| Summary: | 碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 100 === Bioremediation for TPH contaminated soil is a commonly used in-situ technology. Although bioremediation is low cost and ecological concerned, it has high uncertainty come from long remediating time and land use value. Physic-chemical treatments such as in-situ chemical oxidation and surfactant-flush are then widely used on contamination sites. Lubricants are long-chain hydrocarbons. Compared to gasoline, diesel and other oil product, it is more difficult to be metabolized by microorganisms.
Treatment train concepts were selected in this study. Three different oil samples (mineral lubricant, used mineral lubricant and mixed waste oil from contaminated site) were used to prepare 50,000 mg TPH/kg dry soil spiking contaminated soil. Two stages, Bioremediation combined with/without Fenton-like treatments were used to examine the degradation.
In the 1st bioremediation stage, TPH spiking contaminated soils were mixed with N+P, sludge, TPH contaminated site soils, compost or Tween80. TPH degradations in soil were examined every 30 days for 150 days. After the 1st bioremediation stage for 150 days was over, the 2nd stage, biological stimulation and Fenton-like processes were go on to investigate differences between bioremediation and chemical oxidation. Fenton-like treatment was applied with 6% H2O2, which was approximately 35.28 mM .
In the 1st stage, the best soil TPH degradation was 26.45 % in mineral lubricant contaminated soil with N+P+sludge. The best soil TPH degradation was 66.49 % in mixed waste oil contaminated soil with N+P+sludge+TPH contaminated site soil. The best soil TPH degradation was 27.36 % in used mineral lubricant contaminated soil with N+P+sludge. Treatment N+P+sludge had positive influence on TPH biodegradation. Tween80 addition affects the microbial metabolism of TPH that slow the degradation.
In the 2nd stage, biological stimulation (17.73%) was higher than Fenton-like (17.45%) only in mineral lubricant contaminated soil. In mixed waste oil and used mineral lubricant contaminated soils, Fenton-like were higher than biological stimulation. According to hydrocarbons analysis, aliphatic in mineral lubricant, either biological or Fenton-like restorations were remained > 60%, while used mineral lubricant remained &;lt; 45%.
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