challenge:含油土壤的耗氧反应

An oily soil from a refinery site contained 4.7% hydrocarbons by weight. The total COD of the soil was 55,000 mg/L. Tests were conducted by EnviTreat’s Environmental Engineers to determine if Tween-80, a surfactant, enhanced the biodegradation of the oily contaminants in the soil. Samples of the oily soil were added to individual test reactors. Tween-80 was added on one set of samples at a T-80:soil ratio （w/w） of 1:10. The tests were conducted for 52 days without interruption.
Oxygen uptake tests showed that Tween-80 enhanced the biodegradation of the organic materials in the soil sample. Without T-80, the 52-day oxygen uptake represented 30% of the COD while with T-80, the 52-day oxygen uptake represented 67% of the COD as shown in the accompanying figure. （All data have been corrected for dilution and for the contribution of seed organisms to the oxygen uptake）.