Being one of the most common construction materials, concrete makes up a large percentage of the world’s carbon emissions. In a time when all must be done to cut these emissions, it is imperative that this percentage is brought down. Simple solutions might be best, and once such solution could be the new formula for making cement, which a team of scientists at MIT have recently come up with and which could cut these emissions in half.
The standard formula for making concrete is mixing together gravel, water, sand and cement. To make the actual cement, calcium-rich materials like limestone are heated up at temperatures as high as 2,732° F. This, combined with the chemical reaction it causes, creates carbon dioxide and research shows that this entire process is responsible for five to ten percent of total industrial greenhouse gas emissions.
The team of MIT researchers now discovered that by reducing the ratio of calcium to the silicate-rich clay in the current formula, led to a reduction of carbon dioxide emissions by nearly 60 percent, which is quite a significant number. They found that the optimal ratio of calcium to silica is 1.5, while the current standard ratio is 1.7.
The team also discovered that the concrete made using the new formula is twice as resistant to fractures as normal cement, which according to the researchers is the result of its molecular structure, which is not the traditional tightly ordered crystalline, but a more disordered glassy structure.
So far, all the analysis of this new cement formula has been done on the molecular level. They are now getting ready to start testing it on a larger scale, to make sure it is applicable in the real world. The researchers are sure that, if proven reliable, the formula could would be very useful in the oil and gas industries, where more resistant cement could go a along way towards preventing blowouts and leaks.