Queensland concrete goes green

The SMH has an article on a “green concrete" producer in Queensland - Queensland concrete goes green.

A Toowoomba-based companys carbon emissions-free concrete could be the latest weapon in the fight against carbon emissions. Wagners CFTs Queensland-made "green concrete" has already been used in Brisbane and Toowoomba footpaths and has been recognised by the state governments ClimateSmart program.

In the companys home city, the "earth-friendly concrete" has been trialled in some building slabs and it is estimated the concrete could save 9.2 tonnes of carbon emissions in every 300 square metre slab. If it was used in every house slab that went down in Queensland, it could save about 270,000 tonnes of greenhouse gas emissions a year.

Wagners general manager Michael Kemp said the carbon-free concrete used two very common waste products with very little carbon; fly ash and slag from blast furnaces On Friday, his product development crew took out the biggest environmental award at the Premiers Climatesmart Sustainability Awards.

The more commonly used Portland cement is limestone and the carbon has to be "driven-off" the fine, grey cement so it can be mixed with the concrete.

"That process of making the cement creates the massive carbon dioxide emissions associated with concrete," Mr Kemp said. "In a typical house in Queensland for example, using our concrete at market as opposed to traditional concrete, in one housing slab you will save 9500 kilograms of carbon dioxide. "There are something like 30,000 homes built a year in southeast Queensland, so when you do the maths, the potential savings for carbon dioxide is massive."