Device and process for disinfection and sterilization of medical waste based on friction heat

Abstract

The present invention discloses a device and process for disinfecting and sterilizing medical waste based on friction heat, the device comprises a chamber, the chamber is provided with a closed sterilization chamber, a temperature sensor, a drive device, an exhaust pipe, a water supply pipe and a drainage pipe, a filter, a pipe fan, a control system, an ultraviolet lamp and a fan; the closed sterilization chamber is built with a rotor with a blade for grinding or crushing waste, and at the same time, the blade and the waste generate heat through friction to disinfect and sterilize. The device of the present invention can treat medical waste on site.

Description

Technical Field

[0001] The present invention relates to the technical field of medical waste disinfection and treatment, and in particular to a device and process for disinfecting and sterilizing medical waste based on friction heat. Background Art

[0002] Medical waste refers to infectious, toxic and other dangerous wastes generated by medical institutions in medical, preventive and health-care related activities. It carries a huge number of pathogens and a wide variety of species. It spreads in the form of spatial transmission, acute transmission, cross transmission and latent transmission. It is highly infectious, biologically toxic and corrosive. According to the National List of Hazardous Wastes, medical waste is hazardous waste and must be collected, transported, stored and disposed of in accordance with the national hazardous waste treatment requirements. It cannot be mixed with domestic garbage at will, nor can it be directly landfilled on site to avoid virus transfer and spread and secondary environmental pollution.

[0003] At present, the main methods for the treatment and disposal of medical waste in my country are high-temperature steam and high-temperature incineration, but both have disadvantages such as limited treatment types, high investment costs, and large secondary pollution. In addition, both high-temperature steam and high-temperature incineration achieve the treatment of medical waste by collecting it first and then disposing it in a centralized manner, which increases the transportation cost and environmental risks during the transportation process. At present, there is no mature batch-type, on-site medical waste treatment and disposal technology in China. Therefore, it is necessary to seek a new technical solution to solve the above problems.

[0004] A Chinese patent document with application number CN201920328221.X discloses a disinfection and crushing device for a medical waste treatment system. By designing the first rolling bearing in the housing, the crushing speed of medical waste can be effectively improved, and the crushing is thorough and uniform in particle size. At the same time, the crushed particles can also be directly and evenly disinfected.

[0005] A Chinese patent document with application number CN201810290725.7 discloses an infectious medical waste treatment system, which includes a disinfection tank, a crushing tower, a combustion chamber and an exhaust gas purification chamber connected in sequence. It can sterilize, dry, physically crush and burn the infectious medical waste in sequence under high temperature and high pressure, and purify the exhaust gas after combustion before discharging it into the atmosphere. The whole process does not produce toxic pollutants.

[0006] A Chinese patent document with application number CN201920140515.X discloses a waste gas treatment device for high-temperature sterilization of medical waste, which is equipped with an ultraviolet sterilization device, a disinfection device and an alarm device. It can disinfect and sterilize medical waste to make the sterilization more thorough and improve the sterilization effect. It can perform the first disinfection treatment on medical waste to prevent fungi on the medical waste from contaminating the surrounding environment. It can detect the gas to check whether it meets the emission standards.

[0007] The above-mentioned thermal sterilization or disinfection usually involves blowing in saturated steam through an autoclave system, or blowing in superheated steam at a temperature of about 180°C through a dry system, or utilizing wall heating to achieve heat transfer to the waste pile. However, due to the problem of too low a transfer coefficient, the heating cycle for the treated material is very long. Although microwave heating can utilize microwave radiation to penetrate heat into the interior of the waste, this method is difficult to achieve the temperature required for sterilization. In addition, the above-mentioned methods all achieve the treatment of medical waste by first collecting and then disposing of it in a centralized manner, which increases transportation costs and environmental risks during the transportation process. At present, there is no mature batch-based, on-site medical waste treatment and disposal technology in China. Summary of the invention

[0008] The present invention provides a device for disinfecting and sterilizing medical waste based on friction heat, which fully grinds and crushes solid medical waste and uniformly heats the solid medical waste with the friction heat generated, thereby ensuring that the internal solid medical waste is completely sterilized.

