Zero carbon solid-state rechargeable redox fuel for long duration and seasonal storage

This work presents a unique thermochemical process for charging magnesium-manganese-oxide-based solid-state rechargeable redox fuel. High-temperature heating of the processing furnace can be driven by either renewable electricity or concentrated solar power. The simple recyclable fuel charging concept is based on a tubular falling bed reactor with countercurrent oxygen-depleted gas flow for complete heat recuperation. The main focus of this work is achieving solid flowability at high temperatures (1,450 degrees C) and extracting chemically charged solid at ambient temperature with minimal energy loss. The operation strategies described in this work have enabled consistent magnesium-manganese-oxide particle flow up to 1,450 degrees C. The measured extent of the thermal reduction reaction after cooling the particles is more than 90% of the fully reduced state at equilibrium. The thermal-to-chemical efficiency and overall system efficiency are 96% and 35% respectively, which are the highest re-ported for thermochemical fuels to date.

Automated summary

This work presents a unique thermochemical process for charging magnesium-manganese-oxide-based solid-state rechargeable redox fuel. The high-temperature heating of the system can be driven by renewable electricity or concentrated solar power. The main focus of this work is achieving solid flowability at high temperatures and extracting chemically charged solid at ambient temperature with minimal energy loss. The operation strategies described in this work have achieved high system and thermal-to-chemical efficiency, which are the highest reported to date for thermochemical fuels.