Produced water treatment process at crude oil and natural gas processing facilities

A method for producing a treated water stream, the method comprising steps for:

• receiving a feed water stream comprising at least one substance mixed in a water phase;
• and
• processing the feed water stream in a plurality of stages arranged in operation from a lowest temperature and pressure to a highest temperature and pressure, to produce the treated water stream and a concentrated stream,
• wherein each stage comprises a vessel, a heat exchanger, an evaporator, and a condenser,
• wherein operation of an external heat exchanger in each stage is directly fluidly coupled to waste heat or energy available from an external heat source, and wherein the external heat exchanger is configured to receive the waste heat or energy available from the external heat source to heat the feed water stream inside the vessel to partially evaporate water from the feed water stream at each respective stage, independent of the heat provided by the waste heat or energy available from the external heat source to the external heat exchangers at the other stages,
• wherein each evaporator is configured to evaporate an amount of water using one of direct heat or indirect heat, and
• wherein each condenser is configured to condense at least a portion of steam generated by a successive stage,
• wherein the receiving the feed water stream comprises
• receiving a produced water main stream,
• splitting the produced water main stream into a heating stream, which is used for heating purposes, and a produced water stream, which is used for the generation of treated water, and
• heating the produced water main stream, using the heating stream, before entering the heat exchanger of a first stage of the plurality of stages.