Tag Archives: carbon capture

In Iceland, CO2 is sucked out of the air and turned into rock

A facility in Iceland is taking atmospheric carbon dioxide (CO2), the main culprit of climate change, and injecting it into volcanic rocks deep underground. While this is still early days and the volume of CO2 isn’t too great, this type of technology could be very important in the future.

The Orca plant. Image credits: Climeworks.

Even if we’d magically stop all our greenhouse gas emissions tomorrow, the inertia of our past emissions would still push the planet to warm a bit. If we continue “business as usual”, things will be way worse. So why don’t we just take greenhouse gases out of the air and store them somewhere safe where they can’t contribute to global warming?

The idea is not new, but of course, it’s easier said than done. Separating out the right gases, processing them, and storing them somewhere where they can’t escape back into the atmosphere are all big challenges — and doing them all together is even more demanding. But a company working in Iceland is not deterred.

Climeworks is a Swiss company specializing in carbon dioxide air capture technology. They’ve recently built a plant in Iceland called Orca that can capture 4000 tons of CO2 per year, making it the biggest climate-positive facility in the world.

Orca (the Icelandic word for energy) lies near the Hellisheiði Power Station — the third largest geothermal power plant in the world. It consists of eight containers stacked up two by two; fans in front of a collector draw ambient air, the air passes through a selective material that collects CO2, and the CO2-depleted air is then released at the back. It’s a bit like “mining” the sky for CO2 — simple in principle, though very difficult to implement.

What happens next is also not exactly simple. After the filter is full, it’s heated to around 100 degrees Celsius to clear the CO2 of any impurities, and then piped underground a distance of three kilometres (1.8 miles) to dome-shaped facilities in a moon-like landscape where it is dissolved in water and then injected under high pressure into basalt rock 800-2000 meters deep. The injection facility was developed by Carbfix which pioneered underground carbon storage.

The injection facility. Image credits: Carbfix.

The dissolved solution starts filling the cavities of the subsurface basalt and reacting with the rock, solidifying and turning into minerals in about two years.

To do this, you need the right geology, and Iceland offers just that. Much of Iceland is a basaltic field, where this dissolved gas can be safely injected. The only way the CO2 would be released into the air is in the case of a volcanic eruption, but the injection site was chosen in an area where the risk of an eruption is very low.

A core of basalt rock (black part) with the injected CO2 (white part). Image credits: Climeworks.

However, as exciting and promising as this technology is, it won’t save us from climate change on its own. While Orca can suck up to 4000 tons of CO2 per year, the yearly global emissions are around 33.4 billion tons of CO2 — so the plant can dispose of 0.00001% of our yearly emissions. Climeworks says this is mostly a trial and it will achieve megaton removal capacity in the second part of the decade, but even one megaton is still a very small percentage of our emissions. To make matters even more complicated, the process is costly and requires large amounts of energy. While the plant is run on renewable energy, this still makes scaling more difficult.

In fact, carbon capture is making such a small dent in our total emissions that critics have argued that it’s a costly distraction from the real policy measures needed to fight climate change. It’s true that only reducing our emissions can prevent catastrophic climate change, but “you have to learn to walk before you can run,” says Julie Gosalvez, in charge of marketing for Climeworks.

Carbon storage is just emerging as a technology. It won’t help us fix climate change yet, but it can be important down the line — provided we have the right conditions for it. The only way it can work is if the world implements a carbon tax, and extracting carbon from the air is incentivized. This makes economic sense, but for now, there’s no such carbon tax on the horizon.

World’s largest carbon capture plant opens up in Iceland

A massive facility that can suck carbon dioxide out of the air and deposit it underground has officially begun operating in Iceland. This could be a big step forward for the technology, which has been suggested by climate experts as necessary to reduce greenhouse gases in a way to meet the targets of the Paris Agreement. 

The Orca plant in Icelad. Image credit: Carbfix.

The plant is named Orca, after the Icelandic word “orka” which means energy. It was built jointly by the Swiss company Climeworks and the Icelandic company Carbfix, with a cost between $10 and $15 million. It will capture 4,000 tons of carbon dioxide sucked up from the air every year – which is equivalent to the greenhouse emissions from about 870 cars. That’s a drop in the bucket, but bear in mind this is still a pilot project, whose carbon absorption can be quickly scaled to meet growing demand.

It wasn’t randomly built in Iceland. The tiny island nation has the ideal underground geology to capture carbon and plenty of geothermal energy. Still, the costs are too high at the moment, at about $600 to $800 per metric ton of CO2. This is due to the energy requirements for the process and to the fact that it’s a fairly new piece of technology. The way all of it works, though, is intriguing.

Orca has four units, each made up of two metal boxes that are similar to the ones used in the shipping industry. Fans are built into the boxes, which capture CO2 out of the air through spongelike filters. These are blasted with heat, freeing the gas. Then the gas is mixed with water and pumped into underground caverns, where it turns into dark-gray stone. 

But there are other ways of getting rid of the CO2. Farmers can use it for their plants, energy companies can mix it with hydrogen to make fuel, and soda manufacturers can use it to fizz their drinks. That’s why selling the captured CO2 could also be a way to lower the costs of the plant and to rely less on the current government subsidies. 

“This is indeed an important step in the race to net-zero greenhouse gas emissions, which is necessary to manage the climate crisis,” Icelandic Prime Minister Katrin Jakobsdottir said at the opening ceremony. “This almost sounds like a science fiction story, but we do have other examples in our history of amazing advances in technology.”

