Introduction

Through well-known industry expertise and relationships, Birchtech has worked closely with a major coal-fired power utility located in the Mid-Atlantic region, supporting multiple plant locations to holistically provide differing technology solutions to address varying types of water and removal of multiple critical contaminants from different water streams.

Challenges and Regulatory Context

Challenges at this large utility that affected two plant locations involved multiple water touch points, from its filtration system that cleans water prior to entry into the boiler and hydrogen sulfide (H₂S) on the boiler water walls, which can cause significant corrosion leading to boiler failure. Additionally, this utility uses a wet scrubber for mercury emissions removal.  A wet scrubber control device, used by certain coal-fired power plants, municipal waste incinerators, and other applications, collects mercury and other pollutants through an adsorption process by the liquid in the scrubber.  The contaminated scrubber liquid must be properly treated to remove certain pollutants prior to disposal.  Wet scrubbers at coal-fired power plants are heavily contaminated with boron and selenium, a regulated contaminant under the U.S. EPA’s Safe Drinking Water Act (SDWA).  The EPA also governs wastewater with strict pollution controls, prohibiting disposing of toxic heavy metals, such as selenium, into local waterways.  

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With stricter environmental regulations, the extensive cost of removing certain heavy contaminants is a significant driver¹ of early closures for coal-fired power plants. On March 12, 2025, the EPA announced that it would reconsider certain water pollution limits for coal power plants to allow a longer life for these utilities. However, as power demands on the grid continue to increase, the only true solution to ensuring clean “energy dominance” in the U.S. is more affordable and effective treatment solutions.

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Birchtech’s Integrated Solution

With numerous treatment concerns affecting water going into and out of the system’s boiler, the utility’s environmental leadership approved a holistic approach from Birchtech which focused on improved efficiency and affordability.

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To initiate the project, the utility’s water was analyzed from four different sources to fully assess the level of contaminants at each source.

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The first project at this utility addresses the filtration system that included a thorough inspection and validation of the utility’s equipment to determine an effective solution that would provide upstream protection of the plant’s reverse osmosis for its incoming boiler feed water. Media was assessed and a combination of sand and anthracite was selected based on performance and cost.

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Contaminant Treatment: Boron and Selenium

The utility was aware that the wet scrubber control device was contaminated with both boron and selenium. The analysis of the wastewater detected high levels of each contaminant. To remove boron, a naturally occurring element found in U.S. coal that can be toxic to plants, animals, and humans, from the utility’s scrubber wastewater, a combination of anion and cation.

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Exchange resins were selected for the effectiveness with this contaminant. Birchtech’s turnkey changeout service includes with the removal of the old media and installation of the new resins. Due to extensive nature of this contaminant and to ensure that the utility’s power generation schedule was not interrupted, the resin change out service will begin early 2026.

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Wet scrubber water from coal-fired stacks is often contaminated with selenium, as was the case with this utility. The selenium must be removed prior to disposing of scrubber water into wastewater bed/stream. Resins are the most common approach to remove selenium in this application. These resins are referred to as “bacteria” or “bugs”, as they operate anaerobically to “eat” the selenium. However, optimal conditions, which are difficult to control, are necessary for this solution, which is costly and labor intensive.

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From expertise in a variety of utility conditions and contaminant removal technologies, Birchtech coordinated and managed a pilot test, to determine the effectiveness of a proprietary adsorptive media, a novel approach for the removal of the selenium.

Through a data-driven approach coupled with Birchtech’s strong industry knowledge, expertise, and partnerships, it is estimated that this utility received a total cost savings of several hundred thousand dollars (relative to existing technologies) for these combined treatment technologies as Birchtech’s integration services for water treatment solutions are expected to provide utilities with an average cost improvement of 30%² compared to other solution providers.

Commitment to Sustainability

Birchtech is committed to providing more affordable, sustainable, and highly effective environmental technologies focused on the removal of heavy contaminants from our air and water.

Learn more about Birchtech’s environmental technology integration services for water treatment solutions here:https://www.birchtech.com/water-treatment.

Contact sales@birchtech.com to discuss a custom treatment solution for your utility’s contaminant requirements.

1. Statement made from Birchtech’s industry knowledge. Also see: Friedman, L., & Davenport, C. (2024, April 25). EPA Severely Limits Pollution from Coal-Burning Power Plants. The New York Times. https://www.nytimes.com/2024/04/25/climate/biden-power-plants-pollution.html

2. Average plant cost improvement based on internal calculations and comparisons of current industry product supply pricing.