Recycling Fly Ash Into Concrete

Dairyland continuously pursues opportunities to re-use and recycle materials in every area of operations. That includes the coal ash from our power plants. For each ton of coal Dairyland power plants burn to produce electricity, approximately 5 percent, or 100 pounds, results in an ash byproduct.

Eighty percent of the total is fly ash, a light powdery substance that is collected in electrostatic precipitators. Dairyland markets the ash to be recycled as an additive compound in ready-mix concrete, since the major components in cement (the active ingredient in concrete) are the same as those in fly ash.

Most concrete today in our area is 30% fly ash, contributing to stronger, less permeable concrete-at a lower price. Since fly ash is less than half the price of Portland cement, consumers save money when building roads, bridges, buildings and other community projects with concrete that contains fly ash.

In 2005, 85 percent of the fly ash was recycled.

Dairyland also markets about 60 percent of our bottom ash, the remaining 20 percent of ash byproduct, which is recycled as a substitute for crushed rock or sand in road construction and as an anti-skid material in lieu of sand or salt on winter roads.