Lime-Based Stabilization of Residual Petroleum Hydrocarbons in Contaminated Soils after Biodegradation

生物降解后污染土壤中残留石油烃的石灰基稳定化

• 批准号: 478374-2015
• 负责人: Chang, WonJae
• 金额: $ 1.82万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=579453
• 关键词: Lime; Based; Stabilization; Residual; Petroleum

Petroleum hydrocarbons are one of the most frequently identified compounds in contaminated sites in Canada. In general, indigenous hydrocarbon-degrading bacteria are often present in hydrocarbon-contaminated soils and groundwater, and active bioremediation and natural attenuation (intrinsic biodegradation) are therefore frequently considered cost-effective, minimally destructive site remediation strategies. However, the origin of the major limitation of bioremediation and natural attenuation is that hydrocarbon-degrading microorganisms must be able to access hydrocarbons in soil microenvironments. After bioremediation or natural attenuation, hydrocarbon concentrations often rebound and exceed environmental criteria in the soil due to the reduced bioaccessibility of hydrocarbons in the soil matrix, which minimizes microbial activity. Residual hydrocarbons can be gradually mobilized and leached out by climatic events such as seasonal soil freeze-thaw cycles and precipitation. The risk of hydrocarbon exposure for humans and wildlife is elevated during this slow process and cannot be predicted precisely. This represents a significant environmental concern for a large number of hydrocarbon-contaminated sites and lean oil sands tailings dump sites, most of which are passively remediated by intrinsic microbial activity. In collaboration with Graymont Western Canada Inc., Dr. Won Jae Chang's research group at the University of Saskatchewan is developing a stabilization post-treatment technology for residual hydrocarbons in soils that have undergone bioremediation or natural attenuation. In the proposed research, quicklime and hydrated lime will be tested as the key remedial agents for the stabilization technique. The lime products will be employed to enhance the volatilization of light hydrocarbons during exothermic pozzolanic reactions, immobilize heavy hydrocarbon fractions during lime cementation, and promote cation exchanges to remove adsorbed salts (mainly sodium chloride, a common co-contaminant) within biologically weathered, field-aged, petroleum hydrocarbon-contaminated soils.

石油碳氢化合物是加拿大污染场地中最常见的化合物之一。 一般来说，本土的碳氢化合物降解菌通常存在于碳氢化合物污染的土壤和 因此，地下水、积极的生物修复和自然衰减(固有的生物降解) 经常被认为是具有成本效益的、破坏性最小的现场补救策略。然而，它的起源 生物修复和自然衰减的主要限制是降解碳氢化合物的微生物 必须能够接触到土壤微环境中的碳氢化合物。经过生物修复或自然衰减后， 由于土壤中碳氢化合物浓度的降低，土壤中的碳氢化合物浓度经常反弹并超过环境标准 土壤基质中碳氢化合物的生物可获得性，从而最大限度地减少微生物的活动。残留碳氢化合物 可被季节性土壤冻融循环等气候事件逐渐动员和淋失 降水。在这个缓慢的过程中，人类和野生动物接触碳氢化合物的风险会增加。 而且不能被准确预测。这代表着大量的环境问题 碳氢化合物污染场地和贫油砂尾矿场，其中大部分是被动修复的 通过内在的微生物活动。与Graymont Western Canada Inc.合作，Won Jae Chang博士的 萨斯喀彻温大学的研究小组正在开发一种稳定的后处理技术 经过生物修复或自然衰减的土壤中的残留碳氢化合物。在建议的 研究表明，生石灰和消石灰将作为稳定技术的关键补充剂进行试验。 石灰产品将用于促进轻烃在放热过程中的挥发 火山灰反应，在石灰胶结过程中固定重烃组分，并促进阳离子 交换去除生物体内的吸附盐(主要是氯化钠，一种常见的共同污染物) 风化、田间老化、受石油烃污染的土壤。