Concrete CO2 reduction

When businesses trying to reduce their emissions talk about concrete results, they’re generally not being literal. But for a pair of Spanish companies, Tecnalia and the Consejo Superior de Investigaciones Científicas (CSIC), their recently patented technology will do almost exactly that: using the solid waste from thermal power plants in place of limestone.

In cement production, limestone is heated up with other materials like clay, releasing the carbon dioxide from limestone to create calcium oxide, or quicklime. It’s this quicklime that is ultimately mixed with other materials and ground with gypsum to form cement.

By removing limestone from the process and replacing it with existing waste from thermal plants, which has been enhanced using nanomaterials, both energy and cement production benefit from recycling. The release linked above also boasts that the process reduces the energy required in the process by 50 per cent.

Of course, reducing the CO2 emissions from one industrial activity doesn’t exactly make the process emission-free. In Canada, despite our heavy use of hydro power, thermal power accounts for about 23 per cent of our total electricity production. Electricity production, in turn, is responsible for about 22 per cent of the country’s CO2 emissions.

Still, any technology that makes better use of the waste these plants are producing anyway makes sense in the short term. According to The Cement Association of Canada, the cement industry currently accounts for 1.4 per cent of the country’s greenhouse gas emissions.

Everyone wants to see concrete results on our environmental record, because the future of our planet is heavy, heavy stuff.