MDI Emissions Reporting Guidelines for the ... - Polyurethanes

MDI Emissions Reporting Guidelines for the Polyurethanes Industry
Engineering Calculations
Core Box Step:
During this step, the MDI formulation is injected into the mold at ambient temperature. The
losses will correspond to the total volume of air displaced from the molds at the filling
temperature. A reasonable worst-case estimate of filling losses can be made based on the
total volume of MDI formulation consumed, the composition of the MDI formulation and the
injection temperature.
The core box losses can be estimated from the following expression:
Where:
Therefore:
L cb = V air * (1 / 359) * (273.15 / T cb ) * (VP mdi / 760) * MW * K mdi * C iso /100
Lcb = the emissions from the core box step in lb/yr
Vair = the annual volume of displaced air in ft3 /yr (at the filling temperature)
Tcb = he filling temperature in K
VPmdi = the vapor pressure of MDI in mm Hg at the filling temperature
MW = the molecular weight of MDI (250.26)
Kmdi = an adjustment factor to the vapor pressure that is a function of MDI
Ciso =
concentration in the feedstock and the temperature
the % of isocyanate feedstock in the total formulation. If only MDI/PMDI
material is filled then Ciso = 100%
L cb = V air * (1 / 359) * (273.15 / T cb ) * (VP mdi / 760) * MW * K mdi * C iso /100
Vair = 400,000 lbs Part 1 + 325,000 lbs Part 2= 725,000 lbs x 1 gal/10 lbs x 1
ft3 /7.45 gal
Vair = 9692 ft3 /yr
Tcb = the filling temperature in K = 20 o
C + 273.15 o
K = 293.15 o
K
VPmdi = the vapor pressure of MDI in mm Hg @20 o
C = 5.28 x 10 –6 mm Hg
MW = the molecular weight of MDI (250.26)
Kmdi = an adjustment factor to the vapor pressure that is a function of MDI
concentration in the feedstock and the temperature. 100 pure MDI is used in
the feedstock K =1.0
Ciso = the % of isocyanate in the total formulation. 325,000 lbs x 39% / 725,000lbs
Ciso = 0.04
L cb = (9692 ft 3 /yr)*(1/359)*(273.15/293.15)*(5.28 x10 -6 /760)*(250.26)*(1)*(.04)
L cb = 1.80 x 10 -6 lbs/yr
5-33