Produced water degassing using ejector

A method of treating a produced water (PW) stream, the method comprising:

• performing a gas oil separation process of a hydrocarbon-water mixed stream at a gas oil separation plant (GOSP) to generate a PW stream comprising a dissolved gas, the dissolved gas comprising at least one C1-C5 hydrocarbon;
• splitting the PW stream into a first stream and a second stream;
• compressing the first stream;
• after compressing the first stream, sending a portion of the first stream to an ejector as a motive fluid to create a suction;
• after compressing the first stream, injecting a remainder of the first stream except the motive fluid into a well;
• sending the second stream to a degassing vessel fluidically connected to the ejector, wherein the suction lowers an internal pressure of the degassing vessel, and at least a portion of the C1-C5 hydrocarbons is released from the second stream as an off-gas;
• mixing the motive fluid and the off-gas in the ejector, forming a two-phase stream;
• and
• sending back the two-phase stream to the GOSP.

A system for treating a produced water (PW) stream, the system comprising:

• a gas oil separation plant (GOSP) to generate a PW stream comprising a dissolved gas;
• a splitter fluidically downstream of the GOSP, configured to split the PW stream into a first stream and a second stream;
• a compressor downstream of the splitter, configured to compress the first stream;
• an ejector downstream of the compressor, configured to receive a portion of the first stream from the compressor, at a motive inlet of the ejector, as a motive fluid to create a suction;
• and
• a degassing vessel downstream of the GOSP and upstream of the ejector, configured to receive the second stream and degas the second stream using the suction, generating an off-gas, wherein the off-gas is sent to a suction inlet of the ejector and mixed with the motive fluid in the ejector.