[0009] The specific technical solutions are as follows:

[0010] A device for disinfecting and sterilizing medical waste based on friction heat, comprising a chamber, wherein the chamber is provided with:

[0011] The sealed sterilization chamber has a feed port, a discharge port, a water supply port, a drain port, an air supply port, and an exhaust port. A rotor with a blade is built in, which is used to grind or crush the waste. At the same time, the friction between the blade and the waste generates heat for disinfection and sterilization. The water supply port is connected to a water spray system that sprays water into the sterilization chamber.

[0012] Temperature sensor, used to detect the temperature in the sterilization chamber and transmit it to the control system;

[0013] A driving device drives the rotor to rotate, and a frequency converter is used to control the rotor speed to be 300-2800 rpm;

[0014] an exhaust pipeline, connected to the exhaust port;

[0015] The water supply pipeline and the drainage pipeline are connected to the water supply port and the drainage port respectively;

[0016] The filter is arranged between the exhaust port and the exhaust pipe to purify particulate matter, microorganisms and steam in the exhaust gas;

[0017] The pipeline fan is arranged on the exhaust pipeline and is used to make the sterilization chamber and the exhaust pipeline in a negative pressure state;

[0018] The control system controls the rotation of the rotor and the water spray system according to the temperature in the sterilization chamber, and also controls the feeding and unloading process;

[0019] Ultraviolet lamp, used for room disinfection;

[0020] The fan is used to maintain negative pressure in the chamber.

[0021] The device for disinfecting and sterilizing medical waste based on frictional heat of the present invention adopts the "frictional heat treatment" technology, and controls the blades on the rotor through the frequency converter in the sterilization chamber, and fully grinds and crushes the solid medical waste. At the same time, the friction heat generated evenly heats the solid medical waste, ensuring that the solid medical waste inside the sterilization chamber is completely sterilized. The device for disinfecting and sterilizing medical waste based on frictional heat of the present invention can be used to dispose of medical waste on-site, which can save the storage and transportation of solid medical waste and effectively reduce the environmental pollution caused by vehicle emissions and waste disposal during transportation. In particular, for remote areas that are not covered by the current solid medical waste disposal system, the device for disinfecting and sterilizing medical waste based on frictional heat of the present invention can also be used to treat medical waste on-site.

[0022] Preferably, a plurality of fixed impact plates are provided on the inner wall of the sterilization chamber; further preferably, blades are installed on the fixed impact plates.

[0023] The rotation of the rotor in the sterilization chamber drives the blade, causing the medical waste in the sterilization chamber to rotate in the sterilization chamber and collide and rub against the fixed impact plate on the inner wall of the sterilization chamber. The medical waste is crushed and generates heat under the interaction between the fixed impact plate and the blade on the rotor, and the temperature in the sterilization chamber rises, achieving the effect of disinfection and sterilization.

[0024] Preferably, the blades on the rotor and the blades on the fixed impact plate are made of stainless steel alloy.

[0025] The filter comprises a primary filter, a secondary filter and a high efficiency air filter; the waste gas in the sterilization chamber passes through the primary filter, the secondary filter and the high efficiency air filter in sequence.

[0026] The fillers in the primary filter and the secondary filter are Raschig rings or Pall rings; the primary filter and the secondary filter are provided with spray heads, and the flow direction of the spray water is opposite to that of the exhaust gas.

[0027] The primary filter and the secondary filter filter out particulate matter and steam in the exhaust gas. The primary filter and the secondary filter are provided with wastewater discharge ports, and the wastewater discharge ports of the primary filter and the secondary filter merge with the drain port of the sterilization chamber.

[0028] The high efficiency air filter is composed of a carbon filter and an absolute filter, which further removes particulate matter and microorganisms in the exhaust gas. The exhaust gas filtered by the high efficiency air filter can be directly discharged through the exhaust pipe.

