The effect of age on petroleum hydrocarbon contaminants in soil for bioventing remediation

Abstract

An investigation was completed on the effects of petroleum contaminant aging in bioventing, a low cost and non-destructive in situ remediation method. Predicting site closure times remains a challenge in field applications, where the aged compounds are known to be sorbed into the soil, decreasing their bioavailability. Wet soil spiked with a known concentration of synthetic gasoline was aged in a refrigerator for 300 days. 150 g respirometers and 80 kg bioventing reactor degradation experiments were performed.After aging, a constant degradation rate at the 80 kg scale, varying from 0.12 𝑑 −1 to 0.133 𝑑 −1 , was observed. In the 150 g respirometer, there was an increase in biodegradation rate, from 0.0787 𝑑 −1 to 0.1943 𝑑 −1 . Microbial acclimatization during the aging process of wet soil was a key factor in both experiment.iii ACKNOWLEDGEMENTS This project would not have been possible without the help and support from all the important people I have received over the past two years. Sincere thanks to my supervisor, Dr. Richard Zytner, whose guidance and understanding throughout the entire project has helped me understand that any problem can be solved. His knowledge and experience were essential in the success of this project. I would also like to thank my advisory committee, Dr. Bassim Abbassi, whose valuable suggestions and feedback elevated this study and reminded me to take a step back to examine the problem with a different point of view.Furthermore, many thanks to the Natural Science and Engineering Research Council (NSERC) of Canada for providing the funding for this research project.To Joanne Ryks and Ryan Smith, I owe all my gratitude for providing support and assistance during the experimental phase of the project. Their suggestions and technical knowledge were an immeasurable help. Many thanks to Professors Hung Lee and Zeny Feng for their insights on microbiology and statistical analyses respectively, who helped to point me in the right direction, and to Lucia Costanzo, from the Data Resource Center, who was infinitely patient in answering all my statistical questions.I would like to thank the friends I've made during this journey; the joyful memories and mutual commiseration brought life into these few years as I transplanted myself into a new city. I cherish these connections and hope they remain strong as we part ways. To my friends and family who have supported me from afar, thank you for your continual understanding and encouragement. And to my best friend and the light of my life, thank you for always being there for me, for supporting my every decision, for

Groundwater quality

“…Bioventing process is a combination of soil venting and aerobic bioremediation to remove light and middle distillate hydrocarbons from vadose zone of groundwater table (Brusseau, 2019; Sharma, 2019). This process focuses on the minimization of hydrocarbon volatilization, while soil venting removes the volatile organic compounds and the aerobic biodegradation takes place by providing oxygen to sustain microbial activity in the vadose zone (Xiao & Zytner, 2019). Eslami and Joodat (2018) reported that bioremediation of ethylbenzene using bioventing along with bio‐sparging method showed about 60% reduction in the amount of ethylbenzene at the depth of 7 m in 40 days.…”