Direct carbon capture

The technology used by Orca is known as direct carbon capture, one of the few ways to capture CO2 from the atmosphere. While scientists say it’s a necessary step in the fight against climate change, critics have argued that it’s still too expensive and that it could take decades to operate at scale. Still, the fact that Orca opened up is already a big first step.

At the moment, there are 15 direct carbon capture plants operating worldwide, mainly found in the US, Europe, and Canada, which cumulatively capture about 9,000 tons of CO2 per year, according to the International Energy Agency (IEA). A large-scale plant is currently being developed in the US that would have the capacity to pull one million tons per year of CO2 from the air. 

Governments and business leaders are more focused on replacing fossil fuels with renewable energy rather than on exploring carbon capture. While it’s true that renewables are getting cheaper energy day, there’s a big part of our emissions that come from other industrial activities that are very hard to decarbonize, such as cement factories.

This is where carbon capture can come in and make a difference. The Intergovernmental Panel on Climate Change (IPCC), a leading group of climate experts, has repeatedly mentioned the use of the technology as necessary to mitigate our emissions, as well as the IEA in its reports. More and more, researchers are considering it as a necessary technology ahead. 

A study by Imperial College London said last year that no more than 2,700 gigatons (Gt) of CO2 would have to be captured to meet the most aggressive climate targets. The researchers also argued that the current rate of growth in the installed capacity of CCS is not on track to meet those targets, but asked to maintain the research and commercial efforts in place. 

Scotland is building a massive plant capable of removing one million tons of CO2 from the air every year

The plant, Scotland is proposing will remove the same amount of CO2 as around 40 million trees. It would become operational by 2026 and the captured greenhouse gases would be stored permanently under the seabed off the Scottish coast.

A model of the plant. Image credit: Storeega.

If we want to avoid the brunt of climate change, we’d do best to keep temperature rise below 1.5ºC. But time is all but running out, as global temperatures have already increased 1.2ºC above their historical level. So in addition to ways of reducing emissions, researchers are also looking at ways to remove large amounts of carbon emissions from the atmosphere. Carbon capture and storage (CCS) is one such way. 

CCS involves the extraction of emissions from power plants and factories, condensing them and then pumping the resulting carbon dioxide into underground stores. The UK is well placed to use CCS as it already has the place to store carbon dioxide — in its many depleted North Sea oil fields where this sequestrated carbon dioxide could be stored.

As part of his commitment to fight climate change, UK Prime Minister Boris Johnson has pledged $1.4 billion of public funds to help develop four major CCS schemes in Britain by 2030 as part of his plan for a “green industrial revolution”. The aim, Johnson said, is to make the UK a world leader in the technology, creating thousands of jobs. Scotland in particular wants to make the most of this funding, by building a new massive carbon storage plant.

A massive new plant

The new project in Scotland will be carried out between the UK firm Storeega and the Canadian company Carbon Engineering. It’s at a very early stage of development, with a long way to go — but if all goes ahead, it will be one of the biggest CCS plants in the world. A site for the plant won’t be selected until next year. 

“Even if all the other measures that we’re taking to avoid emissions, electric cars, renewable energy, those types of things, even if those succeed, you still need carbon removal,” Steve Oldham, CEO of Carbon Engineering, told the BBC. “A typical facility is about a million tonnes of CO2 removal per year. That’s the equivalent of 40 million trees.”

The CCS system that will be deployed involves a fan to suck in air, which is exposed to a liquid mixture that binds the carbon dioxide. The liquid is then turned into calcium carbonate pellets. When these are treated at a temperature of about 900ºC, the pellets decompose into a CO2 stream and calcium oxide. That stream of pure CO2 is cleaned up to remove water impurities. At that point, it can be pumped underground and buried permanently or sold for commercial use. 

Scotland has significant advantages for this type of technology, as it has an abundant flow of renewable energy and a skilled workforce from the oil industry. But the technology has its fair number of critics. Researchers and campaigners have expressed concern that if CCS capture becomes economically viable, then governments might stop cutting emissions as they will rely on capturing CO2 — instead of the far more efficient strategy of not producing it in the first place.

However, supporters argue this won’t be the case, claiming the technology will be useful for sectors that have difficulties reducing their emissions, such as aviation. 

“It’s a much more sensible strategy to treat these technologies as a really nice addition. We should work hard on them and make sure that they can become cost competitive, and economic in the 2020s,” Ajay Gambhir, a senior research fellow at the Grantham Institute for Climate Change and the Environment, told the BBC. “But at the same time, we need to just make sure we reduce emissions as fast as possible as far as possible.”

Several CCS development programes have been launched over the past 20 years. According to the Global CCS Institute’s 2020 report, at that time there were 65 large-scale CCS facilities globally. 26 of these were in operation, three are in construction, 21 are in early development, 13 are in advanced development and two have suspended operations. 

Carbon capture could be worse than initially thought, study shows

As the climate crisis worsens, the use of carbon capture has been suggested as an alternative to reduce emissions levels in the atmosphere. But capturing carbon from the air or preventing it from getting there could actually cause more harm than good, according to a new study.

Credit: Wikipedia Commons

All climate scenarios for the future now contemplate the use of carbon capture, trapping emissions and storing them away from the atmosphere. But, for researcher Mark Jacobson, technology reduces only a small fraction of carbon emissions and usually increases air pollution.

“Even if you have 100 percent capture from the capture equipment, it is still worse, from a social cost perspective, than replacing a coal or gas plant with a wind farm because carbon capture never reduces air pollution and always has a capture equipment cost,” Jacobson said.

