Coal ash recycling reaches record rate as production, use patterns shift

Sources: American Coal Ash Association, Farmington Hills, Mich.; CP Staff

Sixty-four percent of the coal ash produced during 2017 was recycled, establishing a new record rate and marking the third consecutive year that more than half of such material produced in the United States was beneficially used rather than disposed.

“The trend for coal ash beneficial use continues to be very positive,” says American Coal Ash Association Executive Director Thomas Adams. “For the fourth straight year, we have seen significant improvement in the beneficial use rate. We look forward to continuing to grow these practices that conserve natural resources, make products that are more durable, and dramatically reduce the need for landfills.”

According to ACAA’s just-released “Production and Use Survey,” 71.8 million tons of coal combustion products (CCP) were beneficially used in 2017 out of 111.3 million tons generated. The rate of ash utilization increased from 56 percent to 64.4 percent year-over-year, and the total volume of material utilized increased by 11.6 million tons. Coal ash production volume increased 4 percent from 2016 levels. ACAA compiles coal combustion byproduct data by directly surveying electric utilities and utilizing additional U.S. Energy Information Administration figures. Key 2017 CCP production and use figures and trends include:

  • Use of coal fly ash in concrete remained approximately level with the prior year at 14.1 million tons. Concrete producers and consumers indicated a desire to use more fly ash, but several regional markets were affected by shifting supply dynamics associated with coal-fueled power plant closures. 
  • Utilization of a key “non-ash” coal combustion product increased significantly. Synthetic gypsum is a byproduct of flue gas desulphurization units, also known as “scrubbers,” located at coal-fueled power plants. Use of synthetic gypsum in panel products (i.e. wallboard) increased 60 percent to 15.9 million tons in 2017. The spike is attributed to lower than usual synthetic gypsum shipments reported in the prior year and growth in wallboard production.
  • Synthetic gypsum use in agricultural applications—where the material improves soil conditions and prevents harmful runoff of fertilizers—also increased 50 percent to 1.2 million tons. Part of this growth is attributed to a large new synthetic gypsum source entering the market.
  • Use of CCP in pond closure activities increased dramatically from 435,000 tons in 2016 to 4.5 million tons in 2017 as utilities ramped up compliance with environmental regulations that effectively require an end to the practice of wet disposal. Fly ash, bottom ash, and synthetic gypsum were all used in construction of new permanent disposal facilities.

“As America’s electricity grid changes, the coal ash beneficial use industry is evolving as well,” Adams observes. “As we work diligently to utilize the 36 percent of coal combustion products that are still disposed annually, our industry is also taking significant strides in developing strategies for improving the quality and availability of these materials.”

Increasing beneficial use requires ash marketers to ensure that products are consistent and available when customers need them, he adds, requiring large investments in technology and logistics. Additionally, the coal ash beneficial use industry is actively deploying technologies and strategies for harvesting raw feeds that were previously disposed.