A continuous production system for hydrothermal carbonization of high-water-content organic solid waste

Abstract

This invention discloses a continuous hydrothermal carbonization production system for high-moisture-content organic solid waste, belonging to the field of organic solid waste treatment technology. It includes a heating oil furnace, a reaction vessel, preheating equipment, cooling equipment, and solid-liquid separation equipment. After preheating in the preheating equipment, the organic solid waste enters the reaction vessel for hydrothermal carbonization, forming a biochar slurry. This slurry is then cooled in the cooling equipment and separated by the solid-liquid separation equipment to obtain biochar. The heat transfer oil in the heating oil furnace enters the reaction vessel's heat transfer oil sleeve via a heat transfer oil pump. The heat transfer oil in the reaction vessel's heat transfer oil sleeve preheats the high-moisture-content organic solid waste in the preheating equipment via the heat transfer oil pipe in the preheating section. Then, it enters the cooling section's heat transfer oil pipe to absorb heat from the biochar slurry and returns to the heating oil furnace. This forms a closed-loop circulation circuit for the heat transfer oil. Preheating the organic solid waste improves the reaction efficiency of the reaction vessel and shortens the residence time. The return of the heat transfer oil to the heating oil furnace after heat exchange with the biochar slurry saves electricity. The system also features high waste heat recovery rate, high reaction vessel utilization rate, and high production capacity.

Description

[0001] This invention is a divisional application of patent document CN116286137A; the application date of patent document CN116286137A is March 9, 2023, the application number is 202310222208.7, the patent name is continuous production system for hydrothermal carbonization of high water content organic solid waste, and the applicants are China Metallurgical Ecological Environmental Protection Group Co., Ltd. and Beijing Shunhong Jinjian Environmental Technology Development Co., Ltd. Technical Field

[0002] This invention belongs to the field of organic solid waste treatment technology, and in particular relates to a continuous production system for hydrothermal carbonization of high-moisture organic solid waste. Background Technology

[0003] Hydrothermal carbonization (HTC) technology is based on the high-pressure chemistry theory proposed by Friedrich Bergius, the German chemist who won the 1931 Nobel Prize in Chemistry. This method simulates the natural formation of coal, oil, and natural gas, reproducing this reaction process—which takes millions of years in nature—in a few hours under appropriate temperature, pressure, and pH conditions. The HTC reaction is carried out under conditions of evacuated air and added catalyst, at temperatures of 180-200°C and pressures of 20-35 bar, carbonizing organic materials (such as biological waste or sludge) into HTC biochar within hours. This method is conducted in an aquatic environment, thus eliminating the need for drying the input material, and is particularly suitable for water-rich biological organic waste and sludge. After dehydration, the HTC biochar has a low moisture content and, due to its high calorific value, can be used for climate-friendly power generation in coal-fired power plants or as a fossil fuel alternative in cement plants or waste incineration plants.

[0004] Industrial hydrothermal carbonization systems can be implemented using either batch or continuous production. Batch production involves feeding materials into the reactor in batches, heating them in a closed environment, and then subjecting them to a hydrothermal carbonization reaction at a fixed temperature and pressure. After the reaction time is reached, the materials are cooled, the reaction products are discharged, and the next batch is processed, repeating this cycle. Continuous production involves materials continuously entering the reaction system, remaining in the reactor for a fixed time, and then continuously discharging. Due to its low efficiency, batch production is generally only used for research and small-scale production applications and is not adopted for large-scale industrial production. Continuous production is suitable for large-scale industrial applications. Currently, there are few cases of continuous hydrothermal carbonization production, mainly due to the complexity of the process. The separation of reactor heating and waste heat recovery leads to reduced reactor efficiency and utilization. Furthermore, the inability to preheat materials during system startup makes system startup difficult. Additionally, the separation of the heating and waste heat recovery systems in existing reactors complicates control. Summary of the Invention

