Wednesday, July 23. 2008A Concrete Fix to Global Warming (?)A new process stores carbon dioxide in precast concrete.
By Tyler Hamilton in MIT's Technology Review
Carbon dioxide in concrete: This micrograph shows the crystal structure of concrete cured in the presence of carbon dioxide. A Canadian company says that its curing process can store 60 tons of carbon dioxide inside 1,000 tons of precast concrete products, such as concrete blocks, while saving energy. A Canadian company says that it has developed a way for makers of precast concrete products to take all the carbon-dioxide emissions from their factories, as well as neighboring industrial facilities, and store them in the products that they produce by exposing concrete slurry to carbon-dioxide-rich flue gases during the curing process. Industry experts say that the technology is unproven but holds great potential if it works. Concrete accounts for more than 5 percent of human-caused carbon-dioxide emissions annually, mostly because cement, the active ingredient in concrete, is made by baking limestone and clay powders under intense heat that is generally produced by the burning of fossil fuels. Making finished concrete products--by mixing cement with water, sand, and gravel--creates additional emissions because heat and steam are often used to accelerate the curing process. But Robert Niven, founder of Halifax-based Carbon Sense Solutions, says that his company's process would actually allow precast concrete to store carbon dioxide. The company takes advantage of a natural process; carbon dioxide is already reabsorbed in concrete products over hundreds of years from natural chemical reactions. Freshly mixed concrete is exposed to a stream of carbon-dioxide-rich flue gas, rapidly speeding up the reactions between the gas and the calcium-containing minerals in cement (which represents about 10 to 15 percent of the concrete's volume). The technology also virtually eliminates the need for heat or steam, saving energy and emissions. Work is expected to begin on a pilot plant in the province of Nova Scotia this summer, with preliminary results expected by the end of the year. If it works and is widely adopted, it has the potential to sequester or avoid 20 percent of all cement-industry carbon-dioxide emissions, says Niven. "If the technology is commercialized as planned, it will revolutionize concrete manufacturing and mitigate hundreds of megatons of carbon dioxide each year, while providing manufacturers with a cheaper, greener, and superior product." He adds that 60 tons of carbon dioxide could be stored as solid limestone--or calcium carbonate--within every 1,000 tons of concrete produced. Further, he claims that the end product is more durable, more resistant to shrinking and cracking, and less permeable to water. "It almost sounds too good to be true," says civil engineer Rick Bohan, director of construction and manufacturing technologies at the Portland Cement Association, in Skokie, Illinois. He points out that the idea of concrete carbonation has been around for decades but has never been economical as a way to strengthen or improve the finished product. In the late 1990s, researchers showed how carbon dioxide could be turned into a supercritical fluid and injected into concrete to make it stronger, but the required high pressures made the process too energy intensive. Carbon Sense Solutions claims to achieve the same goal but under atmospheric pressure and without the need for special curing chambers. "I'd be really skeptical," adds Bohan. "But if someone has a revolutionary process, we'd love to see it." Precast concrete products represent between 10 and 15 percent of the North American cement and concrete market. While the figure in some European markets is 40 percent, most concrete is mixed and poured at construction sites outside the control of a factory setting (and Carbon Sense Solutions' process). "Considering concrete is the most abundant man-made material on earth, and that the precast market is growing, the estimated carbon dioxide storage potential of this is 500 megatons a year," Niven says. "That is on par with other global carbon dioxide mitigation solutions, such as carbon capture and geological storage." Research professor Tarun Naik, director of the University of Wisconsin-Milwaukee's Center for By-Products Utilization, says that all concrete absorbs carbon dioxide over time if left to cure naturally--but only up to a point. The gas usually penetrates the first one or two millimeters of the concrete's surface before forming a hard crust that blocks any further absorption. Naik says that something as simple as using less sand in a concrete mix can increase the porosity of the finished product and allow more ambient carbon dioxide to be absorbed into the concrete. It's simpler than Carbon Sense Solutions' accelerated curing process and can be applied to a much larger market, he says. Other groups are taking aim at emissions from the cement-making process itself. Researchers at MIT are seeking new ingredients in cement that are less energy intensive, while companies such as Montreal's CO2 Solution have an enzymatic approach that captures carbon-dioxide emissions from cement-factory flue stacks, converts the greenhouse gas into limestone, and feeds it back into the cement-making process. Calera, backed by venture capitalist Vinod Khosla, even claims that it can remove a ton of carbon dioxide from the environment for every ton of cement it produces. Copyright Technology Review 2008. Personal comment: Effet d'annonce ou réalité? A suivre... Tuesday, July 22. 