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Information × Registration Number 0216U000426, 0113U001083 , R & D reports Title Development of theoretical bases and equipment for the process of fractional electromechanical welding fume catching popup.stage_title Head Vishnyakov V.I., Registration Date 04-02-2016 Organization Ohysical-Chemical Institute of the Environment and Human"s protection popup.description2 The subject of study is the particles of welding fume (WF), a multi-stage electromechanical filter (EMF) and prototype of a portable filter-ventilation unit of new generation with three-stage EMF (FVU-EMF-3). The research objective is the development of WF formation physical-mathematical model and scientific justification of fractional electromechanical WF trapping, and new generation of portable FVU for providing normalized working conditions of welders and workers of related professions creating on this basis, as well as WF recycling as a raw material for manufacture the products of industrial and domestic purpose. According to the results of the experimental studies of WF physical-chemical properties, when the shielded metal arc welding (SMAW) is applied, the factors that influence the dispersion of primary particles, WF phase composition and specific surface area were determined. World first the physical-mathematical zone model of WF formation in the ionized multicomponent vapor-gas environment with taking into account zones of thermal- and vapor photoionization, formation, charging, condensation and coalescence nuclei growth and coagulation of the primary particles, was performed. The proposed model can be used to determine the elemental composition and dispersion of primary and inhaled WF particles. The charges of the WF particles in the area of the welder breathing zone were determined. The physical-mathematical model of the WF particles interaction with welding arc ultraviolet radiation was developed. The regularities of the WF particles unipolar charging and the physical-mathematical model of WF particles charging in an electric field of corona discharge were studied. The demands to the regime of the FVU ionizer, which provides the WF particles fractionally precipitation in EMF, were determined. The possibility of a combination of WF trapping and fractionation in EMF was demonstrated for the first time. The regularities of the processes of fractional electromechanical trapping of charged WF particles flow-through perforated electrodes and the formation auto-filter layer of WF sediment on the surface of the flow-through mesh electrode in induced electric fields were determined. The possibility of controlling the process of forming the auto-filter layer of WF sediment (aerodynamic resistance) by adjusting the induced electric field intensity and polarity was shown. The physical-mathematical model of determining the efficiency of fractional WF trapping and the prototype of the three-stage EMF were developed. The design documentation for the FVU-EMF-3 was developed. The FVU-EMF-3 prototype was fabricated and tested. The WF chemisorption ability (on the example, SO2) and catalytic activity (on the example, low-temperature reaction of ozone decomposition), when SMAW with different welding materials is applied, were determined for the first time. The utilization of WF electrodes with lime type of coating, for chemisorption acid gases, and rutile, ilmenite and rutile-cellulosic covering type as low-temperature catalysts in reaction of ozone decomposition was substantiated. The prototype of sorption-filtering fibrous material, wherein the fraction (0?1?m) WF electrodes with lime type of coating was used as deposited sorbent of sulfur oxide (IV), was fabricated. The investigation results will be used: in the modeling and prediction of the biological activity of WF particles; in norming the WF threshold limit values concentrations; in sanitary-hygienic estimation of methods and welding conditions, development of new welding materials. Implementation of the results will simultaneously solve several problems: to improve the sanitary conditions in the welders working zones and the environment in the welding fabrication areas; to reduce support costs norming working conditions in manufacturing plants; to obtain significant economic and social impact through the WF fractions recycling as raw material for manufacturing of products for industrial and domestic purposes (catalysts in the reaction of ozone decomposition, sorbents acid gases, sorption-filtering materials, fillers composites and paints and others.). Product Description popup.authors Вишняков В.І. Еннан А.А. Кіро С.А. Калугін В.В. Опря М.В. Ракитська Т.Л. Семенов К.І. Тімкова К.В. Труба А.С. Фірсов А.Г. Фролов С.В. Шугарова В.В. popup.nrat_date 2020-04-02 Close