FlyAshDirect has partnered with BASF to develop a chemical solution to beneficiate fly ashes used in concrete
that have been exposed to Powder Activated Carbon (PAC), a material widely
accepted as a method to control mercury emissions at coal burning power plants.
PAC injection systems, when installed prior to the power
plants' particulate control device, will deposit activated carbon onto the fly
ash as it travels through the flue gas, subsequently elevating the level of
carbon or Loss on Ignition (LOI) in the fly ash byproduct. Powder Activated Carbons, which can be up to a thousand times more absorptive than Natural
Carbon, will absorb air entraining admixtures when used in concrete to provide
freeze thaw durability, rendering the fly ash unusable. Due to ongoing air
pollution legislation, environmental agencies are mandating mercury controls at
hundreds of coal burning power generating stations across the United States and Canada,
which have already negatively impacted the quality of millions of tons of fly ash.
More than 10 million tons of fly ash is beneficially used in concrete as a partial replacement for cement every year in the United States.
FlyAshDirect currently owns and operates CarbonBlocker at five power generating
plants throughout the Ohio Valley region and has successfully treated more than 2
million tons of fly ash for use in ready mix concrete. FlyAshDirect, who holds separate patents
on the injection system and chemistry, originally developed the technology to
address the affects of "Natural or Unburned" carbon, which is caused by
low NOx burners or other inefficient burning conditions in the boiler.
Realizing the benefits of the technology, BASF Construction
Chemicals Division saw an opportunity to assist FlyAshDirect in further
developing the chemistry to address the more aggressive challenge posed by PAC
tainted fly ashes and are now prepared to commercialize the new technology.
CarbonBlocker is specifically designed to provide an efficient method to apply
minute quantities of liquid chemistry to alter the properties of fine powders
in a bulk flow environment. This is a key benefit that FlyAshDirect and BASF
believe can be expanded to other new and unique chemistries for the purpose of
treating a wide array of construction materials such as fly ash, cement and slag, providing
unlimited opportunities.
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