CN-118835980-B - Collecting device for condensate wellhead

CN118835980BCN 118835980 BCN118835980 BCN 118835980BCN-118835980-B

Abstract

The invention provides a collecting device for a condensate wellhead, which comprises a production mechanism, a collecting mechanism and a reinjection mechanism, wherein the production mechanism comprises an oil pipe which is arranged in a casing and is used for receiving fluid from the condensate wellhead, the collecting mechanism comprises a separating assembly which is connected with the oil pipe, a collector which is arranged below the separating assembly, and the reinjection mechanism comprises a first pipeline which is arranged between the separating assembly and the casing, wherein the fluid can be subjected to gas-liquid separation under the action of the separating assembly, a separated liquid phase enters the collector, a separated first part of gas phase flows to an annulus between the oil pipe and the casing through the first pipeline, and a second part of gas phase flows to the outside through a second pipeline. The invention ensures that the fluid from the condensate wellhead is sufficiently separated to increase the yield of condensate.

Inventors

HE JIAYUAN
LI XIAOLONG
ZHANG LUFENG
WANG HAIBO
YANG KEFENG

Assignees

中国石油化工股份有限公司
中国石油化工股份有限公司石油勘探开发研究院

Dates

Publication Date: 20260508
Application Date: 20230423

Claims (5)

1. A collection device for a condensate wellhead, comprising: Production mechanism comprising an oil pipe (12) arranged in a casing (11) and adapted to receive fluid from a condensate wellhead, and A collecting mechanism comprising a separating assembly connected to the oil pipe (12), and a collector (4) arranged below the separating assembly, and A reinjection mechanism comprising a first line (5) arranged between the separation assembly and the casing (11), Wherein the fluid is capable of gas-liquid separation under the action of the separation assembly, the separated liquid phase enters the collector (4), a first part of the separated gas phase flows to an annulus (101) between the oil pipe (12) and the sleeve (11) through the first pipeline (5), a second part flows to the outside through the second pipeline (6), the collecting device further comprises a packer (102) arranged between the sleeve (11) and the oil pipe (12) and positioned below the gas lift valve (7), the reinjection mechanism further comprises a gas booster (51) arranged on the first pipeline (5), the mining mechanism further comprises a gas lift valve (7) arranged at an inlet end (121) of the oil pipe (12), and a sensor arranged on the gas lift valve (7), the collecting device further comprises a middle control platform (8) connected with the sensor, and the middle control platform (8) can perform real-time pressure value in the oil pipe (12) so as to ensure that more liquid phase can enter the collector (4), The center console (8) is configured to enable the gas phase separated by the separation assembly to flow back into the oil pipe (12) through the gas booster (51), the annular space (101) and the gas lift valve (7) in sequence when the pressure value detected by the sensor is smaller than a critical pressure value, enable the gas phase separated by the separation assembly to flow to the outside through the second pipeline (6) when the pressure value detected by the sensor is larger than or equal to the critical pressure value, increase the pressure in the oil pipe (12) by reinjection of the separation gas, thereby reducing the precipitation amount of the liquid phase in the oil pipe (12) and improving the collection amount of the liquid phase by the collector (4), The separation assembly further comprises a second separator (3) for receiving fluid from the first separator (2), the second separator (3) is communicated with the first separator (2), the volume of the first separator (2) is smaller than that of the second separator (3), the gas booster (51) is arranged at one end, far away from the first separator (2), of the second separator (3), the collecting device further comprises an oil gas analysis sensor (81) arranged on the first pipeline (5) and the second pipeline (6), and the center console (8) is connected with the oil gas analysis sensor (81).
2. A collecting device for condensate wellheads according to claim 1, wherein the separation assembly comprises a first separator (2) connected to the outlet end (122) of the oil pipe (12), a number of first support seats (21) configured as strips being provided below the first separator (2).
3. A collecting device for condensate wellheads according to claim 2, wherein the first separator (2) comprises a body part (201) configured in the form of a square, on both sides of the body part (201) there being through holes (22), which through holes (22) are axially located at two-thirds to three-quarters of the body part (201).
4. A collecting device for condensate wellheads according to claim 3, wherein the separation assembly further comprises a number of second supporting seats (31) configured as blocks, circumferentially equidistant at the bottom of the second separator (3), wherein the first line (5) and the second line (6) both communicate with the second separator (3).
5. The collecting device for condensate wellheads according to claim 4, further comprising a single flow valve (9) arranged between the collector (4) and the first separator (2) and the second separator (3), respectively.

