Kitchen garbage resourceful treatment device and method

Abstract

The invention belongs to the technical field of solid waste treatment, and discloses a kitchen garbage resourceful treatment device and method. The treatment device comprises a kitchen waste staged treatment unit, a deodorization unit, a heat supply unit, a flue gas treatment unit and a PLC (Programmable Logic Controller) automatic control unit. According to the characteristics of high oil content and high organic matter content of the kitchen garbage, swill oil is separated out through a physical method, then the water of the kitchen garbage is used as a catalyst and a reactant, a subcritical hydrothermal liquefaction reaction is conducted, bio-oil, a water-phase product and biochar are produced, the bio-oil can be used for refining biodiesel, and the biochar can be used for refining biodiesel. The water-phase product can be used for producing liquid water fertilizer, the biochar can be used for agriculture and fuel, harmless, recycling and high-value utilization of the kitchen garbage can be realized, the fertilizer is turned into wealth, potential environmental and health risks caused by improper treatment of the kitchen garbage are avoided, resource waste is reduced, and the environmental, economic and social benefits are remarkable.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste treatment, and in particular to a device and method for resource treatment of kitchen waste. Background Art

[0002] Kitchen waste refers to perishable organic waste generated in residents' daily life, food processing, catering services, and unit catering activities, mainly including fruit peels and vegetable leaves, leftovers, tea dregs, restaurant / canteen post-meal residues, expired ingredients, food processing waste, etc. With the increase of my country's urbanization rate, the expansion of the catering industry, and the change of consumption patterns, the amount of kitchen waste generated in my country has increased year by year. Kitchen waste has the characteristics of high water content (60-90%), high organic matter content (accounting for more than 80% of dry matter), rich in nutrients such as nitrogen and phosphorus, and easy to corrupt and stink. If not properly disposed of, it will cause serious environmental pollution, disease transmission and waste of resources.

[0003] For the disposal of kitchen waste, the mainstream technologies at home and abroad are aerobic composting, anaerobic consumption, black soldier fly breeding, and coordinated incineration power generation, but there are problems such as long disposal cycle, low technical maturity, large land area, poor environmental and economic benefits, and the need for government subsidies. There is an urgent need to develop an economical, efficient, safe, and environmentally friendly resource disposal technology. In recent years, a lot of research and exploration of kitchen waste resource disposal technology has been carried out at home and abroad. For example, the Chinese patent application with publication number CN115947624A discloses a system for preparing organic fertilizer based on kitchen waste, which is prepared by hydrolysis and adding chemical fertilizers; the Chinese patent application with publication number CN115971211A discloses a method and system for resource utilization of all components of kitchen waste based on thermal hydrolysis, which prepares bio-oil, leaf fertilizer, and soil conditioner through crushing and sorting, low-temperature thermal hydrolysis, high-temperature thermal hydrolysis, and blending; the Chinese patent application with publication number CN104148357A discloses a method and device for treating organic solid waste. However, none of the above solutions have achieved the maximum resource utilization of kitchen waste, the economic and environmental benefits are low, and the technical processes still need to be improved. Summary of the invention

[0004] The purpose of the present invention is to provide a kitchen waste resource processing device and method to solve the problems of existing kitchen waste treatment processes, such as long disposal cycle, low technical maturity, large device footprint, poor environmental and economic benefits, and failure to maximize resource utilization of kitchen waste.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a kitchen waste resource processing device, comprising a kitchen waste classification processing unit, a deodorization unit 8, a heating unit, a smoke treatment unit 21, and a PLC automatic control unit 26;

[0007] The kitchen waste classification treatment unit includes a factory waste storage tank 2, a kitchen waste sorting unit 5, a kitchen waste crushing and pulping unit 7, a primary slurry heating and storage unit 9, an oil-water-solid three-phase separation unit 11, a solid-water mixed secondary grinding unit 13, a secondary slurry heating and storage unit 14, a tertiary slurry reaction unit 15, a reaction product storage and separation unit 16, and an oil-solid storage unit 18, which are connected in sequence; the kitchen waste sorting unit 5 is also connected to a separation product storage unit 4; the oil-water-solid three-phase separation unit 11 is also connected to a swill oil storage unit 12; the reaction product storage and separation unit 16 is also connected to a liquid water fertilizer storage unit 17;

[0008] The enclosed room 1 includes the factory waste storage tank 2, the separation product storage unit 4, the kitchen waste sorting unit 5, and the kitchen waste crushing and pulping unit 7; the deodorization unit 8 is connected to the enclosed room 1;

