Flume Tests on Hydrocarbon Reaeration Tracer Gases

Laboratory studies of the modified tracer gas technique were conducted in a tilting, recirculating flume. Simultaneous rates of hydrocarbon gas desorption and reaeration were measured for three flow conditions. The hydrocarbon gases used were propane ($C_3{H}_8$) and ethylene ($C_2{H}_4$). The ratio of the desorption rate coefficient for propane to the reaeration rate coefficient was found to be independent of flow conditions. The same was found to be true for the ratio of the ethylene desorption rate coefficient to the rearation rate coefficient. The results of the flume tests were compared with two sets of mixing tank studies of hydrocarbon desorption and reaeration. Results were comparable for all tests.