The West Virginia Department of Environmental Protection is taking comment until July 28 on a draft air permit that would allow Virginia Electric and Power to install and operate a process for separating the fly ash generated at the Mt. Storm Power Station in Grant County.
This process would be constructed, owned, and operated by a third-party, Separation Technologies LLC (ST), on the Mt. Storm property. The project would separate high-carbon fly ash from low-carbon fly ash. The mineral content ash will be used as a supplementary cementitious product for ready mix concrete. The high-carbon fly ash may be returned to the boilers as fuel (which will off-set the use of some virgin coal and subsequently create a higher mineral content ash that can be recovered through the separation process) or it may continue to be trucked to a landfill.
Capturing and beneficially reusing both the mineral and high-carbon content ash has the benefit of minimizing the amount of fly ash that will need to be landfilled. Currently, all of the ash generated by Mt. Storm is landfilled, the DEP said.
This project will not affect the generation or disposal of bottom ash. Initially, a single separator will be installed to process ash from Units 1 and 2, which will utilize approximately half of the plant total fly ash production. Subsequently a second separator will be installed, increasing the capacity to process all of the fly ash produced from Units 1, 2 and 3.
The Mt. Storm Power Station is a coal-fired facility that generates ash and other byproducts (such as gypsum) from its operation. Most of these byproducts are currently placed in an on-site landfill that was designed for this purpose.
There are two widely available methods of generating low-carbon ash for the cement market; either processing the ash in a separate circulating fluidized bed boiler which leaves only low-carbon ash, or physically separating the high-carbon ash from the low-carbon ash. The project that is the subject of this application is a physical separation process.
Separation Technologies LLC’s proprietary technology consists of a unique, triboelectrostatic belt separator. Fly ash that is collected in the main boilers electrostatic precipitators (ESPs) at Mt. Storm is placed into silos at the facility. From there, it will be fed into the separation process, which is a belt conveyor with a thin gap between two parallel planar electrodes. The ST separator utilizes electrical charge differences between materials to separate the fly ash into two products. The separator produces a 3% “loss on ignition” (LOI) low-carbon mineral product, which is sold as a supplementary cementitious material for use in concrete, and a high-carbon ash product. For the Mt. Storm facility, the high-carbon ash product will be returned to the utility for re-burning.
Virginia Electric and Power is a subsidiary of Dominion Resources (NYSE: D).
Mt. Storm is the largest coal-fired power station managed by Dominion. Its three units can generate nearly 1,600 MW. The station is located on Mount Storm Lake in the Allegheny Mountains of northeastern West Virginia.