Mixing device, mixing hopper and dosing container

A mixing system for mixing a synthetic starting material with a granular additive or additive in powder form, comprising a dosing container, a mixing hopper and a mixing device,

• wherein said dosing container comprises a space bounded by a container wall for containing a supply of said starting material, which space is in air-exchanging communication with a surrounding atmosphere via an air filter,
• wherein the dosing container is provided with measuring means which are able and configured to measure a weight change in the container,
• wherein the dosing container further comprises aerating means which are able and configured to allow air into said space of the dosing container when a quantity of said starting material is drawn out of the dosing container, thereby preventing an under pressure to occur in said space when a said quantity of said starting material is drawn out of the dosing container,
• wherein said mixing hopper is open on an infeed side in order to receive a flow of said starting material from said dosing container,
• wherein said mixing hopper is open on an outfeed side in order to discharge said starting material to a mixing housing of said mixing device,
• wherein a dividing body is provided between the infeed side and outfeed side of the mixing hopper in order to divide the flow of said starting material and said additive into a number of at least substantially equal part-flows,
• wherein a rotatable stirring body is provided between the dividing body and the outfeed side of the mixing hopper which is able to rotate through the part-flows with a stirring part in a plane transversely of a flow direction of said starting material,
• wherein said mixing housing of said mixing device has an inlet for allowing said starting material and an additive into a mixing chamber bounded by the mixing housing,
• wherein said mixing housing of said mixing device has an outlet for discharging the starting material and the additive from the mixing chamber in mixed form,
• wherein a rotor body is provided on a rotatable shaft in the mixing chamber, said rotor body comprising on a side a set of rotor arms extending parallel to the shaft in the direction of a facing wall of the mixing housing, and
• wherein the facing wall of the mixing housing is provided with a set of stator arms extending parallel to the shaft in the direction of the rotor body.