Recycling of bone ash from animal wastes and by-products in the production of novel cements

The purpose of this research is to demonstrate the utilization of animal wastes and by-products in the production of low-energy and low-CO₂ clinkers and cements in order to preserve natural resources, such as limestone, while reducing CO₂ emissions released from the cement manufacturing process and reducing potential health risk to the world population (such as bovine spongiform encephalopathy or other health issues…). Pure calcium sulfoaluminate clinker was produced with calcium hydroxide, aluminum hydroxide, and calcium sulfate hemihydrate; followed by additional clinkers produced from substituting calcium hydroxide with bone ash (from 0 to 100% of the calcium hydroxide replaced). The final clinkers contained various amounts of ye'elimite, calcium aluminate phases, as well as tricalcium phosphate, depending on the firing temperature. Finally, some preliminary results on the hydration process and compressive strength are provided for the production of these binders.