“Ash can be used to replace up to 30% of cement,” Krish Mehta, co-founder and CEO of PHNX Materials, told TechCrunch. By displacing cement in concrete, fly ash from coal plants can eliminate a ...

One of them is eco-friendly. It uses industrial waste, including fly ash and calcium carbide sludge, with novel geometrically shaped blocks that make the building seismically resistant.