The production of cement, an ingredient in concrete, accounts for roughly 8% of the world’s annual carbon dioxide emissions, making it a significant target of greenhouse gas emissions reduction goals.
The production of cement, an ingredient in concrete, accounts for roughly 8% of the world’s annual carbon dioxide emissions, making it a significant target of greenhouse gas emissions reduction goals. Toward those efforts, the Rice lab of chemist James Tour used flash Joule heating to remove toxic heavy metals from fly ash, a powdery byproduct of coal-based electric power plants that is used frequently in concrete mixtures. Using purified coal fly ash reduces the amount of cement needed and improves the concrete’s quality.
In the lab’s study, replacing 30% of the cement used to make a batch of concrete with purified coal fly ash improved the concrete’s strength and elasticity by 51% and 28%, respectively, while reducing greenhouse gas and heavy metal emissions by 30% and 41%, respectively, according to the paper published in the Nature journal Communications Engineering.
“Reducing emissions from cement production is very important to mitigate global greenhouse emissions,” said lead author Bing Deng, a postdoctoral research associate in the Tour lab. “This is the big picture of this study.”
Read more at: Rice University
Wei Meng (left) and Bing Deng are co-authors on the study. Deng holds a sample of cement made with coal fly ash purified through a flash Joule heating-based process. (Photo Credit: Gustavo Raskosky/Rice University)