Themodynamic Analysis And Experimental Research On Solid-Gas Reaction Heat Transformer

The solid-gas reaction heat transformer, which can upgrade the temperature of middle-grade heat reservoir (such as industrial waste heat, solar energy, geothermal energy, etc) is considered promising for energy-saving in the near future. It realizes temperature lift through the synthesis and decomposition solid-gas reactions at different temperatures corresponding to different pressures. As compared to other heat transformers, it provides high storage capacity of heat, wide range of working temperatures, long-time storage of reactants and products, low heat loss, and etc. In addition, it uses all natural working pairs, which are friendly to the environment. Unfortunately, for its complicated chemical kinetics, high requirement for safety, low system efficiency, large investment, etc, it has not been widely used yet.This paper analyzes the thermodynamic performance of different kinds of one-stage and two-stage cycles to find out the best cycle for certain design requirements. Temperature lift curves under different temperature of input heat are obtained from the small experimental application and the specific heat power (SHP) is calculated, so that the feasibility of the solid-gas heat transformer is validated. Besides, the impact of different filling states on the system performance is also discussed. Then the physical model and mathematical model which contains the energy balance equation, reactive rate equation and equilibrium equation of solid-gas reaction as well as the state equation for ideal gas are established to simulate the temperature change in the reactor, and the simulation results are well consistent with the experimental ones. Last exergy-economic analysis is carried out on the irreversible quasi-four-heat-reservoir model of one-stage solid-gas heat transformer. The effects of some important influential factors are discussed in terms of numerical calculation and the variations of some important performance parameters with the temperature of working fluids are studied, so as to determine the optimal operating region. These theoretical and experimental results will be helpful to the establishment of large solid-gas reaction heat transformers.