Applicability of thermal energy storage recycled ceramics to high temperature and compressed air operating conditions

•ACW ceramics have been successfully tested under ACAES operating conditions.•ACW ceramics have been successfully tested under gas turbine based CSP conditions.•Under 600 °C-30 bars of air, ACW ceramics Cp is slightly lowered by 5%.•Thermal conductivity of ACW ceramics is advantageously enhanced by 30%.

Recycled ceramics made of inertized asbestos containing wastes have been submitted to high pressure/temperature cycling tests in the operating range of ACAES and CSP applications. Ten successive cycles between room conditions and 610 °C/30 bars for a cumulated duration of 2500 h lead to a validation of the ability of the material to resist to those constrains. The Wollastonite/Augite initial structure is gradually transformed in a unique Augite containing material. While mechanical parameters and density are unchanged, thermal capacity is reduced by 5% and thermal conductivity increased by 30%. This last result offers an advantageous way to enhance the thermal conductivity of those recycled ceramics, a key parameter to control the charge/discharge power in TES systems.