[0009] The heating unit includes a biomass boiler 20 and a heat-conducting oil furnace 19 connected in sequence; the heat-conducting oil in the heat-conducting oil furnace 19 flows through the tertiary slurry reaction unit 15, the secondary slurry heating and storage unit 14, and the primary slurry heating and storage unit 9 in sequence in the heat-conducting oil heating pipe 22 and then returns to the heat-conducting oil furnace 19;

[0010] The flue gas treatment unit 21 is connected to the biomass boiler 20;

[0011] The PLC automatic control unit 26 is respectively connected to the kitchen waste sorting unit 5, the kitchen waste crushing and pulping unit 7, the primary slurry heating and storage unit 9, the oil-water-solid three-phase separation unit 11, the solid-water mixed secondary grinding unit 13, the secondary slurry heating and storage unit 14, the tertiary slurry reaction unit 15, the deodorization unit 8, and the flue gas treatment unit 21.

[0012] Preferably, in the kitchen waste resource treatment device, in the kitchen waste classification treatment unit, the factory waste storage tank 2 is connected to the kitchen waste sorting unit 5 through a valve 3; the oil-water-solid three-phase separation unit 11 is connected to the swill oil storage unit 12 through a valve; the reaction product storage and separation unit 16 is connected to the oil-solid storage unit 18 through a valve; the reaction product storage and separation unit 16 is connected to the liquid water fertilizer storage unit 17 through a valve.

[0013] Preferably, in the kitchen waste resource processing device, in the kitchen waste grading processing unit, the kitchen waste sorted out as separated materials in the kitchen waste sorting unit 5 is transported to the kitchen waste crushing and pulping unit 7 by a pump 6; the slurry of the kitchen waste crushing and pulping unit 7 is transported to the primary slurry heating and storage unit 9 by a pump; the kitchen waste primary slurry of the primary slurry heating and storage unit 9 is transported to the oil-water-solid three-phase separation unit 11 by a pump; the solid phase and the water phase separated by the oil-water-solid three-phase separation unit 11 are transported to the solid-water mixed secondary grinding unit 13 by a pump; the secondary grinding slurry of the solid-water mixed secondary grinding unit 13 is transported to the secondary slurry heating and storage unit 14 by a pump; the slurry of the secondary slurry heating and storage unit 14 is transported to the tertiary slurry reaction unit 15 by a pump; the reaction product of the tertiary slurry reaction unit 15 is transported to the reaction product storage and separation unit 16 by a pump.

[0014] Preferably, in the kitchen waste resource processing device, in the kitchen waste classification processing unit, a stirring device 10 - 1 and a heating device 25 - 3 are provided inside the primary slurry heating and storage unit 9 .

[0015] Preferably, in the kitchen waste resource processing device, in the kitchen waste classification processing unit, a stirring device 10 - 2 and a heating device 25 - 2 are provided inside the secondary slurry heating and storage unit 14 .

[0016] Preferably, in the kitchen waste resource processing device, in the kitchen waste classification processing unit, a stirring device 10 - 3 and a heating device 25 - 1 are provided inside the three-stage slurry reaction unit 15 .

[0017] The present invention also provides a method for recycling kitchen waste, which uses the kitchen waste recycling device and comprises the following steps:

[0018] Step 1, sorting the kitchen waste stored in the factory waste storage pool 2 through the kitchen waste sorting unit 5; transporting the sorted separated materials to the separated material storage unit 4; transporting the sorted separated kitchen waste to the kitchen waste crushing and pulping unit 7 for crushing, and transporting the crushed slurry to the primary slurry heating and storage unit 9; collecting the odor in the closed room 1, and treating the odor through the deodorization unit 8;

[0019] Step 2, the slurry in the primary slurry heating storage unit 9 is subjected to a first reaction; the kitchen waste primary slurry obtained by the first reaction is transported to the oil-water-solid three-phase separation unit 11 for separation to obtain swill oil, solid phase and water phase; the swill oil is transported to the swill oil storage unit 12; the solid phase and the water phase are mixed and transported to the solid-water mixed secondary grinding unit 13 for grinding to obtain secondary ground slurry; the secondary ground slurry is transported to the secondary slurry heating storage unit 14 for a second reaction; the slurry obtained by the second reaction is transported to the tertiary slurry reaction unit 15;

[0020] Step 3: The slurry in the tertiary slurry reaction unit 15 undergoes a third reaction to obtain a reaction product; the reaction product is transported to the reaction product storage and separation unit 16 for separation to obtain a water phase product 23 and an oil-solid mixed phase product 24; the water phase product 23 is transported to the liquid water fertilizer storage unit 17; the oil-solid mixed phase product 24 is transported to the oil-solid storage unit 18;

[0021] The heat generated by the biomass boiler 20 heats the thermal oil in the thermal oil furnace 19 to provide heat for the first reaction and the second reaction in step 2 and the third reaction in step 3; the flue gas in the biomass boiler 20 is collected and treated by the flue gas treatment unit 21.