[0005] The purpose of this invention is to provide a continuous production system for hydrothermal carbonization of high-moisture organic solid waste, which aims to solve the technical problems of existing continuous hydrothermal carbonization production where the heating system and waste heat recovery system of the reactor are separated, resulting in complex processes and controls, and low reaction efficiency and utilization of the reactor.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A continuous hydrothermal carbonization production system for high-moisture-content organic solid waste includes a heating oil furnace, a reactor, a preheating device, a cooling device, and a solid-liquid separation device. The outlet of the preheating device is connected to the inlet of the reactor, the outlet of the reactor is connected to the inlet of the cooling device, and the outlet of the cooling device is connected to the inlet of the solid-liquid separation device. The solid-liquid separation device is used to separate biochar from the biochar slurry. The heat transfer oil in the heating oil furnace is connected to the reactor heat transfer oil sleeve on the outer wall of the reactor via a heat transfer oil pump. The heat transfer oil in the reactor heat transfer oil sleeve is connected to the preheating section heat transfer oil pipe on the outer wall of the preheating device via a heat transfer oil pipe, allowing heat exchange between the organic solid waste and the heat transfer oil in the preheating device. The preheating section heat transfer oil pipe is connected to the cooling section heat transfer oil pipe on the outer wall of the cooling device via a heat transfer oil pipe, allowing heat exchange between the biochar slurry and the heat transfer oil in the cooling device. The cooling section heat transfer oil pipe returns to the heating oil furnace via a heat transfer oil pipe. The feed inlet of the preheating equipment is connected to the organic solid waste buffer bin via a booster pump; The reactor includes a horizontal tank and a stirring mechanism. The stirring mechanism includes a motor and a horizontally placed stirring shaft. The motor is located on the outside of the tank and connected to the end of the stirring shaft. The stirring shaft has a number of radially arranged stirring blades spaced apart.

[0007] Preferably, the outlet of the cooling device is connected to the biochar slurry storage tank via a pressure relief pump, and the biochar slurry is cooled to room temperature in the biochar slurry storage tank; the outlet of the biochar slurry storage tank is connected to the inlet of the solid-liquid separation device, and the solid outlet of the solid-liquid separation device is connected to the biochar storage tank.

[0008] Preferably, the heating oil furnace, the reactor heat transfer oil sleeve, the preheating section heat transfer oil pipe, the cooling section heat transfer oil pipe, and the heating oil furnace are sequentially connected to form a closed-loop heat transfer oil circulation circuit via heat transfer oil pipes. The heat transfer oil transmission process is as follows: (1) The heat transfer oil is heated in the heating oil furnace; (2) The heated heat transfer oil is pumped to the heat transfer oil sleeve of the reactor to maintain the reaction temperature inside the reactor. (3) After passing through the reactor, the heat transfer oil enters the heat transfer oil pipe of the preheating section of the preheating equipment. The organic solid waste is transported in the inner pipe of the preheating equipment from low temperature to high temperature and enters the reactor. The heat transfer oil is transported in the opposite direction from high temperature to low temperature in the heat transfer oil pipe of the preheating section outside the preheating equipment. (4) The heat transfer oil re-enters the heat transfer oil pipe of the cooling section of the cooling equipment. The biochar slurry discharged from the reactor is transported in the inner pipe of the cooling equipment from high temperature to low temperature. The heat transfer oil is transported in the opposite direction in the heat transfer oil pipe of the cooling section, from low temperature to high temperature. (5) After the heat transfer oil is output from the cooling equipment, it enters the heating oil furnace for heating and recycling. After the biochar slurry is cooled and the heat is recovered by the heat transfer oil, it is further cooled to room temperature in the biochar slurry storage chamber by the built-in condensate coil. After being dehydrated and dried by the solid-liquid separation equipment, it is transported for disposal.

[0009] Preferably, in step (1), the heating temperature of the heat transfer oil in the hot oil furnace is 180-230℃.

[0010] Preferably, in step (2), the reaction temperature of the reactants in the reactor is 160-210℃, and the residence time of the reactants is 0.5-3h.