2008Sun, Seine and artificial beachOn Monday the beach comes to Paris, and this year it's bigger than ever, expanding along canals and into the suburbs Saturday July 19, 2008 Inner city oasis ... deckchairs on the riverbank It is pure hedonism to want to transform a capital city into a seaside resort, bringing 2,000 tons of sand by boat, displaying more than a thousand deckchairs on its river banks, loaning 85 boats for people to sail for free, planting 950 trees in a single square and building 61 beach cabins on what is, for 335 days of the year, an expressway. The dapper and energetic city mayor Bertrand Delanoë started these Paris Plages in July 2002, a year after coming to office, and each summer they are copied by more and more cities around the world. The scheme has been expanded this summer to include more free activities, more palm trees, more concerts, more sand and more bamboo forest; and is about to be launched in many new Parisian locations. Aside from its original location on the Right Bank, from Pont Henri IV to Quai du Louvre, this year sand and entertainment can also be found in waterside spaces in the north-east of the French capital, along the three canals that lead up to the Villette basin, and from La Villette into various suburban towns. Paris Plages started life as a socialist fantasy: bring the beaches to those who can't afford summer holidays and create a bit of joie de vivre for the millions of tourists who make Paris the most visited city in the world. The car-hating mayor could think of no better place for the beach than the Voie Georges Pompidou, the expressway which hugs the Seine's curves, from the Eiffel Tower to the Gare de Lyon. It may seem an extravagant, potentially environmentally damaging exercise but the sand, which is brought in by boat, will be reused once the sand-castles have crumbled. The water fountains supply municipal water, drunk from free biodegradable goblets, for which 150 recycling bins have been provided, and the 950 trees planted at the place de l'Hôtel de Ville will all be replanted in Paris' municipal gardens. It was the 2003 heatwave that made the city beach such a popular fixture on the Paris calendar. Three million people, from backpackers to bourgeois Parisians, flocked to try the dozens of free activities on offer from Quai Henri IV to Quai du Louvre: pétanque, guinguettes (cafes turned dance venues), sculpture workshops, fitness lessons, a climbing wall and ping pong tables. Improvised cafes and ice-cream stalls were scattered between the parasols and palm trees along the stretch. Success brought more people each year and every summer revealed a string of new activities such as swimming in prefab pools and rowing on the Seine. This year, new activities include free fencing lessons at the Tuileries Tunnel and a mini-golf course at the place de l'Hôtel de Ville. Children will enjoy the new table football games (called "baby-foot" in French) placed opposite the tip of Île de la Cité, between Pont Neuf and Pont des Arts. Young dreamers with a taste for Parisian folklore may want to listen to Anne-Sophie Péron telling stories accompanied by accordionist Marcel (between Pont Marie and Pont Louis-Philippe). Parents can head for the library cabin, which offers 250 books on free loan, at the foot of Pont Marie. Last year, the sand stretched to the north-east of Paris along the Ourcq, Saint Denis and Saint Martin canals, designed by Napoleon in 1808 to bring water to the capital. This year, the beach attractions have been doubled using the entire stretch of La Villette basin, formerly known for its slaughterhouses and meat restaurants, where the canals open into a large basin in the 19th arrondissement. The 85 boats on free loan for sailing or punting, as well as pedalos, should attract visitors to this less visited part of Paris. The old abattoirs may have given way to the Science Museum and La Cité de la Musique but the brasseries remain unchanged. If you want a meaty treat between a scuba-diving lesson and a trampoline session, the belle-époque Boeuf Couronné brasserie on avenue Jean-Jaurès still serves the best bone marrow on toast. Perhaps even more importantly, this is the first year that Paris Plages is expanding beyond Paris towards the suburbs. Not quite the suburbs that set France on fire in November 2005, but quiet working-class and petit-bourgeois suburban towns on the Ourcq and Saint Denis canals: Pantin, Bobigny, Noisy-le-Sec, Bondy, Aulnay-sous-Bois and Sevran where scuba-diving, kayaking, canoeing and sailing will be taught for free. Paris Plages kicks off on July 21 at 6.30pm with a free concert of Beethoven's Ninth Symphony performed by the Ensemble Orchestra of Paris with a 120-strong choir on Place de L'Hôtel de Ville. Just after the concert there will be a 3km-long picnic. The supermarket Monoprix, one of the event's 10 invisible sponsors (they are not allowed to advertise their brand anywhere on the sites, but have provided three quarters of the €2m budget), will provide picnic kits - a neatly packed biodegradable basket with cardboard plate, cup, cutlery and napkin - and a 3km-long tablecloth spread like a blanket, as an invitation to passers-by to join the picnic. There is a saying in French that, in August, Paris is a desert inhabited by tourists and the last eccentrics. Perhaps that's who Paris Plages was always intended for. However, as with Vélib, the free bicycle scheme launched last summer to a resounding success, it is likely to thrill both tourists and Parisians. Indeed many French political observers believe that hedonistic schemes like Paris Plages and Vélib may help lead Bertrand Delanoë to the Presidency in four years' time. ·Paris Plages (paris.fr) open July 21-August 21. Concerts organised by FNAC (fnaclive.com/festival-fnac-indetendances) every Friday and Saturday 5pm-10pm between Pont Marie and Pont de Sully. Eurostar (eurostar.com) London-Paris from £59 return. Montmartre Studio Lofts (montmartreparis.com) apartment in the So-Pi neighbourhood, south of Pigalle from €200 per night (Sleeps 2). Man made "borealis" - dropplets screenby Dan Gould A standout at the recent GLOW festival in Santa Monica was Usman Haque’s mind blowing art installation called Primal Source. Looking like the northern lights or a supernova on the beach, Primal Source was made up of a huge water spray screen with a rear projected light patterns. The changing display was controlled by crowd reaction and ambient noise. Microphones spread around the outside of the display picked up the cheers and shouts of the crowd which were then translated into the patterns and colors on the water screen. Check out the video below. -
- [via Notcot]
Posted by Patrick Keller
in Design
at
09:04
