This is actually huge. As I reported before, it is possible tooperate acid rain in a pipe to strip SOx and NOx from the flue gasstream, using the produced acids to reduce the heavy metals and runit all through a water quench to leave a pure CO2 feedstock for thestack. Now this technology easily grabs the CO2 itself. That was the only part missing.
It is now reasonable that all industrial thermal operations canachieve full stripping of the flue gases to produce acids, metalsalts and now calcium carbonate.
Getting all this into a working plant is quite another matter andwill take time to master and time to implement.
Could the humblesea urchin hold the key to carbon capture?
http://www.ncl.ac.uk/press.office/press.release/item/could-the-humble-sea-urchin-hold-the-key-to-carbon-capture#.URCzfiaxb-Y
The discovery that seaurchins use Nickel particles to harness carbon dioxide from the seacould be the key to capturing tonnes of CO2 from the atmosphere.
Experts at NewcastleUniversity, UK, have discovered that in the presence of a Nickelcatalyst, CO2 can be converted rapidly and cheaply into the harmless,solid mineral, calcium carbonate.
Thisdiscovery, which is published today in the academic journal CatalysisScience & Technology, has the potential to revolutionise the waywe capture and store carbon enabling us to significantly reduce CO2emissions – the key greenhouse gas responsible for climate change.
Dr LidijaÅ iller, a physicist and Reader in Nanoscale Technology at NewcastleUniversity, says the discovery was made completely by chance.
“We had setout to understand in detail the carbonic acid reaction – which iswhat happens when CO2 reacts with water – and needed a catalyst tospeed up the process,” she explains.
“At the sametime, I was looking at how organisms absorb CO2 into their skeletonsand in particular the sea urchin which converts the CO2 to calciumcarbonate.
“When weanalysed the surface of the urchin larvae we found a highconcentration of Nickel on their exoskeleton. Taking Nickelnanoparticles which have a large surface area, we added them to ourcarbonic acid test and the result was the complete removal of CO2.”
At the moment,pilot studies for Carbon Capture and Storage (CCS) systems proposethe removal of CO2 by pumping it into holes deep underground. However, this is a costly and difficult process and carries with it along term risk of the gas leaking back out - possibly many miles awayfrom the original downward source.
An alternativesolution is to convert the CO2 into calcium or magnesium carbonate.
“One way todo this is to use an enzyme called carbonic anhydrase,” explainsGaurav Bhaduri, lead author on the paper and a PhD student in theUniversity’s School of Chemical Engineering and Advanced Materials.
“However,the enzyme is inactive in acid conditions and since one of theproducts of the reaction is carbonic acid, this means the enzyme isonly effective for a very short time and also makes the process veryexpensive.
“The beautyof a Nickel catalyst is that it carries on working regardless of thepH and because of its magnetic properties it can be re-captured andre-used time and time again. It’s also very cheap – 1,000 timescheaper than the enzyme. And the by-product – the carbonate –is useful and not damaging to the environment.
“What ourdiscovery offers is a real opportunity for industries such as powerstations and chemical processing plants to capture all their wasteCO2 before it ever reaches the atmosphere and store it as a safe,stable and useful product.”
Each year,humans emit on average 33.4 billion metric tons of CO2 - around 45%of which remains in the atmosphere. Typically, a petrol-drivencar will produce a ton of CO2 every 4,000 miles.
Calciumcarbonate, or chalk, makes up around 4% of the Earth’s crust andacts as a carbon reservoir, estimated to be equivalent to 1.5 millionbillion metric tons of carbon dioxide.
It is the maincomponent of shells of marine organisms, snails, pearls, andeggshells and is a completely stable mineral, widely used in thebuilding industry to make cement and other materials and also inhospitals to make plaster casts.
The processdeveloped by the Newcastle team involves passing the waste gasdirectly from the chimney top, through a water column rich in Nickelnano-particles and recovering the solid calcium carbonate from thebottom.
Dr Å illeradds: “The capture and removal of CO2 from our atmosphere is one ofthe most pressing dilemmas of our time.
“Our processwould not work in every situation – it couldn’t be fitted to theback of a car, for example – but it is an effective, cheap solutionthat could be available world-wide to some of our most pollutingindustries and have a significant impact on the reduction ofatmospheric CO2.”
The team havepatented the process and are now looking for an investor to take itforward.published on: 5thFebruary 2013
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