Carbon capture and storage (CCS), also referred to as carbon capture, utilisation and storage (CCUS) is taking shape as an important tool to lower greenhouse gas emissions. As CCS solutions are being developed and applied, the hoped-for result will be a smoother way as we make the transition to cleaner energy.
A good number of large-scale projects are already at work capturing carbon dioxide (CO2) at industrial and power-generation sites, so continued R&D should aid in streamlining processes and lowering costs.
The recent technology development agreement signed by ExxonMobil and Global Thermostat aims to further advance capture of CO2 emissions from industry as well as directly from the atmosphere. Global Thermostat operates a pilot plant at SRI International, an R&D, an advanced R&D centre, to test its technology, and ExxonMobil’s role will be to support and evaluate the technology’s scalability for use on an industrial scale.
While amine technology has been in use since the 1930’s to separate CO2 from natural gas, scalability testing has been underway at TCM and around the globe for nearly a decade.
The Global Thermostat proprietary amine process uses “dry” amine-based chemical “sorbents”. These are bonded to “monoliths” of porous, honeycomb ceramic and act as “carbon sponges”. The captured CO2 is removed and collected using low-temperature steam.
From thin air
Industrial applications offer real hope in mitigating carbon dioxide release from industry, before it can enter the atmosphere. But the both Global Thermostat and Carbon Engineering, based in Canada, foresee their processes being put to use on the atmosphere itself. Direct Air Capture (DAC) offers an additional tool to meet global climate goals.
Carbon Engineering’s DAC makes use of an alternative capture option, using a “strong hydroxide solution” that binds with CO2 and converts it into carbonate. The carbonate is processed into calcium carbonate pellets, which are heated to release the pure CO2, and the solids left behind – lime or calcium oxide – are reused in the formation of new pellets.
In June, the Canadian government showed its support, providing CAD 25 million in funding to Carbon Engineering for continued R&D and design of full-scale plants.
In the past, the most common use for captured CO2 has been to inject the gas to increase oil field pressure, thus increasing oil recovery. More recently, sequestration in geological formations has also been practiced, such as with the Sleipner CCS project, offshore Norway.
Captured carbon dioxide’s potential worth in manufacturing or as a fuel feed stock of the will be a benefit as well – something to keep an eye on.