The researcher looked at public data from a coal with carbon capture electric power plant and a plant that removes carbon from the air directly. In both cases, the electricity needed to run the carbon capture came from natural gas. He calculated the net CO2 reduction and total cost of the carbon capture process in each case.

Estimates of carbon capture say it can remediate 85-90 percent of carbon emissions. Once he calculated the emissions associated with the plants, the scientist converted them to the equivalent amount of carbon dioxide in order to compare the data with the standard estimate. In both cases, the equipment captured the equivalent of only 10-11% of the emissions they produced, averaged over 20 years.

Jacobson also looked at the social cost of carbon capture, including air pollution, potential health problems, economic costs and overall contributions to climate change. He concluded that those are always similar to or higher than operating a fossil fuel plant without carbon capture and higher than not capturing carbon from the air at all.

Even when the capture equipment is powered by renewable electricity, the study concluded that it is always better to use renewable electricity instead to replace coal or natural gas electricity or to do nothing, from a social cost perspective. It then argued the best solution is to instead focus on renewable options.

The research was based on data from two real carbon capture plants, which both run on natural gas. The first is a coal plant with carbon capture equipment. The second plant is not attached to any energy-producing counterpart. Instead, it pulls existing carbon dioxide from the air using a chemical process.

“Not only does carbon capture hardly work at existing plants, but there’s no way it can actually improve to be better than replacing coal or gas with wind or solar directly,” said Jacobson. “The latter will always be better, no matter what, in terms of the social cost. You can’t just ignore health costs or climate costs.”

Experts propose that carbon capture could be useful in the future to lower atmospheric carbon levels. Even assuming these technologies run on renewables, Jacobson maintains that the smarter investment is in options that are currently disconnected from the fossil fuel industry, such as reforestation.

The study appeared in the journal Energy and Environmental Science.

“Algae forestry” could take CO2 straight out of the air and put it on your plate

Through a mixture of algae, eucalyptus, carbon storage and bioenergy, researchers believe they have found the recipe to simultaneously provide food in many parts of the world while taking out CO2 from the atmosphere.

As the world struggles to keep global warming at manageable levels, scientists are exploring several avenues to reduce emissions. Researchers from Cornell University, Duke University, and the University of Hawaii at Hilo have an idea that could prove extremely effective: they devised a system that can act as a carbon dioxide sink while also generating food and electricity.

They integrated algae production with carbon capture, in a system they call ABECCS (algae bioenergy carbon capture and storage). Researchers have already set up a 7,000-acre ABECCS facility that can yield as much protein as soybeans produced on the same land footprint, while simultaneously generating 17 million kilowatt hours of electricity and sequestering 30,000 tons of carbon dioxide per year. A portion of the captured COis used for growing algae and the remainder is sequestered. Biomass combustion supplies CO2, heat, and electricity, thus increasing the range of sites suitable for algae cultivation.

“Algae may be the key to unlocking an important negative-emissions technology to combat climate change,” said Charles Greene, Cornell professor of Earth and Atmospheric Sciences and a co-author of new research published in Earth’s Future, by the American Geophysical Union.

“Combining two technologies — bio-energy with carbon capture and storage, and microalgae production — may seem like an odd couple, but it could provide enough scientific synergy to help solve world hunger and at the same time reduce the level of greenhouse gases that are changing our climate system,” Greene said.

Often times, when an idea sounds too good to be true, it is. In this case, the entire project hinges on the economic viability of the algae. Researchers describe two scenarios in which financial viability is achieved:

  • when algal biomass can be sold for $1,400/t (as fishmeal replacement), with a $68/t carbon credit; and
  • algal biomass sold for $600/t (soymeal replacement) with a $278/t carbon credit.

Clearly, the price of algal biomass is essential, but an economy that supports carbon credits is also required.

There’s another issue with this type of project: In the ABECCS system, soy cropland is replaced by eucalyptus forests used for carbon storage that provides marine algae with CO2, heat, and electricity. While this can work extremely well on a small scale, on a large scale, the arable land and freshwater requirements for ABECCS could be unviable and cause competition with food production.

ABECCS won’t solve all our climate change woes, but it could be a significant puzzle piece.

Journal Reference: Colin M. Beal, Ian Archibald, Mark E. Huntley, Charles H. Greene, Zackary I. Johnson. Integrating Algae with Bioenergy Carbon Capture and Storage (ABECCS) Increases Sustainability. Earth’s Future, 2018; DOI: 10.1002/2017EF000704

The Semail (or Samail) ophiolite landscape as seen in a 2012 NASA satellite image. Credit: NASA.

Could Oman’s mountains hold the key to reversing climate change?

Deep inside the jagged red mountains of Oman, visitors with a trained eye might be shocked by an amazing sight: the world’s only exposed sections of the Earth’s mantle. Scientists are now sampling cores from this region to find out how a spontaneous process turned CO2 into limestone and marble millions of years ago. The answers they might unravel could one day offer a cheap and efficient solution for removing CO2 from the atmosphere and oceans.

The Semail (or Samail) ophiolite landscape as seen in a 2012 NASA satellite image. Credit: NASA.

The Semail (or Samail) ophiolite landscape as seen in a 2012 NASA satellite image. Credit: NASA.

Capturing carbon

The average American needs around 980 trees to offset their carbon footprint. Massive reforestation, especially in those hard struck parts of the world, must be a top priority in any policy meant to tackle climate change. But the truth is after you add the numbers, trees aren’t enough. We’re simply releasing more carbon from beneath the ground in the form of fossil fuels than any large forest can absorb. This is why many scientists are so interested in carbon capture and storage (CCS) technologies.

