Solar thermochemical energy storage in elemental sulphur: design, development and con-struction of a lab-scale sulphuric acid splitting reactor powered by hot ceramic particles

Abstract

A proof of concept sulphuric acid splitting/decomposition prototype driven by hot bauxite particles is designed and developed. The lab-scale test reactor is a novel counter-current flow shell-and-tube heat exchanger with particles on the shell side and sulphuric acid on the tube side with mass flow rates of 10 kg/h and 2 kg/h, respectively. A one-dimensional heat transfer model was developed based on correlations of the flow boiling heat transfer coefficient and particle bed heat transfer coefficient for sizing the shell-and-tube heat exchanger. A detailed study was carried out in order to choose suitable materials especially in the sulphuric acid inlet and evaporation section. A new concept of an electrically heated, continuously operated particle heating system was designed and developed to provide the splitting reactor with hot particles. Different cases were studied using a finite element method (FEM) analysis to qualify the particle heater and examine its thermo-mechanical stability