Project Overview
Funded through ERA’s Oilsands Innovation challenge in 2019, this project advanced and demonstrated high-temperature reverse osmosis (HTRO) technology capable of treating steam-assisted gravity drainage (SAGD) water at temperatures above 100°C to generate higher-quality boiler feedwater than is currently produced. Pilot testing at Suncor’s Water Technology Development Centre (WTDC) verified the technology’s technical operating range, reducing emissions and CAPEX while progressing the system to TRL 8.
Reducing Emissions by Improving Oil and Gas Water Treatment
HTRO is a membrane-based water treatment technology designed to operate under SAGD-relevant conditions such as temperatures above 100°C, high pressure, and variable water chemistry. The technology reduces emissions by making the SAGD water-treatment and steam-generation cycle more energy-efficient. In a conventional SAGD facility, produced water must be cooled below 90°C for warm or hot lime softening, a type of water treatment which uses limewater to promote a precipitation reaction, removing deposits. The water is then reheated for steam generation. Overall, this incumbent process creates large heat losses and increases natural-gas use. Because HTRO operates above 100°C, it treats water at near-process temperatures, eliminating most of this cooling-reheating duty and reducing the amount of fuel required in the boilers. The high-quality boiler feedwater produced by HTRO also enables the use of more efficient hybrid or drum boilers that generate higher-quality steam with much lower blowdown. This means less water must be heated overall, further lowering fuel consumption and associated GHG emissions. In addition, better water quality leads to smaller blowdown volumes and reduced energy demands for blowdown water handling and treatment. Together, these changes improve thermal efficiency across the facility and translate into a modelled 5 to 10 per cent reduction in total GHG emissions for greenfield SAGD operations.
Advancing Membrane Technology for Water Treatment
The project unfolded in two major phases: laboratory and bench-scale development of high-temperature membranes, followed by a full pilot demonstration at the Water Technology Development Centre. Phase 1 successfully established membrane materials, module designs and membrane-sample-testing protocols at temperatures near 100°C. These results informed the design of full-scale elements and provided validated performance data for SAGD central processing facilities modelling. Phase 2 focused on field-scale operation of a five-cubic-meter-per-hour pilot skid under multiple operating modes, feed streams and recycle strategies. The pilot achieved continuous operation at temperatures up to 105°C, demonstrated a strong ability to reject silica and organics, confirmed membrane robustness and produced data showing 5 to 10 per cent total GHG reduction potential in greenfield SAGD configurations.
Overall, the development and execution of this pilot were successful in highlighting the potential use of a membrane for boiler feedwater production in the SAGD process. However, the project encountered challenges in understanding the most effective modes and conditions of membrane operation. For example, the first stage of total organic content (TOC) removal initially demonstrated positive results, but performance was not as successful on the second stage. This challenge led the team to adjust membrane installation methods, optimize chemical dosing and refine operating modes to improve the organic removal. Additionally, the WTDC was closed early, shortening the available runtime and requiring the team to prioritize essential testing. Despite the WDTC closure, the main objectives—mapping the operating range, validating high-temperature performance and proving feasibility across feed types—were all completed. These experiences can help inform future development and installation of HTRO under SAGD conditions.
What’s next?
By project completion in 2024, the team successfully advanced the technology to TRL 8, demonstrating HTRO’s use in a SAGD context. While successful at this scale, there are still challenges with the commercialization of membrane technology at high temperatures. Further work is ongoing to assess how to integrate membrane treatment operations into future assets and reduce, replace or supplement existing warm lime softener evaporator-based processes to potentially reduce future emissions. The current test skid has been removed from the WTDC and is planned to be reinstalled at a new facility to continue de-risking this technology.