According to the US Department of Agriculture, approximately 412,769 tonnes of discarded eggshells must be transported and disposed of in the US alone every year. Now scientists at the University of Aveiro in Portugal have developed a method of using this eggshell waste in the production of ceramics.
The process involves incorporating crushed eggshells into a ceramic slurry which is subsequently processed “according to a specific protocol that includes a 3-cycle cooking phase”.
Porous pavement made from the slurry exhibits desirable qualities such as porosity and water absorption.
As well as keeping egg shells out of landfills, the process would avoid the environmental damage caused by mining calcite which is the usual source of the calcium in ceramic goods.