A subcritical water treatment device for medical waste and its treatment method

Abstract

The present invention discloses a method for treating medical waste by subcritical water treatment, comprising the following steps: S1. Mixing and pressurizing: Mix medical waste and crop waste and put them into a number of reaction tanks, and continuously pressurize the number of reaction tanks at the same time; S2. Intermittent depressurization: First, instantaneously depressurize a single tank body, then instantaneously depressurize adjacent tank bodies, and at the same time open the connecting plates between adjacent tank bodies to allow the air pressure and oscillation energy to flow until all tank bodies are depressurized; S3. Preliminary pressurization: Adjust the moisture content of the tank bodies in S2, close all valves and send in steam for heating and pressurization; S4. Continuous pressurization: Form a thermal cycle through an organic heat carrier and a heating sleeve, and at the same time continue to heat and pressurize; S5. Product collection: Discharge the remaining water vapor and heat in the tank body and collect the products in the tank body. By designing intermittent pressurization and then depressurization, the present invention enables the substances in the reaction tank to form an explosion and fragmentation effect, making the fibers convenient for subsequent cracking reactions.

Description

Technical Field

[0001] The present invention relates to the technical field of medical waste treatment, and in particular to a subcritical water treatment device for medical waste and a treatment method thereof. Background Art

[0002] Medical waste refers to the waste generated by medical and health institutions in medical treatment, prevention, health care and other related activities, which has direct or indirect infectivity, toxicity and other hazards. It may contain a large number of pathogenic microorganisms and harmful chemical substances, and even radioactive and damaging substances. Therefore, medical waste is an important risk factor for disease transmission or related public health problems. Medical waste can be divided into pathological waste, sharp waste, pharmaceutical waste, chemical waste and infectious waste. Among them, infectious waste refers to medical waste carrying pathogenic microorganisms and having the risk of spreading infectious diseases, including items contaminated by patients' blood, body fluids, excreta, and medical waste plastics such as garbage generated by infectious disease patients.

[0003] At present, the treatment technologies for medical waste include high-temperature incineration (pyrolysis incineration), chemical disinfection, high-temperature and high-pressure steam sterilization, microwave treatment and other technologies. Common incineration methods will cause environmental pollution and the treatment of gas products, and the tail products after sterilization treatment or chemical disinfection treatment still need to be finally landfilled, which is easy to cause secondary pollution to the soil. The more environmentally friendly treatment method is high-temperature pyrolysis treatment, but there are problems in the treatment process that the waste is not evenly broken, resulting in more energy consumption in the pyrolysis process. At the same time, waste plastics and waste rubber products are all recyclable resources, and direct incineration causes serious waste of resources. At present, the temperatures of conventional high-temperature pyrolysis medical waste devices are relatively high, and it takes a long time and a lot of energy to raise the temperature. Summary of the Invention

[0004] The present invention overcomes the deficiencies of the prior art and provides a subcritical water treatment device for medical waste and a treatment method thereof, aiming to solve how to quickly break waste in the prior art, while reducing energy loss in the pyrolysis process and realizing the recycling of resources.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a subcritical water treatment method for medical waste, comprising the following steps:

[0006] S1. Mixing and pressurizing: Mix medical waste and crop waste and put them into a number of reaction tanks, and continuously pressurize the number of reaction tanks at the same time until the pressure is 5.46 MPa - 9.3 MPa and the temperature is greater than 200 °C;

[0007] S2. Intermittent pressure reduction: It includes the following steps: ① Instantaneously reduce the pressure of a single tank within 1 - 2 s, reduce the internal air pressure to atmospheric pressure and keep the air pressure unchanged; ② After the pressure reduction of a single tank is completed, repeat step ① for adjacent tanks, and at the same time, open the connecting plate between adjacent tanks within 1 - 3 s; ③ Repeat steps ① and ② until the pressure reduction of all tanks is completed;

[0008] S3. Preliminary pressurization: Add water to the tank obtained in S2 and adjust the water content to 15% - 35%, close all valves and send in steam to heat and pressurize it until the temperature reaches 135°C - 250°C and the pressure reaches 0.86 - 1.98 MPa;

[0009] S4. Continuous pressurization: Add organic heat carrier to the heating furnace, realize the circulation of the organic heat carrier with a temperature higher than 200°C in the heating layer, and at the same time continue to heat and pressurize so that the temperature in the reaction tank is 250°C - 350°C and the pressure is 1.98 MPa - 9.3 MPa;

[0010] S5. Product collection: After S4 is completed, discharge the remaining water vapor and heat in the tank and collect the products in the tank.

