Section of Environmental Technology, Wageningen University, 6700 EV Wageningen, The Netherlands; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 710055 Shaanxi Xi'an, China.
Chemosphere. 2011 Jun;84(2):272-7. doi: 10.1016/j.chemosphere.2011.03.044. Epub 2011 May 14.
Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidation leads to partial removal of highly contaminated soil, therefore chemical oxidation was investigated and optimized aiming at a subsequent bioremediation treatment. Chemical oxidation of cable oil was studied with liquid H(2)O(2) and solid CaO(2) as well as permanganate at pH 1.8, 3.0 and 7.5. Liquid H(2)O(2) most effectively removed cable oil at pH 7.5 (24%). At pH 7.5 poor oil removal of below 5% was observed with solid CaO(2) and permanganate within 2d contact time, whereas 18% and 29% was removed at pH 1.8, respectively. A prolonged contact time of 7d showed an increased oil removal for permanganate to 19%, such improvement was not observed for CaO(2). Liquid H(2)O(2) treatment at pH 7.5 was most effective with a low acid use and was best fit to a subsequent bioremediation treatment. To further optimize in situ chemical oxidation with subsequent bioremediation the effect of the addition of the iron catalyst and a stepwise liquid H(2)O(2) addition was performed. Optimization led to a maximum of 46% cable oil removal with 1469mM of H(2)O(2), and 6.98mM Fe(II) chelated with citric acid (H(2)O(2):FeSO(4)=210:1 (molmol(-1)). The optimum delivery method was a one step addition of the iron catalyst followed by step wise addition of H(2)O(2).
在许多欧洲国家，电缆绝缘油泄漏是导致高压地下电缆土壤污染的一个常见原因。由于污染的性质和存在的高浓度，原位修复这些污染非常困难。化学氧化导致高度污染土壤的部分去除，因此研究并优化了化学氧化，旨在进行后续的生物修复处理。在 pH 值为 1.8、3.0 和 7.5 时，用液体 H(2)O(2)和固体 CaO(2)以及高锰酸盐研究了电缆油的化学氧化。在 pH 值为 7.5 时，液体 H(2)O(2)最有效地去除了电缆油（24%）。在 2d 接触时间内，在 pH 值为 7.5 时，用固体 CaO(2)和高锰酸盐去除的油不到 5%，而在 pH 值为 1.8 时，分别去除了 18%和 29%。延长接触时间至 7d，高锰酸盐的除油率提高到 19%，而 CaO(2)则没有观察到这种改善。在 pH 值为 7.5 时，液体 H(2)O(2)处理具有低酸用量和最适合后续生物修复处理的特点。为了进一步优化原位化学氧化与后续生物修复的结合，进行了添加铁催化剂和分步添加液体 H(2)O(2)的效果优化。优化后，在添加 1469mM 的 H(2)O(2)和 6.98mM 柠檬酸螯合的 Fe(II)（H(2)O(2):FeSO(4)=210:1 (molmol(-1)))的情况下，最大去除了 46%的电缆油。最佳输送方法是先添加铁催化剂，然后再分步添加 H(2)O(2)。
