Mater L, Sperb R M, Madureira L A S, Rosin A P, Correa A X R, Radetski C M
Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900, Brazil.
J Hazard Mater. 2006 Aug 25;136(3):967-71. doi: 10.1016/j.jhazmat.2006.01.041. Epub 2006 Feb 21.
In this study sequential steps were used to treat and immobilize oil constituents of an oil sludge-contaminated soil. Initially, the contaminated soil was oxidized by a Fenton type reaction (13 wt% for H(2)O(2); 10mM for Fe(2+)). The oxidative treatment period of 80 h was carried out under three different pH conditions: 20 h at pH 6.5, 20 h at pH 4.5, and 40 h at pH 3.0. The oxidized contaminated sample (3 kg) was stabilized and solidified for 2h with clay (1 kg) and lime (2 kg). Finally, this mixture was solidified by sand (2 kg) and Portland cement (4 kg). In order to evaluate the efficiency of different processes to treat and immobilize oil contaminants of the oil sludge-contaminated soil, leachability and solubility tests were performed and extracts were analyzed according to the current Brazilian waste regulations. Results showed that the Fenton oxidative process was partially efficient in degrading the oil contaminants in the soil, since residual concentrations were found for the PAH and BTEX compounds. Leachability tests showed that clay-lime stabilization/solidification followed by Portland cement stabilization/solidification was efficient in immobilizing the recalcitrant and hazardous constituents of the contaminated soil. These two steps stabilization/solidification processes are necessary to enhance environmental protection (minimal leachability) and to render final product economically profitable. The treated waste is safe enough to be used on environmental applications, like roadbeds blocks.
在本研究中，采用了一系列步骤来处理和固定受油泥污染土壤中的油成分。首先，通过芬顿型反应（H₂O₂为13 wt%；Fe²⁺为10 mM）对污染土壤进行氧化。在三种不同的pH条件下进行80小时的氧化处理：pH 6.5下20小时，pH 4.5下20小时，pH 3.0下40小时。将氧化后的污染样品（3千克）与粘土（1千克）和石灰（2千克）一起稳定固化2小时。最后，用沙子（2千克）和波特兰水泥（4千克）对该混合物进行固化。为了评估不同工艺处理和固定受油泥污染土壤中油污染物的效率，进行了浸出性和溶解性测试，并根据巴西现行的废物法规对提取物进行了分析。结果表明，芬顿氧化工艺在降解土壤中的油污染物方面部分有效，因为多环芳烃（PAH）和苯系物（BTEX）化合物存在残留浓度。浸出性测试表明，先进行粘土 - 石灰稳定化/固化，然后进行波特兰水泥稳定化/固化，在固定污染土壤中难降解和有害成分方面是有效的。这两个稳定化/固化步骤对于加强环境保护（最小化浸出性）和使最终产品具有经济收益是必要的。处理后的废物足够安全，可用于环境应用，如路基砌块。