[0011] It should be noted that based on the production principle of popcorn, continuously increasing and then reducing the pressure of the reaction tank will cause the cell walls of crop waste to break and explode, tear the plant tissue and disperse it into fibers. During this process, the crop waste will form a diffusive explosion, and at the same time drive the medical waste to spread in the tank in the form of an explosion.

[0012] In a preferred embodiment of the present invention, the direction of pressure reduction of the tank in S2 is to first reduce the pressure of the central tank, and then reduce the pressure of the two side tanks in sequence. Due to the energy attenuation after a single explosion, the oscillation frequency and oscillation speed of the crop waste and medical waste in the sealed reaction tank will decrease to some extent. Reducing the pressure in the order of the central tank first and then the two side tanks in sequence can make the oscillation transfer between adjacent tanks, increase the end value of the attenuation of the previous oscillation, and thus further improve the explosion and fragmentation effect.

[0013] In a preferred embodiment of the present invention, the direction of pressure reduction of the tank in S2 is to start from one end and reduce the pressure to the other end in sequence, forming a segmented energy supply form, improving the explosion effect in the next stage. At the same time, part of the explosion oscillation energy is transferred back to the previous tank, improving the explosion and fragmentation effect of a single tank to a certain extent.

[0014] In a preferred embodiment of the present invention, the crop waste is waste with a cell wall structure, such as straw waste. Utilizing the characteristic that its cell wall will be damaged and generate explosive force when pressurized and then depressurized, the mixed waste is fragmented.

[0015] It should be noted that since the water content, air pressure, temperature, physical state, and substance content in adjacent tanks are not exactly the same, the blasting oscillation energy generated by adjacent tanks is also different, resulting in different energy oscillation attenuation and different energy replenishment.

[0016] The present invention also provides a subcritical water treatment device for medical waste, including a mixing bin and a plurality of reaction tanks connected to the mixing bin. It is characterized in that a steam generator, a water tank, and a heating furnace are further connected to the side of the reaction tank.

[0017] The mixing bin includes a waste bin and a storage bin. The mixing bin is arranged on one side of the reaction tank. A plurality of the reaction tanks are interconnected through a plurality of connecting plates, and the movement of the connecting plates in the vertical direction is controlled by an electrical component.

[0018] A pressure reducing control valve, a temperature display, and a pressure display are provided on the reaction tank. A heating layer is installed at the lower part. A drain pipe is provided on the heating layer. The heating layer is connected to the heating furnace through pipe three, and an organic heat carrier is added inside the heating furnace.

[0019] The reaction tanks are respectively connected to the steam generator, the water tank, and the heating furnace through pipe one, pipe two, and a reflux pipe.

[0020] The organic heat carrier includes diphenyls, diphenyl ethers, alkyl phenyls, alkyl naphthalenes, silicone oils, etc.

[0021] In a preferred embodiment of the present invention, the dust collector is one of a tangential dust collector and an axial dust collector, or multiple dust collectors are connected in parallel to form a multi-tube dust collector.

[0022] In a preferred embodiment of the present invention, a pressure regulating valve is provided on the connecting pipe between the reaction tank and the dust collector, and a pressure regulating valve is also provided on the connecting pipe between the reaction tank and the steam generator.

[0023] In a preferred embodiment of the present invention, the drain pipe is connected to a collection box, and the collection box is used to collect the liquid substances generated after the reaction.

[0024] It should be noted that in the part of the pressure reducing control valve inside the tank, a protective cover is provided along the periphery to reduce the damage to the pressure reducing control valve caused by the waste with explosion oscillation during blasting.

[0025] In a preferred embodiment of the present invention, the reaction tank is also connected to a boosting module, and the water temperature in the water tank is 125 - 150 °C, and the pressure is 0.195 - 1.385 MPa.

[0026] The present invention solves the defects in the background technology, and the present invention has the following beneficial effects:

[0027] (1) In the present invention, pretreatment is carried out on medical waste, namely blasting and crushing treatment. By utilizing the characteristic that an object will form a state similar to explosion after continuous pressurization and then instantaneously depressurization, the medical waste and crop waste are mixed and then pressurized and depressurized, so that the crop waste preferentially forms an explosion and drives the medical waste to oscillate back and forth in a diffusion manner in a sealed tank body, destroying the external morphological structure of the medical waste, and then causing the medical waste itself to explode, changing its internal form into a broken fibrous mixture, which is convenient for subsequent subcritical water treatment of the waste.