One of the most promising CCS projects I’ve come across is the Hellisheidi geothermal plant in Iceland. Here, carbon dioxide is dissolved in water and injected into the ground where it interacts with the surrounding rock and becomes mineralized. The whole process is 95 to 98 percent efficient and CO2 can basically turn into a rock in just two years.

Elsewhere, in China, the Sinopec fertilizer plant filters carbon and reuses it as fuel. According to the International Energy Agency, overall some 27 million tons of carbon are currently captured and stored across the world by 16 projects. An impressive start but in the grand scheme of things, that’s barely a dent (0.1%) in the 40 billion tons or so that human activity emits yearly.

“Any one technique is not guaranteed to succeed,” said Stuart Haszeldine, a geology professor at the University of Edinburgh who serves on a U.N. climate body studying how to reduce atmospheric carbon, for the Associated Press. “If we’re interested as a species, we’ve got to try a lot harder and do a lot more and a lot of different actions,” he said.

Naked Earth and its submerged mountains

One unique pathway for mitigating carbon in the atmosphere might be hiding in plain sights, in the rock formations of the al-Hajjar Mountains of Oman. The rugged mountains stand at their highest at 2,500 meters (8,200 feet) above sea level. Millions of years ago, some parts of these mountains were below the sea level. Many rocks used to lie in Earth’s interior, at the boundary between crust and mantle, but when the ancient Tethys Ocean narrowed and closed, the squeezing force thrust the ancient sea floor upward. This sort of landform is known to geologists as ophiolite, a term that describes oceanic crust that now sits at the land surface.

“You can walk down these beautiful canyons and basically descend 20 kilometers (12 miles) into the earth’s interior,” said in a statement Peter Kelemen, a geochemist at Columbia University’s Lamont-Doherty Earth Observatory, who has been exploring Oman’s hills for nearly three decades.

There are various rocks that comprise the ophiolite sequence. Along the boundary with the base of the crust, you can find chromite which the sultanate mines. Elsewhere, some layers of rocks (the first in the crust, rather than the mantle) are composed of gabbro. But what interests climate scientists is the peridotite, a rock that was once part of Earth’s mantle and reacts with the carbon in air and water to form marble and limestone.

It’s believed a billion tons of CO2 is trapped in the peridotites of al-Hajjar Mountains. When rain pulls carbon from the exposed mantle,  stalactites and stalagmites form in the mountain caves.

In order to understand how all of this process works, Kelemen and 40 other scientists have formed the Oman Drilling Project. So far, $3.5 million in funding has been pledged by organizations around the world, among which NASA.

So far, the team has dug up dozens of core samples from four different sites in Oman’s mantle-exposed mountains. Some 13 tons of core samples will be shipped to the Chikyu, a research vessel off the coast of Japan where geologists will work round-the-clock shifts to better understand the chemical process that traps the carbon in rock. They’ll also be interested in finding ways to speed up the process given all that carbon has accumulated over 90 million years and time is not really on our side. In only 150 years, average CO2 levels in the atmosphere have soared from 280 to 405 parts per million.

“Just like in Oman’s mountains, the submerged rock would chemically absorb carbon from the water. The water could then be cycled back to the surface to absorb more carbon dioxide from the atmosphere. However, that would be following years of rigorous testing, but hopefully this project, and this discovery retains support,” Kelemen told the Oman Times.

Late 2015, 196 nations signed and later ratified the Paris Agreement — an international pact where each signatory pledges to cap or reduce its carbon emissions such that collectively we might steer away from any pathway that leads to more than 2 degrees C of warming. The elections in the United States have side tracked a bit this landmarked agreement, though officially all the other signatories besides the United States have vowed to stay steadfast and deliver on their pledges.

According to some estimates, however, the planet is already locked into 1.5 degrees C of warming. Renewable energy and energy efficiency measures, coupled with the scrapping of coal, oil, and gas, are paramount if we want to avoid catastrophic runaway global warming. But seeing how CO2 can stay in the atmosphere for up to two centuries, these measures have to be joined by CCS. With every passing day, CCS becomes more and more important. Hopefully, al-Hajjar’s secrets might help save us and the countless other species we share this planet with.

 

Scientists turn CO2 into rock in Iceland

An international team of scientists documented a potentially viable way to remove anthropogenic (caused or influenced by humans) carbon emissions from the atmosphere: by turning into rock.

Air photograph of Reykjavik Energy’s Hellisheidi geothermal power plant. Credit: Árni Sæberg

No matter how much you talk and spin it around, the problem with global warming bounds down to one thing: we’re outputting too much greenhouse gas into the atmosphere, especially carbon dioxide (CO2). But what if we could somehow cheat, and trap that CO2 and lock it away somewhere where it wouldn’t do any damage? That’s what many teams believe is a key point of mitigating climate change, and that’s exactly what scientists working in Iceland have done.

The CO2 interacts with the surrounding rock, forming environmentally benign minerals. The entire process is quite fast, and it could perhaps be scaled.

Carbon Capture and Storage (CCS) is a field of science where CO2 is extracted from the atmosphere and stored underground. Geologists have mostly focused on existing voids, such as former oil fields, but that’s tricky because the fields are susceptible to leakage. So instead, they’re now turning to mineralizations – turning CO2 into minerals. Until now, this process was thought of as unpractical because it takes too long to solidify the CO2, but researchers from Columbia University, University of Iceland, University of Toulouse and Reykjavik Energy have found a way to make it work in two years.

Lead author Dr Juerg Matter, Associate Professor in Geoengineering at the University of Southampton, says:

“Our results show that between 95 and 98 per cent of the injected CO2 was mineralised over the period of less than two years, which is amazingly fast.”