[0022] Preferably, in the method for resource processing of kitchen waste, in step 2, the conditions of the first reaction include: pressure is normal pressure, heating temperature is 80-100°C, stirring speed is 100-600rpm, and reaction time is 0.5-2h.

[0023] Preferably, in the method for resource processing of kitchen waste, in step 2, the conditions of the second reaction include: pressure of 0.1 to 1 MPa, heating temperature of 100 to 180°C, stirring speed of 100 to 600 rpm, and reaction time of 0.5 to 2 h.

[0024] Preferably, in the method for resource processing of kitchen waste, in step 3, the conditions of the third reaction include: pressure of 5 to 15 MPa, reaction temperature of 260 to 350°C, stirring speed of 100 to 600 rpm, and reaction time of 0.5 to 2 h.

[0025] It can be seen from the above technical solution that compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The method for recycling kitchen waste provided by the present invention has a short reaction time and a fast processing speed, and the reaction can be completed in 0.5 to 2 hours. At the same time, the technical process occupies a small area, which is only 1 / 10 of the area occupied by other technologies with the same tonnage.

[0027] (2) The method for resource recovery of kitchen waste provided by the present invention is completely harmless. Since the reaction is carried out under medium temperature (260-350°C) and high pressure (5-15MPa) conditions, viruses and bacteria are completely inactivated, ensuring product safety and hygiene.

[0028] (3) The method for recycling kitchen waste provided by the present invention does not require dehydration and has low energy consumption. The water in the kitchen waste is the catalyst and reactant required for the reaction. Therefore, there is no need for drying and dehydration like other processes, and the overall process has low energy consumption.

[0029] (4) The method for resource-based treatment of kitchen waste provided by the present invention increases the degree of resource utilization of kitchen waste, realizes 100% resource utilization of kitchen waste, produces high-value products such as swill oil, bio-oil, biochar, liquid water-soluble fertilizer, etc., and turns fertilizer into treasure.

[0030] (5) The kitchen waste resource processing device provided by the present invention is clean and tidy in environment, and the production is fully enclosed. The kitchen waste storage and sorting processes are separately enclosed. Since the raw materials and products of other processes are in pipelines or reaction containers, there is no odor in the factory area and workshop, and no high-frequency noise is generated. The entire production process does not generate wastewater, and the sorted separation waste residues are recycled or landfilled. The entire process is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the description of the embodiments or the prior art are briefly introduced below.

[0032] Figure 1 It is a structural schematic diagram of a kitchen waste resource processing device;

[0033] Figure 2 It is a flow chart of the method for recycling kitchen waste;

[0034] Among them, 1-enclosed room, 2-factory garbage storage tank, 3-valve, 4-separator storage unit, 5-kitchen waste sorting unit, 6-pump, 7-kitchen waste crushing and pulping unit, 8-deodorization unit, 9-primary slurry heating and storage unit, 10-stirring device (including 10-1, 10-2, 10-3), 11-oil-water-solid three-phase separation unit, 12-swill oil storage unit, 13-solid-water mixed secondary grinding unit, 14-secondary slurry heating and storage unit, 15-tertiary slurry reaction unit, 16-reaction product storage and separation unit, 17-liquid water fertilizer storage unit, 18-oil-solid storage unit, 19-thermal oil furnace, 20-biomass boiler, 21-flue gas treatment unit, 22-thermal oil heating pipe, 23-water phase product, 24-oil-solid mixed phase product, 25-heating device (including 25-1, 25-2, 25-3), 26-PLC automatic control unit. Detailed implementation mode

[0035] The present invention provides a kitchen waste resource treatment device, which includes a kitchen waste classification treatment unit, a deodorization unit 8, a heat supply unit, a flue gas treatment unit 21, and a PLC automatic control unit 26;

