The utility model provides a be applied to the the wet dedusting device among the coal gasification technical field, include bleed pipe, hand wheel, sealing member, heavily stone roller, venturi tube, spray pipe, strutting piece, build-up welding layer, down stop device, regulating sterm, go up stop device, the bleed pipe is the return bend structure, provides and is used for preventing intraductal gaseous sealing member from the regulating sterm leakage drawing tracheal return bend structure department, the heavily stone roller and the regulating sterm that prevent the drop pass through welded connection, heavily cut or polish jade with an emery wheel upper portion and provide down stop device, provide stop device on the regulating sterm for prevent heavily that stone roller and regulating sterm install in the lower part of drawing tracheal return bend structure at the strutting piece of intraductal vibrations, and with the regulating sterm installation together. The device equipment investment is few, and purification efficiency is higher, the effects such as cooling, moisturize and purification hazardous gas of lowering the temperature in addition at the dust removal in-process, and dust removal effect can adjust according to gas flow and gaseous dustiness, and the rate of fault is low, long service life.