Abstract: The device comprises a drum drier with parallel streams (1) fed with recycled materials and a drum drier and countercurrent mixer (2) fed with virgin aggregates at its entry end (2a). The exit end (1b) of the drum with parallel streams (1) through which the dried and preheated recycled materials leave is connected to a ring (26) for introducing materials through the side wall of the countercurrent drum (2) through a chute for transferring the recycled materials. The ring (26) for introducing the recycled materials opens into a recycling and mixing zone (23) situated in the countercurrent drum (2) around the body of the burner (10), between the flame zone (22) and the mixing zone (24). The dried and heated recycled materials (8) are transferred continuously into the recycling zone (23) of the countercurrent drum (2).
Abstract: The drying/coating drum comprising a burner (20) whose body (19) penetrates via the discharge end (3) of the drum into a zone which is distant from this end. The gases and the solid materials circulate countercurrent-wise in the drum. The body (19) of the burner (20), fixed relative to the drum (1), is disposed inside an outer peripheral sleeve (22) which is free in rotation about the body (19) of the burner (20). The outer sleeve (22) is connected to the casing (1) of the drum. The end of the outer sleeve (22) corresponding to the end (19a) of the burner from which the flame (14) develops carries a plurality of radially directed blades (25, 26) forming a turbine for sucking gas into the mixing zone (30) and a screen against radiation from the flame (14) of the burner (20) during rotation of the drum.
Abstract: A mixer (10) consisting of a stationary casing (9), into which the outlet end (2b) of a rotary drum (2) opens, and mixing vanes fixed to the casing of the drum (2) and extending this casing axially in the direction of its outlet (2b). A burner (13) having an elongate body (12) projects into the drum (2) at its outlet end (2b) and opens into a flame zone (22). A recycling ring (32) is arranged around the drum (2) in the vicinity of the end (12a) of a burner. The casing (9) of the mixer delimits a mixing zone (36), separate from the flame zone (22), around the body (12) of the burner.
Abstract: A burner (13) and a conveyor (6) for aggregates (7) into the drum (2) penetrate into the drum at opposite ends (2a, 2b). Circulation of the gases inside the drum occurs in direction opposite to circulation of the aggregates. The burner has an elongated body (12) arranged in the axial direction of the drum. The drum comprises, from the inlet end (2a) to the outlet end (2b), a drying zone (21), a flame zone (22), a zone for introducing recycled mixes (23') and a heating and mixing zone (23). The device may be associated with a mixer (42) of the conventional type in which the bituminous products (11) leaving the drum (2) are mixed with liquid bitumen and worked. The invention enables coated products for road surfaces to be prepared without the production of bitumen vapor.
Abstract: The solid materials circulating inside the drum are raised between a zone (22) in which the flame of the burner (12) is produced and a mixing zone (30) by raising vanes (18, 18') which form a dense screen of materials isolating the mixing zone (30) from the flame zone (22) as a result of the solid materials being raised and falling back down when the drum (2) is rotated. Recycled materials may be introduced into the zone (23) where the dense screen is formed.