Study Turns Waste into Cementitious Materials
A research team from the Missouri University of Science and Technology (Missouri S&T) has recently been awarded a grant to turn waste products into supplementary cementitious materials.
“Years ago, SCMs were used as a cheap option to replace some Portland cement and also have a stronger and more durable concrete mixture,” said Dr. Hongyan Ma, associate professor of civil engineering and Director the university of Laboratory of Future Cements and Carbon-Negative Initiatives.
“There is now a severe shortage of these materials, so my team is looking at creative ways to develop new alternatives that are carbon-negative and will make the industry greener.”
About the Project
The two-year research project received a $2 million grant from the U.S. Department of Energy and $500,000 in funds from the university and industry partners. It reportedly aims to make this unusable waste into something of value.
Ma adds that one of the most common SCMs has traditionally been coal combustion residue, or fly ash, but a large percentage of this type of waste is not currently usable in cement.
Carbon negative cement from ash - https://t.co/3Y8qn1ES96— Carl DuPoldt (@CarlDupoldt) November 10, 2023
According to the Electric Power Research Institute, 2.5 billion tons of this type of waste have been disposed of in ponds and landfills throughout the United States.
The research will also reportedly cover the ash from municipal solid waste incinerators, steel slag, recycled concrete and other waste products. The team is currently developing processes to break down the structure of the solid wastes in ways that will also allow them to store carbon dioxide.
The carbon that is combined with these new SCMs will primarily come from the flue gases of power plants and the manufacturing industry, Ma explains.
By using CO2 directly from the flue gasses, as long as the concentration is high enough, his team will not have to use energy-intensive carbon-capture methods.
Ma says this project is designed to make a significant difference in the concrete industry in the near future, as opposed to focusing on more general, long-term concepts.
“The work we are conducting is mission-oriented,” he said. “Part of our research is to make sure what we develop is economically feasible. It can’t be too expensive, as it needs to be a realistic option to support the supply chain.”
While Ma is the project’s principal investigator, his co-PIs are Dr. Aditya Kumar, associate professor of materials science and engineering; Dr. Mahelet Fikru, associate professor of economics; and Dr. Wenyu Liao, assistant research professor of civil engineering.
Lawrence Livermore National Laboratory is also collaborating with S&T for the project, the university says.
Other Missouri S&T Concrete Research
Earlier this year, in February, a team was working to make the 3D printing of concrete faster, stronger and more resilient for the U.S. Army Corps of Engineers.
According to the university’s release, researchers are working on two projects funded by grants, including $320,000 through the Corps.
This project began in April 2022 and will reportedly last four years, examining three different strength classes of concrete and developing quality-control test methods for 3D printing.
The second grant, totaling $360,000 and awarded to S&T through Florida International University, was awarded in the fall of 2022 and will be ongoing until August 2025.
This project examines ultra-high-performance concrete and how it can be used for 3D printing with three different construction methods: layer-by-layer, sprayed concrete and stay-in-place formwork systems.
Dr. Kamal Khayat, S&T’s Vice Chancellor for Research and Innovation, anticipates that this type of 3D printing construction will be of “great benefit” to the U.S. military and construction companies. Additionally, he notes that this type of construction is the “way of the future.”