[0011] Preferably, in step (3), the input temperature of the heat transfer oil in the preheating equipment is 180-230℃, the output temperature of the heat transfer oil is 60-100℃, the input temperature of the organic solid waste is 20-40℃, the output temperature is 160-210℃, and the residence time of the organic solid waste is 0.5-2h.

[0012] Preferably, in step (4), the input temperature of the heat transfer oil in the cooling device is 60-100℃, the output temperature of the heat transfer oil is 140-190℃, the input temperature of the biochar slurry is 160-210℃, the output temperature is 80-120℃, and the residence time of the biochar slurry is 0.5-2h.

[0013] Preferably, the high-moisture organic solid waste is dehydrated sludge, plant straw, or livestock and poultry manure.

[0014] The beneficial effects of adopting the above technical solution are as follows: Compared with the prior art, the present invention connects the heat transfer oil circuits of the reactor, preheating equipment, and cooling equipment in sequence to form a closed-loop circulation circuit with the heating oil furnace. The heat transfer oil is controlled by a heat transfer oil pump to ensure that the temperature of the organic solid waste entering the reactor after preheating by the heat transfer oil can reach the hydrothermal carbonization reaction temperature, thereby improving the reaction efficiency of the reactor and shortening the residence time. After the heat transfer oil exchanges heat with the organic solid waste, its temperature decreases. It then absorbs heat from the biochar slurry in the cooling equipment and returns to the heating oil furnace, which can save electricity consumption. After the heat transfer oil exchanges heat with the biochar slurry, it lowers the temperature of the biochar slurry and accelerates the cooling rate of the biochar slurry, thereby improving the production processing capacity. Attached Figure Description

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0016] Figure 1 This is a schematic diagram of the structure of a continuous production system for hydrothermal carbonization of high-moisture organic solid waste provided in an embodiment of the present invention; Figure 2 This is a flowchart of the heat transfer oil in this invention; Figure 3 This is a flowchart of the materials used in this invention; In the diagram: 1. Heating oil furnace; 2. Organic solid waste buffer silo; 3. Booster pump; 4. Organic solid waste; 5. Preheating section heat transfer oil pipe; 6. Reactants; 7. Stirrer; 8. Reactor; 9. Reactor heat transfer oil sleeve; 10. Biochar slurry; 11. Cooling section heat transfer oil pipe; 12. Pressure relief discharge pump; 13. Biochar slurry storage silo; 14. Preheating equipment; 15. Cooling equipment; 16. Heat transfer oil pump; 17. Solid-liquid separation equipment; 18. Biochar storage silo. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0018] Currently, existing equipment recovers waste heat from the high-temperature material at the rear of the reactor to preheat the low-temperature feed at the front, aiming to improve heat utilization efficiency. However, this method suffers from insufficient preheating of the feed, resulting in a material temperature entering the reactor system that is too low to reach the reaction temperature. This necessitates extending the residence time within the reactor to further heat it, thus reducing reaction efficiency and reactor utilization. Furthermore, the lack of waste heat recovery during system startup hinders material preheating, making system startup difficult. Therefore, this invention is proposed to achieve system preheating and recovery, thereby improving the reaction efficiency and utilization of the reactor.

[0019] See Figures 1-3This invention provides a continuous hydrothermal carbonization production system for high-moisture-content organic solid waste, comprising a heating oil furnace 1, a reaction vessel 8, a preheating device 14, a cooling device 15, and a solid-liquid separation device 17. The outlet of the preheating device 14 is connected to the inlet of the reaction vessel 8, the outlet of the reaction vessel 8 is connected to the inlet of the cooling device 15, and the outlet of the cooling device 15 is connected to the inlet of the solid-liquid separation device 17. The solid-liquid separation device 17 is used to separate biochar from the biochar slurry. The heat transfer oil in the heating oil furnace 1 reacts with the reaction vessel 8 on its outer wall via a heat transfer oil pump 16. The reactor heat transfer oil sleeve 9 is connected to the preheating section heat transfer oil pipe 5 of the preheating equipment 14 via a heat transfer oil pipe, and is used to preheat the high-moisture organic solid waste in the preheating equipment 14. The preheating section heat transfer oil pipe 5 is connected to the cooling section heat transfer oil pipe 11 of the cooling equipment 15 via a heat transfer oil pipe. The heat transfer oil in the cooling section heat transfer oil pipe 11 can absorb the heat of the biochar slurry in the cooling equipment 15. The cooling section heat transfer oil pipe 11 is connected to the heating oil furnace 1 via a heat transfer oil pipe. This scheme can realize waste heat recovery and reuse, reduce energy consumption, and improve production efficiency and output.

