MDI Emissions Reporting Guidelines for the ... - Polyurethanes

MDI Emissions Reporting Guidelines for the Polyurethanes Industry
emissions can be made based on the volume, number of pieces produced per year and the
maximum temperature.
The enclosed process losses can be estimated from the following expression:
Where:
L c = V air * (1 / 359) * (273.15 / T proc ) * (VP MDI / 760) * M w * K MDI
Lc = emissions lb/yr
Vair = annual volume of displaced air in ft3 /yr
Tproc = process temperature in K (maximum temperature of the MDI)
VPMDI = vapor pressure of MDI in mm Hg. at process temperature
Mw = 250.26 (this is the molecular weight of MDI)
KMDI = adjustment factor to the vapor pressure that is a function of MDI
concentration in the feedstock and the temperature
359 = the molar volume of an ideal gas in ft3 /lb-mole @ 0 o
C and 1atmosphere
Step I: Calculate Annual Volume of Displaced Air (V air )
Vair = (Area/piece)(No. Pieces/yr)(Thickness)
Vair = (16 ft2 )(24 pieces/min)(60 min/hr)(24 hr./day)(365 days/yr)(1.6/12)
V air = 2.68 x 10 +7 ft 3 /yr
Step II: Calculate Maximum Process Temperature in K
The maximum temperature is the oven temperature of 123 o
F or;
T proc = 323.7 K
Step III: Determine vapor Pressure of MDI @ 323.7 K (VP MDI )
The vapor pressure @ 323.7 K is 1.92 x 10 –4 mm
Step IV: Determine Adjustment factor (K MDI )
Therefore:
Adjustment factor @ 323.7 K and 25% MDI is 0.38
Lc =
Lc =
Vair * (1 / 359) * (273.15 / Tproc ) * (VPMDI / 760) * Mw * KMDI (2.68 x 10 +7 ft3 /yr.)(1/359)(273.15 K /323.7 K)(1.92 x 10 –4mm/760) (250.26)(0.38)
Lc = 1.534 lbs/yr
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