REVIEW pubs.acs.org/IECR
Heat Transfer in a Slurry Bubble Column Reactor: A Critical Overview A. K. Jhawar and A. Prakash* Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, Ontario, Canada N6A 5B9 ABSTRACT: Studies of heat transfer in slurry bubble column reactors have been reviewed and observed differences analyzed based on available data. Heat transfer in these reactors is a strong function of some parameters and a weak function of others. The parameters significantly influencing heat transfer in these reactors are the superficial gas velocity, thermophysical properties of liquid and solid particles, and size and concentration of the particles. Moreover, the rate of change with a parameter is dependent on the operating flow regime, particle properties, and presence of internals. Of all of the parameters, the effect of the particles is more complex and inadequately understood because particles influence the flow regime transition and thermophysical and rheological properties of the suspension, which, in turn, affect the hydrodynamic behavior and associated heat-transfer characteristics. The effects of the column diameter and internals have been investigated by a limited number of studies. A comparison of available data shows that the effect of the column diameter on heat transfer diminishes above 0.3 m. This, however, requires confirmation from larger-diameter studies together with associated hydrodynamic studies and appropriate modeling. Literature correlations for the heat-transfer coefficient have been reviewed and their limitations and applicability discussed. Axial and radial variations of heattransfer coefficients reported in literature studies require appropriate design considerations.
1. INTRODUCTION Applications of multiphase reactors are quite diverse, spanning a broad range from large-scale operations such as heavy oil upgrading to the manufacture of fine chemicals and pharmaceuticals. Literature studies have reviewed different types of multiphase reactors and their application areas.17 An important and growing area of application of multiphase reactor systems is the production of clean and renewable fuels such as the production of sulfur-free diesel by the FischerTropsch, dimethyl ether, and bioethanol processes. For a large number of these processes, there is a need for the proper design of the heat removal arrangement in these reactor systems to allow optimal temperature control for the desired product quality and yield. The reactor type commonly used for these applications is the three-phase gasliquidsolid reactor, wherein fine catalyst particles (
