Experimental investigation on heat transfer in a gas-solid fluidized bed with a bundle of heat exchanging tubes

Abstract

A fluidized bed reactor is commonly used for highly exothermic reactions for different chemical industrial processes. However, inefficient removal of the generated heat due to the exothermic reaction can seriously influence reactor performance. Hence, quantifying and understanding the heat transfer phenomena in this reactor is essential to enhance the performance of the reactor and consequently the chemical process. To achieve a better quantification and understanding of the heat transport in this reactor, an advanced heat transfer technique has been used in this study to quantify the impact of the presence of the cooling tubes on the local heat transfer coefficient under different operating conditions for this reactor. It has been found that the local heat transfer coefficient in the fluidized bed reactor equipped with a bundle of vertical tubes increases significantly as superficial gas velocity increases at the wall region, while different behavior was noticed at the center of the reactor. Moreover, the results show that the local heat transfer significantly decreases at the reactor's core region for all studied superficial gas velocities. Furthermore, the new tube arrangement offers a uniform local heat transfer profile for all studied operating conditions. The obtained new high-quality experimental data for the local heat transfer coefficient in a fluidized bed reactor equipped with a bundle of tubes can be used for validation CFD simulations or mathematical models, facilitating the design, scale up, and operation of this reactor.