Testing Of Accelerated Pozzolanic Activity Of Fly Ash,
2026
UK CAER
Testing Of Accelerated Pozzolanic Activity Of Fly Ash, Anne Oberlink, Tom Robl, Bob Jewell, Haley Johnson
World of Coal Ash Proceedings
The determination of the pozzolanic reaction in fly ash by ASTM strength activity index has been shown to be problematic, frequently producing false positives. The use of Wenner probe resistivity has been demonstrated to be rapid, simple and non-destructive method, producing no false positives. However, using this method and confirming it with other techniques finds that the reaction itself is slow with a dilatancy of 28 days or more before the measurements become discriminatory, a major drawback to this method. This study used high-temperature, high humidity curing of OPC-based mortars with various fly ash sources to determine how pozzolanic activity …
Innovative Analysis Of Groundwater Data For Scalable, Defensible, And Predictive Compliance,
2026
Life Cycle Geo, LLC
Innovative Analysis Of Groundwater Data For Scalable, Defensible, And Predictive Compliance, Shannon Zahuranec
World of Coal Ash Proceedings
Groundwater monitoring networks at coal combustion residual (CCR) facilities now yield dataset volumes that routinely exceed the capacity of traditional, univariate interpretation. This presentation introduces a scalable multivariate and machine learning (ML) framework that prioritizes understanding data structure before predictive models are applied. The workflow applies Principal Component Analysis and other multivariate statistics to groundwater datasets, to illustrate how unsupervised learning can rapidly reveal dominant sources and controls on impacted and unimpacted groundwater quality. The talk frames multivariate analysis as a practical portfolio management tool, emphasizing inference categories rather than concentrations or site identifiers. Fleet-scale multivariate screening offers strategic advantages …
Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods,
2026
Tennessee Valley Authority
Subsurface Delineation Of Coal Combustion Residuals Using Multiple Geophysical Methods, Eric Hageman, Adam Rak, Thomas Jordan, Kate Mckinley
World of Coal Ash Proceedings
Geophysical techniques provide alternative methods of Coal Combustion Residual (CCR) delineation and characterization to supplement more invasive boring programs used for beneficial reuse planning. A demonstration project was designed to characterize the electromagnetic and seismic stratigraphy of CCR material and test the effectiveness of three geophysical techniques: Electrical Resistivity Imaging (ERI), Transient Electromagnetic (TEM) induction, and Multi-channel Analysis of Surface Wave (MASW). The demonstration project was completed at a dry-stack CCR unit containing a variety of CCR ash, gypsum, and thin layers of drainage aggregate (limestone). During a single-day deployment, several geophysical survey tests were conducted in specific areas of …
Benefits Of Geophysical Imaging For Coal Combustion Residuals Management Unit Delineation,
2026
Arcadis
Benefits Of Geophysical Imaging For Coal Combustion Residuals Management Unit Delineation, Gabriel Herbert
World of Coal Ash Proceedings
Gabriel J. Hebert1, Gregory B. Byer1, Margaret Gentile1 1Arcadis U.S., Inc., 2839 Paces Ferry Road SE, Suite 1000, Atlanta, GA 30339 KEYWORDS: geophysical imaging, delineation, CCRMU ABSTRACT Under the 2024 Legacy CCR Rule detailed in 40 CFR Part 257, Section 75, all electric utility companies with a known legacy coal combustion residuals (CCR) surface impoundment are required to conduct a facility evaluation to identify the location, dimensions, and volumes of CCR placed and remaining on site and to assess structural stability. At a minimum, the presence or absence of CCR management units (CCRMUs) must be documented through a desktop records …
Evaluating The Properties Of Ohio Ponded Fly Ash For Reliable Use In Concrete Mixtures,
2026
The Ohio State University
Evaluating The Properties Of Ohio Ponded Fly Ash For Reliable Use In Concrete Mixtures, Ayah Suliman
World of Coal Ash Proceedings
Concrete producers are under pressure to reduce the carbon footprint of concrete while maintaining a reliable supply of supplementary cementitious materials. Meanwhile, U.S. coal production in 2023 declined to less than half of its 2008 peak, significantly reducing the availability of fresh ASTM C618 compliant fly ash. At the same time Ohio contains more than 145 million cubic yards of coal combustion residuals stored in ponds, representing a large and underutilized source of potential fly ash for concrete applications. This study evaluates the suitability of harvested Ohio ponded fly ash for use in concrete through practical and specification-driven testing aligned …