They key is basalt – a volcanic rock which Iceland has an abundance of. The whole Iceland is made up of basalt (90%), and the rock is also rich in calcium, magnesium in iron – key elements for carbon mineralization. The process is straightforward: CO2 is dissolved in water and carried down the well. When it comes into contact with the rocks, it reacts and starts forming carbonate minerals. After two years, the carbon is completely trapped.

“Carbonate minerals do not leak out of the ground, thus our newly developed method results in permanent and environmentally friendly storage of CO2 emissions,” says Dr Matter, who is also a member of the University’s Southampton Marine and Maritime Institute and Adjunct Senior Scientist at Lamont-Doherty Earth Observatory Columbia University. “On the other hand, basalt is one of the most common rock type on Earth, potentially providing one of the largest CO2 storage capacity.”

Already, the project is storing 10,000 tonnes of CO2 a year and many other areas are highly rich in basaltic rocks, which means the same could be applied elsewhere.

“In the future, we could think of using this for power plants in places where there’s a lot of basalt and there are many such places,” said Martin Stute, at Columbia University in the US and part of the research team.

The big resource being used here is water – the process requires a lot of water, but thankfully, seawater can also be successfully used. Basalts are often found in proximity of oceans, so the problem could be solved with relative ease.

“The overall scale of our study was relatively small. So, the obvious next step for CarbFix is to upscale CO2 storage in basalt. This is currently happening at Reykjavik Energy’s Hellisheidi geothermal power plant, where up to 5,000 tonnes of CO2 per year are captured and stored in a basaltic reservoir.”

The project is part of research funded by the European Union. The investigation is part of the CarbFix project, a European Commission and U.S. Department of Energy funded programme to develop ways to store anthropogenic CO2 in basaltic rocks through field, laboratory and modelling studies.

 

Copper clusters could revolutionize CO2 capture and turn it into fuel to boot

The chemical reactions used to make methanol from carbon dioxide rely on a catalyst to speed up the conversion, and scientists identified a new material that could fill this role. With its unique structure, this catalyst can capture and convert carbon dioxide in a way that ultimately saves energy.

The copper tetramer catalyst created by researchers at Argonne National Laboratory may help capture and convert carbon dioxide in a way that ultimately saves energy.
Credit: Image courtesy Larry Curtiss, Argonne National Laboratory

We have covered carbon capture before, so you should be familiar with the underlying idea – capture CO2 and convert it into a easily storable, inert substance. Recent advances gave us new ways to turn this green house gas into useful substances, such as building materials, or use it to produce light or even fuel. One of the products that can be obtained this way, and then be used as fuel is methanol, a pretty simple carbon, oxygen and hydrogen molecule that my chemistry teacher loved to quiz me about so i hate.

Producing methanol this way first requires an efficient method of fishing carbon compounds out of the atmosphere, a process which up to now involved highly-pressurizing gasses over a chemical capture compound made up of copper, aluminium oxide and zinc oxide. A team of researchers working out of the U.S. Department of Energy’s (DOE) Argonne National Laboratory has developed a new compound that they hope will revolutionize the process, as with its unique structure, this catalyst can capture and convert carbon dioxide in a way that ultimately saves energy.

Methanol -also known as wood alcohol- chemical structure.
Image via biologycorner

The compound is called copper tetramer. It’s made up of small clusters of four copper atoms each, spread on a thin film of aluminium oxide. These catalysts work by binding carbon dioxide molecules, and orienting them in a way that facilitates chemical reactions. The structure of the copper tetramer is more efficient as most of it’s binding sites are open, so that it can attach more strongly to CO2 and accelerate the conversion. As it stands, a number of the binding sites in the now-used capture compound are occupied merely in holding the substance together, which limits how many atoms can catch and hold carbon dioxide.

“With our catalyst, there is no inside,” said Stefan Vajda, senior chemist at Argonne and the Institute for Molecular Engineering and co-author on the paper. “All four copper atoms are participating because with only a few of them in the cluster, they are all exposed and able to bind.”

This is why the current method calls for high-pressure environments in which the capture to take place, so that stronger bonds form between the CO2 molecules and the bonding compound.  But compressing gas into a high-pressure mixture takes a lot of energy. The benefit of enhanced binding is that the new catalyst requires lower pressure and less energy to produce the same amount of methanol.

Carbon dioxide emissions are an ongoing environmental problem, and according to the authors, it’s important that research identifies optimal ways to deal with the waste.

“We’re interested in finding new catalytic reactions that will be more efficient than the current catalysts, especially in terms of saving energy,” said Larry Curtiss, an Argonne Distinguished Fellow who co-authored this paper.

Copper tetramers could allow us to capture and convert carbon dioxide on a larger scale — reducing an environmental threat and creating a useful product like methanol that can be transported and burned for fuel. Of course the catalyst still has a long journey ahead from the lab to industry.

Some of the kinks that still have to be ironed out are the compound’s instability and finding an efficient way to manufacture mass quantities of the substance. There is a chance that the tetramers may decompose in an industrial setting, so ensuring long-term durability is a critical step for future research, Curtiss said. And while only nanograms of the material were required for lab studies, a much higher quantity would be needed for industrial purposes.

Meanwhile, the researchers are interested in searching for other catalysts that might even outperform their copper tetramer.

These catalysts can be varied in size, composition and support material, which results in a list of more than 2,000 potential combinations, Vajda said.

