What is fly ash
Fly ash is the fine ash powder produced and collected at coal-fired power plants. When coal is finely ground and injected into burning chambers, it ignites nearly immediately, producing two main types of ash: bottom ash and fly ash. As the names suggest, bottom ash, with its larger and heavier particle sizes, falls to the bottom of the combustion chamber where it's mechanically conveyed, whereas fly ash “flies” up with the exhaust stream. This is where it's filtered out and collected prior to the exhaust being released to the atmosphere. It is this fly ash that develops cementitious properties when mixed with cement and water, making it the ideal supplementary cementing material (SCM) for numerous concrete and cement type applications.