Defined tags for this entry: architects, communication, design, design (interactions), installations
Research, nanotech sensorsHP's grand vision: measure everythingPerhaps the world's most ambitious nanotech project is underway at Hewlett-Packard. Stan Williams' lab aims to build 'a central nervous system for the earth.'By David Kirkpatrick, senior editor
Last Updated: July 18, 2008: 11:34 AM EDT
NEW YORK (Fortune) -- Imagine walking down the supermarket aisle with a cheap device you could hold up to a tomato. If the sensor detects a pesticide residue, you'd know the "organic" label is a lie. Similar tools could track the chemical content of water in a stream, telling you if there was lead contamination and when it got there, or keep constant watch on a bridge and tell if a structural steel beam was at risk of collapse. Such products are almost certain to become common in coming decades, according to Stan Williams, who heads Hewlett-Packard's Information and Quantum Systems Laboratory. He aims to develop a panoply of microscopic-scale nanotech devices that will be able to measure essentially anything - and at low cost to boot. Viruses, bacteria, the chemical composition of molecules, vibration, moisture levels, particular sounds - these are just some of the things that the super-cheap devices he envisions will be able to detect. In an exclusive conversation with Fortune, Williams described in detail a project HP (HPQ, Fortune 500) began way back in 1994. He will speak about it in public for the first time next week at Fortune's Brainstorm Tech conference. No other company he knows of is developing similar products. "The theme for the lab is CeNSE - for Central Nervous System for the Earth," he says. Williams feels such a grandiose name is justified. Because these sensors will be built with standard semiconductor technology, they will ultimately be cheap enough to build "in the trillions." That will make it possible to deploy arrays of measuring devices anywhere at a reasonable cost. In our era of rapidly decaying global environment, such tools could help us know with certainty how our world is changing, and help us make better-informed choices about how to respond. Applying these devices to monitor the entire planet will take time. None of these nano-sensors will even come into existence for at least two years, and will not be deployed in quantity for 5-10 years. Before we monitor the planet we will likely use those sensors to monitor the strength of a bridge's beams. Others might maintain vigilance over a high-rise building's structure, or the steel in a ship's hull or a train track. The first versions, emerging in the next several years, will be expensive and are likely to be used to monitor systems in oil and gas refineries and chemical plants, where investments in monitoring vibration and chemical composition will pay off the most. "Think of our sensors as stethoscopes," says Williams. "As soon as something started vibrating a little bit differently we'd know it." HP has two fundamental types of nano-sensors under development in its lab. The first is a type of measurement device made from a relatively small number of atoms. Because of its small size, even the tiniest changes in the environment can perturb it. And that perturbance can be measured. "When you are able to craft matter at the nanometer scale," says Williams, "you have essentially achieved the ultimate level of control over directing matter, electrons or photons." Such devices would be able to measure minute amounts of biological material, or ultra-tiny vibrations, with tremendous sensitivity. "We're working on being able to detect individual molecules of whatever you may be concerned about - or individual viruses or bacteria," Williams says. Because these silicon-fabricated nano-measurers can be put by the millions onto one tiny chip, some of the products HP envisions resemble a nose - with multiple receptors for various "smells." But another nano-device that Williams has high hopes for would be optical: "A very tiny laser would light up and we could look at the optical spectra of chemicals. Each one is like a fingerprint, with a unique spectral identity. That would be a single universal detector." Though a laser capable of such a task would today cost around $100, Williams thinks they can eventually be produced for about 10 cents. HP already has working prototypes of various sorts of nano-detectors working in its 90-person lab. The company would likely license the sensor designs to others and buy back the devices to integrate into its own measurement and control information systems. Only once such sensors are combined with sophisticated database and analysis technologies can their promise be delivered. HP sees its business opportunity in helping customers manage the vastly greater amount of information such monitoring will generate. While Williams is confident HP has a huge head start (and he's not afraid to talk about the project -"We welcome competition," he says), this work can only proceed so fast. There simply aren't enough capable engineers in this highly rarified field, he says. Though the pathway is starting to seem clear, it remains long.
Posted by Patrick Keller
in Science & technology
at
08:34
Defined tags for this entry: monitoring, nanotech, research, science & technology, surveillance, territory
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fabric | rblgThis blog is the survey website of fabric | ch - studio for architecture, interaction and research. We curate and reblog articles, researches, writings, exhibitions and projects that we notice and find interesting during our everyday practice and readings. Most articles concern the intertwined fields of architecture, territory, art, interaction design, thinking and science. From time to time, we also publish documentation about our own work and research, immersed among these related resources and inspirations. This website is used by fabric | ch as archive, references and resources. It is shared with all those interested in the same topics as we are, in the hope that they will also find valuable references and content in it.
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