The Treatment of Lubricant-Contaminated Soil: The Effects of Soil Flushing and Bioremediation
| Autor: | Ming-Sheng Wang, 王銘陞 |
|---|---|
| Rok vydání: | 2016 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 104 Petroleum products, such as gasoline, diesel, fuel oil, and lubricant, are classified as light non-aqueous phase liquids, LNAPLs, because of the low water solubility and less density（ρ）, ρ < 1. Once LNAPLs leaked into topsoil and then unsaturated aquifer, according to their properties, soil texture, field conditions, etc., they might spread in the soil and groundwater. Afterwards, that would increase the difficulty to remediate the contaminated zone. Lubricant is a kind of total petroleum hydrocarbons, TPHs. It’s generally composed of non-water-soluble linear or branched alkanes with carbon numbers 25 or more, normally in semi-solid or viscous liquid state, and a density of about 0.8 ~ 1 g / cm3. The main ingredient of lubricant is base oil, usually about 70%. Besides, thickeners, lubricant additives and other substances would usually be added in lubricant to form various products for different purposes. Therefore, the lubricant composition varies with market circulation. Since many physical and chemical properties and the environmental transport scenarios of lubricant haven’t fully understood due to the complicated composition, this study was to assess the physical method, such as soil flushing method, and biological method, such as biopile, for remediation of contaminated soil. The optimum parameters soil flushing test for the best removal of TPH from contaminated soil were（per 10 grams of soil）:（1）5% of Tween 80 for flushing solution,（2）flushing time of an hour,（3）the quantities of rinse solution and flushing solution in the rate of 3 mL/ mL, and（4）the quantities of flushing solution and soil in the rate of 3 mL/g. However, in terms of the amount of lubricating oil removed by solution with Tween 80 per mL （TPH-removed / mL-Tween 80）, it has the best economic benefits in the rate of 1 mL-Tween 80/g-soil. Namely, removal of TPH per mL Tween 80 is relatively high. The experiment results indicated that the addition of a commercially available agent could enhance the biodegradation of TPH in soils in comparison with other nutrients. Furthermore, addition of monosodium glutamate for nitrogen source, which is organic nitrogen nutrient, resulted in higher removal efficiencies in comparison of addition of peptone, which is also organic nitrogen nutrient. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|