[0020] As a preferred structure, such as Figure 1 As shown, the reaction vessel 8 includes a horizontal tank and a stirrer 7. The stirrer 7 includes a motor and a horizontally placed stirring shaft. The motor is located on the outside of the tank and connected to the end of the stirring shaft. The stirring shaft has several radially arranged stirring blades spaced apart. This structure can stir the reactants, ensuring sufficient heat exchange between the reactants and the heat transfer oil, thus improving reaction efficiency.

[0021] In one specific embodiment of the present invention, such as Figure 1 As shown, the outlet of the cooling device 15 is connected to the biochar slurry storage chamber 13 via a pressure relief pump 12, where the biochar slurry is cooled to room temperature. The outlet of the biochar slurry storage chamber 13 is connected to the inlet of the solid-liquid separation device 17, and the solid outlet of the solid-liquid separation device 17 is connected to the biochar storage chamber 18 for convenient transfer. The drying equipment can also be used to dry the separated biochar solids.

[0022] To facilitate feeding, an organic solid waste buffer bin 2 is installed at the feed end of the preheating device 14 to buffer the organic solid waste. In use, the feed inlet of the preheating device 14 is connected to the organic solid waste buffer bin 2 via a booster pump 3. The direction of organic solid waste transport in the preheating device 14 is opposite to the flow direction of the heat transfer oil in the preheating section heat transfer oil pipe 5; the direction of biochar slurry transport in the cooling device 15 is opposite to the flow direction of the heat transfer oil in the cooling section heat transfer oil pipe 11. In this embodiment, both the preheating device 14 and the cooling device 15 adopt an inner and outer pipe structure. The material is transported in the inner pipe, and the heat transfer oil flows in the preheating section heat transfer oil pipe 5 and the cooling section heat transfer oil pipe 11, which serve as the outer pipes. This structure accelerates the heat exchange between the heat transfer oil and the organic solid waste and biochar slurry. This change saved production time and thus improved production efficiency.

[0023] In practical applications, the heating oil furnace, the heat transfer oil sleeve of the reaction vessel, the heat transfer oil pipe of the preheating section, the heat transfer oil pipe of the cooling section, and the heating oil furnace are sequentially connected to form a closed-loop heat transfer oil circulation circuit through heat transfer oil pipes. The heat transfer oil transmission process is as follows: (1) The heat transfer oil is heated in the heating oil furnace 1, and the heating temperature of the heat transfer oil is 180-230℃.

[0024] (2) The heated heat transfer oil is pumped by heat transfer oil pump 16 to the heat transfer oil sleeve 9 of the reactor 8 to maintain the reaction temperature of the reactor 8. The reaction temperature of the reactant 6 in the reactor 8 is 160-210℃ and the residence time of the reactant is 0.5-3h.

[0025] (3) After passing through the reactor 8, the heat transfer oil enters the heat transfer oil pipe 5 of the preheating section of the material preheating equipment 14. After the organic solid waste exchanges heat with the heat transfer oil in the heat transfer oil pipe 5 of the preheating section in the preheating equipment 14, the organic solid waste is transferred from low temperature to high temperature during the internal pipe of the preheating equipment 14 and enters the reactor 8. The heat transfer oil is transferred in the reverse direction in the heat transfer oil pipe 5 of the preheating section, from high temperature to low temperature. The input temperature of the heat transfer oil flowing from the heat transfer oil sleeve 9 of the reactor into the preheating equipment 14 is 180-230℃, and the output temperature is 60-100℃; the input temperature of the organic solid waste is 20-40℃, and the output temperature of the organic solid waste after heat exchange with the heat transfer oil is 160-210℃. The residence time of the organic solid waste is 0.5-2h.