But the scientists don’t have to run thousands of different experiments, said Peter Zapol, an Argonne physicist and co-author of this paper. Instead, they will use advanced calculations to make predictions, and then test the catalysts that seem most promising.

“We haven’t yet found a catalyst better than the copper tetramer, but we hope to,” Vajda said. “With global warming becoming a bigger burden, it’s pressing that we keep trying to turn carbon dioxide emissions back into something useful.”

For this research, the team used the Center for Nanoscale Materials as well as beamline 12-ID-C of the Advanced Photon Source, both DOE Office of Science User Facilities.

Curtiss said the Advanced Photon Source allowed the scientists to observe ultralow loadings of their small clusters, down to a few nanograms, which was a critical piece of this investigation.

Fjords are good at fighting global warming, study finds

While fjords are admired worldwide for their unique beauty, a new study has found that these natural ecosystems also act as carbon sinks, playing an important role in regulating our planet’s climate.

Fjords are effective at storing carbon, helping regulate global climate. Image via Wiki Commons.

Fjords (alternate spelling: Fiords) are geological features emerging as long, narrow inlets with steep cliffs. Fjords are created by glacial erosion, with most of them being located in Norway, Alaska, Greenland and Chile, but they’re much more than a popular touristic attraction. A study published in Nature Geoscience found that fjords alone are capable of storing huge quantities of organic carbon washed up by rivers; although they make up for less than 0.1 percent of the oceanic surface, fjords are responsible for storing no less than 11 percent of the total mass of organic carbon buried each year in marine sediments.

“Despite being small, fiords are mighty,” scientist Richard Keil reacted after he saw the study published in Natural Geoscience. The scientific community is pleased to see that the effectiveness of the fjords at storing carbon is finally being assessed correctly, after decades during which they have been completely ignored.

What makes them so effective at storing carbon is the fact that they are deep, and their generally calm waters are poor in oxygen – which enables carbon to sink down to the bottom without being touched by bacteria, and without being decomposed.

“Therefore, even though they account for only 0.1% of the surface area of oceans globally, fjords act as hotspots for organic carbon burial,” Dr Candida Savage of New Zealand’s University of Otago says.

However, while on a human scale, fjords do act as a carbon sink, on a geological scale, they are just a way of ensuring carbon cycling. We are now in an interglacial period, but as the glaciers eventually start advancing, the stored carbon will be pushed out.

“In essence, fjords appear to act as a major temporary storage site for organic carbon in between glacial periods. This finding has important implications for improving our understanding of global carbon cycling and climate change,” she says.

The study was based on analysis on 573 surface sediment samples and 124 sediment cores from fjords around the world.

Journal Reference: Richard W. Smith, Thomas S. Bianchi, Mead Allison, Candida Savage & Valier Galy. High rates of organic carbon burial in fjord sediments globally. Nature Geoscience (2015) doi:10.1038/ngeo2421

geological hacks

Climate change reversal hacks shunned in report. “Wake up and cut emission!”

Mitigating climate change is on the agenda of every world government, but somehow little is done to curb global warming. Echoing a quick-fix approach to life so predominantly engraved in modern culture, some are considering sweeping climate change under the proverbial rug. These so called geo-engineering methods aim to fix climate change by altering the environment, but those ideas that are actually practical today only mask the effects and do nothing to treat the symptoms, a new report signed by 16 top scientists reads. The authors used this opportunity to make an appeal for reducing global emissions, else we might be forced to actually engineer the planet with unforeseeable consequences.

Geo hacks not the way to go

geological hacks

Image: Sam Doust

A few years back, one British panel asked for immediate financial support into researching climate-altering interventions. The newly released twin report,  Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration and Climate Intervention: Reflecting Sunlight to Cool the Earth, is much more skeptical and cautions on how the world should approach geo-engineering solutions, which can be extremely dangerous and might end up doing more harm than good. What’s important though is that these matters are being discussed and analyzed now, when there is still time to act. The alternative is to act in the heat of the moment, once climate change becomes too “hot” to ignore. As such, agencies backed by both government and private ventures, like Bill Gates’ foundation, are currently research the viability of these methods.  Still, relying on a planetary hack – instead of cutting carbon dioxide emissions – is “irresponsible and irrational”, the report said.

“That scientists are even considering technological interventions should be a wake-up call that we need to do more now to reduce emissions, which is the most effective, least risky way to combat climate change,” Marcia McNutt, the committee chair and former director of the US Geological Survey, said.

The report discusses at large some of these planetary hacks. The two most popular methods are carbon capture and sequestration (CCS), which basically involves siphoning CO2 from the atmosphere and storing it deep underground similarly to how some pilot coal-fired power plants are already doing, and albedo modification. The albedo is a scientific term that refers to how much sunlight is being reflected back in space. By injecting albedo altering chemicals in the upper atmosphere, like sulphur dioxide, more energy will be reflected and thus temperatures will be lower.

Albedo modification doesn’t lower CO2 concentration, however. The greenhouse gas will still remain in the atmosphere for centuries to come before it breaks down and, worse off, the method does nothing to curb ocean acidification. Up to 90% of all CO2 spewed into the atmosphere is absorbed by the planet’s oceans, causing a drop in pH severely affecting coral and plankton life, with spiraling consequences for the world’s ecosystems.