[0036] The kitchen waste classification treatment unit includes a factory waste storage tank 2, a kitchen waste sorting unit 5, a kitchen waste crushing and pulping unit 7, a primary slurry heating and storage unit 9, an oil-water-solid three-phase separation unit 11, a solid-water mixed secondary grinding unit 13, a secondary slurry heating and storage unit 14, a tertiary slurry reaction unit 15, a reaction product storage and separation unit 16, and an oil-solid storage unit 18; the kitchen waste sorting unit 5 is also connected with a separation product storage unit 4; the oil-water-solid three-phase separation unit 11 is also connected with a swill oil storage unit 12; the reaction product storage and separation unit 16 is also connected with a liquid water fertilizer storage unit 17;

[0037] The closed room 1 includes the factory waste storage tank 2, the separation product storage unit 4, the kitchen waste sorting unit 5, and the kitchen waste crushing and pulping unit 7; the deodorization unit 8 is connected with the closed room 1;

[0038] The heat supply unit includes a biomass boiler 20 and a heat-conducting oil furnace 19 connected in sequence; the heat-conducting oil in the heat-conducting oil furnace 19 flows through the tertiary slurry reaction unit 15, the secondary slurry heating and storage unit 14, and the primary slurry heating and storage unit 9 in sequence in the heat-conducting oil heating pipe 22 and then returns to the heat-conducting oil furnace 19;

[0039] The flue gas treatment unit 21 is connected with the biomass boiler 20;

[0040] The PLC automatic control unit 26 is respectively connected with the kitchen waste sorting unit 5, the kitchen waste crushing and pulping unit 7, the primary slurry heating and storage unit 9, the oil-water-solid three-phase separation unit 11, the solid-water mixed secondary grinding unit 13, the secondary slurry heating and storage unit 14, the tertiary slurry reaction unit 15, the deodorization unit 8, and the flue gas treatment unit 21.

[0041] In the present invention, in the kitchen waste classification treatment unit, the factory waste storage tank 2 is connected with the kitchen waste sorting unit 5 through a valve 3; the oil-water-solid three-phase separation unit 11 is connected with the swill oil storage unit 12 through a valve; the reaction product storage and separation unit 16 is connected with the oil-solid storage unit 18 through a valve; the reaction product storage and separation unit 16 is connected with the liquid water fertilizer storage unit 17 through a valve.

[0042] In the present invention, in the kitchen waste grading treatment unit, the kitchen waste sorted out as separated materials in the kitchen waste sorting unit 5 is transported to the kitchen waste crushing and pulping unit 7 by a pump 6; the slurry of the kitchen waste crushing and pulping unit 7 is transported to the primary slurry heating and storage unit 9 by a pump; the kitchen waste primary slurry of the primary slurry heating and storage unit 9 is transported to the oil-water-solid three-phase separation unit 11 by a pump; the solid phase and the water phase separated by the oil-water-solid three-phase separation unit 11 are transported to the solid-water mixed secondary grinding unit 13 by a pump; the secondary grinding slurry of the solid-water mixed secondary grinding unit 13 is transported to the secondary slurry heating and storage unit 14 by a pump; the slurry of the secondary slurry heating and storage unit 14 is transported to the tertiary slurry reaction unit 15 by a pump; the reaction product of the tertiary slurry reaction unit 15 is transported to the reaction product storage and separation unit 16 by a pump.

[0043] In the present invention, in the kitchen waste classification processing unit, a stirring device 10-1 and a heating device 25-3 are provided inside the primary slurry heating storage unit 9. The heating method of the primary slurry heating storage unit 9 is heat transfer by heat transfer oil supplemented by electric heating.

[0044] In the present invention, in the kitchen waste classification processing unit, a stirring device 10-2 and a heating device 25-2 are provided inside the secondary slurry heating storage unit 14. The heating method of the secondary slurry heating storage unit 14 is heat transfer by heat transfer oil supplemented by electric heating.

[0045] In the present invention, in the kitchen waste classification processing unit, a stirring device 10-3 and a heating device 25-1 are provided inside the three-stage slurry reaction unit 15. The heating method of the three-stage slurry reaction unit 15 is heat transfer by heat transfer oil supplemented by electric heating.

[0046] In the present invention, in the heating unit, the heat-conducting oil in the heat-conducting oil furnace 19 transfers heat by flowing in the heat-conducting oil heating pipe 22; at the same time, the heat-conducting oil flows through the tertiary slurry reaction unit 15, the secondary slurry heating storage unit 14, and the primary slurry heating storage unit 9 in sequence, providing heat for the above-mentioned units, heating the reaction products, and the heating process realizes the cascade utilization of energy.

