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Petroleum processing, production of industrial solvents, chemical products, as well as organic materials storage and transportation process will produce volatile organic compounds of VOCs. VOCs (?) In the class range of the most toxic, harm to human health; involved in the formation of photochemical smog and aerosol pollution of the environment; halogenated organics can damage the ozone layer. The VOCs pollution problems has caused the world attaches great importance to the United States, Japan, the European Union many years ago that the implementation of a strict VOCs emissions standards. Approach (condensation, absorption, adsorption, and incineration) for organic waste gas processing low concentration, flow on the technical and economic limitations. Researching new ways to recycle or decompose the organic waste gas is one of the important content of China's environmental protection work. With the development of low-temperature plasma technology, low temperature plasma oxidation method is considered to be an effective way to deal with volatile organic compounds (VOCs) exhaust has the advantages of high efficiency, low energy consumption, simple structure, no secondary pollution. Basically deal with such a low temperature plasma oxidation of the exhaust pulse corona discharge, dielectric barrier-discharge method, high-frequency capacitively coupled discharge method, and for the study of high-frequency inductively coupled discharge method than previous scientific studies, less. This paper is based on the issue, the use of high-frequency inductively coupled discharge plasma technology experimental study of formaldehyde gas processing. Summarizes the latest research progress of harmful gas discharge plasma technology processing, based on a large number of relevant literature, the basic principles and trends. According to the research objectives of this thesis and the experimental conditions, the design of the high-frequency inductively coupled discharge plasma formaldehyde gas processing experimental apparatus and experimental program carried out high-frequency inductively coupled the formaldehyde gas discharge plasma processing experimental study, a series of experimental data, from experimental The data derived from the influencing factors and the influence of formaldehyde. Experimental results show that the high-frequency inductively coupled discharge low concentrations of formaldehyde gas plasma treatment allows the formaldehyde removal rate of 99.3%; formaldehyde removal rate increases with the discharge treatment time and increase in the input power; formaldehyde removal rate with the system pressure , flow, and the initial concentration of formaldehyde increases. The experiments also showed that the temperature is always maintained at room temperature during the whole experiment, the reactor system. The mechanism based on the experimental results, that: the discharge in the high-frequency inductively coupled plasma processing formaldehyde gas, since the active species generated in the role of formaldehyde molecules will form the excited state of formaldehyde molecules; formaldehyde molecules of the CH bond than C = O bond is easily broken, thereby forming · CHO radical, and a series of reactions. The excited states of oxygen atoms of oxygen in the gas in the discharge process can be formed, and · CHO radical or other atoms, molecules collide generate various oxygen free radicals, these radicals react further. Finally, the formation of CO2, H2O, CO, research results show that the high-frequency inductively coupled discharge plasma treatment formaldehyde can effectively remove indoor formaldehyde gas can get the effective removal of formaldehyde.
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