[0028] (2) In the present invention, a number of interconnected reaction tanks are designed. The blasting duration of substances in a single tank body and the intercommunication duration between adjacent tank bodies are respectively controlled by a pressure reducing valve and a connecting plate, forming segmented blasting so that blasting energy is interconnected between adjacent tank bodies, reducing energy attenuation and producing a superimposed effect on the explosion oscillation result, improving the blasting effect to a certain extent; at the same time, since the water content, air pressure, temperature, substance form and substance content in the tank body are not completely the same, the blasting oscillation energy generated by adjacent tank bodies is also different, resulting in different energy oscillation attenuation and different energy replenishment.

[0029] (3) In the present invention, different blasting sequences are also provided to produce different effects, including: ① The sequence of first depressurizing the central tank body and then the two side tank bodies in turn. Due to energy attenuation after a single blasting, the oscillation frequency and oscillation speed of the crop waste and medical waste in the sealed reaction tank will decrease to some extent. This sequence can enable the oscillation to be transmitted between adjacent tank bodies, increasing the final value of the previous oscillation attenuation, thereby further improving the blasting and crushing effect; ② The sequence of starting from one end and depressurizing to the other end in turn, forming a segmented energy supply form, improving the blasting effect of the next stage. At the same time, part of the blasting oscillation energy is transmitted back to the previous tank body, improving the blasting and crushing effect of a single tank body to a certain extent.

[0030] (4) In the present invention, through high temperature and high pressure, various bacteria, viruses, fungi and other sources of infection can be completely destroyed. At the same time, by adopting the method of segmented pressurization and heating, different substances are treated and extracted, reducing the probability of the existence of incompletely treated substances and improving the efficiency of waste treatment; in addition, this device does not produce substances such as dioxin and carbon dioxide, is pollution-free to the environment, and the tail products of the treatment can be used as fuel coal for industrial incinerators and hospital boilers, which is environmentally friendly and harmless. Description of the Drawings

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings;

[0032] Figure 1 is a schematic flow chart of a preferred embodiment of the present invention;

[0033] Figure 2 is a schematic structural diagram of a preferred embodiment of the present invention;

[0034] In the figure: 1, reaction tank; 2, heating furnace; 3, dust collector; 4, deodorizer; 5, heating layer; 6, water outlet; 7, mixing bin; 8, steam generator; 9, water tank; 10, pressure regulating valve; 11, pressure reducing control valve. Detailed implementation manners

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0036] Many specific details are set forth in the following description in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0037] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as limiting the protection scope of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Therefore, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0038] In the description of this application, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "linkage" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood through specific circumstances.

[0039] As Figure 1 shown, a schematic flow diagram of a subcritical water treatment method for medical waste includes the following steps:

[0040] S1. Mixing and pressurizing: Mix medical waste and crop waste with cell wall structures and put them into several reaction vessels, and simultaneously continuously pressurize the several reaction vessels until the pressure reaches 5.46 MPa - 9.3 MPa and the temperature is greater than 200 °C;

[0041] S2. Intermittent depressurization: It includes the following steps: ① Instantaneously depressurize a single tank within 1 - 3 s, reduce the internal air pressure to atmospheric pressure and keep the air pressure unchanged; ② After the depressurization of a single tank is completed, repeat step ① for the adjacent tank, and at the same time open the connecting plate between the adjacent tanks within 1 - 2 s; ③ Repeat steps ① and ② until the depressurization of all tanks is completed;

[0042] S3. Preliminary pressurization: Add water to the tank obtained in S2 and adjust the water content to 15% - 35%, close all valves and send in steam to heat and pressurize it until the temperature reaches 135 °C - 250 °C and the pressure reaches 0.86 - 1.98 MPa;

[0043] S4. Continuous pressurization: Add an organic heat carrier to the heating furnace to achieve the circulation of the organic heat carrier with a temperature greater than 200 °C in the heating layer, and at the same time continue to heat and pressurize so that the temperature in the reaction vessel is 250 °C - 350 °C and the pressure is 1.98 MPa - 9.3 MPa;

[0044] S5. Product collection: After S4 is completed, discharge the remaining water vapor and heat in the tank and collect the products in the tank.

