Revolving drum mixer for bitumen road surfacing - uses offset burner paddle wheel with segmental end walls to reduce dust and fumes

摘要

The plant uses two superimposed revolving (R) drums (A,B) on horizontal axes (a,b) for the drying and coating of raw aggregates with cold bitumen, producing hot bituminous macadams for highways. The drum axes (a,b) converge through definite inclination to the horizontal, measures being incorporated to reduce the prodn. of dust and noxious vapours. The measures may have a revolving paddle wheel (21), an offset burner (22), and segmental drum end walls (18,19,20). The wheel is sited bythe ascending drum sectors, to alleviate the concentration of material and to redistribute concentrate in the descending sectors (C). The burner (22) is sited to treat material concentration, the end walls (18-20) deflecting the burning gases.