| Summary: | 碩士 === 國立成功大學 === 環境工程研究所 === 82 === The wet scrubbing combined SOx/NOx removal system is already
one of promising air pollution control devices. In this study,
individual and simultaneous absorptions of SO2 and NO by
alkaline solutions of NaClO2 were performed to clarify the
reaction kinetics. The absorptions of diluted SO2 and NO as
encountered in flue gases in aqueous solutions of NaClO2 and
NaOH were carried out using a semi-batch stirred vessel with a
plane gas-liquid interface at 50℃. The concentrations of SO2,
NO, and O2 in the feed stream varied from 1000 to 3000 ppm, 300
to 800 ppm and 0 to 6 %, respectively. The experiments were
divided into seven parts. The first two, the liquid-side and
gas-side mass transfer coefficients of this system were
determined. The rest were tested to evaluate the effect of
operating parameters on the absorption rate, the reaction
kinetics of the reactants in both gas and liquid phases, and
the effect of competitions be- tween various reactants on the
mass transfer rate, in a simple DeSOx, simple DeNOx, and
combined SOx/NOx removal system, respectively. The results
indicated that the absorption of SO2 was entirely gas-film
controlled where NaOH concentration was greater than 0.1 M.
The reaction between NO and aqueous solutions of NaClO2 was
found to be first-order respect to NO and third-order respect
to NaClO2. The oxidative power of the sodium chlorite
decreased by adding NaOH. The absorption rates of NO slightly
increased with increasing temperature within 25~50℃. The gas
flow rate only affected the absorption rate of SO2 in the range
of this study. Adding SO2 would decrease the absorption rate
of NO in the combined SOx/NOx removal test. However, the
addition of NO had no effect on the absorption rate of SO2 .
Finally, the existence of O2 had no significant effect on the
absorption rates of SO2 and NO.
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