An Update on Joslyn lease: First SAGD Facility Using Evaporators, Drum Boilers, And Zero Liquid Discharge Crystallizers To Treat Produced Water

摘要

Steam Assisted Gravity Drainage (SAGD) is a technique of heavy oil recovery used on oil sands in Alberta, Canada. Steam is injected down hole in the reservoir and the steam fluidizes the heavy oil and allows the oil/water mixture (emulsion) to be brought to the surface. The oil is recovered as product and the produced water is de-oiled and treated for reuse in steam generation. To treat de-oiled produced water, surface facilities use traditionally a combination of warm or hot lime softening (WLS), filtration, and weak acid cation (WAC) ion exchange. The pre-treated water is recycled and sent to "Once Through Steam Generators" (OTSG) which produce an 80% quality steam. The steam-water mixture is sent through a series of separators to produce the 100% quality steam required for injection into the oil well. TOTAL E & P Canada has recently developed on Joslyn lease (Athabasca, Alberta, Canada) an alternative way of produced water treatment and steam generation. The process uses a mechanical vapour evaporation followed by standard drum boilers. This method of SAGD steam production is simpler to operate, cost effective, and results in increased oil production and water efficiency. In this way, TOTAL has taken the challenge of recovering all liquid waste streams for reuse in the plant, resulting in zero liquid discharge (ZLD). A zero liquid discharge process eliminates the need for deep well injection and minimizes make-up water requirements. This paper will give an understanding of the overall process and of the last operational experiences.