Control of Volatile Organic Compounds Emissions from Manufacturing

Footnotes for Table E-1
astandad conditions for flare design and cost calculations: 70°F and 1 atm.
b~uxiliary natural gas requirement assumes 300 Btulscf minimum lower heating
value necessary to assure 98 percent destruction in accord with
the results of the Joint CMAIEPA flare testing program, and lower heating value
of natural gas of 930 Btulscf at 70°F (1000 Btulscf at 32OF). From an energy
balance
Q (scfm) = 300 - LHVwg (Btulscf)
I
"9
LHVng (BtuIscf) - 300
x Qwg (scfm)
C~emperatureof mixture approximated by assuming unifotm specific heats
per unit mass.
I"
d~rom Envi roscience (Reference 1, Appendix A)
[ (2.72 x loe3) x QflSg (lb/hr) x
i n =
(Twg (OF) + 460)/nWfl.g
,lap (in. H20)
Fran the Envi ronscience equation for flame angle,
Ap (in. H20) = 55 [Ye (fpr)/~60]2 = (1.818 x ye2
In accord with the results of the Joint CMA/EPA flare testing
program:
Ve = 60 fps
Substituting,
D (in.)=
(2.72 x x Qflag (scflmin) x HYfl .g (lbllb mole)x(60 minlhr) (Twg + 460)/Rf1.g1 li
(387 scf at 70°Fllb-mole) x J(1.818 x (60)~ 1
Which simplifies to the relationship given.
e~elect next larger standard size than calculated diameter unless calculated diameter is
within 10% of interval between next smaller and next larger size, if so, select next
smal ler standard size.
f~ran Enviroscience eauation for D qiven in footnote d above.
I
t
t (2.72 x lo-') x Qflmg (scfhint) x HWfl.g (lbllb-mole) x (60 minlhr) J(T*,~ + 460)/NWfl.g
ap (in. H20) =
(387 scf at 70°F/l b-mole) x 0'
I'