AWWA ACE70778

This powerpoint presentation begins by providing a brief overview of the motivation behind this study: volatile organic compounds (VOCs) cause significant adverse effects onhuman health and the environment; they are important indoor air pollutioncontaminants; and, largely used in industrial operations assolvents, VOCs are a common source forsubsurface contamination of drinking watersupplies. Conventional and alternative treatmenttechnologies for VOC removal and their disadvantages are listed, along with the challenges of TiO₂ Photocatalysisfor large scale implementation. Research objectives are presented: to design a photocatalytic reactor that can efficientlyremove VOCs in the gas and aqueous phasessimultaneously; and, to overcome major difficulties to implement PCO atthe large scale. The proposed treatment system is presented, including: the reactor(TPOT) with toluene as the target contaminant; commingled packing; STCs characterization; UV intensity distributionin TPOT; single phase adsorption oftoluene in TPOT; gas phase toluenephotocatalysis; aqueous phase toluenephotocatalysis; two-phase toluenephotocatalysis; and, parameters affecting tolueneremoval in two-phase system. Conclusions indicate that: wetting of the packing completely inhibited gasphase toluene photocatalysis; the oxidation of toluene is at the surface of thecatalyst and not in the bulk phase; when both phases are flowing simultaneously inthe TPOT, the conversion of toluene occurs atthe liquid/catalyst interface; higher removals than those found in the singlephase system can be achieved in the two phasesystem under optimum operating conditions; main advantage of two phase system isversatility, it can handle fluctuations to avoidstressing or overloading the system; and, although designed for VOCs, TPOT resultsshow the system's potential for removal of lowHenry's constant compounds. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

24

File Size:

1 file , 2.2 MB