DEVICE AND METHOD FOR TREATING PLASTIC MATERIAL

摘要

The invention relates to a method for treating plastic material, especially polyethylene terephthalate, wherein the relatively low temperature material is initially crystallized by heating before subjecting said material to heating or condensation in the solid phase. The material is then exposed to a hot treatment gas for at least 10 minutes in at least two chambers (2) of an apparatus and crystallized at a temperature above 135~ C, e.g. 140-180~ C. T he material is subsequently heated in a preheating chamber (3) having at least one to eight stages at a temperature of at least 185~ C, preferably at least 200~ C and more preferably around 220~ C.