[0045] Among them, in S2, the direction of depressurizing the tank is to first depressurize the central tank, and then depressurize the two side tanks in sequence.

[0046] Among them, in S2, the direction of depressurizing the tank is to start from one end and depressurize to the other end in sequence.

[0047] As Figure 2As shown in the figure, a schematic structural diagram of a subcritical water device for medical waste, including: a mixing bin 7, a number of reaction tanks 1, a steam generator 8, a heating furnace 2, a dust collector 3, and a deodorizer 4; the mixing bin 7 is arranged on one side of the number of reaction tanks 1, the dust collector 3 is connected to the outlet at the bottom of the reaction tank 1 and the deodorizer 4 through pipeline four, the reaction tank 1 is provided with a pressure reducing control valve 11, a temperature display, and a pressure display, and a heating layer 5 is installed at the lower part, a drain pipe 6 is provided on the heating layer 5, the heating layer 5 is connected to the heating furnace 2 through pipeline three, and an organic heat carrier is added inside the heating furnace 2.

[0048] The reaction tanks 1 are respectively connected to the steam generator 8, the water tank 9, and the heating furnace 2 through pipeline one, pipeline two, and a reflux pipeline, and pressure regulating valves 10 are provided on both pipeline 1 and pipeline four.

[0049] An organic heat carrier is added inside the heating furnace 2, including diphenyls, diphenyl ethers, alkylphenyls, alkylnaphthalenes, silicone oils, etc.

[0050] The dust collector 3 is one of a tangential dust collector and an axial dust collector, or multiple dust collectors are connected in parallel to form a multi-tube dust collector.

[0051] The number of reaction tanks 1 is also connected to a pressurization module and the water tank 9, and the water temperature in the water tank 9 is 125 - 150 °C and the pressure is 0.195 - 1.385 MPa.

[0052] The present invention pre-treats medical waste, that is, blasting and crushing treatment. Utilizing the characteristic that an object will form a state similar to an explosion after continuous pressurization and then instantaneously depressurization, the medical waste and crop waste are mixed and then pressurized and depressurized, so that the crop waste forms an explosion first and drives the medical waste to oscillate back and forth in a diffusion manner in a sealed tank body, destroying the external morphological structure of the medical waste, and then causing the medical waste itself to explode, changing its internal form into a broken fibrous mixture, so as to facilitate the subsequent subcritical water treatment of the waste.

[0053] To improve the effect of blasting and crushing, a number of interconnected reaction tanks are designed. By controlling the blasting duration of the substances in a single tank body and the intercommunication duration between adjacent tank bodies, segmented blasting is formed to make the blasting energy communicate between adjacent tank bodies, reduce the attenuation of energy and produce a superimposed effect on the explosion oscillation result, and to a certain extent improve the blasting effect; at the same time, since the water content, air pressure, temperature, substance form, and substance content in the tank body are not completely the same, the blasting oscillation energy generated by adjacent tank bodies is also different, thus resulting in different energy oscillation attenuation and different energy replenishment.

[0054] In the present invention, different blasting sequences are also provided to produce different effects, including: ① First, the central tank body, and then the pressure of the two side tank bodies is reduced in sequence. Due to the energy attenuation after a single blasting, the oscillation frequency and oscillation speed of crop waste and medical waste in the sealed reaction tank will decrease to some extent. This sequence can enable the oscillation to be transmitted between adjacent tank bodies, increase the final value of the attenuation of the previous oscillation, and thus further improve the blasting and crushing effect; ② Starting from one end, the pressure is reduced in sequence to the other end, forming a segmented energy supply form, improving the blasting effect of the next stage. At the same time, part of the blasting oscillation energy is transmitted back to the previous tank body, improving the blasting and crushing effect of a single tank body to a certain extent.

