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A recent piece in the Proceedings of the National Academy of Sciences discusses geoengineering as a way to manipulate Earth’s climate in order to counteract global warming from greenhouse gas emissions.

Using a method described as “enhanced weathering,” researchers claim that piles of chalk could be used to stabilize the climate. The chalk piles could, in theory, remove as much CO₂ from the atmosphere as desired — although the practical challenges are enormous, said Tim Kruger of Oxford Geoengineering, a networking organization in the UK, speaking at a conference at the Royal Society in London earlier this week.

According to Kruger, adding calcium oxide (also known as quicklime and made from chalk) to the oceans would result in calcium hydroxide, which is strongly alkaline. This absorbs CO₂ dissolved in seawater, causing the ocean to suck replacement CO₂ out of the air.

“[This method has] the potential to draw down carbon dioxide without limit,” Kruger says, because the raw materials necessary are readily available.

Differences in global temperature, atmospheric CO2, and mean surface ocean pH induced by enhanced silicate weathering for A.D. 2010–2100.

Dieter Wolf-Gladrow of the Alfred Wegener Institute for Polar and Marine Research in Germany warns of some major challenges. To produce calcium oxide you have to burn chalk or limestone, producing CO₂ that must be stored.

Wolf-Gladrow has looked at an alternative: scattering the common mineral olivine as a powder in humid tropical lands. Olivine reacts with CO₂, but it could only remove at most 3.7 gigatons of CO₂ per year - around one-tenth of our annual emissions. Too much olivine would eventually leach into tropical rivers and make them more alkaline, harming wildlife.

My initial reaction was of the potential for damaging the marine ecosystem. In the paper, Kruger states:

It would thus bring various marine calcifying species, which depend in the buildup of their hard shells
or skeletons on the oversaturation of CaCO₃ in surface waters, into unfavorable environmental conditions, to which their degree of adaption is yet unknown. In the worst case their carbonate
parts might dissolve.

I would say that’s a pretty worst case” alright. But geoengineers say that these potential worst case scenarios should not prevent the public from even considering the options available. “A fear of unintended consequences which could arise from large-scale interventions in natural cycles may be seen to undermine the international commitment to reduce greenhouse gas emissions. This distrust should not prevent the objective consideration of the potential for geoengineering approaches so that they can be assessed based on factual evidence,” says Oxford Geoengineering.

The full article is available for free download here (PDF).

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APCI announces US-based electroceramic powder production operation

The firm announces the start-up of a U.S.-based ceramic powder manufacturing facility for the production of piezoelectric powders. Hammond Lead Products, a US-based chemical producer centered in Indiana, is working with APCI to match its lead-related materials science technologies with APCI’s array of established high performance lead-zirconate-titanate powders. These piezoelectric powders, as well as additional custom formulation products, will be available through APCI and HLP to customers for applications in commercial and defense-related markets. Expectations are for start up of this production installation before the end of 2009.

Raytheon receives industry award for energy innovation

The National Energy Resources Organization awarded Raytheon the 2009 Technology Innovation Award for recent work in the areas of renewable energy and green technology. The award was for research done by Frank Prautzsch and John Cogliandro. Prautzsch’s work involves using open and closed bed photobioreactors to raise algae using carbon dioxide flue gas as a feeder. The algae is then used to form biodiesel and other products. Cogliandro is currently developing a new patented disruptive technique to sequester carbon dioxide greenhouse gas using radio frequency energy and aerogel catalysts to convert the CO₂ to a solid in underground formations.

Cabot”s Nanogel aerogel insulation selected for 50 km of subsea pipelines

The aerogel Compression Packs consist of packs of compressed Nanogel with an integrated protective outer layer to provide durability and consistency of form. These packs are applied to sections of inner pipe (80-foot double joints for this project) and then expanded to their precise final forms prior to insertion of the insulated inner pipes into outer pipes. The integrated indexing of each panel enables field personnel to install the insulation quickly and precisely, without the need for special tools or equipment. The ultra-low conductivity of Nanogel aerogel is a key enabler of the flowline designs, which have specified U-values of 1.50 W/m(2) K while maintaining relatively small outer jacket pipes.

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Credit: Union of Concerned Scientists

Yes, Cap-and-Trade issues are a great concern to lots of individuals engaged in manufacturing ceramic and glass products. And, yes, the issues are also of great concern to lots of materials scientists, researchers and lab managers. The issue is getting hashed out in lots of meetings, particularly ones in Washington, DC, and it is increasingly likely that some carbon-related bill(s) will be wrapped up by the end of the year. Until then, there will be a lot of debate, hyperbole, spin and PR campaigns.

