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Posted: Jun 19, 2017
Next-gen solvents capture carbon with half the energy
(Nanowerk News) U.S. energy production could increase with the help of an improved carbon capture technology that use about half the energy of today's standard technologies. Emissions captured at fossil fuel power plants could in turn be used to harvest more crude by injecting it into underground oil fields.
Pacific Northwest National Laboratory scientist David Heldebrant captures sulfur and carbon dioxide from test emission streams in a process called Reversible Acid Gas Capture.
There are a few carbon capture plants in operation today, and all of them rely on water-based solvents that also carry nitrogen-rich compounds called amines. These standard carbon-capture solvents are skilled at capturing carbon, but require a great deal of heat to recycle the solvents, a process called regeneration. The solvents must be exposed to high temperatures to undo the bonds between solvent and carbon. Using that heat makes power plants less efficient and ups the price tag of energy generated at power plants.
Water-lean solvents were designed to make the overall carbon-capture process more energy-efficient. They can break carbon out of used solvents at lower temperatures, which means they can be regenerated with colder waste heat from power plants instead of tapping the more valuable, hot steam that plants normally use to generate electricity.
The paper's comprehensive review of existing research on these next-generation solvents found the technology pulls out enough carbon from power plant emissions to make it cost-effective and that it requires half as much energy as traditional solvents.