Green Cement

SF gate via Truthout:

To make traditional cement, limestone is heated to more than 1,000 degrees Celsius, which turns it into lime - the principal ingredient in Portland cement - and CO2, which is released into the air.

Constantz uses a different approach, the details of which remains secret pending publication of his patent.

At his pilot factory, a former magnesium hydroxide facility that made metal for World War II bombs, magnesium crunches underfoot as Constantz, wearing a pressed, blue button-down shirt with rumpled shorts and sandals, outlines how the process works.

He pointed to two enormous smokestacks billowing flue gases full of carbon dioxide next door at Dynegy, one of the West's biggest and cleanest power plants.

Constantz takes that exhaust gas and bubbles it through seawater pumped from across the highway. The chemical process creates the key ingredient for his green cement and allows him to sequester a half ton of carbon dioxide from the smokestacks in every ton of cement he makes.

Constantz believes his cement would tackle global warming on two fronts. It would eliminate the need to heat limestone, which releases CO2. And harmful emissions can be siphoned away from power plants and locked into the cement.

The same process can also be used to make an alternative to aggregate - the sand and gravel - that makes up concrete and asphalt, which would sequester even more carbon dioxide from power plants.

"The beauty here is we're taking this old industrial polluting infrastructure and turning it into something that will save the environment," Constantz said.

Doom, Gloom, and lots and lots of CO2

from the October 11, 2007 edition of the Christian Science Monitor:

A key threshold crossed

An Intergovernmental Panel on Climate Change report to be released next month will show that the limit on greenhouse-gases scientists hoped to avert has already been surpassed.

By Gregory M. Lamb

In Ray Bradbury's science fiction novel "Fahrenheit 451," that number represented the temperature at which books would burn, a symbol of a disturbing future under a totalitarian government.

For climate scientists, a similar number, 450 parts per million (ppm), holds its own ominous meaning. It represents a dangerous concentration of greenhouse gases in the atmosphere; a total that they were not expecting to be passed for at least another decade.

But a new UN-sponsored report, to be released next month, will show that as of 2005 the concentration of greenhouse gases in the atmosphere had already reached 455 ppm, according to Tim Flannery, a prominent Australian climate scientist who says he's seen the raw data that go into the document.

In an interview on Australian television this week, Dr. Flannery said that an Intergovernmental Panel on Climate Change (IPCC) report will show that carbon dioxide (CO2), nitrous oxide, methane, hydrofluorocarbons (HFCs), and other greenhouse gasses are at much higher concentrations than previously thought. Reuters quotes him:

"We thought we'd be at that threshold within about a decade.... We thought we had that much time. But the new data indicates that in about mid-2005 we crossed that threshold.... What the report establishes is that the amount of greenhouse gas in the atmosphere is already above the threshold that could potentially cause dangerous climate change."

About 75 percent of the total ppm represents carbon dioxide, associated with burning fossil fuels. The rest is a combination of the other gasses, he said.

On the Sierra Club website, blogger Pat Joseph explains the meaning of 450 ppm:

"450 ppm has long been held up as the threshold we dare not cross if we hope [to] avert the worst consequences of warming. Well, if Flannery is right, (and there's no reason to think otherwise) we crossed that line without even breaking stride."How did it happen? For one thing, countries such as China and India are actually "recarbonizing," Mr. Joseph says, meaning that their economies are becoming more energy-intensive "as they turn increasingly to [greenhouse-gas emitting] coal to feed their growth."

In May, the IPCC estimated current concentration of greenhouse gases at only 425 ppm, said a BBC report at the time. It noted that many scientists equated 450 ppm with a 2 degree C (3.6 degrees F.) rise in temperatures. Allowing temperatures to rise more than 2 C could lead to major impacts on the environment, scientists said. In the article, Rajendra Pachauri, the chairman of the IPCC, explained the strategy this way:

"If you want to stabilise around 450 ppm, that means in a decade or two you have to start reducing emissions far below the current level.... So in other words, we have a very short window for turning around the trend we have in rising greenhouse gas emissions. We don't have the luxury of time."