Basin Ash Harvesting At The Brunner Island Station,
2026
ST Equipment & Technology
Basin Ash Harvesting At The Brunner Island Station, Kyle Flynn
World of Coal Ash Proceedings
Tribo-electrostatic separation has been used for the commercial beneficiation of coal combustion fly ash to produce a low carbon product for use as a cement replacement in concrete for over twenty-five years. With 24 separators in 18 coal-fired power plants and cement plants across the world, ST Equipment & Technology LLC’s (STET) patented electrostatic separator has been used to produce over 25 million tons of low carbon product that has been recycled for use in concrete or cement production. STET has developed and commercialized a new process for beneficiation of reclaimed fly ash from landfills and ponds that utilizes fly …
Extracting Rees From Refuse Pile Coal,
2026
Concurrent Technologies Corporation (CTC)
Extracting Rees From Refuse Pile Coal, Howard Mcclintic
World of Coal Ash Proceedings
Concurrent Technologies Corporation (CTC) has a patented high temperature electric arc furnace (EAF) technology that reaches 4000-degree centigrade temperature(s). Such high temperatures are sufficient to extract each of the seventeen rare earth elements (REEs) from coal fly ash to ultimately manufacture diverse magnets. Neodymium iron boron magnets (NdFeB) are the strongest magnets produced, heretofore almost exclusively by the Chinese. For national security reasons, CTC has become part of the domestic supply chain, as an alternate to China. Scaling is the next hurdle, since our demonstration unit is operational. Nationwide, coal is decreasingly used as a fuel for generating electricity. However, …
Adaptive Design And Execution In Ccr Pond Closure: A Case Study Of Technical And Regulatory Innovation,
2026
AECOM
Adaptive Design And Execution In Ccr Pond Closure: A Case Study Of Technical And Regulatory Innovation, Jay Mokotoff, Angie Casbon-Scheller
World of Coal Ash Proceedings
Closure by removal (CbR) of CCR impoundments presents complex challenges, particularly when unique hydrogeologic conditions exist. This presentation highlights the advance planning and ongoing closure of a Midwestern utility’s East Ash Pond (EAP), a relatively small facility with highly atypical characteristics. To comply with the CCR Rule, sluicing to the EAP ceased while the generating unit remained operational. Fly ash handling was converted to a dry system for beneficial reuse; however, wet sluicing of bottom ash continued. To avoid constructing a new regulated CCR impoundment, an innovative geotextile tube containment area (GTCA) was designed and implemented to capture bottom ash …
Evolution Of Instrumentation Use For Ccr Unit Decision Making,
2026
Tennessee Valley Authority
Evolution Of Instrumentation Use For Ccr Unit Decision Making, Nick Mcclung, Victoria Bierwirth, Matt Bishop
World of Coal Ash Proceedings
Over the past decades, the power industry’s instrumentation needs and requirements have shifted to meet industry standards and regulations. In the early 2010s, piezometers and slope inclinometers were the primary types of instrumentation used to evaluate the stability of a CCR Unit. Some of the piezometers and slope inclinometers installed are still in use today to evaluate long-term stability for operations and closure. Since this time, additional instrument types were selected for installation including observation wells and temporary wells to further understand phreatic conditions within the CCR Unit. As utilities are faced with closures including removal of free liquids, data …
Coal Ash-Derived Aluminosilicate Precursors: A Chemical Engineering Approach To Geopolymer Characterization,
2026
University of Louisiana at Lafayette
Coal Ash-Derived Aluminosilicate Precursors: A Chemical Engineering Approach To Geopolymer Characterization, Hafiz Abdul Basit, Abdullah Bashir, Abdur Raafey
World of Coal Ash Proceedings
The chemical and microstructural evaluation of coal-derived aluminosilicate precursors is critical for understanding their suitability in advanced construction material systems. In this study, a characterization of Class F fly ash, ground granulated blast furnace slag (GGBFS), and Silica Fumes (SF) was conducted to elucidate their morphological and elemental features. Scanning Electron Microscopy (SEM) was used to assess particle morphology and surface characteristics (porosity, particle diameter, particle geometry), and Energy-Dispersive X-ray Spectroscopy (EDS) to determine elemental composition and distribution. The analysis revealed distinct morphological and compositional differences among the precursors, including spherical fly ash particles, calcium-rich slag phases, and ultra-fine silica …
