Abstract

The quantity of the outdoor air for building ventilation has a direct negative effect on the
building energy cost and the environment. Also, there are plenty of pollutants in an
indoor environment which affect building occupants’ health and comfort. This is one of
the concerns in design of sustainable buildings which leads to a balancing act between
indoor air quality (IAQ) and energy cost.
Ultraviolet photocatalytic oxidation (UV-PCO) is regarded as one of the salient
technologies for decomposition of pollutants, especially volatile organic compounds
(VOCs) and a viable alternative to activated carbon filters. Majority of the previous
research on UV-PCO was performed in an ideal bench top reactor and in ppm range of
VOCs. Also, limited research has been devoted to investigate the generation of UV-PCO
toxic by-products while this issue is one of the main drawbacks in design of sustainable
buildings.
The objectives of this study were to: (1) Develop a methodology for determining the
performance of UV-PCO technology using full scale experimental set-up; (2)
Qualification and quantification of generated by-products; (3) Comparing UV-PCO
performance either in presence or absence of ozone, and (4) Investigating the impact of
operational parameters.
Results showed UV-PCO method has better performance in presence of ozone using
VUV lamps, although some by-products generated only in presence of ozone. It was
found that among tested VOCs, ethanol and 1-butanol generated more by-products,
especially acetaldehyde. Some toxic compounds including formaldehyde and
acetaldehyde were generated in all cases. Increment of flow rate and relative humidity,
decreased the UV-PCO performance for ethanol oxidation. System performance was
significantly improved by increasing the number of reactors.