Environmental Engineering Reference
In-Depth Information
applications discussed above. Further laboratory work is needed for SPCC, although initial
indications are showing great potential for eliminating contaminants eficiently by com-
bining both forms of irradiation (that of ultrasound and UV light) to the inluent simulta-
neously. The common optimum operating conditions for sonochemical and photocatalytic
oxidation coupled with the similarity in the mechanism of destruction, leading to a pos-
sible synergism and the possible mitigation of some of disadvantages observed for indi-
vidual processing techniques due to the effects of the other technique, have prompted the
development of SPCC reactors.
The present work aims at novel reactor designs for large-scale operations and further dis-
cussion about hybrid techniques with the mechanism between sonochemistry and hetero-
geneous photocatalysis. Different reactor conigurations used for the hybrid technique need
to be further analyzed, and recommendations have already been made for the design of an
optimum coniguration using both techniques. An optimum set of operating parameters has
been based on the critical analysis of the available literature detailed in the references sec-
tion. It has also been observed that sonophotocatalytic oxidation indeed results in signiicant
enhancement of the oxidation intensity and thus the rates of degradation; however, its appli-
cation on a larger scale of operation is hampered, perhaps owing to high cost and the lack of
suitable design strategies associated with the sonochemical reactors. Future work is required
to eliminate the drawbacks associated with the sonochemical and/or SPCC reactors.
Acknowledgments
Tony Diego gratefully acknowledges helpful discussions with Gerald Pollock at the
University of Washington, Seattle.
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