Description

Collecting device for condensate wellhead Technical Field The invention relates to the field of wellhead equipment for oil and gas field development, in particular to a collecting device for condensate wellhead. Background Condensate reservoirs are a special type of gas reservoir, which is a gaseous reservoir formed under specific geological conditions. Condensate gas typically exhibits gaseous characteristics under reservoir conditions, and as the formation pressure drops to dew point pressure, the condensate gas undergoes an anti-condensate effect to produce condensate. Therefore, condensate may be separated out from both the reservoir and the surface during condensate reservoir development. In general, condensate precipitated in the formation adheres to the rock surface in the form of an oil film and is difficult to extract and lost in the formation. Therefore, there is a need for condensate reservoirs with higher condensate content to prevent an excessively rapid drop in formation pressure to avoid loss in the formation after substantial condensate precipitation. At present, a condensate gas well is not provided with a special device at a wellhead, and is usually connected into a pipeline and then directly put into the station or is provided with a simple gas-liquid separation device at the ground surface, so that condensate gas is connected into the pipeline and put into the station to collect condensate gas. For example, CN212837714U discloses an automatic recovery device for condensate in well group associated gas flow, comprising a pry seat, wherein a PLC and a liquid separation bag are arranged on the pry seat, an inlet of the liquid separation bag is connected with an associated gas inlet pipeline, an outlet of the liquid separation bag is connected with an associated gas outlet pipeline and a condensate outlet pipeline, an electromagnetic valve, a diaphragm pump and a check valve are installed on the condensate outlet pipeline, a floating ball liquid level meter is inserted in the liquid separation bag, and the floating ball liquid level meter, the electromagnetic valve and the diaphragm pump are respectively and electrically connected with the PLC. When the liquid level reaches the upper liquid level, the PLC starts the electromagnetic valve, starts the diaphragm pump, reinjects condensate oil to the annular space of the oil well oil sleeve, when the liquid level of the liquid separation bag drops to the lower liquid level, the diaphragm pump stops running, the electromagnetic valve is closed, the PLC records the discharge times, and the production quantity is calculated. The device can not adjust the formation pressure, so that a great amount of condensate is easily caused to be lost in the formation after being separated out. It is therefore desirable in the art to provide a collection device for condensate wellhead to address the above-mentioned problems. Disclosure of Invention The object of the present invention is to propose a collecting device for condensate wellhead in a two-stage separation (first separator and second separator) way, ensuring that the fluid coming from the condensate wellhead can be separated sufficiently to increase the yield of condensate. According to the present invention there is provided a collection device for a condensate wellhead comprising a production mechanism comprising tubing disposed within a casing and adapted to receive fluid from the condensate wellhead, and A collecting mechanism comprising a separating assembly connected with the oil pipe, a collector arranged below the separating assembly, and A reinjection mechanism comprising a first line disposed between the separation assembly and the cannula, The gas-liquid separation device comprises a separation assembly, a collector, a first pipeline, a second pipeline, a casing, a gas pipe, a gas-liquid separation device and a gas-liquid separation device, wherein the gas-liquid separation can be carried out under the action of the separation assembly, the separated liquid phase enters the collector, a first part of separated gas phase flows to an annulus between the oil pipe and the casing through the first pipeline, and a second part of separated gas phase flows to the outside through the second pipeline. In one embodiment, the reinjection mechanism further comprises a gas booster disposed on the first line. In one embodiment, the production mechanism further comprises a gas lift valve disposed at the inlet end of the tubing, and a sensor disposed on the gas lift valve. In one embodiment, the collection device further comprises a center console coupled to the sensor, the center console configured to: When the pressure value detected by the sensor is smaller than a critical pressure value, enabling gas phases separated by the separation assembly to flow back into the oil pipe through the gas booster, the annular space and the gas lift valve in sequence; And when the pressure value detected by the sensor is