impact mixing

The powdered slag and other materials are poured into a mixer that looks like a big food blender. The dry ingredients are pressed together — what Hughes calls “impact mixing.” This is not a gentle stirring but “pretty intense, the particles are really hitting each other, rubbing together, hard, sharing ions, reacting in the blender,” he said. This process, called alkali fusion, does not require heat, but it needs a lot of friction

Reinventing the world’s favorite building material