Experimental Study of Biodegradation of Ethanol and Toluene Vapors

CHAPTER FOUR- EXPERIMENTAL RESULTS
AND DISCUSSION
Introduction
This chapter will present and discuss the experimental results in the order of
mass transfer and air stripping results, followed by the bioremediation results. Since we
are dealing with air pollutants using a well-mixed bioreactor with the microorganisms in
the liquid phase, the substrates (ethanol and toluene in this study) have to transfer from
the gas phase into the liquid phase to be bioremediated. Moreover, due to high volatility
of the VOCs, we also need to know air-stripping effects in the process. Therefore,
before bioremediation experiments take place, experiments of mass transfer and air
stripping were carried out.
4.1 Mass Transfer
4.1.1 Mass Transfer of Ethanol and Toluene
For toluene, mass transfer kinetics can be described by Equation (4-1) (Lyman
et al., 1982):
dSt
dt
*
t
= k a × ( S − S )
(4-1)
L
t
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