Co-firing of pressed sugar beet pulp with coal in a laboratory-scale fluidised bed combustor

•Pressed pulp (71% moisture) has been successfully co-fired with coal.•Maximum pulp proportion in the blend for successful operation was 50%.•Effect of moisture can increase throughput of fluidised bed.•No agglomeration observed during extended co-firing tests.•NOx emissions were observed to be reduced during co-firing. Relatively cheap, poor quality, unprepared biomass materials can be difficult to burn efficiently on a large commercial scale because of their variable composition, relatively low calorific values and high moisture contents. Consequently it is often necessary to co-fire these materials with a hydrocarbon support fuel to ensure stable and efficient combustion. Fluidised bed combustion (FBC) is a promising method for burning mixtures of fuels with widely differing individual characteristics although there is a need for further information on the “optimum” conditions for efficient operation as well as on the proportions of support fuel which should be used in particular applications. This paper is therefore concerned with co-firing of coal with pressed sugar beet pulp, (a solid biomass with an average moisture content of 71%), in a lab scale (