Investigation of the thermodynamic effects of lignite and biomass co-firing

This paper reviews the biomass and lignite cofiring project in a lignite fired Power Plant in Hungary. It is based on the referred BSc Thesis [4], in which it has been examined the behaviour of a single unit in a lignite fired power plant in case of different biomass/lignite mixture ratio. The object of the examination was to show how the basic features of the combustion change, especially the heat transfer relations, and the arising contaminants. The results show that most of the changes are caused by the much higher heating value of biomass. This means that in one hand less fuel is needed for the same performance, and the pollutant emission decreases. The higher temperature increases the ratio of radiation heat transfer. Theoretically it increases the NO_x formation as well, but was not examined since its complication.