is it possible to burn a higher quality coal in a lignite fired boiler? will there be any impact in efficiencies? i understand the reverse may not be true viz. lignite cannot be burned in an anthracite fired boiler.
There are several drawbacks. One is the coal mills are set up for a particular type of coal, they may have to re-worked to process a much harder coal like anthracite. Also, if the boiler is designed for a lower heating value coal like lignite, the heat exchange surfaces may not be optimized for a high heat value coal like anthracite. There may be too much heat release in the water tube section and not enough heat going to the steam section. The amount of ash also affects the heat absorption in the same manner, since the anthracite will probably have less ash than lignite. This will affect the efficiency of the boiler.
