MDI Emissions Reporting Guidelines for the ... - Polyurethanes

MDI Emissions Reporting Guidelines for the Polyurethanes Industry
SA = the total exposed surface area in M2 /day. This includes top and all
sides
tTF = the tack-free time in seconds
Kmdi = the adjustment factor
The open process losses are determined by multiplying the evaporation losses per day
by the number of days the process is in operation.
Therefore:
VPmdi = 2.281 x 10 -8 atm
Tproc = 302.6K
Mw = 250.26 (this is the molecular weight of MDI)
u = 0.91m/sec
SA = 10,234 M2 (This includes top and all sides)
tTF = 60 seconds
Kmdi = 0.56
Substituting the values into the equation:
W = 0.152 grams/day
W = (0.152 grams/day)(365 days/year) (1 lb./454 grams)
W = 0.125 lb/yr
4. Calculating Emissions from Mixing/Blending/Filling Process
Estimating emissions from a filling operation will correspond to the total volume of
air displaced from the containers at the filling temperature. The reasonable worstcase
scenario will be to assume that the volume of air displaced from the container
is saturated with MDI/PMDI.
The filling losses can be estimated from the following equation:
Where:
L fll = V air * (1 / 359) * (273.15 / T fill ) * (VP MDI / 760) * M w * K MDI * C blnd
Lfll = the emissions from the filling operation in lbs/yr
Vair = the annual volume of displaced air in ft3 /yr
Tfill = the temperature the material is charged or filled at in K
VP =
MDI
the vapor pressure of MDI in mm Hg at the charging/filling
Mw =
temperature.
the molecular weight of MDI (250.26)
6-10