[0055] In the present invention, through high temperature and high pressure, various bacteria, viruses, fungi, and other sources of infection can be completely destroyed. At the same time, by adopting the method of segmented pressure increase and temperature increase, different substances are processed and extracted, reducing the probability of the existence of incompletely processed substances and improving the efficiency of waste treatment; in addition, this device does not produce substances such as dioxin and carbon dioxide, is pollution-free to the environment, and the tail products of treatment can be used for other purposes, which is environmentally friendly and harmless. Specific Embodiment 1

[0057] A subcritical water treatment method for medical waste includes the following steps:

[0058] S1. Mixing and pressurizing: Mix medical waste and crop waste with cell wall structure and put them into several reaction tanks, and continuously pressurize several reaction tanks at the same time until the pressure is 6.8 MPa and the temperature is 223 °C;

[0059] S2. Intermittent pressure reduction: includes the following steps: ① Instantaneously reduce the pressure of the first tank on the left within 1 s, reduce the internal air pressure to atmospheric pressure and keep the air pressure unchanged; ② After the pressure reduction of the first tank is completed, repeat step ① for its adjacent tank, and at the same time open the connecting plate between adjacent tanks within 2 s; ③ Starting from the first tank on the left, reduce the pressure to the right tank until the pressure reduction of all tanks is completed;

[0060] S3. Preliminary pressurizing: Add water to the tank body obtained in S2 and adjust the water content to 19%, close all valves and send in steam to raise the temperature and pressure to 147 °C and 1.06 MPa;

[0061] S4. Continuous pressurizing: Add organic heat carrier to the heating furnace, and at the same time continue to heat and pressurize so that the temperature in the reaction tank is 276 °C and the pressure is 3.68 MPa;

[0062] S5. Product collection: After S4 is completed, discharge the remaining water vapor and heat in the tank body and collect the products in the tank body. Specific Embodiment 2

[0064] A subcritical water treatment method for medical waste, comprising the following steps:

[0065] S1. Mixing and pressurizing: Mix medical waste and crop waste with cell wall structures and put them into several reaction tanks, and continuously pressurize the several reaction tanks simultaneously until the pressure reaches 5.98 MPa and the temperature reaches 216 °C;

[0066] S2. Intermittent depressurization: including the following steps: ① Instantaneously depressurize the middle tank within 2 s, reduce the internal air pressure to atmospheric pressure and keep the air pressure unchanged; ② After the depressurization of the middle tank is completed, repeat step ① for the tanks on its left and right sides, and at the same time open the connecting plates between the left tanks within 2 s and open the connecting plates between the right tanks within 1 s; ③ Starting from the middle tank, depressurize the tanks on both sides in the order of left first and then right until the depressurization of all tanks is completed;

[0067] S3. Preliminary pressurization: Add water to the tanks obtained in S2 and adjust the water content to 21%, close all valves and send in steam to heat and pressurize it to a temperature of 140 °C and a pressure of 1.22 MPa;

[0068] S4. Continuous pressurization: Add organic heat carrier to the heating furnace, and at the same time continue to heat and pressurize so that the temperature in the reaction tank is 300 °C and the pressure is 4.03 MPa;

[0069] S5. Product collection: After S4 is completed, discharge the remaining water vapor and heat in the tank and collect the products in the tank.

[0070] Comparative example

[0071] A process schematic diagram of a subcritical water treatment method for medical waste, comprising the following steps:

[0072] S1. Material mixing: Mix medical waste and crop waste with cell wall structures after being processed by a crusher and put them into several reaction tanks;

[0073] S2. Preliminary pressurization: Add water to the tanks and adjust the water content to 19%, close all valves and send in steam to heat and pressurize it to a temperature of 148 °C and a pressure of 1.06 MPa;

[0074] S3. Continuous pressurization: Add organic heat carrier to the heating furnace, and at the same time continue to heat and pressurize so that the temperature in the reaction tank is 283 °C and the pressure is 3.77 MPa;

[0075] S4. Product collection: After S3 is completed, discharge the remaining water vapor and heat in the tank and collect the products in the tank.

[0076] The experimental results show that the water contents in the products of Example 1, Example 2 and the comparative example are 9.56%, 9.09% and 10.56% respectively, and the gross calorific value on dry basis Qgr.d are 26.95 MJ / kg, 28.6 MJ / kg and 24.09 MJ / kg respectively. It can be seen therefrom that the waste treated by explosion fragmentation in the present invention has lower impurity content after subcritical water treatment, and the calorific value of the product is higher, having better thermal energy recovery and utilization value, and can further be used as fuel coal for industrial incinerators and hospital boilers.

[0077] Meanwhile, the proportion of solid matter in the waste before subcritical water treatment was measured. The contents of large solid blocks (with volume greater than 1 cm 3 , and the length of the thickest part greater than 0.5 cm) in Example 1, Example 2 and the comparative example are 12.65%, 9.6% and 16.52% respectively. It can be seen therefrom that the waste treated by explosion fragmentation has smaller volume and higher degree of fibrosis, which is more conducive to subcritical water reaction.