[0026] (4) The heat transfer oil re-enters the cooling equipment 15. The biochar slurry discharged from the reactor is transferred from a high temperature to a low temperature during the transfer process in the inner pipe of the cooling equipment 15. The heat transfer oil is transferred in the reverse direction in the heat transfer oil pipe 11 of the cooling section, and rises from a low temperature to a high temperature. The input temperature of the heat transfer oil in the cooling equipment 15 is 60-100℃, the output temperature of the heat transfer oil is 140-190℃, the input temperature of the biochar slurry is 160-210℃, the output temperature is 80-120℃, and the residence time of the biochar slurry is 0.5-2h.

[0027] (5) After the heat transfer oil is output from the cooling equipment 15, it enters the heating oil furnace 1 for heating and circulation. After the biochar slurry is cooled by the heat transfer oil to recover heat, it is further cooled to room temperature by condensate water and then dehydrated and dried by the solid-liquid separation equipment 17 before being transported for disposal.

[0028] This invention is applicable to the hydrothermal carbonization treatment of organic solid waste with high water content, such as dehydrated sludge, plant straw, or livestock and poultry manure.

[0029] The following are application examples of several specific embodiments: Take sludge as an example of organic solid waste to be treated.

[0030] Sludge: Dewatered sludge from a sewage treatment plant in Chuzhou. Two types of sludge were selected, with moisture contents of 90% and 80% respectively. Sulfuric acid: National Pharmaceutical Reagent.

[0031] Example 1 Dewatered sludge with a moisture content of 90% from a sewage treatment plant in Chuzhou was mixed with concentrated sulfuric acid at a ratio of 5g / 100g DS (dry sludge weight) and pumped into a hydrothermal carbonization production system, which mainly consists of a heating oil furnace, a reaction vessel, preheating equipment, and cooling equipment.

[0032] The material is transported in the following direction: preheating equipment - reaction vessel - cooling equipment, and is heated by an oil heater.

[0033] According to the transfer sequence of heat transfer oil and materials: (1) The heat transfer oil is heated to 200°C in a heating oil furnace using natural gas; (2) Heating heat transfer oil is delivered to the reactor through a heat transfer oil pump to maintain the reaction temperature of the reactor at 180℃; (3) After passing through the reactor, the heat transfer oil enters the preheating equipment. In the preheating equipment, the organic solid waste is transferred from room temperature to 180°C in the inner tube and then enters the reactor. The heat transfer oil is transferred in the opposite direction from 200°C to 60°C in the outer tube. (4) The heat transfer oil re-enters the cooling equipment. In the cooling equipment, the biochar slurry discharged from the reactor is cooled from 180°C to 80°C by the inner tube, while the heat transfer oil is transported in the opposite direction by the outer tube, and heated from 60°C to 160°C. (5) The heat transfer oil output from the cooling equipment is 160°C and enters the heating oil furnace to be heated to 200°C for recycling.

[0034] After the biochar slurry is cooled by the heat transfer oil in the cooling equipment to recover heat, it is further cooled to room temperature by condensate water, then dehydrated and dried before being transported for disposal.

[0035] Example 2 Use dewatered sludge with a moisture content of 80% instead of dewatered sludge with a moisture content of 90%. The amount of sulfuric acid added is 5g / 100gDS of the oven-dried sludge. Other treatment steps and process parameters are the same as in Example 1.

[0036] Example 3 Dewatered sludge with a moisture content of 80% from a sewage treatment plant in Chuzhou was mixed with concentrated sulfuric acid at a ratio of 10g / 100g DS (dry sludge weight) and pumped into a hydrothermal carbonization production system, which mainly consists of an oil furnace, a reaction vessel, preheating equipment, and cooling equipment.

