Inductively heated fluidized beds and their potential for energy savings and efficient process control

This article presents a novel method with the necessary equipment for introducing contactless energy into heated fluidized beds, enabling improved energy utilization and consistent quality of the manufactured product. Inductive energy input serves as an alternative to convective heating. In contrast to conventional heat supply, where the heated fluidization gas acts as the energy carrier, electrically conductive particles are used here. These electrically conductive, yet chemically inert particles, are introduced into the fluidized bed and fluidized together with the substrate to be treated. An integrated inductor within the system applies an electromagnetic alternating field to the fluidized bed, thus inductively heating it. The heated inert particles are intended to release their heat from the interior of the fluidized bed over a very large surface area to the material being treated. This results in a high energy density and, ultimately, highly efficient heat transfer. This is especially relevant for batch processes that are evaluated for efficiency and cost-effectiveness. The fast and precise temperature control in inductively heated fluidized beds is also particularly beneficial for thermolabile materials.