Optimized heat exchanger integration within a TSA-process based on experimentally evaluated heat transfer correlations for finned-tubes in fluidized-beds

Abstract

In terms of design optimization of a potential heat exchanger within a gas-solid contacting stage, its thermal behaviours (i.e. heat transfer) is the key influencing factor. The aim of the work is to realize an optimized temperature swing adsorption (TSA) process system by heat exchanger surface configurations with finned tubes for fluidized bed. In a first step, the heat transfer coefficient (HTC) of Lewatit® VP OC 1065 will be experimentally investigated in a fluidized bed test system for the simulation of process characteristics of TSA. The HTC of four tubes with different circular helical fins was experimentally characterized as a function of variable fluidization gas velocities. All measurements were performed for single tube configuration resp. and staggered as well as in-line tube bundle configuration, respectively. The data obtained were validated to meet the energy balance and further used to develop a dimensionless correlation. After analysis and evaluation of the data acquired, the two developed correlations (i.e. single and bundle correlations) are able to predict heat transfer rates of finned tubes within a fluidized bed. These correlations are valid within a certain parameter range. In a second step, the correlations are integrated into a process simulation environment for dimensioning TSA-process systems. The simulation tool enables the calculation of the heat transfer rates of a gas-solid contact stage for adsorption or desorption. Hence, optimized heat exchanger surface layouts with finned tubes for fluidized bed TSA process systems can be realized.