INFLUENCE OF TEMPERATURE ON THE PRODUCTS OBTAINED IN PYROLYSIS OF WASTE PACKING AND PACKAGING PLASTICS

摘要

The objective of this work is the study of pyrolysis as a feedstock recycling process, for valorising the rejected streams that come from industrial plants, where packing and packaging wastes are classified and separated for their subsequent mechanical recycling. A representative sample of these rejected streams has been pyrolysed under nitrogen in a 3,5 dm3 autoclave at 460, 500 and 600℃ for 30 minutes to analyze the influence of temperature in the products obtained. Waste packing pyrolysis liquids are a complex mixture of organic compounds containing valuable chemicals as styrene, ethyl-benzene, toluene, etc. Pyrolysis gases are mainly composed of hydrocarbons together with some CO and CO2, and have very high gross calorific values (GCV). Almost no solids are obtained in pyrolysis of waste packing plastics.Temperature plays a significant role in the pyrolysis process. At 460℃ total conversion of the waste plastics is achieved. Raising temperature gives rise ti higher gas yields and lower liquid yields. The characteristics of pyrolysis products, especially the liquid fraction, vary significantly with temperature. At 460℃ wax-like products are obtained, at 500℃ high viscosity liquids and at 600℃ more fluid and aromatic liquids are obtained.