Thermodynamic study of a new thermochemical cycle for the hydrogen production powered by different thermal sources

Abstract

The present study aims to investigating and simulating a hydrogen cycle production at low temperatures using thermochemical reactions. The cycle used in this work is based on the dissociation of water molecules depending on a copper-chlorine couple (Cu-Cl). Furthermore, the proposed method uses mainly thermal energy provided by a turbine exhaust. This proposed cycle differs from what is found in the literature. However, most of the thermochemical cycles for hydrogen production work at quite high temperature which is a technical challenge. Therefore, the maximum temperature used in the present cycle is limited to 500 °C. A thermodynamic analysis based on both first and second laws is performed to evaluate the energy, exergy, and efficiency of each reaction and the overall exergetic efficiency of the system. Furthermore, a parametric study is conducted to figure out the impact of the surrounding temperatures on the overall exergetic efficiency using the energy simulation software EES. The results show that the cycle can achieve an exergy efficiency of 30.5%. the quantity of hydrogen and oxygen produced from this cycle was calculated for this cycle after connecting the hydrogen production unit with a thermal power plant producing electricity with gas turbines at Hassi R'mel. Keywords Hydrogen production; thermochemical process; Copper-Chlorine cycle; water dissociate; exergy and energy analyses.