Thermal Energy Storage Materials Made of Natural and Recycled Resources for CSP in West Africa

Abstract

A sustainable development of Concentrating Solar Power plants can be really undertaken by using locally made components and low cost eco-materials. This study is focused on the use of coal bottom ash from Niger coal power plant and slaked lime from Burkina Faso acetylene production as industrial wastes, as well as laterite and clay from Burkina Faso as natural stones for the elaboration of thermal storage materials. The various materials have been used directly or combined together to obtain a suitable mixture. In order to determine the effect of heat treatment on the materials obtained, their structural organisation, microstructure, chemical composition and thermal behaviours were investigated. The results showed that after heat treatment of the laterite, the iron-spinel phase with inclusion of repetitive dendrites of the magnetite phase was obtained. The bottom ashes have highlighted the possibility to elaborate mullite refractory ceramic after heat treatment. The results also showed that anorthite ceramic can be synthesized from the mixtures of bottom ash with slaked lime and laterite. The obtained materials showed good thermal behaviour. Therefore, the main benefits of these materials are their sustainable character, wide availability, relevance to thermal energy storage applications up to 900 °C, and absence of use conflict.