Experimental Study of Biodegradation of Ethanol and Toluene Vapors

1
max
Y ex
=
− 0.635 + 2δ
+ K
3δ
− 0.5
(5-15a)
matp
m
e
= (5-15b)
3 δ − 0.5
Equations (5-15a) and (5-15b) provide relations between the three energetic
parameters: K ,δ , m . If we assume that these three parameters are fundamental
ATP
parameters for the strain, then a similar model as derived above can be derived for other
substrates, and in this model the yield coefficients will be different functions of the
three energetic parameters. If the yield coefficients are experimentally determined for
growth on different substrates the energetic parameters can be estimated (Nielsen and
Villadsen, 2001). An important assumption in this approach is that the values of
parameters do not change with the carbon source, even though the functions change
with different carbon sources.
For continuous operation, at steady state, r = 0 , thus the following equations
can be obtained from Equation (5-14):
r r
φ = −θ
e
⋅ν
(5-16)
φ
e
= 1.27ν
+ ν
(5-16a)
1
2
φx = −ν 1
(5-16b)
where
φ
e
and φ x
are the flow of ethanol and biomass into the system (C-mol/L-h),
respectively. Therefore, by coupling Equations (5-14e), (5-14f) with Equations (5-16a)
and (5-16b), the relation between the flows of ethanol and biomass at steady state in
continuous mode can be expressed by (see Appendix D for detailed mathematical
derivations):
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