“Green” cement “could cut CO2”

British engineers say they have developed a new kind of environmentally friendly cement that absorbs -- rather than emits -- large amounts of carbon dioxide (CO2) during production, the Guardian reported. The new magnesium silicates-based cement, which has attracted the attention of some construction companies and investors, could be on the market within five years.

Developed by a team of scientists led by Nikolaos Vlasopoulos of the engineering company Novacem, the product requires less heating than
regular cement and absorbs CO2 as it cools, making the process carbon-negative.  Scientists say that the "green" cement can absorb
0.6 tonnes of CO2 per tonne of cement, while standard cement production emits about 0.4 tonnes of CO2 per tonne of cement.

The London-based company has begun a US$2.2 million project to build a pilot plant, funded by the UK government-backed Technology Strategy

About 2 billion tonnes of cement are produced annually, generating 5% of the world’s CO2 emissions – exceeding the carbon output of the
aviation industry. Rising levels of CO2, a greenhouse gas, have been implicated in climate change. By 2020, the demand for cement is
expected to grow by 50%, according to a report by the French bank Credit Agricole.

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