Gas-to-gas heat recovery using fluidized bed technology

Abstract

The extraordinarily large surface area and heat capacity per unit volume of a bed of solid particles makes them attractive as a heat carrier. This paper reports briefly a theoretical and experimental study of some of the problems if the potential advantages are to be exploited. This revealed that the effectiveness of heat transfer from a hot gas to a flowing bed of solid particles could be estimated with sufficient accuracy, using known correlations for gas-to-particle heat-transfer coefficient and assuming that the particles flow in plug flow. The work also demonstrated that this type of system has a well-defined operating envelope, recording that of the flowing fluidized bed used in the experiments and indicating the parameters which affect it. Future development work required for industrial scale heat recovery systems based upon such principles is discussed.