State Permitting Program Update,
2026
Barnes & Thornburg LLP
State Permitting Program Update, Jessica Reiss
World of Coal Ash Proceedings
State Permitting Program Update Jessica L. Reiss, Barnes & Thornburg LLP, 11 South Meridian Street, Indianapolis, IN 46204 KEYWORDS: states, permitting, permit program, rulemaking ABSTRACT At the end of 2016, the United States Congress authorized states to establish permit programs for coal combustion residuals (CCR) surface impoundments and landfills.[1] Since then, several states have established such programs, and the United States Environmental Protection Agency (U.S. EPA) has approved programs for Oklahoma,[2] Georgia,[3] Texas,[4] and North Dakota,[5] proposed approval for Wyoming,[6] and denied approval for Alabama.[7] Other states, such as Indiana,[8] are actively working through the state rulemaking process and plan …
Zero-Waste And High-Value Valorization Of Coal Combustion Residues Via Critical Minerals Recovery And Cementitious Materials Production,
2026
Missouri University of Science and Technology
Zero-Waste And High-Value Valorization Of Coal Combustion Residues Via Critical Minerals Recovery And Cementitious Materials Production, Hongyan Ma
World of Coal Ash Proceedings
Coal combustion residues (CCRs) pose significant environmental and disposal challenges, yet they also represent an untapped resource rich in aluminosilicates and critical minerals. This work presents a zero-waste, high-value valorization pathway that integrates critical mineral recovery with the production of cementitious materials. Advanced separation and extraction techniques are employed to recover strategically important elements such as gallium and rare earths, while the mineral-rich residues are simultaneously processed into supplementary cementitious materials (SCMs) for blended cements and concretes. This integrated approach not only offsets the environmental burden of CCR disposal but also supports domestic supply chains of critical minerals and reduces …
Revolutionizing Closure Systems: The Performance Advantages Of Structured Geomembranes,
2026
AGRU America
Revolutionizing Closure Systems: The Performance Advantages Of Structured Geomembranes, Scott Perugia
World of Coal Ash Proceedings
Coal combustion residual (CCR) containment facilities have traditionally been closed using methods that have changed little over several decades, but structured geomembranes are now reshaping closure design by improving slope stability, increasing interface friction, enhancing drainage, and providing long-term durability. Two systems are emerging as leading solutions: a structured geomembrane paired with a geotextile and vegetative cover, and a structured geomembrane paired with engineered turf. This presentation compares these approaches using field performance data, laboratory testing, and lessons learned, with emphasis on key factors such as infiltration control, drainage efficiency, slope stability, constructability, and regulatory compliance. The engineered turf system …
Developing Concentrated Brines / Salt Slurries For Disposal Of Coal Ash Wastewaters.,
2026
Xylem
Developing Concentrated Brines / Salt Slurries For Disposal Of Coal Ash Wastewaters., Lance Edling
World of Coal Ash Proceedings
If coal ash wastewater is not fully concentrated to the greatest extent possible, then this results in greater disposal volumes and costs. However, concentrating a wastewater stream high in scaling compounds can be difficult. Membranes are prone to scale and Vacom thermal systems are higher in operating cost. This presentation will discuss the need to minimize disposal volumes by concentrating wastewater that is readily prone to scale and foul. The discussion will present past project examples of waste streams that were concentrated until salt crystals formed and the method used to minimize fouling and scaling during the concentration process. In …
Recinis™ Wet Beneficiation Process For Landfilled Coal Ash,
2026
ReVanTEC Solutions
Recinis™ Wet Beneficiation Process For Landfilled Coal Ash, Tim Sambrook
World of Coal Ash Proceedings
The decline of coal-fired power generation has reduced fresh “Run-of-Station” ash availability, increasing reliance on reclaimed ash from landfills to meet supplementary cementitious material (SCM) demand. This shift has lowered OPC replacement rates and raised concrete costs due to inconsistent ash quality. ReCinis™ offers a low-capex wet beneficiation solution for landfill-aged, saturated, and variable-quality coal ash. With over 5 billion tons of ash impounded in the U.S., this process enables long-term supply security where dry beneficiation is unsuitable. Combining proven mineral processing techniques with coal ash expertise, ReCinis™ can be deployed as a 150,000 tpa skid-mounted plant or scaled to …