[0029] The filler of the carbon filter is activated carbon; the filler of the absolute filter is glass fiber.

[0030] The pipeline fan maintains a negative pressure environment in the sterilization chamber and exhaust pipeline to prevent exhaust gas leakage. The ultraviolet lamp in the chamber disinfects the air in the chamber, and the fan maintains the entire chamber in a negative pressure state, ensuring that the chamber is in a low environmental risk state.

[0031] The present invention also provides a method for disinfecting and sterilizing medical waste using the above device, comprising the following steps:

[0032] (1) Add medical waste into a closed sterilization chamber. The rotor rotates to drive the blades to impact and rub the medical waste to grind and crush the medical waste. At the same time, heat is generated to increase the temperature in the sterilization chamber. The temperature sensor monitors the temperature in the sterilization chamber in real time.

[0033] (2) When the temperature in the sterilization chamber reaches 140-200°C, the control system controls the water spray system to spray water into the sterilization chamber to cool it down. When the temperature drops to 90-100°C, the control system opens the discharge port to discharge the material;

[0034] (3) The waste gas in the sterilization chamber enters the filter through the exhaust port for purification and is then discharged through the exhaust pipe.

[0035] Existing thermal sterilization or disinfection usually involves blowing in saturated steam at a pressure of about 0.5 Pa through an autoclave system, or blowing in hot air / superheated steam at a temperature of about 180°C through a dry system, or using wall heating to transfer heat to the waste pile. However, due to the problem of too low transfer coefficient, the heating cycle for the treated material is very long. Although microwave heating can use microwave radiation to penetrate heat into the waste, this method is difficult to reach the temperature required for sterilization. In addition, the above methods all achieve the treatment of medical waste by first collecting and then disposing of it in a centralized manner, which increases transportation costs and environmental risks during transportation.

[0036] The present invention adopts "friction heat treatment" technology. The blade is controlled by a frequency converter inside the sterilization chamber to fully grind and crush the solid medical waste. At the same time, the friction heat generated will evenly heat the medical waste. The temperature peak can reach 100-200℃, ensuring that the medical waste inside the sterilization chamber is completely sterilized. Then water is automatically sprayed into the treated waste, and it is automatically unloaded after cooling it to 90-100℃.

[0037] Preferably, in step (2), when the temperature in the sterilization chamber reaches 150° C., the control system controls the water spray system to spray water into the sterilization chamber to cool it down.

[0038] Preferably, based on the weight of the medical waste, the medical waste contains 5-20% water.

[0039] The medical waste contains a certain amount of liquid, such as discarded blood samples, human tissue fluid, etc. If the medical waste itself does not contain components that can provide humidity, it is necessary to add about 5-20% of tap water or other components that provide humidity to the medical waste.

[0040] The treatment process of the present invention has a good disinfection and sterilization effect on medical waste. It uses prescribed biological indicators for detection and meets the requirements of relevant standards of the National Health Commission and the Ministry of Ecology and Environment. The discharged waste gas and wastewater meet the requirements of relevant standards of the Ministry of Ecology and Environment.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) The present invention fully grinds and crushes the solid medical waste, and at the same time, the friction heat generated evenly heats the solid medical waste, which has high heating efficiency and can ensure that the internal solid medical waste is completely sterilized;

[0043] (2) Using the device for disinfecting and sterilizing medical waste based on friction heat of the present invention to dispose of medical waste on site can save the storage and transportation of solid medical waste and effectively reduce the environmental pollution caused by vehicle emissions and waste disposal during transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the structure of a device for disinfecting and sterilizing medical waste based on friction heat;

