| Medical waste is considered as the No.l hazardous waste, according to the National Hazardous Wastes List. More and more medical waste are generated due to the development of modern medical science, and become a source of spreading diseases. Now scientists throughout the world are engaging in seeking effective medical waste handling methods. Although incineration can reduce the volume and weight of medical waste, and can sterilize it with high temperature, it is very easy to cause a second pollution during treatment. Pyrolysis-gasification technology not only has the advantages mentioned above but also can save energy, and much easier to control the generation of second pollution, which is regarded as an effective new treatment technology. There are a lot of technologies and equipments for medical waste treatment, but most of them come from the municipal solid waste treatment. Foundational reach on medical waste has rarely been carried out.This paper relies on National Natural Science Foundation No. 50276055 and carried out the foundational research on medical waste's pyrolysis and gasification, which can set up a foundation for further research and offer some experimental data for rotary kiln designing.Part I, firstly, according to the feature of domestic medical waste, different types of thermal treatment equipments were analyzed and compared, and found out that two-chamber rotary kiln incineration system is very suitable for medical waste treatment. Secondly, while the movement characteristics of materials in rotary kiln and its effect factor were researched, the paths and mechanisms of heat transfer in rotary kiln were analyzed.Part II, typical organic components' kinetics characteristics of pyrolysis and gasification was studied by thermo-gravimeter, and seven organic components' weight loss properties and dynamics parameters were obtained. Effect of temperature rising rate and atmosphere to each component's weight loss property was analyzed. Based on the dynamics property research results, an apparent multi-step pyrolysis-gasification reaction model was established. This paper also set up a multicomponent model based on the whole medical waste, which solved the difficulty of simulating mixed wastes' pyrolysis and gasification process.Part III, pyrolysis experiments of four components of three organics (fiber, fattiness and macromolecule) were carried out on an external-heating rotary kiln. Different affect factors of distributing of pyrolysis outcomes, pyrolysis process andproperty of gas producing were analyzed. The rising of final pyrolysis temperature favors the production of volatile in organics, increases pyrolysis gas production rate and decreases tar & char production rate while the rising of water content will affect this rule. Production of hydrocarbon in pyrolysis gas increases while final pyrolysis temperature rises.Part IV, gasification experiments of four components in rotary kiln were studied. It came out that pyrolysis properties of each component were different while gasification temperature rises. Coefficients of these changes were analyzed. In addition, reaction type of pyrolysis and gasification was compared in this paper and found out that using which reaction type had little affection on the pyrolysis process in rotary kiln.
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