[0047] In the present invention, the PLC automatic control unit 26 controls the operation of the connected kitchen waste sorting unit 5, the kitchen waste crushing and pulping unit 7, the primary slurry heating and storage unit 9, the oil-water-solid three-phase separation unit 11, the solid-water mixed secondary grinding unit 13, the secondary slurry heating and storage unit 14, the tertiary slurry reaction unit 15, the deodorization unit 8, and the flue gas treatment unit 21.

[0048] The present invention also provides a method for recycling kitchen waste, which uses the kitchen waste recycling device and comprises the following steps:

[0049] Step 1, sorting the kitchen waste stored in the factory waste storage pool 2 through the kitchen waste sorting unit 5; transporting the sorted separated materials to the separated material storage unit 4; transporting the sorted separated kitchen waste to the kitchen waste crushing and pulping unit 7 for crushing, and transporting the crushed slurry to the primary slurry heating and storage unit 9; collecting the odor in the closed room 1, and treating the odor through the deodorization unit 8;

[0050] Step 2, the slurry in the primary slurry heating storage unit 9 is subjected to a first reaction; the kitchen waste primary slurry obtained by the first reaction is transported to the oil-water-solid three-phase separation unit 11 for separation to obtain swill oil, solid phase and water phase; the swill oil is transported to the swill oil storage unit 12; the solid phase and the water phase are mixed and transported to the solid-water mixed secondary grinding unit 13 for grinding to obtain secondary ground slurry; the secondary ground slurry is transported to the secondary slurry heating storage unit 14 for a second reaction; the slurry obtained by the second reaction is transported to the tertiary slurry reaction unit 15;

[0051] Step 3: The slurry in the tertiary slurry reaction unit 15 undergoes a third reaction to obtain a reaction product; the reaction product is transported to the reaction product storage and separation unit 16 for separation to obtain a water phase product 23 and an oil-solid mixed phase product 24; the water phase product 23 is transported to the liquid water fertilizer storage unit 17; the oil-solid mixed phase product 24 is transported to the oil-solid storage unit 18;

[0052] The heat generated by the biomass boiler 20 heats the thermal oil in the thermal oil furnace 19 to provide heat for the first reaction and the second reaction in step 2 and the third reaction in step 3; the flue gas in the biomass boiler 20 is collected and treated by the flue gas treatment unit 21.

[0053] In the present invention, the kitchen waste comes from a kitchen waste collection and transportation unit, and the kitchen waste includes but is not limited to restaurant kitchen waste, household kitchen waste, and waste from fruit and vegetable and fresh food markets.

[0054] In the present invention, in step 1, the sorted separated materials include but are not limited to plastics, metals, ceramics, chopsticks, sand and gravel; ceramics, sand and gravel are landfilled, and chopsticks, metals, plastics, etc. are recycled.

[0055] In the present invention, in step 1, the micro-negative pressure of the closed room 1 is set to -5 to -20 Pa (further preferably -8 to -15 Pa, and more preferably -10 Pa), so that the collected odor enters the deodorization unit 8 and is discharged in compliance with the standards after being treated by the deodorization unit 8.

[0056] In the present invention, in step 1, the kitchen waste crushing and pulping unit 7 crushes the kitchen waste sorted out as the separated material into a slurry with a particle size of ≤1 mm.

[0057] In the present invention, in step 2, the conditions of the first reaction include: the pressure is preferably normal pressure; the heating temperature is preferably 80-100°C, more preferably 80-90°C, more preferably 80°C; the stirring speed is preferably 100-600rpm, more preferably 300-500rpm, more preferably 300rpm; the reaction time is preferably 0.5-2h, more preferably 0.5-1h, more preferably 0.5h.

[0058] In the present invention, in step 2, the swill oil in the swill oil storage unit 12 is used to prepare biodiesel.

[0059] In the present invention, in step 2, the particle size of the secondary grinding slurry is ≤76 μm.

[0060] In the present invention, in step 2, the conditions of the second reaction include: the pressure is preferably 0.1-1 MPa, more preferably 0.1-0.5 MPa, and more preferably 0.1 MPa; the heating temperature is preferably 100-180°C, more preferably 120-160°C, and more preferably 160°C; the stirring speed is preferably 100-600 rpm, more preferably 300-500 rpm, and more preferably 300 rpm; the reaction time is preferably 0.5-2 h, more preferably 0.5-1 h, and more preferably 0.5 h.

