Tech Talk: Plastic Reclamation
A recent technical memo from our applications engineering department describes the reclamation process:
A washer soaks and agitates the plastic to loosen the labels and reduce them to pulp (maybe through the use of a caustic). They then drain and dump the wet solids into a sink/ float tank to float PE and sink PP (bottle cap) in water. Tank has shallow slope at one end with a short auger that lifts (and drains) the PE onto a two-deck 48" Kason (capacity 2000 lb/h wet PE) and a steep slope at other end with long auger that dredges the PP from the bottom up and onto another 48" Kason. A Kascade serving the overs deck boosts. capacity to 3000-4000 lb /h.
Each screener has a circular shower on each top deck to
1) re-pulp and rinse the plastic overs and
2) to drain the unders (plastic fines and paper pulp ) for disposal.
The 60- to 120-mesh water recycles as make-up.
The overs are so clean, the Spin Dryer runs two weeks without interruption for cleaning and its product is clean. Before rinsing on the Kason, the Spinner needed cleaning twice or more daily and its product was not as clean despite using more showers in the spin dryer .
This application was pre-tested by Kason application engineers so that our customer could determine both equipment needs and maintenance schedules before setting up the reclamation operation.
Flow Chart illustrates the varied applications of the Kason VIBROSCREEN in a plastic reclamation plant.
Screen Tips - Volume 12, Number 2 Fall 1997