Development of a LCA Screening Tool: Assessment of Biochar in the Removal of Organic Carbon in SAGD Produced Water
Creators: name: Bess-Ouko, Claudia
Publisher: name: Graduate Studies
Year: 2014
Subjects: subject: Engineering--Environmental
subject: LCA
subject: Produced water

description: Alberta’s oil sands is considered essential to both the Province’s as well as Canada’s continued economic growth and (their) energy stability. Development of the resource faces both opportunities and challenges which include among others, the investment climate and global growth in oil demand, and environmental concerns which have been raised by a number of stakeholders. To date, development of the resource is primarily through a water-intensive process making water management a major environmental focus for the industry, adding to the environmental challenges which the industry is facing. Accordingly, remediation of the industry’s largest waste per volume, produced water, using biochar is examined from a life cycle perspective. Life Cycle Analysis is a holistic methodology used in evaluating both the environmental and economic consequences of a process, product, or a particular activity, over its entire life cycle. A life cycle approach accounts for all the resources required and their resultant outputs during the life of the process. The life cycle of SAGD produced water management using biochar is examined within a boundary extending from the acquisition of raw materials used to generate biochar, through its productive use, to its end of life (cradle-to-grave) management. Using life cycle analysis, a framework is developed and applied to estimate and evaluate the environmental and economic impact(s) of deploying the proposed technology for remediation of SAGD produced water. The framework provides insight into the proposed system – production of biochar and the by-products of carbonisation, and their incorporation into the SAGD produced water remediation process. The current research work examines the carbon abatement potential of using biomass technology in remediating SAGD produced water through estimating GHG emissions, energy production as well as the economic consequences. The study shows that a system approach is desirable to maximise the benefits which may be accrued from using products from the carbonisation of biomass in managing SAGD produced water. That is, both the product (biochar) and by-products (syngas/bio-oil) need to be incorporated in the treatment process. A system approach shows that employing biochar as a treatment option, based on the technology and the desired removal rate, results in up to 80kg CO2e being abated per m3 of produced water remediated and a 1% reduction in the overall GHG emissions for the SAGD process. The study also shows a minimum cost of abatement of $80/tonne CO2e compared with the current Alberta carbon tax of $15/tonne CO2e, to make the project economically competitive. Surplus energy of 8000 MJ/m3 of treated SAGD produced water, may be available for use to offset energy requirements at the SAGD facility. The study yields an environmental true-cost-of-ownership, enabling better informed decision making, highlighting the importance of a carbonisation systems approach to maximising the value which can be attained in using biochar to remediate SAGD process water.