Keywords: lignite fired power plants, pressurised fluidised bed dryer, fuel cells, waste heat, lignite drying, power generation
Development of a lignite-fired power plant concept with integrated pressurised fluidised-bed drying and fuel cells
In the coming decades, lignite will become one of the most important fuels for power production in Germany. In the last five years, Vattenfall Europe and RWE have put power plants of the 800–1000 MW class with efficiency of up to more than 43% into service. Four to five per cent efficiency can further be gained by using pre-dried lignite as fuel (BOA plus concept of RWE). Additional steps are possible if the lignite-drying process and combustion are operated under pressure. This paper describes the first steps based on the A.M. technology whereby the waste heat of fuel cells is used for operation of the lignite dryer to achieve highest efficiency levels.