Biodegradation of cycloalkanes under different redox conditions

露天开采和热水沥青提取作业有几个问题;重要的一个是大量流动细尾矿的管理。非水溶剂萃取（NAE）工艺具有通过产生高的沥青回收率、消除流体细尾矿的产生和减少对淡水消耗的依赖来减少油砂活动的环境影响的潜力。此外，使用NAE固体与原始土壤混合，矿区的复垦可能会更快。在沥青的NAE提取之后，大部分溶剂从该过程中回收并重新使用，但一小部分未回收的溶剂仍然与NAE固体结合并共沉积。找到一种安全快速地从NAE中去除未回收溶剂的方法将有利于矿山场地的回收。生物修复是一种经济有效的处理含烃尾矿的方法。利用土壤微生物群落降解NAE固体中残留溶剂的能力可以减少环境影响，如果NAE固体沉积在坑中或在高地或湿地情景下进行管理。在拟议的研究中，我们将模拟土坑（需氧/厌氧）、高地（需氧）和湿地通过在实验室中建立小规模的微宇宙实验，研究了不同氧化还原条件下，环戊烷和环己烷浸渍的NAE固体的生物修复（需氧，硝酸盐还原，硫酸盐还原和产甲烷）。拟议研究的结果将提供基本的科学信息，以制定管理沥青提取过程中产生的NAE固体的战略，并建立一个可持续的生态系统。

Surface mining and hot water bitumen extraction operations have several issues; the significant one is the management of enormous volumes of fluid fine tailings. Non-aqueous solvent extraction (NAE) process has a potential to reduce environmental impact of oil sands activity by yielding high recovery of bitumen, eliminating production of fluid fine tailings and reducing dependence on fresh water consumption. In addition, mine sites might be reclaimed more rapidly using NAE solids mixed with pristine soils. After NAE extraction of bitumen, the majority of the solvent is recovered from the process and re-used, but a small portion of unrecovered solvent remains incorporated and co-deposited with NAE solids. Finding a way to safely and rapidly remove the unrecovered solvent from NAE will benefit mine site reclamation. Bioremediation is a cost-effective method to treat tailings containing hydrocarbons. The ability to use soil microbial communities for the degradation of residual solvent from NAE solids could reduce the environmental impact if NAE solids are deposited in pits or managed under upland or wetland scenario. In the proposed research, we will be simulating soil-pit (aerobic/anaerobic), upland (aerobic) and wetland (anaerobic) site conditions by setting up microcosm experiments at small-scale in the laboratory and investigate bioremediation of NAE solids impregnated with cyclopentane and cyclohexane under different redox conditions (aerobic, nitrate-reducing, sulfate-reducing and methanogenic).The results of the proposed study will provide fundamental scientific information to develop strategies for managing NAE solids produced during bitumen extraction process and establishing a sustainable ecosystem on reclaimed sites.