MDI Emissions Reporting Guidelines for the ... - Polyurethanes

Where:
MDI Emissions Reporting Guidelines for the Polyurethanes Industry
Q R = the evaporation rate in lb/min
U = the airflow speed in m/sec. This is the airflow in the vicinity
of the process
A spill = the area of the spilled material in ft 2
VP mdi = the vapor pressure of MDI in mm Hg at the spill temperature
T spill = the average evaporation temperature in K
M W = the molecular weight of MDI (250.26)
Kmdi = the adjustment factor to the vapor pressure that is a function
of MDI concentration in the feedstock and the temperature
The spill losses can be determined by multiplying the evaporation rate (QR) in lb/min
by the time the spill is on the ground and converting the calculated value to the
desired units:
Where:
Therefore:
L spill = Q R * t spill * (60)
L spill = the evaporation losses resulting from the spill in lb
Q R = the evaporation rate in lb/min
t spill = the time that the spill is on the ground in hours
Q R = represents the evaporation rate in lb/min
u = 8.94 m/sec
A spill = 1,000 ft 2
VP mdi = 1.733 x 10 -5 mm Hg
T spill = 302.6 K
M W = 250.26
K MDI = 0.56
Substituting the values into the equation:
Therefore:
Where:
Q R = 2.413 x 10 –5 lb/min
L spill = Q R * t spill * (60)
t spill = 20 hours
L spill = 2.896 x 10 –2 lb/yr
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