Fenton氧化技术处理稠油污染土壤

利用Fenton氧化技术对稠油污染土壤进行氧化处理,分析对后续微生物修复的促进作用。向1 000 g石油类含量为8%的稠油污染土壤中加入10.0 mL 18 mmol/L Fe2+溶液与10.0 mL 30%H2O2,反应时间为2 h。氧化处理后土壤中石油烃的总去除率可达到31.38%,胶质去除率为45.22%,沥青质去除率为51.26%,胶质的分子量由1 841下降到1 472,沥青质的分子量由5 831下降到5 073。Fenton氧化可使土壤酶活、各类微生物的数量及呼吸强度有不同程度的下降,但在氧化后30 d内,土壤各类微生物数量都超过了原有水平,其中细菌数量最高达到9.84×105CFU/g,是氧化前的数量的1.57倍。以上实验结果表明,Fenton氧化可以有效去除土壤中胶质和沥青质,并且使土壤中微生物的生长速率加快。因此,Fenton氧化能够促进后续的微生物修复。

Heavy oil-contaminated soils remediation by Fenton oxidation

Heavy oil-contaminated soil was treated by Fenton oxidation to improve subsequent microbial remediation effect. 5 mL Fe²⁺solution of 18 mmol/L and 10 mL H₂O₂ of 30% were added to 1 000 g heavy oil-contaminated soil of 8%, reacting for 2 h. The total removal rate of petroleum hydrocarbon could reach 31.38%, and the removal rate of colloid and asphaltene could reach 45.22% and 51.26%, respectively by Fenton oxidation. The colloid molecular weight dropped from 1 841 to 1 472, and the asphaltene molecular weight dropped from 5 831 to 5 073 through Fenton oxidation process. Fenton oxidation could reduce tenzyme activity, tmicrobial quantity and respiration intensity of the soil in different levels. The microbial quantities exceeded the original level after Fenton oxidation in 30 days, and the quantity of bacteria was up to 9.84×10⁵ CFU/g. From above results, it can be concluded that Fenton oxidation can effectively remove soil colloid and asphaltene, and accelerate growth rate of microorganisms in soil. Therefore, Fenton oxidation can promote the subsequent microbial remediation.