Steam injection into deep underground formations has proven to be an effective method for EOR facilities producing heavy oil from non-minable oil-sand formation. It is typically done through SAGD, Steam Drive or by CSS. Most facilities generate waste liquids and consume natural gas. This paper proposes a method and system for producing steam for extraction of heavy bitumen with zero liquid discharge and with the ability to consume low grade fuel. The presented system includes "Direct Contact Steam Generation" (DCSG) used for direct heat transfer between combustion gas and contaminated liquid phase water for steam generation. The DCSG can be integrated into a commercially available pressurized boiler or gasifier for internally mixing the low quality water with the combustion gas and transferring the liquid water to gas. The DCSG can also be a separate entity, allowing the use of existing atmospheric boilers (like OTSG or industrial boilers). To recover the heat and the water from the DCSG discharge and to use it to generate additional BFW (Boiler Feed Water) for steam generation, a commercially available water distillation unit can be used: like an evaporator, MED (Multi Effect Distillation), MSF (Multi Stage Flash) or MVC (Mechanical Vapor Compressor). The water treatment plant discharge brine is recycled and consumed by the DCSG. Another advantage of the process is its ability to consume highly contaminated oily water and feed them directly to the DCSG. This capability simplifies the oil-water separation and reduces the amounts of chemicals normally used in this processes. The presented system can be integrated into an existing project as a new phase, with the advantage that all the liquid waste generated by old phases can be consumed by the DCSG providing an overall ZLD facility. The sludge waste of an existing hot or warm lime softener water treatment plant can be recycled to the combustion stage or to the DCSG and used to remove sulfur with petcoke or coal fired systems. Another advantage of the proposed solution is that any field facilities (like the pads, injection and production wells) will be unchanged, and will be similar design to standard well known facilities. The paper shows a clear solution to achieve an effective ZLD system that can use low grade water and low grade fuel.

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