Treatment of oil contaminated soil from a wyoming refinery
An oily soil sample was shipped from the refinery site to the test Laboratories on June 17, 1995. The sample was stored at 4 °C until testing began. The sample was in the form of a dense pasty mud, black in color, and consisted of oily residues mixed with what appeared to be bentonite clay. Characterization showed the following:
The oily nature of the sample precluded adding it directly to test reactors because it could not be transferred easily and could not be suspended in cold water. To prepare the tests, the oily soil was suspended in hot water in the amount of 200 grams per liter of water. In some cases, Tween-80 was used as a surfactant at a T-80 to soil ratio (w/w) of 1:10 as recommended by Janiyani, et al. (Chem. Tech. BiotechnoL, 1993). The final test characteristics of the soil suspension, T-80, and soil+T80 mixtures were as follows:
The test program consisted of two sets of aerobic respirometer tests, one set of anaerobic semi-continuous reactor tests, three batch anaerobic tests, and one set of four bench-scale slurry reactors. The project was considered complete as of July 17 but respirometer tests were continued through August 15. An analysis of the test results is given below.