Gasification process of wastes containing PVC

Solid waste, in dealing with the growing presence of organic compounds, especially plastics, can be considered an important source of energy since they are inexpensive and easily obtainable materials. However, the presence of polyvinyl chloride (PVC) in the waste can result in a recycling problem when thermal treatment is involved. This work shows the possibilities of recovering energy from waste containing PVC by a gasification process without additional dechlorination facilities. Experimental data obtained in a bench scale two-stage reactor indicate that the addition of Na2CO3 in a blend containing refuse-derived fuel (RDF) and PVC is efficient in eliminating chlorine from the produced off-gas. On the contrary, the less expensive calcium compounds do not show a satisfactory chlorine removal. A thermodynamic simulation of the process substantially leads to the same results. Starting from this study, the working conditions for gasifying waste blends containing PVC in a scaled-up two-stage reactor can be predicted. According to the simulation, the obtained syngas shows that the polluting compounds content is lower than the Italian law limit. As a consequence, it can be used directly to obtain electric power and/or local heating