[0078] Based on the ideal embodiments of the present invention as the inspiration, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A subcritical water treatment device for medical waste, comprising a mixing bin and a plurality of reaction tanks connected to the mixing bin, characterized in that, A steam generator, a water tank and a heating furnace are also connected to the side of the reaction tank. The mixing bin includes a waste bin and a storage bin. The mixing bin is arranged on one side of the reaction tank. A number of the reaction tanks are interconnected by a number of connecting plates, and the movement of the connecting plates in the vertical direction is controlled by electrical components. The reaction tank is provided with a pressure reducing control valve, a temperature display and a pressure display. A heating layer is installed at the lower part. A drain pipe is provided on the heating layer. The heating layer is connected to the heating furnace through Pipeline 3, and an organic heat carrier is added inside the heating furnace. Among them, the connecting plate and the pressure reducing control valve are used to control the blasting duration of the substances in a single tank body and the intercommunication duration between adjacent tank bodies, so as to form segmented blasting and make the blasting energy intercommunicate between adjacent tank bodies. By performing intermittent pressure reduction on a number of reaction tanks, specifically: ① Instantaneously reduce the pressure of a single tank body within 1-3 s, reduce the internal air pressure to atmospheric pressure and keep the air pressure unchanged; ② After the pressure reduction of a single tank body is completed, repeat Step ① for adjacent tank bodies, and at the same time open the connecting plates between adjacent tank bodies within 1-2 s; ③ Repeat Steps ① and ② until the pressure reduction of all tank bodies is completed. The reaction tanks are respectively connected to the steam generator, the water tank and the heating furnace through Pipeline 1, Pipeline 2 and a reflux pipeline.

2. The subcritical water treatment device for medical waste according to claim 1, wherein: The reaction tank is connected to a dust collector and a deodorizer through Pipeline 4.

3. A subcritical water treatment device for medical waste according to claim 2, characterized in that: A pressure regulating valve is provided on Pipeline 1, and a pressure regulating valve is also provided on Pipeline 4.

4. The medical waste subcritical water treatment device according to claim 2, characterized in that: The dust collector is one of a tangential dust collector or an axial dust collector, or multiple dust collectors are connected in parallel to form a multi-tube dust collector.

5. A subcritical water treatment device for medical waste according to claim 1, characterized in that: The drain pipe is connected to a collection box.

6. The subcritical water treatment device for medical waste according to claim 1, wherein: The reaction tank is also connected to a boosting module. The temperature of the water in the water tank is 125-150 °C, and the pressure is 0.195-1.385 MPa.

7. A subcritical water treatment method for medical waste, based on the subcritical water treatment device for medical waste according to any one of claims 1-6, characterized in that, It includes the following steps: S1. Mixing and pressurizing: Mix medical waste and crop waste and put them into a number of reaction tanks, and simultaneously perform continuous heating and pressurizing on a number of reaction tanks. S2. Intermittent pressure reduction: Reduce the pressure of the tank bodies in the pressure reduction direction. First, instantaneously reduce the pressure of a single tank body, and then instantaneously reduce the pressure of adjacent tank bodies until the pressure reduction of all tank bodies is completed. S3. Preliminary pressurizing: Add water to the tank bodies obtained in S2 and adjust the water content, close all valves and send in steam to heat and pressurize them. S4. Continuous pressurizing: Add an organic heat carrier to the heating furnace, realize the circulation of the organic heat carrier in the heating layer, and at the same time continue to heat and pressurize so that the temperature and pressure in the reaction tank are both higher than those in S3. S5. Product collection: After S4 is completed, discharge the remaining water vapor and heat in the tank body and collect the products in the tank body.

8. A method for subcritical water treatment of medical waste according to claim 7, characterized in that: In S2, the pressure reduction direction of the tank bodies is to first reduce the pressure of the central tank body, and then sequentially reduce the pressure of the tank bodies on both sides.

9. A method for subcritical water treatment of medical waste according to claim 7, characterized in that, In S2, the pressure reduction direction of the tank bodies is to start from one end and sequentially reduce the pressure to the other end.

10. A method for subcritical water treatment of medical waste according to claim 7, characterized in that: The crop waste is waste with a cell wall structure.

Images