Will the condensate separated at the natural gas processing plant freeze?
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A certain natural gas processing plant handles 140×104 m3 of gas per day, 45 tons of oil per day, and 7 tons of water per day. The plant uses ethylene glycol injection for anti-freezing purposes, throttling refrigeration, and low-temperature three-phase separation technology. It is necessary to determine whether the condensate oil separated in the low-temperature separator will freeze during transportation through the pipes within the plant to the stabilizer tower; furthermore, it is important to decide whether electric heating strips or insulation materials are required during winter Parameters: Pressure before throttling, Pressure after throttling, Temperature before throttling, Temperature after throttling, Ethylene glycol concentration, Injection volume, Pressure before/after the oil valve in the low-temperature separator for condensate oil: 6.8 MPa, 3.0 MPa; 12 degrees, -12 degrees; 80%, 90–100 l/h; 3.0/0.4 MPa. I have two suggestions: 1) Ethylene glycol has been used for anti-freezing purposes, but most of the ethylene glycol solution has already separated. 2) Condensate oil has a lower freezing point, but it liquefies at -12 degrees; the ambient temperature in winter is -30 degrees.
1# oqya: In fact, there is also a considerable amount of ethylene glycol in the oil phase, which helps to prevent the water contained therein from freezing. As for light oil, it certainly won’t freeze, because it contains no wax.
It won’t freeze; if the landlord is worried, they can take some and do an experiment.
If possible, it’s best to simulate it in Hysys as well. I’m not aware of your specific manufacturing process and more detailed physical property parameters; otherwise, this should be a relatively straightforward simulation.
Because the temperature for low-temperature separation is -12 degrees, while winter temperatures can drop to -30 degrees. So it is possible to freeze. Anti-freezing design is required, such as providing heat tracing for pipelines. 4# Bai Yunfan
First, it is necessary to check whether the condensate contains wax; if it does, the wax deposition point needs to be determined. If there is no wax, then freezing should not occur. With an oil flow rate of 45 tons per day, a level control valve should be used for the oil phase in the low-temperature separator, as light oil will continuously flow through the pipelines. Thirdly, the separation efficiency of ethylene glycol at low temperatures is poor, and light oil contains a large amount of diethanol to prevent it from freezing
6# lipeng20003 won’t freeze; based on practical experience, 1.4 million cubic meters actually required ethylene glycol for dehydration. Heat tracing can cause light hydrocarbons to vaporize. . .
Normal design makes use of heat exchange to recover the coolness of light hydrocarbons, ensuring that their temperature remains at a normal level
It won’t freeze. As the friends mentioned above, at that temperature, most of the ethylene glycol does not separate out, and its aqueous solution does not freeze ； Condensate oil consists of light hydrocarbons, all of which have very low freezing points, so it does not freeze.
What is separated at low temperature should be the condensate, right? As for the issue you mentioned, it depends on the composition of the condensate. What is your subsequent processing step?