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trueHUE® Water cooler stories
Cement’s contribution to emissions is especially immense because of the chemical process required to make it.
About two-thirds of the polluting gases that come from cement production stem from burning limestone. Kilns are heated to more than 1,400 degrees Celsius (2,600 Fahrenheit), about four times hotter than a home oven set to the self-clean cycle. Inside the kiln, carbon trapped in the limestone combines with oxygen and is released as CO2, the most abundant greenhouse gas.
A ton of cement yields at least half a ton of CO2, according to the European Cement Association. That’s more than the average car would produce on a drive from New York to Miami. And a single mixer truck can carry about 13 tons. Hundred
The IEA estimates cement production will rise 12% to 23% by 2050, though it could cut emissions with a series of actions.
“There are cement products with lower environmental impact, but they usually cost more than the normal ones,”
Cost is a problem because greener forms of cement can cost triple what the traditional mix does. Researchers led by Brett Tempest at the University of North Carolina at Charlotte found a yard of geopolymer cement may reach $161, while the most commonly used Portland variety is $51, their 2015 paper in the PCI Journal published by the Precast Concrete Institute.
The European Cement Association says its producers already get 44% of their energy from cleaner sources and wants to raise that proportion to 60% by 2050. Instead of using coal, it’s creating heat with used tires, mineral oil and industrial waste.