In-line measurement of trichloroethylene vapors using tin dioxide sensors
1998
Heron, C. | Zutphen, M. van | Enfield, C.G.
During thermally enhanced in situ remediation of soils and ground water, gas streams are generated with varying temperatures, moisture content, and organic compound concentrations. In this study, we evaluated the performance of tin dioxide sensors for measuring trichloroethylene (TCE) concentrations in gas streams from a thermally enhanced soil vapor extraction system. Temperature, pressure, moisture content, and vapor flow rates affected the resistivity of the sensors, and thus the signal. When fluctuations in these parameters were eliminated by condensing excess water and heating to a constant temperature prior to measurment, the sensors provided reliable in-line measurement of TCE concentrations. Gas tracers such as methane were easily monitored in-line, providing quick and inexpensive data on subsurface vapor flow velocities and direction.
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