Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1021/es062890+
Title (Primary) Kinetic gas-water transfer and gas accumulation in porous media during pulsed oxygen sparging
Author Balcke, G.U.; Meenken, S.; Hoefer, C.; Oswald, S.E.
Source Titel Environmental Science & Technology
Year 2007
Department HDG
Volume 41
Issue 12
Page From 4428
Page To 4434
Language englisch
Abstract Gas-water mass transfer and the transport of dissolved gases in variably saturated porous media are key processes for in-situ remediation by pulsed gas sparging. In this context, gas dissolution tests were conducted during pulsed oxygen gas injection into sand columns. The columns were recharged with anoxic water, effluents were analyzed for dissolved O2, and tracer tests were performed to detect accumulation of trapped gas. In a second series oxygen gas was blended with sulfur hexafluoride (SF6), and O2 and SF6 breakthrough curves were recorded. To interpret experimental results, a numerical model was applied that simulates multi-species kinetic mass transfer during gas dissolution. The model predicted breakthrough curves of dissolved gas species and delivered spatially resolved values for gas phase accumulation and composition, which are not directly accessible experimentally. It was shown how dissolved nitrogen accumulates increasingly in trapped gas phase and inhibits its complete dissolution, in case the pulsed gas injections were operated based on O2 breakthrough only. Accumulation of nitrogen also retarded dissolved oxygen transport and thus oxygen breakthrough. Experiments plus modeling demonstrated that SF6 measurements are highly sensitive to the gas dissolution processes, and provide a more sensitive criterion for determining gas injection frequencies during pulsed biosparging.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=1627
Balcke, G.U., Meenken, S., Hoefer, C., Oswald, S.E. (2007):
Kinetic gas-water transfer and gas accumulation in porous media during pulsed oxygen sparging
Environ. Sci. Technol. 41 (12), 4428 - 4434 10.1021/es062890+