On Site Mercury Remediation via Activated Fly Ash

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DESCRIPTION (provided by applicant): Coal-fired power plants and burners are vital drivers of the U.S. economy-but they unfortunately produce substantial amounts of mercury (Hg) that are seriously harmful to human health, particularly linked to damages of the nervous system. Healthcare costs due to Hg exposure are estimated to be in the billions of dollars annually. New mercury-emission regulations (effective 2015) set a strict Hg cap of 1.3x10-2lb/GWh for existing electrical generating units (EGUs), which represents a challenge for the power-generation industry since 40% of today's units do not have adequate mercury pollution control equipment. The most reliable and widely utilized solution for mercury capture from power plants is exhaustive activated carbon injection (ACI), for which sorbent recurring costs are at least $5,000 per pound of Hg removed. The development of a new, cost-effective Hg-capture technology is crucial to mitigate human health risks and associated national healthcare costs, and to control industry/consumer costs under the upcoming regulations. Our preliminary work has produced a material that could replace the currently used injectable activated-carbon sorbents. The new material is more effective/efficient and potentially less expensive. Current mercury capture technologies have limitations that are largely due to physical sorption and do not address core problems of permanent mercury capture. We propose a technology that overcomes these limitations with materials that chemically bind mercury and offer the flexibility of safe disposal. The overall goal of this multi-phase SBIR project is to develop, prototype, and commercialize a proprietary gaseous pollutant capture technology that can be retrofitted to existing coal-fired facilities and incorporated into new ones. The on-demand Hg-capture technology is based on state-of-the-art material-i.e., a reprocessed fly ash byproduct that is reformed into a high-grade Hg oxidizing material via an innovative surface treatment. Our preliminary work has shown that this modified fly ash achieves exceptionally high levels of Hg removal. To fully establish the feasibility of this novel approach, Pollution Control Technologies, LLC (PCTech) will pursue the following Phase I Aims: 1) Demonstrate the feasibility of fly ash activated with pyridinium tribromides for mercury chemisorption; 2) Establish the Hg capture efficiency of the developed PTB activated fly ash on a pilot-scale combustion unit; and 3) Validate Hg disposal through HgBr2 extraction from saturated activated fly ash. Phase I support will allow the PCTech research team to obtain a complete experimental dataset related to production/implementation of fly ash-based material that will permit an accurate cost assessment and will validate the new Hg capture technology. Follow-on Phase II funds will be used to carry out a large-scale mercury capture project at a power plant facility and to complete an economic analysis of the technology. This will set the stage for the development of commercial-grade Hg capture technology and full-scale installations.