MDI Emissions Reporting Guidelines for the ... - Polyurethanes

Where:
Therefore:
MDI Emissions Reporting Guidelines for the Polyurethanes Industry
Vair = 50,000 cfm*(273.15K /295.15 K) = 46,273 acfm
ppmv = (0.00000682/760)*(1,000,000) = 0.0090 ppmv
MW = 250.26
Kmdi = 1.0
Ciso = (29,838lbs MDI/725,000 lbs Total feed) = .04
Fmdi = 0.0001
Tso = 8760 hrs/yr
359 = the molar volume of an ideal gas in ft3 /lb-mole @ 0 o
C and 1-atmosphere
60 = time, minutes/hr
L so = (46,273 acfm)*(60 min/hr)*(0.009ppmv/1000000)*(250.26)*(0.04)*(1.0)*(8760)*(0.0001)
L so = 6.12 x 10 -4 lbs/yr
Total Emissions = L cb + L mp + L so
Total Emissions = 1.80 x 10 -6 lbs/yr + 1.07 lbs/yr + 6.12 x 10 -4 lbs/yr
Total Emissions = 1.07 lbs/yr
13.0 Laminator (Cavity)
Methylenebis (phenyl isocyanate) (MDI) and polymeric diphenylmethane diisocyanate (PMDI)
mixture is used in conjunction with a polyol blend in the manufacture of laminator
boardstock. A two-component system, using a polyol blend (Component A) is mixed with a
MDI/PMDI mixture (Component B) through a special by designed nozzle is dispersed onto
laminator backing, enclosed between an upper and lower plate, and passed through an oven
for curing. This produces rigid foam sheeting that is cut to desired length and width.
Process Description
A two-component system, (Component A: polyol mixture; Component B: MDI/PMDI mixture),
is dispersed onto a laminator boardstock backing, forming a polyurethane, at a rate of 52
pounds/minute. This is passed through an oven at an average temperature of 123 o
F. The
line runs at a rate of 16 ft2 /piece with an average board thickness of 1.60 inches and
produces 24 pieces/minute.
The emissions from open processes can be estimated, when the volume of the mold is
known or can be determined, by calculating the total volume of air displaced from the
operations at the temperature of the process. A reasonable worst-case estimate of
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