Microclimates allow application of coatings Merrimack Station, a
power plant in Bow, N.H., owned and operated by Public Service
of New Hampshire (PSNH), burns 4,000 tons of coal a day, as it
generates enough power to satisfy the energy needs of one-third
of New Hampshire's population. The fly ash produced during the
combustion of coal contains a trace amount of mercury that is
emitted into the atmosphere. The plant's operators sought to
reduce these emissions to improve the environment and public
health, and to meet strict air-quality legislation recently
passed in New Hampshire. PSNH executives chose to install a wet,
limestone-based flue-gas-desulphurization (FGD) system to limit
mercury and sulfur dioxide emissions. Chicago Bridge & Iron
Company (CBI) built the primary processing system for the FGD
system. It included six carbon-steel tanks located side-by-side.
The tanks range from 24 ft to 56 ft in diameter. Once
constructed, the interior of the tanks required a special
coating to ensure protection again