Oil removal process for produced gas of underground gas storage with high condensate oil content

Abstract

The invention relates to a process for removing oil from produced gas of an underground gas storage with high condensate oil content, which comprises the following steps: heating the produced gas to 74-76 DEG C, carrying out primary throttling, introducing the throttled produced gas into a three-phase separator, and carrying out oil-gas-water three-phase separation to obtain a first gas phase, the oil phase separated by the three-phase separator is subjected to secondary throttling to 0.3 MPa and then enters a flash separator for oil-water separation to obtain a second gas phase, and the dehydrated first gas phase and the pressurized second gas phase are converged and then introduced into a gas source pipe network; according to the process, a secondary throttling process is adopted for the produced gas, gas condensate separation is carried out in two times, 98% of gas-liquid separation can be achieved by controlling the pressure to be 10 MPa through primary throttling, about 2% of the remaining produced gas is subjected to secondary throttling to be 0.3 MPa and then is subjected to flash evaporation, and natural gas is thoroughly separated from gas condensate; 98% of produced gas does not need to be pressurized again, on one hand, it is guaranteed that pressure can be fully utilized, energy consumption is greatly reduced, on the other hand, the overall project investment can be reduced, and energy conservation and consumption reduction are achieved.

Description

technical field [0001] The invention belongs to the technical field of condensate oil removal, and in particular relates to a process for removing oil from gas produced in an underground gas storage with high condensate oil content. Background technique [0002] The underground gas storage with high condensate content is a gas storage formed by the use of depleted oil and gas reservoirs. The main feature of this type of gas storage is that the produced gas (also called associated gas) contains a large amount of condensate oil and even crude oil. The treatment of the produced natural gas is the key to this kind of gas storage. In order to ensure the normal operation of subsequent pipelines, production equipment and instruments, it is necessary to remove saturated water, condensate oil, dust and sediment and other impurities in the produced gas. At present, most of these gas storages adopt the following oil production processes: [0003] Gas well Xmas tree → wellhead throttli...

AI Technical Summary

Problems solved by technology

[0004] This type of gathering and transportation process adopts a first-stage throttling treatment process to flash all the associated gas in the condensate oil, but this process requires additional associated gas treatment devices (including molecular sieve dehydration, auxiliary refrigeration dehydrocarbons, and liquefied gas treatment devices) And gas secondary pressurization device (raw material gas booster unit)

Although it can realize the treatment of associated gas, meet the requirements of water dew point and hydrocarbon dew point, and separate liquefied gas from light hydrocarbons at the same time, the pressure energy of this process is not fully utilized, and it needs a second pressurization for external transportation, and the additional energy consumption is high.

At the same time, the molecular sieve dehydration process has high energy consumption, high investment, huge processing equipment or multi-row processing devices

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