1. A million tons of sulfur dioxide would be needed to begin the cooling process. Luckily SO2, a byproduct of coal-burning power plants, is a common industrial chemical. 2. Inject it into the stratosphere. Load the sulfur dioxide into aircraft — converted 747s, military fighters, or even large balloons — and carry it up to the stratosphere. This will cost about $1 billion a year. 3. Wait for the chemical reaction. In a series of reactions, sulfur dioxide combines with other molecules in the atmosphere, ultimately forming sulfuric acid. This H2SO4 binds to water to form aerosol droplets that absorb and reflect back into space 1 to 3 percent of the sun's rays. (The particles also contribute to the depletion of the ozone layer, but scientists are researching alternate chemicals.) 4. Let the planet cool. Credit: Wired

1. A million tons of sulfur dioxide would be needed to begin the cooling process. Luckily SO2, a byproduct of coal-burning power plants, is a common industrial chemical. 2. Inject it into the stratosphere. Load the sulfur dioxide into aircraft — converted 747s, military fighters, or even large balloons — and carry it up to the stratosphere. This will cost about $1 billion a year. 3. Wait for the chemical reaction. In a series of reactions, sulfur dioxide combines with other molecules in the atmosphere, ultimately forming sulfuric acid. This H2SO4 binds to water to form aerosol droplets that absorb and reflect back into space 1 to 3 percent of the sun’s rays. (The particles also contribute to the depletion of the ozone layer, but scientists are researching alternate chemicals.) 4. Let the planet cool. Credit: Wired

Albedo intervention on a global scale, which seems to be viable according to computer models and real-life experience from volcanic eruptions, can also be dangerous on multiple levels. First, we might actually cool the planet more than we’d have to, secondly it’s unlikely that we can inject the sulfur compounds in a customized, distributed manner. Currents and wind gusts are too unpredictable for this to happen, so what might happen is some places will have a climate to their liking, but an African or Asian country might feel threatened because their rain patterns are now amok. Who should be in charge of spraying albedo modifying chemicals? How can smaller governments challenge a measure that affects the whole world? Conflicts and violence might arise. Overall, as you might have already guessed, the authors dismissed albedo intervention as absolutely nonviable.

“It’s hard to unthrow that switch once you embark on an albedo modification approach. If you walk back from it, you stop masking the effects of climate change and you unleash the accumulated effects rather abruptly,” Waleed Abdalati, a former Nasa chief scientist who was on the panel, said for The Guardian.

“The message is that reducing carbon dioxide emissions is by far the preferable way of addressing the problem,” said Raymond Pierrehumbert, a University of Chicago climate scientist, who served on the committee writing the report. “Dimming the sun by increasing the earth’s reflectivity shouldn’t be viewed as a cheap substitute for reducing carbon dioxide emissions. It is a very poor and distant third, fourth, or even fifth choice. |It is way down on the list of things you want to do.”

CO2 capture on the other hand is benign and is actually the way to go. Unfortunately, it costs so much to deploy at a scale where it might actually mitigate global warming that it’s completely unpractical at this point.

“I think there is a good case that eventually this might have to be part of the arsenal of weapons we use against climate change,” said Michael Oppenheimer, a climate scientist at Princeton University, who was not involved with the report.

Even so, compared to the albedo intervention, carbon sequestration is far ahead. The only problem with carbon sequestration is how much it costs, whereas the problem with albedo intervention is what might happen – we don’t know for sure!

“My view of albedo modification is that it is like taking pain killers when you need surgery for cancer,” said Pierrehumbert. “It’s ignoring the problem. The problem is still growing though and it is going to come back and get you.”

Carbon capture and storage (CCS) technology captures carbon emissions and stores them. In theory, this means carbon that would otherwise be emitted into the atmosphere can be locked up somewhere else - without the climate-altering effects. Image: Scottish Carbon Capture & Storage

Washing soda could be used to capture CO2 fired by power plants

Lawrence Livermore scientists have devised tiny capsules made up of a highly permeable polymer shell and a sodium carbonate solution that actively reacts with and absorbs carbon dioxide (CO2). Sodium carbonate is typically known as the main ingredient in washing soda, a common household item. The capsules are a lot cheaper and more environmentally friendly than other chemical carbon capture methods, according to the researchers.

Carbon capture and storage (CCS) technology captures carbon emissions and stores them. In theory, this means carbon that would otherwise be emitted into the atmosphere can be locked up somewhere else - without the climate-altering effects. Image: Scottish Carbon Capture & Storage

Carbon capture and storage (CCS) technology captures carbon emissions and stores them. In theory, this means carbon that would otherwise be emitted into the atmosphere can be locked up somewhere else – without the climate-altering effects. Image: Scottish Carbon Capture & Storage

While renewable energy is catching up, there are still a great deal of coal or natural gas fired power plants operating throughout the world, with many more opening their gates. Instead of going against the wave, scientists are trying to make the best of it and develop carbon capture methods that diminish the levels of greenhouse gases or toxic chemicals that are released in the flue gases.

[MUST READ] Carbon capture of the future turns CO2 into construction material

Microcapsules containing sodium carbonate solution are suspended on a mesh during carbon dioxide absorption testing. The mesh allows many capsules to be tested at one time while keeping them separated, exposing more of their surface area. Photo by John Vericella/LLNL

Microcapsules containing sodium carbonate solution are suspended on a mesh during carbon dioxide absorption testing. The mesh allows many capsules to be tested at one time while keeping them separated, exposing more of their surface area. Photo by John Vericella/LLNL

In the past decade or so, the industry has become heavily reliant on monoethanol amine (MEA) to capture carbon dioxide before it exits smokestacks. MEA, however, is extremely caustic forcing plants to employ high quality and expensive stainless steel throughout their pipelines where MEA crystals come into contact. Carbonates, on the other hand, are benign and require no additional fitting. This is mainly why the Lawrence Livermore scientists decided to work with sodium carbonate or washing soda, but what really made their work ingenious was the decision to encapsulate the carbon capturing solution.