But, says Flannery, named Australian of the Year for 2007, that window is closed. According to the Australian Associated Press he says that higher figure is due to miscalculating the potency of other greenhouse gasses, which are included in the 450 ppm figure and measured in terms equivalent to that of CO2. But he adds:

"[A]lso we have really seen an unexpected acceleration in the rate of accumulation of CO 2 itself, and that's been beyond the limits of projection ... beyond the worst-case scenario. We are already at great risk of dangerous climate change – that's what the new figures say.... It's not next year, or next decade; it's now."

A major UN climate change meeting in Bali, Indonesia, in December aims to set a course toward a new global agreement to reduce greenhouse-gas emissions. The current Kyoto Protocol, signed by the majority of the world's nations but not the United States, expires in 2012. Flannery told Reuters that the 450 ppm figure adds to the urgency and importance of that meeting.

Meanwhile, Erwin Jackson, policy director of the Climate Institute, an Australian environmental group, told the Australian Associated Press that reducing greenhouse gas levels would be the only path to avoiding a catastrophe:

"The longer we stay above the kind of levels we're at at the moment, the more likely it is that we would start to see the loss of the Great Barrier Reef; you would actually start see the collapse of the great ice sheets and places like the Amazon starting to burn down."This weekly feature appears with links at csmonitor.com

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Amazing Science Updates

from physorg.com:

• Tiny Ceramic Tubes could make power plant's CO2 reusable.
• The attractive Casimer force can be reversed - creating repulsion between two objects.
• Fujitsu develops the potential for 1.2 Terrabits in a 2.5" hard drive.
• Adding tiny boric acid particle to oil reduces its friction by two thirds!
• Under a strong magnetic field, vacuum might act as a hypothetical pseudoscalar particle, making hypothetical Dark Matter unnecessary.
  

Meat as a major energy drain and source of CO2

from New Scientist: Environment:

Meat is Murder on the Environment
18 July 2007
Newscientist.com news service
Daniele Fanelli

A kilogram of beef is responsible for more greenhouse gas emissions and other pollution than driving for 3 hours while leaving all the lights on back home.

This is among the conclusions of a study by Akifumi Ogino of the National Institute of Livestock and Grassland Science in Tsukuba, Japan, and colleagues, which has assessed the effects of beef production on global warming, water acidification and eutrophication, and energy consumption. The team looked at calf production, focusing on animal management and the effects of producing and transporting feed. By combining this information with data from their earlier studies on the impact of beef fattening systems, the researchers were able to calculate the total environmental load of a portion of beef.

Their analysis showed that producing a kilogram of beef leads to the emission of greenhouse gases with a warming potential equivalent to 36.4 kilograms of carbon dioxide. It also releases fertilising compounds equivalent to 340 grams of sulphur dioxide and 59 grams of phosphate, and consumes 169 megajoules of energy (Animal Science Journal, DOI: 10.1111/j.1740-0929.2007.00457.x). In other words, a kilogram of beef is responsible for the equivalent of the amount of CO₂ emitted by the average European car every 250 kilometres, and burns enough energy to light a 100-watt bulb for nearly 20 days.

The calculations, which are based on standard industrial methods of meat production in Japan, did not include the impact of managing farm infrastructure and transporting the meat, so the total environmental load is higher than the study suggests.

Most of the greenhouse gas emissions are in the form of methane released from the animals' digestive systems, while the acid and fertilising substances come primarily from their waste. Over two-thirds of the energy goes towards producing and transporting the animals' feed.

Possible interventions, the authors suggest, include better waste management and shortening the interval between calving by one month. This latter measure could reduce the total environmental load by nearly 6 per cent. A Swedish study in 2003 suggested that organic beef, raised on grass rather than concentrated feed, emits 40 per cent less greenhouse gases and consumes 85 per cent less energy.

"Methane emissions from beef cattle are declining, thanks to innovations in feeding practices," says Karen Batra of the National Cattlemen's Beef Association in Centennial, Colorado. "Everybody is trying to come up with different ways to reduce carbon footprints," says Su Taylor of the Vegetarian Society in the UK: "But one of the easiest things you can do is to stop eating meat."

From issue 2613 of New Scientist magazine, 18 July 2007, page 15