Modifying Bitumen Extraction to Lower Environmental Impacts
Funded through ERA #2: Oil Sands Innovation in 2018, MEG Energy developed a pilot of their enhanced modified vapour extraction (eMVAPEX) technology. EMVAPEX, an extension of MEG’s patented eMSAGP (enhanced modified steam and gas push) technology, is intended to modify the steam assisted gravity drainage (SAGD) process to be more sustainable by minimizing environmental impacts to land, air and water.
SAGD is an energy intensive oil recovery process that requires significant investments in steam generation and water treating capacity. Steam is generated using a series of stationary combustion sources consuming fuel such as natural gas or mixed fuel gas; therefore, reducing the steam generation requirements per barrel of production is key to lowering a facility’s greenhouse gas (GHG) intensity.
The eMVAPEX technology is a solvent-assisted process that increases bitumen production and recovery, as well as reduce GHG and water use intensities by reducing the steam to oil ratio (SOR). In this process, propane is injected in lieu of steam after the initial SAGD operation when bitumen recovery reaches approximately between 20 and 30 per cent. The injected propane does two things the steam was doing: (1) it maintains reservoir pressure by taking up void space and (2) it mobilizes the bitumen by mixing with the it and reducing the viscosity. By using eMVAPEX, the resulting overall GHG emission intensity could be reduced by up to 43 per cent and bitumen production could increase by 75 per cent.
Overcoming Challenges to Achieve Efficient Commercial Operations
Overall, this project demonstrated the technical viability of eMVAPEX with the successful implementation and operation of the technology across several pilots. The project experienced a few challenges that will help to inform future installations of this technology:
- In the beginning, the eMVAPEX control system lacked a clear “control narrative”, or an extensive technical guide. This led to delays in starting the compressor. To prevent delays, the control narrative from the vendor should be made a required deliverable and reviewed by the engineering and procurement contractor.
- The technology required operational changes relating to the compressor component of the eMVAPEX operation, but because the compressor wasn’t assembled on site, this led to communication and execution challenges. For future projects, operators should be engaged early in the process to assess the risk, maintenance and operating costs.
- During operation, a significant amount of gas is produced, as propane mostly exists in a gaseous form. This caused some of the wells to experience something known as “gas coning”, which impacts the well’s productivity. To solve this issue, the project operators installed casing gas meters to monitor the gas in real time and optimize production without relying on standard tests that only happened every two weeks.
What’s next?
Since the project’s completion in 2020, MEG Energy has continued piloting activities to evaluate the performance, including a strategy to maximize the recovery of the retained propane in the reservoir. Solvent-assist production has reached full commercialization, and MEG is now contemplating further commercialization of the eMVAPEX technology. The success of this project demonstrates eMVAPEX is a promising technology and commercially ready. Further commercialization and market impact are dependent on costs, the price of carbon and the emission reduction targets of oils sands companies.