3.3. Improvement of separation for actual floatable PPW films in a wet
gravity separation
The wet gravity separation was applied to actual light PPW
films and the improvement in removal of CP films by ozonation
method was investigated. The actual light PPW films were found
floating on the surface without mixing and the composition of
films is shown in Table 1. After a simple mixing of 2 min nearly
6.3% of total PPW films was able to settle at the bottom and it
was found there is no change in CP films during the period of study.
After ozonation followed by 2 min of mixing time, the recovery of
PPW films as floated films has been found to be 90% and no change
in CP films was observed. The entrapment of air cannot be removed
in CP films. The percentage of floated fraction in other films (PS and
PA) was also found to be decreased by ozonation. The combination
of ozonation and wet gravity separation process can be useful for
the recovery of PP and PE films with high purity from CP films.