[0037] The material is transported in the following direction: preheating equipment - reaction vessel - cooling equipment, with heating provided by an oil furnace.

[0038] According to the transfer sequence of heat transfer oil and materials: (1) The heat transfer oil is heated to 180°C in a heating oil furnace using natural gas; (2) Heating heat transfer oil is delivered to the reactor through a heat transfer oil pump to maintain the reaction temperature of the reactor at 160℃; (3) After passing through the reactor, the heat transfer oil enters the preheating equipment. In the preheating equipment, the organic solid waste is transferred from room temperature to 160°C in the inner tube and then enters the reactor. The heat transfer oil is transferred in the opposite direction from 180°C to 60°C in the outer tube. (4) The heat transfer oil then enters the cooling equipment. In the cooling equipment, the biochar slurry discharged from the reactor is cooled from 160°C to 80°C in the inner tube, and the heat transfer oil is transferred in the opposite direction in the outer tube, and heated from 60°C to 140°C. (5) The heat transfer oil output from the cooling equipment is 140°C and enters the heating oil furnace to be heated to 180°C for recycling.

[0039] After the biochar slurry is cooled by the heat transfer oil in the cooling equipment to recover heat, it is further cooled to room temperature by condensate water, then dehydrated and dried before being transported for disposal.

[0040] Example 4 Dewatered sludge with a moisture content of 80% from a sewage treatment plant in Chuzhou was mixed with concentrated sulfuric acid at a ratio of 10g / 100g DS (dry sludge weight) and pumped into a hydrothermal carbonization production system, which mainly consists of an oil furnace, a reaction vessel, preheating equipment, and cooling equipment.

[0041] The material is transported in the following direction: preheating equipment - reaction vessel - cooling equipment, and is heated by an oil heater.

[0042] According to the transfer sequence of heat transfer oil and materials: (1) The heat transfer oil is heated to 220°C in a heating oil furnace using natural gas; (2) Heating heat transfer oil is delivered to the reactor through a heat transfer oil pump to maintain the reaction temperature of the reactor at 200℃; (3) After passing through the reactor, the heat transfer oil enters the preheating equipment. In the preheating equipment, the organic solid waste is transferred from room temperature to 200°C in the inner tube and then enters the reactor. The heat transfer oil is transferred in the opposite direction from 220°C to 80°C in the outer tube. (4) The heat transfer oil re-enters the cooling equipment. In the cooling equipment, the biochar slurry discharged from the reactor is cooled from 200°C to 100°C in the inner tube, and the heat transfer oil is transferred in the opposite direction in the outer tube, from 80°C to 180°C. (5) The heat transfer oil output from the cooling equipment is 180°C and enters the heating oil furnace to be heated to 220°C for recycling.

[0043] After the biochar slurry is cooled by the heat transfer oil in the cooling equipment to recover heat, it is further cooled to room temperature by condensate water, then dehydrated and dried before being transported for disposal.

[0044] Comparative Example 1 Dewatered sludge with a moisture content of 80% from a wastewater treatment plant in Chuzhou was mixed with concentrated sulfuric acid at a ratio of 10g / 100g DS (dry sludge weight) and pumped into a hydrothermal carbonization system. The system mainly consists of an oil heater, a reaction vessel, preheating equipment, and a cooling and recovery system.

