New waste to energy (WtE) alternative: fuel gas production and power generation via gas engine

Management and disposal of municipal solid waste (MSW) is an important issue in waste-free cities. Although waste of energy (WtE) via incineration is widely adopted in the world, the emissions of pollutants from the MSW incinerators, especially the dioxin emissions in gaseous and solid phases are a serious problem. In addition, for MSW management in towns or small counties, the conventional WtE via incineration is not applicable due to the economic limitation. For years we have developed an alternative WtE technology, which is characterized by thermochemical processes including pyrolysis and reforming of volatiles afterwards, and finally fuel gas is obtained and cleaned to feed a gas engine for power generation. In the developed system all of the oil or tar from MSW pyrolysis is converted into gas by catalytic cracking over the char. The char acted as a catalyst, but it was also partially or entirely gasified simultaneously. The obtained fuel gas is cleaned before feeding the gas engine and also was used to warm the pyrolysis reactor. The dioxin emissions from the flue gas and partially gasified char were checked. The lower heat value (LHV) of the fuel gas as well as the energy recovering efficiency changes from waste to power were also investigated. The results supported the soundness of this newly developed technology.