Carbonisation as a pre-treatment for rdf wastes prior to gasification

The present work is intended to evaluate carbonisation as a pre-treatment for heterogeneous wastes containing polymeric fractions, before their gasification for energy production. Carbonisation had an upgrading effect in the raw wastes by yielding chars with higher apparent density and an improved behaviour during feeding operations. The performance of the gasification process was compared for the raw wastes and the corresponding biochars. The results obtained indicate that carbonisation helped to improve this performance by increasing the calorific value of syngas, and the process efficiency. Gasification of the chars produced less tars and gaseous HCl which is a positive effect concerning maintenance operations and overall costs. Therefore, the carbonisation pre-treatment can be seen as a valid option to be integrated in a gasification process to convert wastes into energy especially for low density wastes with high chlorine contents.