[0045] The material transfer direction is preheating equipment - reactor - cooling recovery system. The heating oil furnace supplies heat to the reactor, and the heat recovered from the cooling system is used for the material preheating equipment. That is, the heating oil furnace and reactor heating are connected by one heat transfer oil circulation loop; the cooling equipment and preheating equipment are connected by another heat transfer oil circulation loop. (1) The heat transfer oil is heated to 230°C in the heating oil furnace system using natural gas; (2) The heating heat transfer oil is pumped to the reactor to maintain the reaction temperature of the reactor at 180°C, and the heat transfer oil is returned to the heating oil furnace; (3) After passing through the reactor, the material output temperature is 180℃. It enters the back-end cooling equipment and is cooled by heat exchange through heat transfer oil. The transmission direction of the heat transfer oil is opposite to the transmission direction of the material. That is, the material is transferred from 180℃ to 80℃ and the heat transfer oil is transferred in the opposite direction from 60℃ to 160℃. (4) The heat transfer oil that recovers heat from the cooling equipment is pumped to the front-end material preheating equipment. In the preheating equipment, the material is heated from room temperature to 140°C in the inner tube and enters the reactor. The heat transfer oil is cooled from 160°C to 60°C in the outer tube and then circulates back to the cooling equipment. After undergoing the above-mentioned hydrothermal carbonization treatment, the material is further cooled to room temperature by condensate water, dehydrated and dried, and then transported for disposal.

[0046]

[0047] Remark × — Poor liquidity; ○ — Moderate liquidity; ◎ — Good liquidity Remark Calculated based on a sludge moisture content of 80% A comparison of the parameters in the above embodiments is shown in the table above. The embodiments of the present invention have 10-20% lower energy consumption than the comparative examples, and the sludge residence time in the hydrothermal carbonization system is shorter, resulting in increased production capacity. The main reason is that in embodiments 1-4, the sludge enters the hydrothermal carbonization reactor at a temperature reaching the set reaction temperature after passing through the preheating equipment, allowing for a sufficiently stable reaction within the reactor. Conversely, in the comparative examples, the sludge enters the reactor at a temperature lower than the set reaction temperature after preheating, requiring further heating within the reactor to reach the reaction temperature. This necessitates additional energy and space allocation within the reactor, reducing reaction efficiency.

[0048] In summary, the present invention has the following beneficial effects: 1. This invention utilizes the opposite direction of heat transfer oil transport to the direction of material transport to improve heat exchange efficiency; 2. This invention adopts a closed-loop heat transfer oil circulation circuit, with one heat transfer oil pump realizing the circulation of heat transfer oil. The structure is simple and the control is convenient. 3. This invention can ensure that the temperature of the material entering the reactor reaches the hydrothermal carbonization reaction temperature, and has high waste heat recovery efficiency, reducing the energy consumption of the system. 4. The reaction efficiency of the reactants in the reactor is high, the material residence time is shortened, and the utilization rate and production capacity of the reactor are improved. 5. The system can be started quickly using this invention; 6. The present invention can achieve the reduction, stabilization and harmless treatment of high water content organic solid waste, retain the organic matter and resources, facilitate end-of-pipe resource utilization and reduce carbon emissions.

[0049] Many specific details have been set forth in the foregoing description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed above.

Claims

1. A continuous production system for hydrothermal carbonization of high water content organic solid waste, characterized in that: The system includes a heating oil furnace, a reaction vessel, a preheating device, a cooling device, and a solid-liquid separation device. The outlet of the preheating device is connected to the inlet of the reaction vessel, the outlet of the reaction vessel is connected to the inlet of the cooling device, and the outlet of the cooling device is connected to the inlet of the solid-liquid separation device. The solid-liquid separation device is used to separate biochar from the biochar slurry. The heat transfer oil in the heating oil furnace is connected to the reaction vessel heat transfer oil sleeve on the outer wall of the reaction vessel via a heat transfer oil pump. The heat transfer oil in the reaction vessel heat transfer oil sleeve is connected to the preheating section heat transfer oil pipe on the outer wall of the preheating device via a heat transfer oil pipe, allowing heat exchange between the organic solid waste in the preheating device and the heat transfer oil. The preheating section heat transfer oil pipe is connected to the cooling section heat transfer oil pipe on the outer wall of the cooling device via a heat transfer oil pipe, allowing heat exchange between the biochar slurry in the cooling device and the heat transfer oil. The cooling section heat transfer oil pipe returns to the heating oil furnace via a heat transfer oil pipe. The feed inlet of the preheating equipment is connected to the organic solid waste buffer bin via a booster pump; The reactor includes a horizontal tank and a stirring mechanism. The stirring mechanism includes a motor and a horizontally placed stirring shaft. The motor is located on the outside of the tank and connected to the end of the stirring shaft. The stirring shaft has a number of radially arranged stirring blades spaced apart.