[0045] Figure 2 This is a schematic diagram of the process of the device for disinfecting and sterilizing medical waste based on friction heat. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0047] In the description of the present invention, it should be pointed out that the terms "upper", "lower", "front", "back", "top", "bottom", "inside" and "outside" etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0048] An embodiment of a device for disinfecting and sterilizing medical waste based on friction heat is as follows Figure 1 and Figure 2 As shown in the figure, it includes a sterilization chamber 1 suitable for containing waste, a rotor 1-2 with a wheel blade or blade 1-1 is installed in the sterilization chamber 1, which can be used to grind or crush the waste, and a water spray system 1-3 is also arranged above the sterilization chamber 1 to spray water to cool the sterilized residue; a temperature sensor 1-4 is arranged in the sterilization chamber 1 to accurately measure the material temperature in the sterilization chamber 1 in real time; a driving device (not shown in the figure), which can drive the rotor to a certain speed so that the temperature generated by friction is sufficient to sterilize or disinfect the waste and maintain this temperature in the chamber; a control system (not shown in the figure), which can control the entire process and can control the rotation of the rotor in the sterilization chamber, the water supply pipeline and the feeding and unloading stages according to the actual temperature; a two-stage filter to purify particulate matter in the exhaust gas and remove steam in the air flow, including a first-stage filter 2-1 and a second-stage filter 2-2; wherein the first-stage filter 2-1 is provided with a Raschig ring filler 2-12 , a water spray system 2-11 is arranged from top to bottom above the filler; a ball ring filler 2-21 is arranged in the second-stage filter 2-2; a high-efficiency air filter 3 is used to further purify particulate matter and microorganisms in the exhaust gas. A carbon filter layer 3-1 and an absolute filter layer 3-2 are arranged in sequence from bottom to top in the high-efficiency air filter 3. The main components of the carbon filter layer 3-1 and the absolute filter layer 3-2 are activated carbon and glass fiber, respectively; a pipeline fan 4 is arranged above the high-efficiency air filter 3, which can continuously pump out the gas in the container and the pipeline, so that the container is always in a negative pressure state; an exhaust pipeline 5 discharges the exhaust gas and wastewater generated by the operation; a water supply and drainage pipeline provides the water source required for the operation; other auxiliary facilities, an ultraviolet lamp (not shown in the figure) is installed in the warehouse 6 where the device is placed for disinfection, and a fan 7 is installed in the warehouse 6 where the device is placed to maintain the negative pressure state in the entire warehouse 6, ensuring that the warehouse 6 is always in a low environmental risk state.

[0049] An exhaust port is provided above the sterilization chamber 1, and the exhaust port is connected to the air inlet below the first-stage filter 2-1, the exhaust port above the first-stage filter 2-1 is connected to the air inlet below the second-stage filter 2-2, the exhaust port above the second-stage filter 2-2 is connected to the exhaust port above the high-efficiency air filter 3, and the pipeline fan 4 is installed between the exhaust port above the high-efficiency air filter 3 and the exhaust pipeline 5.

[0050] The waste gas generated in the sterilization chamber 1 passes through the first-stage filter 2 - 1 , the second-stage filter 2 - 2 and the high-efficiency air filter 3 in sequence, and is discharged through the exhaust pipe 5 .

[0051] Before sterilization, turn on the UV lamp and operate the fan 7 in the warehouse to maintain a slight negative pressure in the warehouse.

[0052] Weigh a certain load of medical waste and add it into the sterilization chamber 1. If the medical waste itself does not contain components that can provide humidity, it is necessary to add about 5-20% of tap water or other components that provide humidity to the medical waste, and close the chamber door.

[0053] Press the control switch and the process will run automatically. After about 20-50 minutes, when the temperature sensor 1-4 detects that the material temperature has risen to 150°C, the cooling water in the sterilization chamber 1 will be turned on immediately to cool the material to 95°C. The process is then ended and the material is automatically unloaded. When the prompt sound sounds, the residue can be removed and sterilization is completed.

[0054] Due to the presence of the pipeline fan 4, the waste gas in the sterilization chamber 1 is continuously pumped out and discharged after passing through the two-stage filter and the high-efficiency air filter 3. The sewage generated during the sterilization process is discharged from the sewage pipe.

