NIRE Annual Report 1999

NIRE Annual Report

1999

Dry Separation of Polyvinyl Chloride from Plastic Mixtures Using Air Table

Minerals processing Division
Materials Processing Department

Objectives: The dry separation of polyvinyl chloride from plastic mixtures in municipal wastes is investigated using an air table which separates plastic mixtures into their components by the action of vibration and rising air flow. The objective of this investigation is to decrease the content of polyvinyl chloride in plastic mixtures to 1% or less by the dry separation process.

Results: Fig. 1 shows the air table used for the experiment. The major components of the equipment are a feed hopper, shaking deck, and air flow generator. A sample obtained by mixing 15% of polyvinyl chloride (PVC) and 85% of polyethylene (PE) is fed onto the shaking deck by the electromagnetic feeder. the influence of the frequency of the deck to be exercised on the PVC separation was examined.

Fig. 1. Air table used for the experiment.

Fig. 2 shows a relationship between the content of the PVC in a light product together with the recovery of the PE and the frequency of the deck, when the separation is made with the inclination angle 6.0 and average air velocity 0.92 m/s. Under the condition of the experiments, it is shown that the sharp separation was made when the frequency is 6.8Hz, the inclination angle of the deck is 6.0, and the air velocity is from 0.8 to 1.05 m/s. The recovery of the PE at that time was 99.6%, and the PVC contained 15.0% at first in the plastic mixture was successful in reducing to 0.44%.


Fig. 2.	Rwlationship between content of PVC in a light product together with recovery of PE and frequency of the deck.

National Institute for Resources and Environment

Dry Separation of Polyvinyl Chloride from Plastic Mixtures Using Air Table

Minerals processing DivisionMaterials Processing Department

Minerals processing Division
Materials Processing Department