Yokogawa GC8000 Process Gas Chromatograph - Manual (Page 492)

App.E-19
IM 11B08A01-01E
(c) ASTM D3588-91
The GC8000 converts each peak result obtained in volume percent into the one in mole fraction,
and calculates the real heating value per unit volume, real heating value per unit mass, real
relative density, real gas density, compressibility factor and Wobbe index of the sample gas from
the ideal heating value per unit volume, ideal relative density, ideal gas density, compressibility
factor and summation factor of each peak.
Z = 1 – P(
) 2
x
i
∑
W =
d
H
V
H
V
= x
i
H
Vi
∑
x
i
=
x
Vi
Z
i
x
Vi
Z
i
∑
β
ii
id
H
m
= id
id
ρ id = x
i
r
Vi
∑
ρ id
id
H
V
id
H
v
~
Z
H
V
id
H
V
~ = H
m
r
H
V id
H
V
: real heating value per unit volume (gross or net)
H
V
: ideal gross (or net) heating value per unit volume
H
Vi
: ideal gross (or net) heating value per unit volume of component i
H
m
: real heating value per unit mass (gross or net)
H
m
: ideal gross (or net) heating value per unit mass
d : real relative density
d id : ideal relative density
d
i
: ideal relative density of component i
ρ : real gas density
ρ id : ideal gas density
ρ
i
: ideal gas density of component i
Z : compressibility factor
Z
i
: compressibility factor of component i
Z
a
: compressibility factor of air (0.9996)
β
ii
: summation factor of component i
x
i
: mole fraction of component i
x
Vi
: volume percent of component i
P : pressure (14.696psia)
W : Wobbe Index
id
id
id
id
id
d =
Z
d id Z
a
ρ =
Z
ρ id
d id = x
i
d
i
∑ id
=
=
Where:
2nd Edition : May 11, 2012-00
App.E