[0055] After the medical waste is disinfected and sterilized as described above, the sterilization residue, waste gas and wastewater are tested. The test results are shown in Table 1-4.

[0056] Table 1 Sterilization effect test results

[0057]

[0058] Note: ND stands for Not Detected

[0059] Table 2 Exhaust gas test results

[0060]

[0061] Table 3 Detection results of odorous substances in exhaust gas

[0062]

[0063] Note: ND stands for Not Detected

[0064] Table 4 Wastewater test results

[0065]

[0066] Note: ND stands for Not Detected

[0067] The above results show that medical waste is sterilized successfully, the emission volume or emission concentration of waste gas and wastewater is low, and the environmental risks are controllable.

[0068] The embodiments described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for disinfecting and sterilizing a device for disinfecting and sterilizing medical waste based on friction heat, characterized in that: The device comprises a chamber, wherein the chamber is provided with: The sealed sterilization chamber has a feed port, a discharge port, a water supply port, a drain port, an air supply port, and an exhaust port. A rotor with a blade is built in, which is used to grind or crush the waste. At the same time, the friction between the blade and the waste generates heat for disinfection and sterilization. The water supply port is connected to a water spray system that sprays water into the sterilization chamber. Temperature sensor, used to detect the temperature in the sterilization chamber and transmit it to the control system; A driving device drives the rotor to rotate, and a frequency converter is used to control the speed of the rotor; an exhaust pipeline, connected to the exhaust port; The water supply pipeline and the drainage pipeline are connected to the water supply port and the drainage port respectively; The filter is arranged between the exhaust port and the exhaust pipe to purify particulate matter, microorganisms and steam in the exhaust gas; The pipeline fan is installed on the exhaust pipeline to continuously pump the gas in the sterilization chamber and the exhaust pipeline out, so that the sterilization chamber and the exhaust pipeline are always in a negative pressure state; The control system controls the rotation of the rotor and the water spray system according to the temperature in the sterilization chamber, and also controls the feeding and unloading process; Ultraviolet lamp, used for room disinfection; The fan is used to maintain the negative pressure in the chamber; The method comprises: (1) Adding medical waste into a sealed sterilization chamber, the rotor rotates to drive the blade to impact and rub the medical waste to grind and crush the medical waste, and at the same time generate heat to increase the temperature in the sterilization chamber; the temperature sensor monitors the temperature in the sterilization chamber in real time; the rotor rotates at a speed of 300-2800 rpm; based on the weight of the medical waste, the medical waste contains 5-20% water; (2) When the temperature in the sterilization chamber reaches 100-200°C, the control system controls the water spray system to spray water into the sterilization chamber to cool it down. When the temperature drops to 90-95°C, the control system opens the discharge port to discharge the material; (3) During the disinfection and sterilization process, the waste gas in the sterilization chamber enters the filter through the exhaust port for purification and is then discharged through the exhaust pipe.

2. The method according to claim 1, characterized in that A plurality of fixed impact plates are arranged on the inner wall of the sterilization chamber; blades are installed on the fixed impact plates.

3. The method according to claim 1, characterized in that The filter comprises a primary filter, a secondary filter and a high efficiency air filter; the waste gas in the sterilization chamber passes through the primary filter, the secondary filter and the high efficiency air filter in sequence.

4. The method according to claim 3, characterized in that The fillers in the primary filter and the secondary filter are Raschig rings or Pall rings; the primary filter and the secondary filter are provided with spray heads, and the flow direction of the spray water is opposite to that of the exhaust gas.

5. The method according to claim 1 or 4, characterized in that: The primary filter and the secondary filter are provided with wastewater discharge ports, and the wastewater discharge ports of the primary filter and the secondary filter are merged with the drain port of the sterilization chamber.

6. The method according to claim 3, characterized in that The high-efficiency air filter is composed of a carbon filter and an absolute filter; the filler of the carbon filter is activated carbon; and the filler of the absolute filter is glass fiber.

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