas and pyrolysis residue. The high-temperature pyrolysis oil and gas is discharged through the pyrolysis oil and gas product outlet a13, the diameter of which is [missing information]. After passing through the insulated and heat-traced pipe e, it connects to the inlet of the first-stage condenser f. The outlet of the first-stage condenser f connects to the inlet of the second-stage condenser g. The outlet of the second-stage condenser g connects to the inlet of the third-stage condenser h. The outlet of the third-stage condenser h connects to the inlet of the fourth-stage condenser i. The non-condensable pyrolysis gas, after passing through the outlet of the fourth-stage condenser i, connects to the inlet of the gas induced draft fan j. The gas flow rate of the gas induced draft fan j is selected from 20 to 300 m³ / h. 3 / h, the outlet of the gas induced draft fan j is connected to a gas flow meter k, which has real-time and cumulative gas flow monitoring functions; the non-condensable pyrolysis gas is finally collected in a compressible gas bladder l, the volume of which is 2-10m³. 3 The gasbag l is compressible. Before the experiment begins, the gasbag l is compressed to expel the non-reactive product gas. The product gas collected in the gasbag l can be used as sample gas for detection and analysis. The amount of gas collected in the gasbag l and the recorded amount of the gas flow meter k are cross-validated to facilitate more accurate measurement of the amount of non-condensable pyrolysis gas.

[0073] Step 7: After the reaction is complete, introduce room temperature nitrogen into the nitrogen inlet a5 for 10-15 minutes. Monitor the temperature inside the reactor using the insertion temperature measuring point a12. When the temperature inside the reactor drops to room temperature, close the nitrogen inlet, open the pyrolysis reaction residue or heat carrier outlet a4, collect the discharged pyrolysis reaction residue, weigh it, and record the amount of pyrolysis residue.

[0074] Step 8: Remove and open the primary oil collection tank f3, secondary oil collection tank g3, tertiary oil collection tank h3 and quaternary oil collection tank i3 respectively, clean the oil phase substances in the condenser connecting pipes and collect them into the quaternary oil collection tank respectively, weigh and measure the pyrolysis oil of different fractions.

[0075] Step 9: Record the cumulative flow of gas flow meter k throughout the experiment. Subtract the cumulative gas flow of nitrogen replacement before the experiment to get the amount of non-condensable pyrolysis gas produced by the pyrolysis of the raw materials in this experiment. The non-condensable pyrolysis gas collected in gas bag l can be stored and sent for analysis.

[0076] Mode 2: The heat source for heating solid raw materials is the external heating jacket of the reactor.

[0077] Step one is the same as step one in pattern one.

[0078] Step 2: Add a certain amount of solid raw material to both reactors, start the heating program of reactor a heated by the heat carrier, and stop the heating program of the outer heat jacket a6 of reactor a heated by the heat carrier after the pyrolysis reaction is completed. Close the outlet valve of reactor a heated by the heat carrier and reactor a enters the cooling stage. After cooling down to room temperature, a certain amount of solid raw material can be added to reactor a heated by the heat carrier again.

[0079] Step 3: Open the outlet valve and program heating function of the raw material pyrolysis reactor C. After the pyrolysis reaction is completed, stop the heating program of the external heating jacket a6 of the raw material pyrolysis reactor C, and close the outlet valve of the raw material pyrolysis reactor C. The raw material pyrolysis reactor C then enters the cooling stage. After cooling to room temperature, a certain amount of solid raw material can be added to the raw material pyrolysis reactor C again. At this time, the heating program of the heat carrier heating reactor a can be restarted. The two reactors are switched alternately in this way to increase the throughput of pyrolysis materials and the yield of products.

[0080] Steps four through seven are the same as steps six through nine in Pattern One.

[0081] The parts of this invention not described in detail are common knowledge to those skilled in the art.

Claims

1. A biomass dual-mode heating pyrolysis reactor and oil / gas condensation and collection device, comprising a heat carrier heating reactor, a heat carrier conveying screw, a raw material pyrolysis reactor, a pyrolysis residue tray, an insulated and heat-tracing pipeline, a gas induced draft fan, a condenser, a gas flow meter, and a gas bag; characterized in that: The device has two operating modes, including direct heating mode and indirect heating mode; In direct heating mode: the heat carrier heating reactor is used to heat the solid heat carrier, and the solid raw material is added to the raw material pyrolysis reactor; after the heat carrier in the heat carrier heating reactor is heated to the set endpoint temperature, it is transported to the raw material pyrolysis reactor by the heat carrier conveying screw. Under oxygen-free conditions, the solid heat carrier is used as a heat source to heat the solid raw material and is stirred evenly in the raw material pyrolysis reactor to carry out the pyrolysis reaction. In the indirect heating mode: both the heat carrier heating reactor and the raw material pyrolysis reactor are used to heat the solid raw material for pyrolysis reaction, and the two reactors react alternately; In both modes, the cracked oil and gas generated by the pyrolysis reaction are discharged through the pyrolysis oil and gas product outlet of the reactor. After passing through a multi-stage condenser, the non-condensable pyrolysis gas is collected in a gas bag.

2. The apparatus according to claim 1, characterized in that: The condenser includes a first-stage condenser, a second-stage condenser, a third-stage condenser, and a fourth-stage condenser connected in series. All condensers are shell-and-tube heat exchangers. Each condenser is equipped with a cooling medium and an oil collection tank. The cooling medium for the first-stage and second-stage condensers is heat transfer oil, while the cooling medium for the third-stage and fourth-stage condensers is cooling water. The tube dimensions of the first-stage and second-stage condensers are larger than those of the third-stage and fourth-stage condensers.

