Fluidised bed biomass combustion

Increasingly , biomass is being used as replacement fuel for fossil fuels. This bring along with the change problems associated with agglomeration and deposition due to the chemical composition of the ash produced. In a fluidised bed system, this can manifest itself in the form of deposits growth in freeboard regions that can then fall to the bed and cause defluidisation. This can , in turn, cause local hot spots to develop with further nucleation and growth of in-bed agglomerates which can exacerbate the problem. Ultimately, if the problem cannot be prevented or resolved by intervention then a plant shut-down would occur. In order to avoid this problem strict control of operating conditions is required and a knowledge of flue gas flows through the combustor.

This project will be both experimental and computational in nature. the experiments will be carried out on a pilot plant fluidised bed (LCCC) which will be the basic system for the preliminary model validation. Subsequently, the model will be applied to an industrial partner power plant which is a full size fluidised bed combustor.

Outcomes will take the form of elucidation of agglomerate formation mechanisms and optimised fluid flow models in the combustor.