Zheng Xue-Jing, Blais Jean-François, Mercier Guy, Bergeron Mario, Drogui Patrick
Institut National de la Recherche Scientifique (INRS-Eau Terre et Environnement), Université du Québec, 490 Rue de la Couronne, Québec, QC, Canada G1K 9A9.
Chemosphere. 2007 Jun;68(6):1143-52. doi: 10.1016/j.chemosphere.2007.01.052. Epub 2007 Mar 6.
Polycyclic aromatic hydrocarbons (PAHs) have been widely studied due to their presence in all the environmental media and toxicity to life. These molecules are strongly adsorbed on the particulate matters of soils, sludges or sediments because of their strong hydrophobicity which makes them less bioavailability, thus limiting their bioremediation. Different sludge treatment processes were tested to evaluate their performances for PAH removal from sludge prealably doped with 11 PAHs (5.5mg each PAH kg(-1) of dry matter (DM)): two biological processes (mesophilic aerobic digestion (MAD) and simultaneous sewage sludge digestion and metal leaching (METIX-BS)) were tested to evaluate PAH biodegradation in sewage sludge. In parallel, two chemical processes (quite similar Fenton processes: chemical metal leaching (METIX-AC) and chemical stabilization (STABIOX)) and one electrochemical process (electrochemical stabilization (ELECSTAB)) were tested to measure PAH removal by these oxidative processes. Moreover, PAH solubilisation from sludge by addition of a nonionic surfactant Tween 80 (Tw80) was also tested. The best yields of PAH removal were obtained by MAD and METIX-BS with more than 95% 3-ring PAH removal after a 21-day treatment period. Tw80 addition during MAD treatment increased 4-ring PAHs removal rate. In addition, more than 45% of 3-ring PAHs were removed from sludge by METIX-AC and during ELECSTAB process were quiet good with approximately 62% of 3-ring PAHs removal. However, little weaker removal of 3-ring PAHs (<35%) by STABIOX. None of the tested processes were efficient for the elimination of high molecular weight (> or = 5-ring) PAHs from sludge.
多环芳烃（PAHs）因其在所有环境介质中的存在及其对生命的毒性而受到广泛研究。由于这些分子具有很强的疏水性，它们会强烈吸附在土壤、污泥或沉积物的颗粒物上，这使得它们的生物可利用性较低，从而限制了它们的生物修复。测试了不同的污泥处理工艺，以评估它们从预先掺杂11种PAHs（每种PAH 5.5mg/kg干物质（DM））的污泥中去除PAHs的性能：测试了两种生物工艺（中温好氧消化（MAD）和同步污水污泥消化与金属浸出（METIX-BS）），以评估污水污泥中PAHs的生物降解情况。同时，测试了两种化学工艺（非常相似的芬顿工艺：化学金属浸出（METIX-AC）和化学稳定化（STABIOX））以及一种电化学工艺（电化学稳定化（ELECSTAB）），以测量这些氧化工艺对PAHs的去除效果。此外，还测试了通过添加非离子表面活性剂吐温80（Tw80）从污泥中增溶PAHs的情况。经过21天的处理期后，MAD和METIX-BS实现了最佳的PAHs去除率，三环PAHs的去除率超过95%。在MAD处理过程中添加Tw80提高了四环PAHs的去除率。此外，METIX-AC从污泥中去除了超过45%的三环PAHs，在ELECSTAB过程中效果也相当好，三环PAHs的去除率约为62%。然而，STABIOX对三环PAHs的去除效果稍弱（<35%）。所测试的工艺均不能有效地从污泥中去除高分子量（≥5环）的PAHs。
