Shrimp shells harnessed to strengthen cement

Reporting in Cement and Concrete Composites, a team of Washington State University and Pacific Northwest National Laboratory researchers created nanocrystals and nanofibres of chitin from waste shrimp shells to add to cement. As well as making the material stronger, the team found that the set time for the cement was delayed by over an hour, which is advantageous for long-distance transport and hot weather concrete work.

“The concrete industry is under pressure to reduce its carbon emissions from the production of cement,” said Somayeh Nassiri, an associate professor at the University of California, Davis, who led the research at WSU. “By developing these novel admixtures that enhance the strength of concrete, we can help reduce the amount of required cement and lower the carbon emissions of concrete.”

Cement production comprises about 15 per cent of industrial energy consumption and about five per cent of total greenhouse gas emissions worldwide. High consumption of the material is also partly driven by the challenge of durability — concrete cracks easily and must be repaired or replaced often, Nassiri said in a statement.