Landfill method is a common method in non incineration medical waste treatment technology. Although the landfill method is simple and low-cost, it will pollute the environment and endanger human health once it is improperly treated. In addition, three by-products (solid degradation waste, leachate, landfill gas) will also cause environmental pollution. Therefore, landfill method is not a safe method of medical waste treatment.

Chemical disinfection is the process of mixing the broken medical waste with disinfectants (peracetic acid, ozone, etc.) to kill microorganisms and decompose organic substances in the disinfection process. Disinfectants should be in full contact with medical waste to achieve better treatment effect. The degree of fragmentation of medical waste affects the penetrability of disinfectants. Chemical disinfection method has the characteristics of simple process equipment and operation, and low operation cost. However, most disinfectants are harmful to human body, and the treatment of toxic waste liquid is difficult. This method cannot be used for the treatment of radioactive waste, volatile and semi volatile waste.

Microwave treatment technology of medical waste is an alternative technology to incineration. It uses electromagnetic waves with frequencies between radio waves and infrared rays to heat the water in the waste, so as to kill bacteria and achieve the purpose of disinfection and destruction of waste. Microwave method has good sterilization and volume reduction effect, does not need disinfectant and does not produce dioxin, but the type of waste treated by microwave method is limited, and the engineering construction and operation costs are high.

High temperature and high pressure steam sterilization is a common method of medical waste treatment. Autoclave is essentially a high-temperature and high-pressure metal container, with a sealable door and a group of pipes and hatches through which steam is introduced and removed from the container. In autoclaves, this process steams the waste to destroy potential infectious effects and kill pathogens before burying the waste. Since the high-pressure sterilization method is only applicable to limited wastes and highly infectious wastes, such as microbial cultures and sharps, the combination of crushing method and high-temperature and high-pressure steam method has a better effect on the treatment of medical wastes. The treatment of medical waste by high temperature and high pressure steam method will produce toxic substances and unpleasant smell. It is necessary to strengthen the treatment of waste liquid and gas to reduce the harm to the environment.

The dry heat crushing sterilization method is to place the crushed medical waste in a sealed dry heat furnace and heat it to 100-131 ℃, using dry hot air to kill microorganisms. The dry heat crushing sterilization needs to maintain enough processing time to achieve the sterilization effect. Dry heat sterilization has the advantages of good sterilization effect, low operation cost and no need of disinfectant. However, it also has the shortcomings that medical waste must be crushed, and the dry heat treatment process will produce air pollutants and odor.

Incineration is the main method to treat medical waste all over the world. It is widely used in all kinds of medical waste, such as polyethylene plastic, paper, waste equipment, etc. Incineration is an engineering process designed to treat waste. This process decomposes the organic part of waste by thermal oxidation at a high temperature between 900-1200 ℃. Incineration treatment of medical waste can completely eliminate bacteria and decompose organic matter, and achieve volume reduction to the greatest extent. However, the flue gas produced by incineration treatment of medical waste contains smoke, acid gas, toxic organic substances (dioxins, furans, etc.) and heavy metals, so flue gas purification devices need to be equipped.

Pyrolysis treatment refers to the process of heating medical waste to 500-1000 ℃ under anoxic or anaerobic conditions. Due to the action of heat energy, the chemical bonds of thermally unstable organic substances are broken, so that macromolecules are transformed into small molecule gases, liquids and residues. The obtained pyrolysis gas can be purified and used, and can also be burned out in the secondary combustion chamber to finally obtain flue gas and ash. Pyrolysis method requires less air coefficient, less flue gas and easy treatment, and the cost is lower than that of incineration method; Acid gas environment such as anoxia and dechlorination greatly reduces the production of dioxins; There is no obvious selectivity for the treated medical waste. Its disadvantage is that the carbon in the residue is not easy to burn out.

Gasification refers to the process of converting waste into usable gas and generating energy. The gasification system includes primary chamber and secondary chamber. The cycle and temperature of the gasification system are controlled by computer and logic controller; When the temperature is 260 ℃, the volatile substances in medical waste begin to vaporize in the primary room and completely vaporize at 426 ℃; Because the primary gasification chamber is in an anoxic state, the organic matter first forms volatile organic compounds (VOC) and vaporizes, and then the volatile organic compounds are completely oxidized in the secondary chamber, thus avoiding the production of toxic by-products; The temperature of the secondary chamber is above 1000 ℃, and the high temperature ensures the killing of pathogens. This technology has the advantages of high degree of reduction, good sterilization effect, energy recovery and energy conservation. However, this technology has high cost and low cost performance, and is not applicable to radioactive waste and mercury contaminated waste.

Plasma gasification technology is a modern technology for the safe treatment of medical waste, and it is also an environmental protection technology for converting organic waste into useful products. Plasma gasification technology has high energy and can quickly decompose waste to produce small molecular intermediates. The combustible gas produced by it is completely burned in the secondary combustion chamber and finally discharged after tail gas purification. Plasma technology has the advantages of fast heat and mass transfer rate, less dioxin production, simple flue gas purification, small volume, small floor area and simple operation. It is widely used in European and American countries.