ABSTRACT
Non-plasma gasification and pyrolysis technologies for the utilisation of waste are introduced. A detailed description of the potential benefit of using gasification or pyrolysis compared to combustion is given. Two exemplar cases of thermal gasification technology are presented. The first case is a large-scale fluidized-bed gasification of refuse-derived fuel in Lahti, Finland, which uses the waste collected from a radius of 200 km. A considerable higher electricity efficiency (than the standard waste energy plant) is attained by first gasifying the waste, then using high-temperature removal of solids and chlorine alkali compounds from the produced calorific gas, and finally combusting the cleaned gas with the production of steam of higher temperature and pressure than with standard waste energy combustion-based facility, which leads to a substantially higher efficiency of electricity production. The second case is a small-scale technology which is designed to be able to process waste from a medium agglomeration and that uses gasification in order to have better control within the combustion process. Finally, the possible development of gasification and pyrolysis technologies is discussed. One of the prospective ways is to produce concentrated and cleaned syngas (H2+CO) for the synthesis of chemicals or alternative fuels. For this purpose, thermal plasma-assisted gasification and pyrolysis can be promising.
