Modeling of gas-solid chemisorption in chemical heat pumps

A model coupled the chemical kinetics with heat transfer was applied for simulation of the dynamic behavior of the gas-solid fixed-bed reactors used in chemical heat pumps (CHP). The kinetic parameters and the thermal parameters were identified, respectively. Good agreement was found between the simulation and the experimental data. Moreover, the sensitivity of the global advancements and the radial temperature profiles to the thermal parameters was analyzed. The thermal capacity of the reactive medium has little influence on the global advancement, while the effective thermal conductivity of the medium has an apparent effect on the global advancement. The influence of the effective thermal conductivity on the global advancement is significant until its value is larger than 15 W m(-1) K-1. The contact heat transfer coefficient between reactive salt and reactor wall has less influence on the global advancements and the radial temperature profiles when its value is higher than 800 W m(-2) K-1. This model can be used for optimal design of CHPs, optimization of the operation conditions, and determination of the influence of various parameters on the reactor performances, including the kinetic and thermal parameters, the operational parameters (imposed pressure and temperature), and the configuration parameters of the medium or reactor (geometry and dimensions). (C) 2003 Elsevier B.V. All rights reserved.