“Recent New Source MACT Determinations and Air Quality Compliance Experience in the Iron Foundry Industry”
“Recent New Source MACT Determinations and Air Quality Compliance Experience in the Iron Foundry Industry”
ABSTRACT
Construction and operation air quality permits recently issued to
iron foundries reflect current air quality compliance issues facing the
foundry industry. These issues include the determination of Best
Available Control Technology or BACT under the Prevention of
Significant
Deterioration requirements for major source expansions; emission
control
strategies for hazardous air pollutants released during the pouring and
shakeout of castings, and the establishment of Maximum Available
Control
Technology or MACT for air toxics regulated under Title III of the 1990
Clean Air Act Amendments. Recent construction permits for iron
foundries
in Wisconsin, Indiana and Tennessee have established BACT for the
emissions
of PM10, SO2, NOx, VOC, CO, Pb and Be, and new source MACT for
inorganic
and organic air toxics such as arsenic, chromium, cadmium, benzene and
formaldehyde. Approved operations include continuous casting
production
lines with pouring, shakeout and sand handling operations, iron melting
cupolas, and sand core manufacturing operations. BACT for PM10
continues
to be the use of pulse jet fabric filter baghouses achieving outlet
concentrations
of 0.005 grains per actual cubic foot. BACT for VOC and CO
emissions
has required the use of incineration for cupola operations, and packed
bed scrubbing systems for coldbox core making operations. New
source
MACT for air toxics has been determined to be the same as BACT with no
additional requirements specific beyond that required for criteria
pollutants.
MACT for inorganic air toxics such as trace metals has been established
as the same control methods required for PM10. MACT for organic
air
toxics such as formaldehyde and benzene has been established as the
same
control methods required for VOC. BACT and MACT control methods
and
emission limitations for these pollutants are summarized. Other
foundry
projects which have not been subject to the BACT and MACT requirements
may also affect future control requirements. For example, two
Georgia
foundries will use thermal incineration for the control of VOC
emissions
from their pouring operations. As part of the Wisconsin hazardous
air pollutant control program, state foundries must implement a
pollution
prevention program aimed at a reduction of benzene and other organic
emissions
from pouring, mold cooling and shakeout operations.