The invention relates to an apparatus for the pretreatment and subsequent conveying or plastification of plastics, with a container (1) with a mixing and/or communication implement (3) that is rotatable around an axis (10) of rotation, wherein, in a side wall (9), an aperture (8) is formed, through which the plastics material can be removed, a conveyor (5) being provided, with a screw (6), rotating in a housing (16). The invention is characterized in that the imaginary continuation of the longitudinal axis (15) of the conveyor (5) in a direction opposite to the direction (17) of conveying passes the axis (10) of rotation, there being, on the outflow side, an offset distance (18) between the longitudinal axis (15) and the radial (11) that is parallel to the longitudinal axis (15), and in that the diameter D of the container (1) has the following relationship to the diameter d of the screw (8): D = 10. 3 √ K.d2, Where D is the internal diameter in mm of the container (1) d is the diameter in mm of the screw (6) and k is a constant which is in the range from 60 to 180.