Plastic recycling plants for polyolefines for which a pre-separation from heavy contamination like stones metal, glass etc. is required – as well as for the preparation of the recycling material for subsequent processing. The pre-wash drum may be used for films, bottles or thick-walled contaminated plastics. Normally the material is shredded and decomposed to a particle size of 50 – 100 mm before it is fed in the pre-wash drum.
Advantages of the Pre-Wash Drum
– Cost saving by prevention of damages to the downstream grinding and washing systems.
– Simple installation and integration into the recycling plant.
The pre-wash drum requires low maintenance and is insusceptible for disturbances. If required, the pre-wash drum is easy accessible for maintenance- and repair work.
Construction and Function of the Pre-Wash Drum
The pre-wash drum consists of a cylindrical separation level with material discharge as well as a conical feed hopper for the recycling material as well as the water. The rotation of the drum circulates the material which dissolves lumps to achieve an effective separation of rough contamination.
The complete unite is mounted in a slightly inclined position to allow the water to flow downwards.
The inside of the separating unit is a screw spiral construction, rough contamination is transported to the top, against the water flow for discharge, while the screw spiral flushes the water and the plastic to the bottom for discharge. In plastic recycling the pre-wash drum is utilized for separation- respectively for pre-separation purposes. The pre-wash drum separates the shredded plastic flakes from heavy contamination like stones, tire scrap and metals.
The pre-wash drum is driven by a three-phase motor. The complete unit is mounted to a
strong frame which is driven by solid rubber tires, which turn the drum in the requested rotation. This solid, simple and almost maintenance free drum is the main
advantage of this separation unit.
The pre-wash drum is completely manufactured in stainless steel. The solid rubber tires
offer the desired durability.