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1margd
I used to tease a PhD engineer friend who specialized in cement and concrete (nukes) for having the most boring possible trade magazine. I've since learned that Romans had secret recipe that allowed their structures to persist all these years. Now, a new stronger cement that traps carbon. Methinks I owe my friend an apology!
This concrete can trap CO2 emissions forever
Bronte Lord | June 12, 2018
...concrete has an emissions problem. Its essential ingredient, cement, has a huge carbon footprint.
Cement is the glue that makes concrete strong, but the process of making cement requires superheating calcium carbonate, or limestone, and releases massive amounts of carbon dioxide into the atmosphere.
Cement is responsible for 7% of global man-made greenhouse emissions, making it the world's second largest industrial source of carbon dioxide, according to the International Energy Agency. Data from the United States Geological Survey -- the scientific agency of the US government -- reveals that global cement production was responsible for about 4 billion pounds of CO2 emissions in 2017 alone.
But a Canadian startup has invented a new system for making concrete that traps CO2 emissions forever and at the same time reduces the need for cement.
CarbonCure's system takes captured CO2 and injects it into concrete as it's being mixed. Once the concrete hardens, that carbon is sequestered forever. Even if the building is torn down, the carbon stays put. That's because it reacts with the concrete and becomes a mineral.
CarbonCure's system takes CO2 and injects it into concrete as it's being mixed.
"The best thing about it is the mineral itself improves the compressive strength of the concrete," Christie Gamble, the director of sustainability at CarbonCure, told CNNMoney.
"Because the CO2 actually helps to make the concrete stronger, concrete producers can still make concrete as strong as they need to but use less cement in the process."
And using less cement is how producers can really reduce emissions...
http://money.cnn.com/2018/06/12/technology/concrete-carboncure/index.html
This concrete can trap CO2 emissions forever
Bronte Lord | June 12, 2018
...concrete has an emissions problem. Its essential ingredient, cement, has a huge carbon footprint.
Cement is the glue that makes concrete strong, but the process of making cement requires superheating calcium carbonate, or limestone, and releases massive amounts of carbon dioxide into the atmosphere.
Cement is responsible for 7% of global man-made greenhouse emissions, making it the world's second largest industrial source of carbon dioxide, according to the International Energy Agency. Data from the United States Geological Survey -- the scientific agency of the US government -- reveals that global cement production was responsible for about 4 billion pounds of CO2 emissions in 2017 alone.
But a Canadian startup has invented a new system for making concrete that traps CO2 emissions forever and at the same time reduces the need for cement.
CarbonCure's system takes captured CO2 and injects it into concrete as it's being mixed. Once the concrete hardens, that carbon is sequestered forever. Even if the building is torn down, the carbon stays put. That's because it reacts with the concrete and becomes a mineral.
CarbonCure's system takes CO2 and injects it into concrete as it's being mixed.
"The best thing about it is the mineral itself improves the compressive strength of the concrete," Christie Gamble, the director of sustainability at CarbonCure, told CNNMoney.
"Because the CO2 actually helps to make the concrete stronger, concrete producers can still make concrete as strong as they need to but use less cement in the process."
And using less cement is how producers can really reduce emissions...
http://money.cnn.com/2018/06/12/technology/concrete-carboncure/index.html
22wonderY
The battle to curb our appetite for concrete
Add in the sand and gravel used in land reclamation, coastal developments and roads - and the current annual consumption rises to 40 billion tonnes.
This is twice the yearly amount of sediment carried by the world's rivers. In other words, we're using up sand faster than nature is creating it.
Options?
- In Australia, engineering firm Fibercon has developed a technology that uses recycled plastic for reinforcing concrete instead of the traditional steel mesh - this is now being used in footpaths.
Fibercon says by using 100% recycled plastic, the plastic-reinforced concrete gives a 90% reduction in CO2 compared to conventional steel mesh-reinforced concrete.
- At Exeter University, researchers are using nano-engineering technology to add graphene to concrete - making it twice as strong and four times more water-resistant than conventional concrete.
This new graphene-reinforced concrete also has huge efficiency savings, cutting the raw materials required to make concrete by some 50%.
- Another approach that could revolutionise the industry is the 3D printing of houses.
Because there's no penalty for over-designing a building, architects often err on the side of safety and buildings can contain 40% more concrete than they need.
One way of stopping this is by 3D printing buildings, creating concrete shapes directly from an architect's design.
- Canadian firm CarbonCure has developed a way of locking in more carbon by injecting liquefied CO2 into wet concrete.
Not only is the concrete stronger, the firm says it could save up to 700 million tonnes of CO2 emissions a year. So far, 100 producers have adopted the technology
Add in the sand and gravel used in land reclamation, coastal developments and roads - and the current annual consumption rises to 40 billion tonnes.
This is twice the yearly amount of sediment carried by the world's rivers. In other words, we're using up sand faster than nature is creating it.
Options?
- In Australia, engineering firm Fibercon has developed a technology that uses recycled plastic for reinforcing concrete instead of the traditional steel mesh - this is now being used in footpaths.
Fibercon says by using 100% recycled plastic, the plastic-reinforced concrete gives a 90% reduction in CO2 compared to conventional steel mesh-reinforced concrete.
- At Exeter University, researchers are using nano-engineering technology to add graphene to concrete - making it twice as strong and four times more water-resistant than conventional concrete.
This new graphene-reinforced concrete also has huge efficiency savings, cutting the raw materials required to make concrete by some 50%.
- Another approach that could revolutionise the industry is the 3D printing of houses.
Because there's no penalty for over-designing a building, architects often err on the side of safety and buildings can contain 40% more concrete than they need.
One way of stopping this is by 3D printing buildings, creating concrete shapes directly from an architect's design.
- Canadian firm CarbonCure has developed a way of locking in more carbon by injecting liquefied CO2 into wet concrete.
Not only is the concrete stronger, the firm says it could save up to 700 million tonnes of CO2 emissions a year. So far, 100 producers have adopted the technology
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