As one of our most relied upon construction materials, concrete makes a significant contribution to our overall carbon emissions. Calcium-based substances are heated at high temperatures to form the cement, a process that produces carbon dioxide. But by slightly altering the quantities of materials used, scientists from MIT have uncovered a new method of cement mixing that could reduce these emissions by more than half.
Concrete is generally made by mixing gravel, water, sand and cement. To produce the cement, calcium-rich materials such as limestone are cooked up, typically with clay, at temperatures as high as 1,500° C (2,732° F). The energy required to heat up the mix combined with a resultant chemical reaction generates carbon dioxide, a process the researchers say is responsible for between five and ten percent of total industrial greenhouse gas emissions.
By examining the makeup of cement, the MIT team, led by senior research scientist Roland Pellenq, found that reducing the ratio of calcium to the silicate-rich clay substantially reduced the output of carbon dioxide. Typically, calcium to silica ratios can vary between 1.2 to 2.2, though 1.7 is seen as the standard for producing cement. By compiling a database that compared the chemical makeup of the different ratios, the researchers determined that 1.5 ratio was in fact the optimal mix. According to the researchers, this slight change in calcium levels could reduce carbon emissions by as much as 60 percent.
Furthermore, with the altered ratio the mix proved to have a higher resistance to fractures, with the researchers claiming this is due to the molecular structure transforming from a tightly ordered crystalline to a disordered glassy structure. Pellenq describes the mix of 1.5 to be "magical ratio," with twice the mechanical resistance to fractures of normal cement.
The analysis of the cement mix was carried out at a molecular level, meaning the team will need to conduct further research to make sure it can apply to engineering scale applications. Pellenq says the formula could find a home in oil and gas industries, where more resistant cement could be particularly useful in preventing leaks and blowouts.
The research was published in the journal Nature Communications.
Source: MIT
A textbook case for carbon taxes.
Despite the "proven science" of AGW, it has been one of the biggest non-scientific lies foisted upon the public that was ever created. The information caused many pro-AGW sites to start talking about the 1 year "hiatus" AGW has taken.
When confronted with this, the UN made a statement they would not abandon their work in making regulations about AGW giving the lame excuse that they just wanted to be sure.
Don;t just beleive someone telling you ADW is science. Become educated by doing your own research - on both sides of the issue. You will find the AGW crowd always has fudged their data/reports. So although the pseudo-science community may lad this concrete b/c of less emissions, in reality the point it moot. Either that or the palm trees the initial global warming "science" stated as absolute fact as being grown on the shores of Lake Erie by the year 2000 are of the invisible kind. I have been following the evolution of this argument and lie now since it was first started. All it has really done is filled a lot of bureaucrat's pockets with our tax dollars whilst giving more governmental control over our lives.
But please... if you believe this is wrong, prove it with some homework of your own that will include looking at the actual data instead of taking your professor's words. Secondhand knowledge can be (and in the case of pro-AGW ideas) as reliable as rumor. So although this post could be considered secondhand - at least I am willing to admit it and say prove it for yourself.
@Lbrewer42 I'm intrigued by how you intend to prove something using a lack of data. Lining pockets? That's all for the fossil fuel companies, who get 20 times as much for taking a dump in our atmosphere. Why would you ever think that's preferable?
And of course: "What if it's all a hoax and we made the world a better place for nothing?"