Medical waste is solid or liquid waste generated in the course of medical activities such as diagnosis, laboratory tests, disposal, application and disease prevention for both humans and animals. The scope of hospital waste is very wide, such as all kinds of needles, syringes, gauze, plaster, various specimens discarded in the laboratory and pathology room, blood samples, all kinds of plastic or glass containers, infusion sets, infusion tubes, blades and a large number of wastes after the operation, a large number of disposable hospital instruments, ward-contaminated clothing and bedding and all kinds of discarded medicines and plastics, and so on. The germs contained in medical waste are dozens or even hundreds of times more than those contained in ordinary household waste, and it is a source of infection for various diseases. In the National Hazardous Waste List compiled by the State Environmental Protection Administration (SEPA), it is classified as the number one hazardous waste. In the international arena, medical waste is known as the "super killer" of human beings. Because medical waste itself with germs and viruses, medical waste collection, transportation, storage, disposal process, if any negligence, may lead to disease transmission and environmental pollution, will have a huge harm to the environment and society.
With the widespread use of disposable medical devices in China, the production of medical waste is increasing at a rate of 3% to 6% per year. 2000, there were 324,771 medical and health care institutions nationwide, with 3,177,000 hospital beds, and 2,123,000,000 consultations annually, generating about 1 million tons of medical waste. 2003 saw the ravages of SARS, and 2005 saw the outbreak of avian flu, making us more and more concerned about the spread of disease and environmental pollution. The outbreak of avian influenza in 2003, let us see more and more clearly to speed up the construction of medical waste and waste facilities, improve the harmless treatment of medical waste, sanitary landfill, incineration technology and resource comprehensive utilization of the management level, so that more white pollution into organic materials, to prevent hospitals from cross-infections, to create a safe and hygienic environment and so on the importance of the issue.
With the improvement of people's living standards, environmental awareness has gradually increased, the implementation of harmless treatment of medical waste requirements are becoming more and more stringent. Developed countries generally use a unified collection, centralized incineration of medical waste collection and treatment, medical waste collection and treatment system by the fully enclosed collection, storage, transportation and incineration facilities, to ensure that the collection and transportation of medical waste in the process of not leaking and effectively prevent the spread of pathogens.
Future medical waste treatment technology, will use pyrolysis treatment process, rather than incineration, pyrolysis treatment process will be completed in three stages:
(1) solid waste pyrolysis stage: medical waste in the high temperature, lack of oxygen, pressure, etc., the molecular chain of the organic matter began to break, resulting in the production of gas containing methane, carbon monoxide, hydrogen, tar, water vapor and so on. gas mixture. The rest is converted into residual charcoal.
(2) Mixed reaction stage: In the mixed gas reaction device, the tar, water vapor and residual charcoal in the mixed gas are converted into gas through a special process, where carbon dioxide is reduced to carbon monoxide.
(3) Combustible gas purification stage: the combustible gas produced by pyrolysis reaction tank and mixed gas reaction device, after cooling, filtering and other purification processes, i.e., new clean combustible gas is produced, which can reach the industrial gas standard and civil gas standard.
In addition, plasma technology will also be widely used in medical waste treatment. Plasma technology is the use of plasma medical waste pyrolysis furnace for waste decomposition treatment. Traditional medical waste incineration generally use the traditional gas, oil combustion method, and the use of this gas, oil combustion method of incinerator, due to the furnace temperature is not high is very easy to produce dioxin, infectious viruses can not be completely dealt with, combustion of garbage residue as a domestic waste to landfill, a long time will precipitate out of the ground, the environment caused by secondary pollution. Plasma technology provides a good way to solve such problems. Because the temperature of the reaction zone is up to 2000℃ or more, it can effectively decompose highly toxic substances that are very harmful to human beings, and is a new environmental protection technology with wide range of uses. The device can also be used for environmental protection treatment of municipal waste, medical waste, asbestos, batteries, tires, PVC and other industrial toxic and hazardous wastewater and waste gas.