On the Distributors and Design Criteria for Gas-Solid and, Gas-Liquid-Solid Fluidized Beds

Abstract

Fluidized beds are well known for their versatile applications in chemical, metallurgical, mineral and bio - processing industries. Inspite of their several potential uses, the design and selection of the fluidized bed reactor is still empirical. One of the key parts which influences the reactor performance is the distributor/grid which has been recognized as the heart of the fluidized system. Distributor also called grid in fluidized bed plays a vital role in assessing the hydrodynamics and performance of the reactor. Though the importance of the distributor has long since been recognized, not much seems to have been done on basics of its design aspects. In the context of significant developments that have taken place in the field in the last decade the need exists for a comprehensive review updating the available information on the role of distributors and their design for the fluid bed system. Hence a state-of-the-art review of a wide range of distributors/grids has been attempted in this paper and the need for careful consideration of the design principles is discussed. Prediction of operating flow rates as influenced by distributors, pressure drop criteria pertinent to stability of operation, the choice of grids or distributors and their types from laboratory scale to commrecial size units, design models and the role of plenum chamber and pumping requirements are all critically reviewed and analyzed. Nomographs for the distributor design and the scope for future research stressing the immediate needs are presented.

Additional information

Notes on contributors

A. VOGELPOHL

Institut fur Thermische Vefahrenstechnik, TU Clausthal, D - 3392 Clausthal - Zellerfeld, Germany.