Abstract: An apparatus for bitumen coating particulate material comprises a chamber (2) having baffles or deflectors (4), a particulate material inlet (8) and a particulate material outlet (10). In use, a foamed bituminus formulation is directed into the chamber via an outlet (12) and an air stream is directed from an inlet (14) towards the bituminous formulation, to atomise the formulation. The atomised formulation then contacts particulate material which passes in a convoluted path through the chamber via inlet (8). Prior to contact with the atomised bituminous formulation, heated air which passes into the chamber via a second gas inlet (16) heats the surface of the stone. After the particulate material has been coated it is discharged via outlet (10) for subsequent use.
Abstract: A method of producing a bituminous foam includes supplying a bitumen in water emulsion from a tank (2) into primary and secondary heating circuits (8, 34), whereby the emulsion is heated (via heating coils 12 and 12′) and its pressure raised such that, on discharge to ambient conditions via outlet pipes (30 or 30′), the emulsion foams as water evaporates therefrom.