Dust free hot bituminous compound preparation - involves twin drums with aggregate and binder forming screen in hot gases

摘要

Bituminous compound prodn. by continuous process, with min. dust content, takes place with aggregate (20) and binder (21) entering a top revolving drum (1) and passing as a mixture to a bottom one (2). Heating gas flow from bottom drum to top one is effected via fixed housing components (6) which also form a runout chute for prepared compound (23), and gas deflection to the top drum takes place through the top part. Aggregate via the input chute, and binder constituents, are evenly distributed over the top drum cross-section, forming a veil, and gases led in with them deliver most of their heat content, any dust particles till free, and gaseous binder distillate to the mixture (22). Exhaust gases (27), completely devoid of these impurities, are carried away via the flue.