Abstract: In the preparation and production of plastic materials by a continuously operating double shaft screw-type extruder, the efficiency of production often depends on good delivery of material to the extruder. In accordance with the invention for processing various types of plastic materials, a primary stage is mounted in a pressure-tight sealed manner on the housing of the extruder, the primary stage being formed by a vertical double conical container in which a pair of screw-type helices are rotatably supported and driven from above. The helices are connected to two replaceable feed elements at their lower ends so that delivery of material to the extruder is achieved without any intermediate dead spaces.

Abstract: A mixing and processing apparatus for plastic melt is equipped with a separately drivable gear pump as a delivery unit. In order to avoid material deposits between the mixing and processing apparatus and the delivery pump, the gear pump is directly mounted at the outlet end of the mixing and processing apparatus, such as an extruder, so that the plastic melt is directly fed axially into the suction space of the gear pump. Cleaning operations after shutdown or in the case of change of material are eliminated due to this direct transfer without dead space.

Abstract: Radioactive waste concentrates encapsulated into non-deformable asphalt at the inlet of an extruder feeding hard asphalt granules and hydrocarbon oil for mixing therein and downstream of the initial mixing adding the radioactive waste concentrates for mixing with the initial mixture.

Abstract: A method and device for filling containers with evaporated radioactive waste concentrates that are mixed with bitumen and from which the water has been expelled by creation of temperatures above the boiling point of water, in which the temperature of the waste mixture is substantially reduced below the water expelling temperature immediately before loading the mixture into the containers.