2. The continuous production system for hydrothermal carbonization of high water content organic solid waste according to claim 1, characterized in that: The outlet of the biochar slurry cooling system is connected to the biochar slurry storage tank via a pressure relief pump, and the biochar slurry is cooled to room temperature in the biochar slurry storage tank; the outlet of the biochar slurry storage tank is connected to the inlet of the solid-liquid separation equipment, and the solid outlet of the solid-liquid separation equipment is connected to the biochar storage tank.

3. The continuous production system for hydrothermal carbonization of high-moisture organic solid waste according to claim 1, characterized in that: The heating oil furnace, the heat transfer oil sleeve of the reaction vessel, the heat transfer oil pipe of the preheating section, the heat transfer oil pipe of the cooling section, and the heating oil furnace are sequentially connected to form a closed-loop heat transfer oil circulation circuit through heat transfer oil pipes. The heat transfer oil transmission process is as follows: (1) The heat transfer oil is heated in the heating oil furnace; (2) The heated heat transfer oil is pumped to the heat transfer oil sleeve of the reactor to maintain the reaction temperature inside the reactor. (3) After passing through the reactor, the heat transfer oil enters the heat transfer oil pipe of the preheating section of the preheating equipment. The organic solid waste is transported in the inner pipe of the preheating equipment from low temperature to high temperature and enters the reactor. The heat transfer oil is transported in the opposite direction from high temperature to low temperature in the heat transfer oil pipe of the preheating section outside the preheating equipment. (4) The heat transfer oil re-enters the heat transfer oil pipe of the cooling section of the cooling equipment. The biochar slurry discharged from the reactor is transported in the inner pipe of the cooling equipment from high temperature to low temperature. The heat transfer oil is transported in the opposite direction in the heat transfer oil pipe of the cooling section, from low temperature to high temperature. (5) After the heat transfer oil is output from the cooling equipment, it enters the heating oil furnace for heating and recycling. After the biochar slurry is cooled and the heat is recovered by the heat transfer oil, it is further cooled to room temperature in the biochar slurry storage chamber, and then dehydrated and dried by the solid-liquid separation equipment before being transported for disposal.

4. The continuous production system for hydrothermal carbonization of high-moisture-content organic solid waste according to claim 3, characterized in that: In step (1), the heating temperature of the heat transfer oil in the heating oil furnace is 180-230℃.

5. The continuous production system for hydrothermal carbonization of high-moisture organic solid waste according to claim 3, characterized in that: In step (2), the reaction temperature of the reactants in the reactor is 160-210℃, and the residence time of the reactants is 0.5-3h.

6. The continuous production system for hydrothermal carbonization of high-moisture organic solid waste according to claim 3, characterized in that: In step (3), the input temperature of the heat transfer oil in the preheating equipment is 180-230℃, the output temperature of the heat transfer oil is 60-100℃, the input temperature of the organic solid waste is 20-40℃, the output temperature is 160-210℃, and the residence time of the organic solid waste is 0.5-2h.

7. The continuous production system for hydrothermal carbonization of high-moisture organic solid waste according to claim 3, characterized in that: In step (4), the input temperature of the heat transfer oil in the cooling device is 60-100℃, the output temperature of the heat transfer oil is 140-190℃, the input temperature of the biochar slurry is 160-210℃, the output temperature is 80-120℃, and the residence time of the biochar slurry is 0.5-2h.

8. The continuous production system for hydrothermal carbonization of high-moisture organic solid waste according to any one of claims 1-7, characterized in that: The high-moisture organic solid waste is dehydrated sludge, plant straw, or livestock and poultry manure.

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