Abstract: A process comprising the following steps: a) calcination of a metal carbonate by combustion of a fuel in the presence of a mixture of oxygen, water vapour and carbon dioxide, to generate a metal oxide, water vapour, carbon dioxide and heat; b) using the heat generated to drive an oxygen generation reaction; and c) use of the oxygen generated in step b) in calcination step a). The use of the process on carbon dioxide sequestration and/or in oxygen generation.

Abstract: Described is the use of a mineral comprising a metal carbonate fraction and a fuel fraction, such as oil shale or coal shale, in a calcination process. The disclosed process can advantageously result in carbon dioxide being removed from the atmosphere. Further, in the process, heat energy generated during calcination can be used to separate oxygen from air, so that the oxygen can be fed back into the system. Alternatively or in addition, heat energy may also be used to compress the gaseous carbon dioxide generated from the calcination process.

Abstract: A grid-energy firming process and a grid energy firming system. The process comprises alternating between a process for generating electrical energy, and a process for generating gaseous fuels in response to the energy demands of a grid energy system. The system comprises a reactor containing a carbonaceous fuel, and a heat exchanger to extract heat from the flue gas and/or gaseous fuel.

Abstract: A process and system for the generation gaseous fuels, the process comprising gasifying a carbonaceous fuel with vitiated air in the presence of lime and water to provide calcium carbonate, a gaseous fuel and heat; the system comprising a reactor for the gasification of the carbonaceous fuel with vitiated air in the presence of lime and water, and a heat exchanger to extract heat from the gaseous fuel. Use in the generation of gaseous fuels, in energy distribution and in grid energy firming.

Abstract: A process comprising the following steps: a) calcination of a metal carbonate by combustion of a fuel in the presence of a mixture of oxygen, water vapour and carbon dioxide, to generate a metal oxide, water vapour, carbon dioxide and heat; b) using the heat generated to drive an oxygen generation reaction; and c) use of the oxygen generated in step b) in calcination step a). The use of the process on carbon dioxide sequestration and/or in oxygen generation.

Abstract: An energy generation process comprising the oxidation of carbon monoxide to carbon dioxide in a fuel cell, the process comprising the step of producing the carbon monoxide from carbon dioxide and carbon and/or a hydrocarbon, and the step of producing the carbon dioxide from the calcination of a metal carbonate, together with an apparatus for use in energy generation comprising a calcination unit in fluid communication with the fuel cell and the use of the apparatus in energy generation.