[0061] In the present invention, in step 3, the conditions of the third reaction include: the pressure is preferably 5-15 MPa, more preferably 8-12 MPa, and more preferably 10 MPa; the reaction temperature is preferably 260-350°C, more preferably 280-320°C, and more preferably 300°C; the stirring speed is preferably 100-600 rpm, more preferably 200-400 rpm, and more preferably 200 rpm; the reaction time is preferably 0.5-2 h, more preferably 0.8-1.5 h, and more preferably 1 h.

[0062] In the present invention, in step 3, after the third reaction is completed, it also includes: depressurization and cooling, and the specific process includes: when the temperature of the tertiary slurry reaction unit 15 is reduced to ≤150°C, the exhaust valve is opened to release the pressure and the pressure is reduced to normal pressure.

[0063] In the present invention, in step 3, the water phase product 23 in the liquid water fertilizer storage unit 17 is used to prepare liquid fertilizer.

[0064] In the present invention, in step 3, the oil-solid mixed phase product 24 in the oil-solid storage unit 18 is utilized in a high-value manner.

[0065] In the present invention, the flue gas generated by the biomass boiler 20 is collected and introduced into the flue gas treatment unit 21 for purification before being discharged in compliance with emission standards.

[0066] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] Example 1

[0068] This embodiment provides a method for recycling kitchen waste. Figure 1 The kitchen waste resource processing device includes the following steps, and the flow chart is as follows Figure 2 As shown:

[0069] Step 1, transporting kitchen waste (organic matter composition on a dry basis: 65wt% carbohydrates (including 15wt% cellulose), 20wt% protein, 15wt% lipids, including meat residues, expired bread, fruit peels, bones, condiment residues (star anise, cinnamon, etc.), vegetable stems and leaves, etc.; physical properties: moisture content 80wt%) to a resource disposal plant through a kitchen waste collection and transportation unit, storing it in a factory waste storage pool, opening a valve and sending it to a kitchen waste sorting unit for sorting; the sorted separated materials (plastics, metals, ceramics, chopsticks, sand and gravel) are transported to a separated material storage unit, and then further separated, ceramics and sand and gravel are finally landfilled, and chopsticks, metals, and plastics are recycled; the kitchen waste from which the separated materials are sorted is pumped to a kitchen waste crushing and pulping unit for crushing to obtain a slurry with a particle size of ≤1mm; the crushed slurry is pumped to a primary slurry heating and storage unit; at the same time, the closed room is set to a slightly negative pressure (pressure value -10Pa) so that the collected odor enters a deodorization unit and is discharged after being treated to meet the emission standards;

[0070] Step 2, the slurry in the primary slurry heating storage unit is reacted at normal pressure, temperature 80°C (heat transfer by heat transfer oil assisted by electric heating), and stirring speed 300rpm for 0.5h; the kitchen waste primary slurry obtained by the reaction is pumped to the oil-water-solid three-phase separation unit for separation to obtain swill oil, solid phase, and water phase; the valve is opened to transport the swill oil to the swill oil storage unit for the preparation of biodiesel; the solid phase and the water phase are mixed and pumped to the solid-water mixed secondary grinding unit for grinding to obtain a secondary grinding slurry with a particle size of ≤76μm; the secondary grinding slurry is pumped to the secondary slurry heating storage unit, reacted at a pressure of 0.1MPa, a temperature of 160°C (heat transfer by heat transfer oil assisted by electric heating), and a stirring speed of 300rpm for 0.5h, and the slurry obtained by the reaction is pumped to the tertiary slurry reaction unit;

[0071] Step 3: The slurry in the tertiary slurry reaction unit reacts for 1 h under a pressure of 10 MPa, a temperature of 300 °C (heat transfer by heat-conducting oil supplemented by electric heating), and a stirring speed of 200 rpm to obtain a reaction product; after the reaction, the pressure is reduced and cooled. When the temperature of the tertiary slurry reaction unit drops to ≤150 °C, the exhaust valve is opened to relieve pressure, and the pressure is reduced to atmospheric pressure. The reaction product is pumped to the reaction product storage and separation unit for separation to obtain an aqueous phase product and an oil-solid mixed phase product; the valve is opened, and the aqueous phase product is transported to the liquid water fertilizer storage unit for the preparation of liquid fertilizer; the valve is opened, and the oil-solid mixed phase product is transported to the oil-solid storage unit for high-value utilization (the heat for heat transfer by heat-conducting oil comes from the combustion of biomass particles in a biomass boiler, and then flue gas is generated; the flue gas in the biomass boiler is collected and treated by a flue gas treatment unit, and after purification, it is discharged up to standard).

