Design of thermochemical heat transformer for waste heat recovery: Methodology for reactive pairs screening and dynamic aspect consideration.

Waste Heat Recovery in the industrial sector often requires to upgrade the temperature of the heat fluxes in order to make them useful for the process. Thermochemical Heat Transformer (THT) and especially 2-salt configuration, can play a major role as they can achieve high temperature lift when compared to alternative technologies. Despite various developments in recent years, this technology still suffers from several issues to make it fully attractive: rapid and reliable reactive salt selection, heat and mas transfer intensification, coupling with process heat demand, etc. This work is focused on a new methodology to achieve a rapid screening of salt pairs for a given application (i.e. source temperatures). Four criteria, based on thermodynamic considerations, are proposed allowing for an example to go from 4290 possibilities to only three most promising pairs at the end. A second part is dedicated to dynamic aspect considerations, exploring the robustness of the solution towards changes in heat transfer and kinetic coefficients as well as to changes in heat source temperatures. Knowledge on this last aspect is of great importance to achieve efficient integration to cover process heat demand. • A new methodology to achieve a screening of salt pairs for 2-salt THT is developped • 3 promising reactive pairs from 4290 candidates are selected. • A 0D dynamic model of 2-salts THT is developed and validated. • The relation between the driving forces and the THT heat power is highlighted. [ABSTRACT FROM AUTHOR]