Having said that, it is worth noting that some MIT economists and tech experts have already weighed in on the matter and seemed to have clearly concluded in 2007 that once the initial “lurches” work through the economy, Cap-and-Trade shouldn’t be a big deal:

The MIT Emissions Prediction and Policy Analysis model is applied to synthetic policies that match key attributes of a set of cap-and-trade proposals being considered by the U.S. Congress in spring 2007. The bills fall into two groups: one specifies emissions reductions of 50% to 80% below 1990 levels by 2050; the other establishes a tightening target for emissions intensity and stipulates a time-path for a “safety valve” limit on the emission price that approximately stabilizes U.S. emissions at the 2008 level. Initial period prices are estimated between $7 and $50 per ton CO₂ with these prices rising by a factor of four by 2050. Welfare costs vary from near zero to less than 0.5% at the start, rising in the most stringent case to near 2% in 2050. If allowances were auctioned these proposals could produce revenue between $100 billion and $500 billion per year depending on the case. Outcomes from U.S. policies depend on mitigation effort abroad, and simulations are provided to illuminate terms-of-trade effects that influence the emissions prices and welfare effects, and even the environmental effectiveness, of U.S. actions. Sensitivity tests also are provided of several of key design features. Finally, the U.S. proposals, and the assumptions about effort elsewhere, are extended to 2100 to allow exploration of the potential role of these bills in the longer-term challenge of reducing climate change risk. Simulations show that the 50% to 80% targets are consistent with global goals of atmospheric stabilization at 450 to 550 ppmv CO₂ but only if other nations, including the developing countries, follow suit.

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World's list of top five CO2 emitters changes.

The world’s carbon dioxide emissions have escalated 38 percent since 1992, climbing from 6.1 billion tons in 1992 to 8.5 billion tons last year, according to DOE’s Carbon Dioxide Information Analysis Center, located at Oak Ridge National Labs. In 1992, the United States headed the list of the world’s top five CO₂ emitters. The rest of the list included (in order of CO₂ emissions) China, Russia, Japan and India, reports CDIAC’s Gregg Marland. “The source of emissions has shifted dramatically,” Marland now says, noting that increased manufacturing and rising energy demands in developing countries - particularly in China and India - have caused the list to be reordered since 1992. According to Marland, China moved to the top of the list in 2006, dropping the U.S. to second place. He says India surpassed Japan for fourth place in 2002 and, by the end of 2008, is expected to take over third place from Russia. This leaves the Soviets in fourth place, with Japan trailing at number five. Unfortunately, the CO₂ emissions race is one competition no nation wants to win.

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Every year, concrete accounts for more than five percent of human-created, pollution-causing carbon dioxide emissions, reports Technology Review, an online news source published by MIT. Most of these emissions are created because cement - the active ingredient in concrete - requires limestone and clay powders to be baked at extremely high temperatures, usually generated by burning fossil fuels. Additional emissions also are generated if heat and steam are used to accelerate curing. Carbon Sense Solutions Inc. in Halifax, Nova Scotia , says it has developed a process that will enable manufacturers of precast-concrete products to collect and store their factories’ CO₂ emissions in the products they manufacture.

CSS’ process does this by exposing concrete products to the CO₂ flue gas created during a factory’s curing process. CSS’s president Robert Niven explains that his firm’s technology exposes freshly mixed concrete to a stream of CO₂-rich flue gas, rapidly speeding up reactions between the gas and the calcium-containing minerals in cement. He estimates these minerals account for about 10 to 15 percent of the concrete’s volume and adds that his firm’s process also saves energy and reduces emissions by virtually eliminating any need for heat or steam during curing. If widely accepted, CSS’ still unproven technology has the potential to eliminate 20 percent of all cement-industry CO₂ emissions, he claims. “Considering that concrete is the most abundant man-made material on earth and how fast the precast market is growing,” Niven says, “the estimated carbon dioxide storage potential is 500 megatons a year.” He says 60 tons of CO₂ could be stored as solid limestone - or calcium carbonate - within every 1,000 tons of concrete produced and further claims that the end products produced will be less permeable to water, more durable and less likely to shrink or crack. Niven’s claims - and CSS’ new technology - will be tested in a pilot plant the firm expects to build in Nova Scotia later this year. Preliminary results are anticipated by the end of 2008.

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