[0072] In Step 2, the yield of swill oil is 5% of the weight of the primary kitchen waste slurry. Its main component is triglyceride (accounting for 95 wt% in swill oil), and it contains a small amount (accounting for 5 wt% in swill oil) of substances such as aldehydes, ketones, lactones, and peroxides.

[0073] In Step 3, the yield of the aqueous phase product is 75% of the weight of the primary kitchen waste slurry. Its main components are dissolved organic carbon (content 40 g / L), total nutrients of N+P2O5+K2O (content 6 g / L), and trace elements Zn, Mg, Ca, Fe, Cu, etc. (content 5 g / L).

[0074] In Step 3, the oil-solid mixed phase product is mainly composed of bio-oil and biochar. Among them, the yield of bio-oil is 12% of the weight of the primary kitchen waste slurry. Bio-oil mainly contains 50 wt% alkanes, 25 wt% cycloalkanes, 15 wt% aromatic hydrocarbons, and 10 wt% non-hydrocarbon compounds; the yield of biochar is 3% of the weight of the primary kitchen waste slurry.

[0075] In summary, the device and method for the comprehensive resource utilization of kitchen waste developed by the present invention, according to the characteristics of high oil content and high organic matter content of kitchen waste, after separating swill oil by a physical method, uses the moisture in the kitchen waste as a catalyst and reactant to carry out subcritical hydrothermal liquefaction reaction to produce bio-oil, aqueous phase product, and biochar. Among them, bio-oil can be used to extract biodiesel, the aqueous phase product can be used to produce liquid water fertilizer, and biochar can be used for agricultural and fuel purposes. It can realize the harmless, resource-based, and high-value utilization of kitchen waste, produce high-value products such as swill oil, bio-oil, biochar, and liquid water-soluble fertilizer, turn waste into treasure, avoid potential environmental and health risks caused by improper disposal of kitchen waste, reduce resource waste, and have significant environmental, economic, and social benefits. It is an economic, efficient, and environmentally friendly solution.

[0076] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A kitchen waste resource processing device, characterized in that: It comprises a kitchen waste classification processing unit, a deodorization unit (8), a heating unit, a smoke treatment unit (21), and a PLC automatic control unit (26); The kitchen waste classification treatment unit comprises a factory waste storage pool (2), a kitchen waste sorting unit (5), a kitchen waste crushing and pulping unit (7), a primary slurry heating and storage unit (9), an oil-water-solid three-phase separation unit (11), a solid-water mixed secondary grinding unit (13), a secondary slurry heating and storage unit (14), a tertiary slurry reaction unit (15), a reaction product storage and separation unit (16), and an oil-solid storage unit (18) which are connected in sequence; the kitchen waste sorting unit (5) is also connected to a separator storage unit (4); the oil-water-solid three-phase separation unit (11) is also connected to a swill oil storage unit (12); and the reaction product storage and separation unit (16) is also connected to a liquid water fertilizer storage unit (17); The enclosed room (1) comprises the factory waste storage pool (2), the separated material storage unit (4), the kitchen waste sorting unit (5), and the kitchen waste crushing and pulping unit (7); the deodorizing unit (8) is connected to the enclosed room (1); The heating unit comprises a biomass boiler (20) and a thermal oil furnace (19) connected in sequence; the thermal oil in the thermal oil furnace (19) flows in sequence through the tertiary slurry reaction unit (15), the secondary slurry heating storage unit (14), and the primary slurry heating storage unit (9) in a thermal oil heating pipe (22) and flows back to the thermal oil furnace (19); The flue gas treatment unit (21) is connected to the biomass boiler (20); The PLC automatic control unit (26) is respectively connected to the kitchen waste sorting unit (5), the kitchen waste crushing and pulping unit (7), the primary slurry heating and storage unit (9), the oil-water-solid three-phase separation unit (11), the solid-water mixed secondary grinding unit (13), the secondary slurry heating and storage unit (14), the tertiary slurry reaction unit (15), the deodorization unit (8), and the flue gas treatment unit (21).

2. A kitchen waste resource processing unit according to claim 1, characterized in that: In the kitchen waste classification processing unit, the factory waste storage tank (2) is connected to the kitchen waste sorting unit (5) via a valve (3); the oil-water-solid three-phase separation unit (11) is connected to the swill oil storage unit (12) via a valve; the reaction product storage and separation unit (16) is connected to the oil-solid storage unit (18) via a valve; and the reaction product storage and separation unit (16) is connected to the liquid water fertilizer storage unit (17) via a valve.

