Saturn Materials, LLC - A brick company

Acceptable Use of Fly Ash in Concrete

Fly Ash is a waste material produced from burning coal. Fly ash is abundant and often has to be disposed of in landfills or stockpiled. Ideally, this material should be consumed and transformed for another purpose. One option for consumption is to use the material to form concrete. Currently, ASTM International, whom is responsible for issuing and maintaining standardized methods and practices, recognizes fly ash as an acceptable additive in concrete. OSHA has also recognized fly ash use in concrete as a safe choice for the consumption of fly ash.

Fly Ash can come in different forms and compositions based on the coal burning process and the nature of the coal material. Depending on the composition of the fly ash, a chemical reaction will take place within concrete, which irreversibly changes the material into a hardened material capable of withstanding external forces without damage. Two types of fly ash are most commonly used in concrete applications, Class C fly ash and Class F fly ash. Class C contains larger quantities of calcium and is cementitious in nature meaning it will become a solid with the addition of water. Class F fly ash is pozzolanic and must be used in conjunction with a material such as cement in order to harden in the presence of water. For more information on fly ash, visit the American Coal Ash Association.

Since the early 1940s, this material has been used in concrete for various applications. When fly ash is mixed into a concrete matrix, the resulting material has been proven to require less water, have a lower permeability, and prohibit some deleterious chemical reactions. There are many examples of concrete structures and roadways, which have incorporated fly ash to produce high performance concrete. These have shown great success in the field.

Saturn Materials, LLC is using fly ash for an additional application, the formation of masonry products. The company has created a material which incorporates fly ash to produce masonry products with excellent strength and durability. By utilizing their private design, they have created a green product for architectural use. Fly ash does not require processing, which greatly reduces the carbon emissions. Using cement as the alternative, carbon emissions are being expelled into the atmosphere. Additionally, as fly ash is being consumed, it decreases the need for the storage of this waste material. Moreover, this material is readily available and does not require extracting raw materials like in the production of cement. All of these factors combine to increase the attractive green quality of the material for this application.

Saturn Materials, LLC has taken the concept of incorporating fly ash in concrete and managed to produce a reliable, high-volume fly ash mix that will pass ASTM standards for use in masonry applications. The material is green in nature due to its content and manufacturing process. Saturn Materials has carefully designed its state-of-the-art facility to reduce process time and increase productivity, further extending its green proposition.

Jessica Silva, PhD