Pollutant separation from bituminous mixt. - uses solids to form movable filling of gas filter in drum drier

摘要

The process separates dusty or gaseous pollutants from a mixture of solids and bituminous binder during treatment in a drum drier. The gases containing the pollutants are passed through a conventional laminated filter, containing fibrous or granular material. At regular intervals the filter is cleaned by shaking and/or wet flushing until a preset lower flow resistance is reached. The loose material used to fill the filter (7) is part of the granular solids subsequently used to produce the mixture. The cleaning effect is produced by the solids rolling and sliding by gravity. The lower flow resistance through the filter layer (11) is determined by their packing, in conjunction with the speed at which they flow through it. The flow is halted as long as the flow resistance to the gases through the filter is below an adjustable, preset value.