Climate Alliance Limited, C/o 1A Pasley St, Sunbury, 3429, Victoria, Australia.
J Environ Manage. 2022 Sep 1;317:115257. doi: 10.1016/j.jenvman.2022.115257. Epub 2022 May 27.
The objective of this study was to assess the suitability of onsite re-use of mature compost for landscaping and tree mulching, produced from the bioremediation of oily sludge from the refinery. Compost samples from the co-composting process were analysed for a range of contaminants, including a human health risk assessment fractionation (HRAF) of the remaining petroleum hydrocarbons, as well as a phytotoxicity test. The chemical characterisation demonstrated that the process removed more than 94% of the original petroleum hydrocarbons from the sludge, and the removal rates were high at 1155 mg/kg/day. The HRAF demonstrated no residual risks, posed by the petroleum hydrocarbons present in the compost to human health if used on-site when compared to the relevant Australian environmental investigation levels (ILs). However, the phytotoxicity assessment demonstrated that the compost was toxic to germinating lettuce. The gap in the literature this study addressed was to provide an estimate of the LD and no effect concentration (NEC) for the compost using a standard plant bioassay containing a range of residual (aged) and bioremediated refinery process wastes, including petroleum hydrocarbons. The values estimated for LD and NEC were approximately 125 and 43 mg/kg, respectively for compost containing residual petroleum hydrocarbon fractions, filling a gap in the current literature which has limited data on standard toxicity values that can be used in determining and informing commercial remediation strategies and their outcomes with aged sludges. Phytotoxicity was shown to be an important complement to conventional analyses and HRAF data when characterising the sludge, and understanding its potential for re-use. The novelty of the study is that it highlighted a gap in the complementary use of chemical and bioassay analyses for evaluating refinery waste remediation endpoints, which has potential for broader application to other projects.
本研究旨在评估从炼油厂油泥生物修复中生产的成熟堆肥就地再利用用于景观美化和树木覆盖的适宜性。对共堆肥过程中的堆肥样品进行了一系列污染物分析，包括剩余石油烃的人类健康风险评估分级（HRAF）以及植物毒性测试。化学特性表明，该工艺从污泥中去除了超过 94%的原始石油烃，去除率高达 1155mg/kg/天。HRAF 表明，与相关的澳大利亚环境调查水平 (IL) 相比，如果在现场使用，堆肥中存在的石油烃对人类健康没有残留风险。然而，植物毒性评估表明，堆肥对发芽的生菜有毒。本研究旨在填补文献中的空白，使用标准植物生物测定法评估堆肥的 LD 和无效应浓度 (NEC)，该方法包含一系列残留（老化）和生物修复炼油厂工艺废物，包括石油烃。对于含有残留石油烃馏分的堆肥，估计的 LD 和 NEC 值分别约为 125 和 43mg/kg，填补了当前文献中关于可用于确定和告知商业修复策略及其结果的标准毒性值的有限数据的空白，这些策略涉及老化污泥。植物毒性被证明是对常规分析和 HRAF 数据进行特征描述的重要补充，有助于了解其再利用的潜力。本研究的新颖之处在于，它强调了在评估炼油厂废物修复终点时，化学分析和生物测定分析的互补使用存在差距，这可能对其他项目具有广泛的应用潜力。