Microcapsules have become increasingly popular in medicine, agriculture or even cosmetics, but this is the first time they’ve been used for carbon capture. Being spherical, the capsules offer a much greater active surface area, absorbing more CO2 than other solvents.  Putting the carbonate solution inside of the capsules also allows it to be used for CO2 capture without making direct contact with the surface of equipment in the power plant, as well as being able to move it between absorption and release towers easily, even when it absorbs so much CO2 that it solidifies, according to Roger Aines, one of the Lawrence Livermore team members.

Unlike more caustic solvents used in capturing CO2, the microcapsules only react with the gas of interest (in this case CO2).

“Encapsulation allows you to combine the advantages of solid capture media and liquid capture media in the same platform,” says Jennifer Lewis of Harvard School of Engineering and Applied Sciences, and key author of a paper appearing in the Feb. 5 edition of the journal, Nature Communications.

Washing soda is mined locally, instead of being manufacturing in plants using energy intensive, complex chemical process such as the case with MEA. More importantly, it’s easily recyclable and can be used time and time again.

“It can be reused forever, while amines break down in a period of months to years,” Aines says.

“We think the microcapsule technology provides a new way to make carbon capture efficient with fewer environmental issues,” he says. “Capturing the world’s carbon emissions is a huge task. We need technology that can be applied to many kinds of carbon dioxide sources with the public’s full confidence in its safety and sustainability.”

carbon capture tech

Carbon capture of the future might turn CO2 into construction materials

We all know that CO2 dumped in the atmosphere (consequences in the ocean, where the most carbon winds up actually are even dire  – i.e. ocean acidification) causes global warming through what’s commonly referred to as the greenhouse gas effect. Governments and various environmental panels have through out the years issued various policies meant on curbing emissions. Ironically, however, greenhouse gas emissions have only gone up, as year after year there seems to be a new record in how much CO2 gets released into the atmosphere, mainly due to developing countries catching up and becoming industrialized. Only recently, the world passed a frightening threshold after atmospheric CO2 levels reached 400ppm (parts per million) for the first time in 3 million years.

The reason I’m presenting these facts isn’t to inflict panic. Indeed, these are depressing data, however it’s important to build context especially when covering cutting edge research conducted by scientists working effortlessly to battle atmospheric CO2 dumping. One of the most creative solution is the development of carbon trapping technology, and exciting as the tech may be it still bears a grand challenge: what to do with the stored carbon. While more efficient plants and filters significantly cut down emissions, you still windup with excess carbon – sure it’s not in gaseous form as a CO2 compound, so it doesn’t contribute to the greenhouse gas effect, but you still need to get rid of it.

carbon capture tech

(c) carboncapture.us

Some byproducts get pumped into the ground directly, where it seeps though cracks of rock layers deep below the surface, a process that we already know causes huge chemical changes in the rock. Other methods involve dumping the stored carbon by pumping it into the ocean, where pressures below a certain depth will cause it to form a thick slurry that falls to coat the ocean floor – in theory, right at the bottom, it’s harmless. The method is promising when you need to dump a few tons of carbon, but at the massive industrial scale you need a system capable of disposing millions of tones of carbon – hint: it needs to be cheap; dirt cheap!

Researchers at University of Newcastle have come up with a new solution that not only elegantly solves this problem, but offers a practical use. What if instead of dumping the captured carbon you turn it into something useful? This is exactly the reasoning behind the Newcastle researchers project, recently awarded a $9 million grant, inspired by nature, namely the sequestration of CO2 as rocks of neutral carbonate in the Earth itself.

Using CO2 to construct the buildings of the future

Reacting gaseous CO2 with low grade minerals such as magnesium and calcium silicate produces limestone. The scientists’ idea is to exploit the process by combining their captured carbon with cheap minerals and voila! You’ve got some limestone-like material right at your disposal that you can fashion into bricks for construction purposes. You could use it for anything from buildings to paving. Limestone’s pretty resilient and strong, too. Actually, it has been used in everything from the Egyptian Pyramids to the British Parliament buildings.

A multidisciplinary research team, including Professors Bodgan Dlugogorski and Eric Kennedy from the University’s Priority Research Centre for Energy and Orica Senior Research Associate Dr Geoff Brent, have demonstrated the technology in small scale laboratory settings and led the funding bids.

“The key difference between geosequestration and ocean storage and our mineral carbonation model is we permanently transform CO2 into a usable product, not simply store it underground,” Professor Dlugogorski said.

Brilliant, but how come anyone didn’t think of this before? They have, but the problem has always been that the process is highly energy intensive. This means its expensive since you need to produce a lot of energy to funnel the process, then producing this energy typically implies burning fossil fuels, which releases carbon. You can understand how unreasonable the idea becomes. The breakthrough though is that the Newcastle researchers have devised a way of dramatically lowering the energy threshold. This same year, Newcastle  made the production of calcium carbonates “a thousand times cheaper” through the use of nickel nanoparticles. A similar process is employed for the “carbon limestone”.

“The Earth’s natural mineral carbonation system is very slow,” Professor Kennedy said. “Our challenge is to speed up that process to prevent CO2 emissions accumulating in the air in a cost-effective way.”

It might take a while before this process might catch on, however. For now, Newcastle plans on using its grant to built a mineral carbonation research pilot plant, expected to open in 2017. There the researchers can extend the findings in the lab to an environment similar to that found in the industry. If they can manage to produce mineral carbonation at a price that’s under current construction materials then they’ve hit the jackpot!

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