Lessons Learned From A Full-Scale Discrete In-Situ Stabilization Project For Ccr Impoundment Closure,
2026
ENTACT, LLC
Lessons Learned From A Full-Scale Discrete In-Situ Stabilization Project For Ccr Impoundment Closure, Tony Moran, Paul Jennings, Jacob Susser, Tim Silar
World of Coal Ash Proceedings
ENTACT, in collaboration with Silar Services, Inc., the patent holder of Discrete In-Situ Solidification (DISS) technology, has successfully performed a full-scale implementation of DISS in a Coal Combustion Residual (CCR) impoundment. DISS hydraulically isolates ash from surrounding groundwater by constructing a low-permeability barrier at the impoundment bottom to treat a layer of ash and tying into underlying natural soil layers. DISS enables targeted stabilization within a designated treatment zone, minimizing the disturbance of overburden compared to traditional excavation methods and reducing the use of costly cementitious reagents. The process starts with Reagentless Drilling of the overburden CCR utilizing a specialized …
From Clogs To Compliance: Overcoming Persistent Leachate Head Issues In Ccr Landfills,
2026
TRC
From Clogs To Compliance: Overcoming Persistent Leachate Head Issues In Ccr Landfills, Breanne Kahnk, Zachary Bauman
World of Coal Ash Proceedings
State and federal regulations require that landfills, including coal combustion residual (CCR) landfills, be designed and operated to maintain leachate head levels of less than 30 centimeters (approximately 1 foot). While proper leachate collection system design and routine maintenance are critical for meeting this requirement, challenges such as clogging of drainage media, pipes, fittings and/or pipeline perforations, settlement of collection pipes, and breaks in the piping system can lead to elevated leachate levels, posing risks to compliance and long-term system performance. TRC will provide an overview of leachate collection system regulatory requirements along with design, operation, and maintenance strategies that …
Plasma Coal Ash Processing For Enhanced Recovery Of Rare Earth Elements & Precious Metals: Proven From R&D To Commercial Plants,
2026
Plasma System LLC USA
Plasma Coal Ash Processing For Enhanced Recovery Of Rare Earth Elements & Precious Metals: Proven From R&D To Commercial Plants, George Paskalov, Victoria Campbell, Jason Honigberg
World of Coal Ash Proceedings
Our Radio-frequency Plasma System is an ash pretreatment before the application of extractive metallurgy and addresses current elemental, methodological, and technological limitations of complex and refractory coal ash. Our system data shows from 10-20% improved recovery, to 9x-100x. RFP can access all metals contained in coal ash. Our focus is not on the alteration of established methodologies, such as cyanidation for non-refractory ore, which has a proven return and capacity to achieve target revenue at-scale. Using the RFP systems, no waste is created, overburden can be more easily dealt with, and no metal content will be left behind. We assert …
Probing The Critical Element Chemistry Of Coal-Combustion Fly Ash: Electron Microbeam Investigations Of The Spent Ash From The Pilot-Scale Acid Extraction Of Rare Earth Elements From A Beneficiated Kentucky Fly Ash, James Hower
World of Coal Ash Proceedings
Fly ash derived from the combustion of an eastern Kentucky high volatile bituminous coal blend was beneficiated to yield a <75-μm product with a reduction in the carbon and spinels and reacted with a strong acid in a pilot-scale unit to extract rare earth elements. Electron microscopy showed a wide range of rare earth-bearing minerals. The acid-extracted fly ash had a rim that was depleted in REE and in most other elements except silicon.
Standardization Of Coal Ash Testing, Classification, And Harvesting,
2026
EPRI
Standardization Of Coal Ash Testing, Classification, And Harvesting, Benjamin Gallagher, Chris Frishcosy, Eric Hageman
World of Coal Ash Proceedings
Standards such as product specifications, test methods, practices and guides play a crucial role in supporting both commerce and science. Standardization helps build consistency and reliability whether it pertains to the performance of an ingredient in a product or in the measurement of a material characteristic. Coal combustion products, such as coal ash and synthetic gypsum, exhibit unique characteristics and many standard have been developed to characterize these materials and support their beneficial use. ASTM is a voluntary, consensus-based organization, and publishes many standards related to coal combustion products. Currently, there are seven ASTM standards related to chemical analysis of …