3. The apparatus according to claim 2, characterized in that: The pyrolysis gas outlet temperature of the first-stage condenser is maintained above 350℃, the pyrolysis gas outlet temperature of the second-stage condenser is 200-250℃, and the pyrolysis gas outlet temperature ranges of the third-stage and fourth-stage condensers are 100-150℃ and 10-20℃, respectively.

4. The apparatus according to claim 1, characterized in that: The stirring functions of both the heat carrier heating reactor and the raw material pyrolysis reactor are achieved through a stirring mechanism, which includes a stirring motor, a stirring shaft, heat dissipation fins for the stirring motor, and stirring fins for the reactor. The stirring power is provided by the reactor stirring motor. A certain length of reactor stirring motor heat dissipation fins are set between the reactor stirring motor and the reactor stirring shaft to protect the reactor stirring motor. Reactor stirring fins are welded to the lower part of the reactor stirring shaft. An internal flow circulating water cooling structure is set at the connection between the reactor stirring motor heat dissipation fins and the reactor stirring shaft. The reactor stirring fins are of the structure of ribbon type, spiral type or paddle type fins.

5. The apparatus according to claim 4, characterized in that: The distance between the stirring fins and the inner wall of the reactor is 3-5 mm.

6. The apparatus according to claim 1, characterized in that: The heat carrier heating reactor is equipped with an insertion-type temperature measuring point. After adding solid raw materials to the raw material pyrolysis reactor, the stirring of the heat carrier heating reactor is stopped, and a temperature probe is inserted into the temperature measuring point. The probe is held in place for a period of time to observe and record the temperature of the material inside the reactor. Before starting the stirring, the temperature probe is pulled out to a safe position, and then the stirring is started. The inside of the insertion-type temperature measuring point of the reactor is made of hard seal to ensure the sealing of the heat carrier heating reactor when inserting and removing the temperature probe.

7. The apparatus according to claim 1, characterized in that: The outlet of the final stage condenser is connected to the inlet of the gas induced draft fan, and the outlet of the gas induced draft fan is connected to a gas flow meter. The amount of gas collected in the gas bag and the amount recorded by the gas flow meter are cross-verified to more accurately measure the amount of non-condensable pyrolysis gas.

8. The apparatus according to claim 1, characterized in that: The heat carrier heating reactor / raw material pyrolysis reactor is equipped with an electric lifting structure, which separates the reactor shell from the outer heat jacket after the pyrolysis reaction is completed, thereby accelerating the natural cooling of the reactor.

9. The apparatus according to claim 1, characterized in that: The pipes connecting the inlet and outlet of the condenser are equipped with detachable horizontal and vertical inspection ports at the 90° bends for pipe maintenance and cleaning of pyrolysis products.

10. A biomass pyrolysis method utilizing the biomass dual-mode heating pyrolysis reactor and oil-gas condensation and collection device as described in claim 4, characterized in that: Select the heating mode. If you select the direct heating mode, the process is as follows: S1. Preparations before pyrolysis; S2. Add a certain amount of solid heat carrier to the heat carrier heating reactor, start the stirring motor of the heat carrier heating reactor, and set the stirring speed to 50% to 80% of the maximum speed. At the same time, start the heating function of the heat carrier heating reactor. Based on the heat calculation results of the mass ratio of heat carrier to solid raw material (3 to 7) and the final pyrolysis temperature (400 to 600℃), set the heating endpoint temperature to 800 to 900℃. During the heating process of the heat carrier, add a certain amount of solid raw material to the raw material pyrolysis reactor. Stop the stirring of the heat carrier heating reactor, insert the temperature probe into the heat carrier heating reactor from the insertion temperature measuring point, and proceed to the next step only after the temperature of the heat carrier in the heat carrier reactor reaches the set endpoint temperature. S3. Start the heat carrier conveying screw and adjust the speed to 30-60% of the maximum speed. Open the hand valve between the heat carrier heating reactor and the heat carrier conveying screw. Adjust the stirring motor of the heat carrier heating reactor to reverse and the speed to 30-60% of the maximum speed. Gradually adjust the speed to 100% of the maximum speed. S4. The solid heat carrier heated to the final temperature is transported to the raw material pyrolysis reactor through the heat carrier conveying screw within a certain time. It directly contacts and mixes with the solid raw material in the raw material pyrolysis reactor. Under oxygen-free conditions, the solid heat carrier is used as a heat source to heat the solid raw material. The solid heat carrier and the solid raw material are fully and evenly mixed in the raw material pyrolysis reactor, and the solid raw material undergoes a pyrolysis reaction. S5. After the reaction is completed, introduce room temperature nitrogen into the device and monitor the temperature inside the reactor using the insertion temperature measuring point. When the temperature inside the reactor drops to room temperature, turn off the nitrogen supply, open the outlet of the pyrolysis reaction residue or heat carrier and collect the discharged pyrolysis reaction residue; collect the non-condensable pyrolysis gas in the gas bag and the pyrolysis oil stored in the oil tank during the condensation process. If the indirect heating mode is selected, the processing procedure is as follows: A1. Preparations before pyrolysis: A certain amount of solid raw material is added to both the heat carrier heating reactor and the raw material pyrolysis reactor. A2. Start the heating program of the heat carrier heating reactor. After the pyrolysis reaction is completed, stop heating and close the outlet valve of the heat carrier heating reactor. The heat carrier heating reactor enters the cooling stage. After cooling down to room temperature, add a certain amount of solid raw materials to the heat carrier heating reactor again. A3. Open the outlet valve and heating function of the raw material pyrolysis reactor. After the pyrolysis reaction is completed, stop the heating program and close the outlet valve of the raw material pyrolysis reactor. The raw material pyrolysis reactor enters the cooling stage. After cooling to room temperature, add a certain amount of solid raw material to the raw material pyrolysis reactor again; return to A2. A4, Execute S5.

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