Fly ash, by definition, is mineral impurities fused together during the burning of coal in electric power generation plants. These impurities are often suspended minerals such as feldspar, shale, quartz, and types of clay. Once fused, they float to the top of the furnace. Generally, electrostatic precipitators filter out the fly ash.
When collected, fly ash looks similar in appearance to Portland cement. However, the two materials are chemically different. Because the makeup of fly ash can vary, its inherent cementitious properties may be different from one batch to the other. Two of the more commonly seen fly ash varieties are Class C and Class F, both of which are used to make concrete.
Fly ash has many end-uses, and not just in concrete. This is unsurprising considering that the US alone produces 100 million tons of fly ash annually. As such, we have found a vast variety of uses for this material.
As previously stated, fly ash with desirable properties is used to make concrete. In fact, over 50% of the concrete laid in the US contains fly ash. Its cementitious properties make it an ideal material to create industrial concrete. In fact, fly ash makes it possible for mixes to be made with time delay hardening and other desirable attributes.
Grout And Cement
Of course, fly ash is also used to create cements and grouts. These are used to lay tile, add finishes to the sides of sinks and tubs, and other uses in masonry.
A way for bricks to be made from fly ash has been created which uses 85% less energy than traditional brick making. Bricks made from fly ash are cured via steam, as opposed to traditional bricks, which must be fired in a kiln. Plus, the production of fly ash bricks emits 82% less CO2 than traditional as well.
Classes of fly ash, which lack the properties of the C and F classes, are used as mineral fillers. These fillers come into play when the need to stabilize soft soil arises, or during construction.
Finally, fly ash is often used to stabilize and solidify sewage waste. Its alkalinity and water absorption aids in the treatment of raw sewage, turning it into fertilizer and raw bio-fuel.
Fly ash is never too far from home, as it can also be found in common everyday items such as counter tops, toothpaste, bowling balls, utensils, window frames, floor and ceiling tiles, and more. If you would like to learn more about fly ash and its uses and transportation, we invite you to contact us.