Research is active on the patented technology, titled "Apparatus and Process for the Separation of Gases Using Supersonic Expansion and Oblique Shock Wave Compression.” This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.
The separation of a gaseous mixture into constituent gases has proven to be useful for a variety of industrial and commercial applications. Currently CO2 can be separated from multi-component gas streams using compression and refrigeration techniques in order to condense the CO2 out of a vapor phase so that it can be mechanically separated from the stream. These techniques require a significant amount of energy expenditure, as well as, additional system complexity.
This patent-pending invention addresses the above issues by applying two aerodynamic techniques that both cool the gas and change the phase of the CO2 component from a vapor into a solid so that it may be mechanically separated from the stream.
The method first pressurizes the multi-component gas stream to the point where it may be accelerated to a supersonic speed through a converging-diverging nozzle. This process cools the gas stream without refrigeration to the point where CO2 changes phase from a vapor to a solid thereby eliminating the need for an energy-intensive compression and refrigeration cycle. After this expansion, the gas is in a supersonic state and is passed through a series of oblique shock waves. These shock waves gently increase the pressure and temperature of the mixture such that CO2 remains in a solid state while the other components stay in a gas phase.
Since the invention has been shown to be useful to separate CO2 from a multi-component gas stream, it has potential for future application in any fossil fuel burning power generation system where CO2 gas is generated as a by-product.
U.S. Patent No: 8,771,401
Title: Apparatus and Process for the Separation of Gases Using Supersonic Expansion and Oblique Wave Compression
Inventors: John VanOsdol
NETL Reference No: 10N-06