Mitigating GHG emissions from oil sands tailings through redox processes

通过氧化还原过程减少油砂尾矿的温室气体排放

基本信息

批准号：
543693-2019
负责人：
Siddique, Tariq
金额：
$ 9.27万
依托单位：
University of Alberta
依托单位国家：
加拿大
项目类别：
Collaborative Research and Development Grants
财政年份：
2020
资助国家：
加拿大
起止时间：
2020-01-01 至 2021-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=699687
关键词：
Mitigating GHG emissions oil sands

项目摘要

Surface mining of oil sands has a significant environmental footprint. Currently tailings ponds contain more than 1 billion m3 of fluid fine tailings (FFT) that need to be reclaimed. Expression of porewater from settling FFT contributes oil sands process-affected water to the water cap volume and chemistry. Tailings ponds are anaerobic and harbor microbial communities that degrade residual hydrocarbons in FFT producing greenhouse gases (GHG), primarily methane. Similarly, methanogenesis can continue in end-pit lakes where FFT is reclaimed under water and the conditions are aerobic near the surface. The overarching objective of this current project is to reduce net GHG emissions. A two-pronged strategy will be employed: 1) to understand the role of iron minerals and other redox compounds (nitrate and sulfate) in the inhibition of methanogenesis and 2) to understand the roles of these alternative electron acceptors, along with molecular oxygen (O2), in the oxidation of produced methane. Exploring the metabolic potential of indigenous microorganisms and investigating linkages between methanogenesis and iron, nitrogen, and sulfur cycling in the FFT will help develop strategies that will include in situ amendments of redox compounds and ex-situ application of redox processes to inhibit methanogenesis and stimulate methane oxidation. The approach will mitigate GHG emissions from tailings ponds and future end-pit lakes in the Athabasca Oil Sands region in Alberta, Canada.

油砂的露天开采具有显着的环境足迹。目前尾矿库含有超过 10 亿立方米的流体细尾矿 (FFT) 需要回收。沉降 FFT 表达的孔隙水将受油砂过程影响的水贡献给水盖体积和化学成分。尾矿池是厌氧的，含有微生物群落，可降解 FFT 中的残留碳氢化合物，产生温室气体 (GHG)，主要是甲烷。同样，产甲烷作用可以在终坑湖中继续进行，其中 FFT 在水下回收，并且表面附近的条件是有氧的。当前项目的总体目标是减少温室气体净排放量。将采用双管齐下的策略：1）了解铁矿物质和其他氧化还原化合物（硝酸盐和硫酸盐）在抑制产甲烷过程中的作用，2）了解这些替代电子受体以及分子氧的作用（ O2），在氧化产生的甲烷中。探索本土微生物的代谢潜力并研究 FFT 中产甲烷作用与铁、氮和硫循环之间的联系将有助于制定策略，其中包括氧化还原化合物的原位修正和氧化还原过程的异位应用，以抑制产甲烷作用并刺激甲烷产生氧化。该方法将减少加拿大艾伯塔省阿萨巴斯卡油砂地区尾矿库和未来终坑湖的温室气体排放。