Electrochemical carbon cleaning
26 Jun 2013
Researchers at MIT have developed a method that ’scrubs’ the harmful emissions generated from fossil-fuel power plants.
Current techniques rely on complex plumbing to divert the steam used to drive the turbines - but such systems are impractical as retrofits to existing plants.
Experts at the Massachusetts Institute of Technology (MIT) have devised a scrubbing system that does not require a steam connection, is operable at lower temperatures and would effectively be classed as a ’plug and play’ solution that can be added to existing power plants.
“An electrode forces the release of the gases and the amine molecules are then reused
The electrochemical technique, as described in the online journal Energy and Environmental Science, is a variation on a technology which uses amines, a chemical compound that combines with CO2 and releases the gas when heated in a separate chamber.
The amine based system injects a solution at the top of an absorption column which then binds with the CO2 in the emissions stream and is collected in liquid form at the bottom of the process.
A metal electrode electrochemically forces the release of the hazardous gases and the amine molecules are then regenerated and reused.
The researchers believe their thermal-amine scrubber system is capable of removing up to 90% of CO2 produced from a plant’s emissions, using as little as 25% of the power output required by conventional processes.
David Heldebrant, senior research scientist at the Pacific Northwest National Laboratory, suggested: “As with any process, the main questions and uncertainty pertain to the costs and lifetime of the system.”
His team’s system, however, is applicable across a wider range of applications as it does not rely on steam from a boiler.
Heldebrant believes the amine-based system could be used in cement factories and could also help reduce the amount of emissions produced in steel and aluminium works.
