Impact of Aged Contamination on Bioventing Performance

被石油碳氢化合物污染的地点是一个世界性的挑战。场地修复是一项大生意，业主和政府正在寻找成本效益高、但对环境负责的方法来清理这些场地。生物通风是一种生物修复方法，它被归类为生物刺激方法，在土壤中添加氮气来刺激土壤中的石油降解物，以降低石油烃污染水平。然而，需要进行研究来确定陈旧的泄漏如何影响补救工作。具体地说，老化如何影响降解率、将实验室结果推广到现场时的放大系数以及代谢产物在降解过程中的发展？使用200克呼吸器和4公斤反应堆的降解研究将用于调查使用合成汽油的不同类型的老化程序和持续时间。两种反应器尺寸的不同生物通风条件将允许在不向土壤中添加改良剂时确定降解率，使用营养物质和生物炭等改良剂评估降解率，作为老化函数的提取效率，以及识别可能的代谢物形成。将一级降解率与提取效率和代谢物形成数据进行比较，将确定关键因素。由此产生的老化数据将确定对生物利用度的影响，改进数十年污染场地的生物通风实施。从实验室实验中获得的降解率将使三维生物通风模型的开发成为可能。这一模型将为顾问提供一种工具，他们可以通过该工具预测给定地点的生物通风效果，并估计关闭所需的时间，这是网站所有者和政府官员继续提出的问题。拥有这样的工具可以帮助加拿大和世界各地具有成本效益的石油污染场地的补救工作，提供许多就业机会。

Sites contaminated with petroleum hydrocarbons are a challenge worldwide. Site remediation is big business, with owners and governments looking for cost effective, yet environmentally responsible methods to clean up these sites. Bioventing is such a remediation method that it is classified as a biostimulation approach, where nitrogen is added to the soil to stimulate the petroleum degraders in the soil to reduce the petroleum hydrocarbon contamination level. However, studies are needed to determine how aged spills impact remediation efforts. Specifically, how does aging affect the degradation rate, the scale-up factor when extending the lab results to the field and the development of metabolites through the degradation process? Degradation studies using 200 g respirometers and 4 kg reactors will be used to investigate different types of aging procedures and durations using synthetic gasoline. Various bioventing conditions for both reactor sizes will allow determination of the degradation rate when no amendments are added to the soil, evaluation of degradation rate with amendments like nutrients and biochar, extraction efficiency as a function of aging and identification of possible metabolite formation. Comparing the first order degradation rates, along with extraction efficiencies and metabolite formation data will identify the critical factors. The resulting aging data will identify the impact on bioavailability, improving the implementation of bioventing at sites with decades old contamination. The degradation rates obtained from the laboratory experiments will allow development of a 3-D bioventing model. This model will give consultants a tool by which they can predict the effectiveness of bioventing for a given site and estimate the time needed to attain closure, a question site owners and government officials continue to ask. Having such a tool can assist with the cost effective remediation of petroleum contaminated sites in Canada and the world, providing many job opportunities.