Even as a builder you have a tendency not to realize the complexities of products in a modern home. One that I’m sure few of us understand well is concrete. OK so you mix some sand and cement together, add a bit of water and boom there it is.
Hmmm when you dig deeper, you’ll be surprised how complex it is! Cement referred to sometimes as Portland cement, is made from natural raw materials like Calcium Carbonate (Limestone, coral or Chalk), Silica, Alumina and Iron oxide (mainly in the forms of clay and shale) which is all ground together, then feed into a rotating kiln. These kilns reach an approx temperature of 1500 degrees Celsius. Out the other side comes ceramic like balls that are known as Clinker! The clinker then cools slightly and then is finely ground with a small amount of gypsum and then we have Cement. Wow there a process you take for granted.
By the way, Portland cement doesn’t come from the American city Portland. The name comes from the large production hub in the early 1900’s which was on isle of Portland area in Dorset, England. The raw material early year was made from Portland Stone, lots more pointless trivia for this weekend’s BBQ for you.
Australia now produces some of its own cement which is good but as you can see its quite and intensive process, both from a raw resources and a power and energy point of view.
So what’s being done to change that?
Companies like Boral are working towards refining the processes to change the product mixes to reduce the impacts.
So like what?
In the innovation house we are using a product called envirocrete.
How is it different?
Well in its concrete mix, it uses 70 % cement and 30% Fly ash, then adds them to the other parts like aggregates and water to make concrete.
What’s fly Ash?
It’s a waste material from coal fired power stations (of which we have a few of in NQ!) .
That’s pretty cool!
So buy using some waste materials we get good reduction in our impact (read Carbon emissions) and the product is great, it’s Grey and Hard, everything you want in concrete.
Come and check it out at some stage when we get it finished.