3. The kitchen waste resource processing device according to claim 1, characterized in that: In the kitchen waste classification processing unit, the kitchen waste separated from the kitchen waste sorting unit (5) is transported to the kitchen waste crushing and pulping unit (7) through a pump (6); the slurry of the kitchen waste crushing and pulping unit (7) is transported to the primary slurry heating and storage unit (9) through a pump; the kitchen waste primary slurry of the primary slurry heating and storage unit (9) is transported to the oil-water-solid three-phase separation unit (11) through a pump; the solid phase and the water phase separated by the oil-water-solid three-phase separation unit (11) are transported to the solid-water mixed secondary grinding unit (13) through a pump; the secondary grinding slurry of the solid-water mixed secondary grinding unit (13) is transported to the secondary slurry heating and storage unit (14) through a pump; the slurry of the secondary slurry heating and storage unit (14) is transported to the tertiary slurry reaction unit (15) through a pump; and the reaction product of the tertiary slurry reaction unit (15) is transported to the reaction product storage and separation unit (16) through a pump.

4. The kitchen waste resource processing device according to claim 1, characterized in that: In the kitchen waste classification processing unit, a stirring device (10-1) and a heating device (25-3) are provided inside the primary slurry heating and storage unit (9).

5. The kitchen waste resource processing device according to claim 1, characterized in that: In the kitchen waste classification processing unit, a stirring device (10-2) and a heating device (25-2) are provided inside the secondary slurry heating and storage unit (14).

6. The kitchen waste resource processing device according to claim 1, characterized in that: In the kitchen waste classification processing unit, a stirring device (10-3) and a heating device (25-1) are provided inside the three-stage slurry reaction unit (15).

7. A method for recycling kitchen waste, characterized in that: The kitchen waste resource processing device according to any one of claims 1 to 6 comprises the following steps: Step 1, sorting the kitchen waste stored in the factory waste storage pool (2) through a kitchen waste sorting unit (5); transporting the sorted separated materials to a separated material storage unit (4); transporting the sorted separated kitchen waste to a kitchen waste crushing and pulping unit (7) for crushing, and transporting the crushed slurry to a primary slurry heating and storage unit (9); collecting odor in the closed room (1), and treating the odor through a deodorization unit (8); Step 2, the slurry in the primary slurry heating storage unit (9) undergoes a first reaction; the kitchen waste primary slurry obtained by the first reaction is transported to the oil-water-solid three-phase separation unit (11) for separation to obtain swill oil, solid phase and water phase; the swill oil is transported to the swill oil storage unit (12); the solid phase and the water phase are mixed and transported to the solid-water mixed secondary grinding unit (13) for grinding to obtain secondary ground slurry; the secondary ground slurry is transported to the secondary slurry heating storage unit (14) for a second reaction; the slurry obtained by the second reaction is transported to the tertiary slurry reaction unit (15); Step 3: The slurry in the tertiary slurry reaction unit (15) undergoes a third reaction to obtain a reaction product; the reaction product is transported to the reaction product storage and separation unit (16) for separation to obtain a water phase product (23) and an oil-solid mixed phase product (24); the water phase product (23) is transported to the liquid water fertilizer storage unit (17); and the oil-solid mixed phase product (24) is transported to the oil-solid storage unit (18); The heat generated by the biomass boiler (20) heats the heat transfer oil in the heat transfer oil furnace (19), thereby providing heat for the first reaction and the second reaction in step 2 and the third reaction in step 3; the flue gas in the biomass boiler (20) is collected and treated by the flue gas treatment unit (21).

8. The method for recycling kitchen waste according to claim 7, characterized in that: In step 2, the conditions of the first reaction include: pressure is normal pressure, heating temperature is 80-100° C., stirring speed is 100-600 rpm, and reaction time is 0.5-2 h.

9. The method for recycling kitchen waste according to claim 7, characterized in that: In step 2, the conditions of the second reaction include: pressure of 0.1-1 MPa, heating temperature of 100-180° C., stirring speed of 100-600 rpm, and reaction time of 0.5-2 h.

10. The method for recycling kitchen waste according to claim 7, characterized in that: In step 3, the conditions of the third reaction include: pressure of 5 to 15 MPa, reaction temperature of 260 to 350° C., stirring speed of 100 to 600 rpm, and reaction time of 0.5 to 2 h.

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