The Potential of Fly Ash: Meeting Demand Through Ash Harvesting and Beneficiation

With the decreasing reliance on coal-fired power plants and the shift towards natural gas and renewable energy, the source of פליען אַש is transforming dramatically.

איצט, the industry is witnessing a move fromfresh” אַש, produced directly from active coal power plants to harvested ash—material that has previously been stored in landfills or ash ponds. In the US alone, over a billion tons of fly ash are in these impoundments, many of which pose risks of groundwater contamination, particularly in light of April’s Environmental Protection Agency (EPA) rulings on coal ash management practices. Given this, we need to employ the best fly ash separation equipment to recover, harvest, and beneficiate fly ash before it is suitable for use.

זינט 2008, ו.ס. coal fly ash production has seen a notable decline—from a high of 72.5 million short tons to merely 36.2 million short tons in 2018, according to the אמעריקאנער קוילן אַש אַססאָסיאַטיאָן (אַקאַאַ). Despite this drop in production, demand within the concrete industry for fly ash has surged. אין 2018, beneficial use in concrete made up 12.5 million short tons, 60% of total fly ash utilization. With projections indicating a potential increase in fly ash utilization to 90% by 2039, yet a continual decline in production—estimated at 32 million short tons by the same year—this creates a significant gap between supply and demand.

The burgeoning construction sector, driven by the 2021 $1 trillion infrastructure bill approved by the Senate, helped increase this demand. אָבער, as we transition to harvested fly ash, we must focus on ensuring that this material meets the specifications for high-quality concrete production.

How Fly Ash Harvesting Helps

  • Harvesting fly ash from impoundments prevents groundwater contamination
  • Recovering fly ash from historic landfills helps prevent future pond or dam failures in sensitive areas
  • Reclaims landfill space
  • Meets the rising construction industry demand
  • Cheaper than raw materials; lowers logistics costs
  • Generates a low CO2 supplementary cementitious material, lowering the emissions footprint of the construction sector.
  • Sustainable, combustion-free process

The Process of Ash Harvesting and Beneficiation

Fly ash uses can generally be classified into two categories:

  1. Ready To Use Ash (Unprocessed Ash): Some unprocessed ash in landfills meets the American Society of Testing and Materials (ASTM) C-618 and other regulatory specifications. This ash can be excavated and directly sold for beneficial use.
  2. Beneficiated Ash (Processed Ash): אָבער, certain ash may not meet the necessary specifications due to various factors, such as high loss on ignition (געזעץ), moisture content, or chemical composition. This ash requires processing or beneficiation in advanced fly ash separation technologies to improve its viability for concrete production.

ST Fly Ash Separation Technology

To address these challenges, סטריט עקוויפּמענט & Technology employs the STET סעפּאַראַטאָר. This innovative technology sports a parallel plate electrostatic separation mechanism featuring horizontally oriented electrode plates that enable advanced tribo-charging and conveying of particles via a high-speed open mesh conveyor belt.

This design allows for a much higher processing rate and the capability to handle finer powders than typical electrostatic devices. Since its commercial deployment in 1995, the STET separator has been successfully applied to separate unburned carbon from fly ash minerals, improving the value of fly ash for concrete production. With processing capacities of up to 40-45 טאָנס פּער שעה, the STET separator integrates seamlessly into existing workflows, providing adjustable control over product quality with user-friendly automation options.

As coal use continues to decline, recovering and improving fly ash will become the norm, helping the industry flourish while supporting environmental sustainability. Utilities and producers embracing this trend can expect concrete that meets high-performance standards, lowers emissions, and manages resources in the most sustainable way. By combining fly ash separation technologies with sustainable practices, the future of fly ash looks promising.

Looking for fly ash separation equipment? Call ST Equipment & Technology LLC at (781) 972-2300 to learn more.