Fluidized Beds

The traditional importance of heat and mass transfer in physics and engineering have led to many physical interesting and mathematically challenging problems in relation to nonlinear parabolic and hyperbolic equations. From the process engineering point of view, the fabrication and subsequent treatment of disperse products are very important. This is due to the fact that 60% of all products of the chemical industry are particles.The work is on the modeling of heat and mass transfer in gas-solid-fluidized beds with spray injection which are widely used for the formation of particles from liquid solutions or suspensions as well as for the coating of particles with solid layers for the production of functional surfaces to enhance their handling properties, e.g. instant properties, controlled release or protection for chemical reactions.
Such a fluidized bed spray granulation (FBSG) system involves high heat and mass transfer and mixing properties, as well as the coupling of wetting, drying, particle enlargement, homogenization and separation processes. In FBSG, the liquid is sprayed with a nozzle as droplets on solid particles. The droplets are deposited on the particles and distributed through spreading. The solvent evaporates in the hot, unsaturated fluidization gas, thereby the solid grows in layers on the particle surface. This process is called granulation or layering (coating). The process conditions in the injection zone have a strong influence on the local particle volume concentrations, particle velocities, deposition of the liquid droplets and solidfication of the solid content of the liquid and subsequent product qualitiy. Fluidized beds are widely used to achieve either chemical reactions or physical processing that require interfacial contact between gas and particles. Heat transfer is important in many of these applications, either to obtain energy transfer between the solid and gas phases or to obtain energy transfer between the two-phase mixture and a heating/cooling medium.The latter case is particularly important for fluidized bed reactors which require heat addition or extraction in order to achieve thermal control with heats of reaction. The project aims to compute balance laws for fluidized beds with discontinuous Galerkin methods.