Researchers at the University of Illinois Chicago (UIC) and their collaborators received two federal grant awards to support investigating new methods to reduce carbon dioxide emissions from cement manufacturing.
The first award is $2.3 million from the Department of Energy in support of research to develop a carbon-negative replacement for portland cement. A proposed project from UIC, the University of Wisconsin-Madison and Pennsylvania State University, uses carbon captured from the air through a process called distributed direct air capture with rapid mineral carbonation to convert industrial mineral wastes into a recyclable replacement for portland cement. The objective is to create a durable and versatile building material that permanently stores C02 through a process that pulls more carbon out of the air than is emitted.
The second award is $1.9 million from the National Science Foundation to UIC, University of Wisconsin-Madison and Fort Lewis College, will support the development of a sustainable way to produce calcium hydroxide, a critical ingredient for creating cement.
The process under development is known as LoTECH, for low-temperature calcium hydroxide process. It uses a low-temperature ammonia cycle to produce calcium hydroxide from industrial waste streams, such as crushed concrete and coal ashes. As a result, cement could be made into concrete in small, distributed plants or portable units. The LoTECH system also has potential to shorten supply chains and promote sustainability in the concrete industry.
“You can think of this as a closed-looped, modular process,” said Meenesh Singh, assistant professor of chemical engineering at the UIC College of Engineering and co-principal investigator of the NSF award. “It can be placed in the back of a truck, and wherever you have a supply of concrete after a building is demolished, this system can harvest the waste product and then manufacture new cement right on site.”