FIBER OPTIC SENSOR FOR IN-SITU AND REALTIME MONITORING OF TRANSPORT OF GAS PHASE OZONE IN UNSATURATED POROUS MEDIA

Jung, Haeryong; Choi, Heechul

doi:2005.10.2.71

Environmental Engineering Research 2005;10(2): 71-78. DOI: https://doi.org/10.4491/eer.2005.10.2.071

FIBER OPTIC SENSOR FOR IN-SITU AND REALTIME MONITORING OF TRANSPORT OF GAS PHASE OZONE IN UNSATURATED POROUS MEDIA

¹Department of Civil Engineering, University of Waterloo 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1
²Department of Environmental Science and Technology, Gwangju Institute of Science & Technology (GIST), Oryong-dong, Buk-gu, Gwangju, 500-712 South Korea

Corresponding Author: Heechul Choi ,Tel: +82-62-970-2441, Fax: +82-62-970-2434, Email: hcchoi@gist.ac.kr

Received: October 8, 2004; Accepted: April 11, 2005.

ABSTRACT

A series of column experiments was conducted to develop a monitoring system for in-situ and realtime measurement of ozone transport in unsaturated porous media using a fiber optic sensor. The calibration of the fiber optic transflection dip probe (FOTDP) system was successfully carried out at various ozone concentrations using a column with length of 30 cm and diameter of 5 cm packed with glass beads, which don't react with gaseous ozone. The breakthrough curves (BTCs) of ozone were obtained by converting the normalized intensity into ozone concentration. The FOTDP system worked well for in-situ monitoring of gas phase ozone at various water saturations and in presence of soil organic matter (SOM). However, the FOTDP system did not measure the ozone concentration at more than 70% water saturation.

Keywords: fiber optic sensor | transflection dip probe | unsaturated porous media | ozone