CN-121993119-A - Air foam flooding oil extraction well site safety protection system and method

Abstract

The invention discloses an air foam flooding oil extraction well site safety protection system which comprises a plurality of benefited oil extraction well heads and non-benefited oil extraction well heads, wherein the benefited oil extraction well heads and the non-benefited oil extraction well heads are respectively connected with an oil pipe oil outlet pipeline and a sleeve gas outlet pipeline, the sleeve gas outlet pipeline is respectively connected with a sleeve gas conveying pipeline, the sleeve gas conveying pipeline and the oil pipe oil outlet pipeline are converged to an oil-gas mixed conveying pipeline, the oil-gas mixed conveying pipeline is connected with an automatic ball throwing and collecting device, the pipe gas conveying pipeline is connected with an oxygen content on-line monitoring device, an SSNR oil pumping unit linkage control device is arranged in an oil pumping unit, and the SSNR oil pumping unit linkage control device is connected with a PIA digital control system. The invention also discloses a safety protection method for the air foam flooding oil extraction well site. The air foam flooding oil extraction well site safety protection system and method disclosed by the invention solve the problems that overpressure is caused by air channeling of an oil extraction well which benefits after air foam flooding, oxygen content is not monitored timely, and a large safety risk is generated.

Inventors

• XIONG XIAOWEI
• YIN RAN
• WANG ZHI
• FENG YU
• HUO FUYONG
• WANG CHANGYAO
• BAI JIANFENG
• WANG HAN
• MA YONG
• ZHANG QIAOSHENG

Assignees

• 长庆工程设计有限公司
• 中国石油天然气集团有限公司

Dates

Publication Date

20260508

Application Date

20241101

Claims (9)

1. 1. The air foam flooding oil extraction well site safety protection system is characterized by comprising a plurality of benefited oil extraction well heads (1) and non-benefited oil extraction well heads (2), wherein the benefited oil extraction well heads (1) and the non-benefited oil extraction well heads (2) are respectively connected with oil pipe oil outlet pipelines (23) and casing gas outlet pipelines (25), the casing gas outlet pipelines (25) are respectively connected with a first casing gas conveying pipeline (3) and a second casing gas conveying pipeline (8), the first casing gas conveying pipeline (3) and the oil pipe oil outlet pipelines (23) are converged to an oil-gas mixed conveying pipeline (5), the oil-gas mixed conveying pipeline (5) is connected with an automatic ball throwing device (6), the two second casing gas conveying pipelines (8) are jointly connected with an oxygen content online monitoring device (9), the benefited oil extraction well heads (1) and the non-benefited oil extraction well heads (2) are respectively connected with an oil pumping unit (24), an SSNR oil pumping unit linkage control device (10) is arranged in the oil pumping unit (24), and the oxygen content online monitoring device (9) and the SSNR linkage control device (10) are respectively connected with a PIA digital control system (20) through a signal transmission line (16).
2. 2. The air foam flooding oil extraction well site safety protection system according to claim 1, wherein a plurality of first casing gas conveying pipelines (3) are respectively provided with a constant pressure air release valve (4), the PIA digital control system (20) comprises a well site RTU and a station control system, and the oxygen content online monitoring device (9) and the SSNR pumping unit linkage control device (10) are respectively connected with the well site RTU and the station control system through signal transmission lines (16).
3. 3. The air foam flooding oil well site safety protection system according to claim 2, wherein a plurality of oil pipe oil outlet pipelines (23) connected with the benefited oil well heads (1) are respectively provided with a first electric valve (7), the first electric valves (7) are respectively connected with a first electric actuator (17), and the first electric actuators (17) are respectively connected with a well site RTU and a station control system through signal transmission lines (16).
4. 4. The air foam flooding oil production well site safety protection system according to claim 3, wherein a plurality of casing gas outlet pipelines (25) connected with the benefited oil production well heads (1) are respectively provided with a second electric valve (13), the plurality of second electric valves (13) are respectively connected with a second electric actuator (18), and the second electric actuators (18) are respectively connected with a well site RTU and a station control system through signal transmission lines (16).
5. 5. The air foam flooding oil well site safety protection system according to claim 4, wherein a plurality of oil pipe oil outlet pipelines (23) connected with the benefit oil well heads (1) are respectively connected with first PT pressure transmitters (11), casing gas outlet pipelines (25) connected with the benefit oil well heads (1) are respectively connected with second PT pressure transmitters (14), and the first PT pressure transmitters (11) and the second PT pressure transmitters (14) are respectively connected with a well site RTU and a station control system through signal transmission lines (16).
6. 6. The air foam flooding oil well site safety protection system according to claim 5, wherein any one of the second casing gas conveying pipelines (8) is connected with a third electric valve (15) close to the oxygen content on-line monitoring device (9), the third electric valve (15) is connected with a third electric actuator (19), the other second casing gas conveying pipeline (8) is connected with a fourth electric valve (21) close to the oxygen content on-line monitoring device (9), the third electric valve (15) is connected with the third electric actuator (19), the fourth electric valve (21) is connected with a fourth electric actuator (22), and the third electric actuator (19) and the fourth electric actuator (22) are connected with a well site RTU and a station control system through signal transmission lines (16) respectively.
7. 7. The well site safety protection method is characterized by comprising the following specific steps of: S1, when an oil well is produced normally, sleeve gas is converged into an oil pipe oil outlet pipeline (23) through a sleeve gas outlet pipeline (25) and a constant pressure air release valve (4) and is mixed with produced crude oil to be conveyed to a downstream station, and when the oil well generates gas channeling, the sleeve gas enters S2; S2, when gas channeling occurs in the oil well, the oxygen content on-line monitoring device (9) transmits the oxygen content value to a station control system in the PIA digital control system (20) and gives an alarm, and after the gas channeling risk is eliminated, the oil pumping unit is restarted to produce crude oil.
8. 8. The method for protecting well site safety according to claim 7, wherein S1 is specifically that during normal production of a benefited oil well or a non-benefited oil well, associated gas in the oil well is mixed with water-containing oil at the outlet of an oil pipe oil outlet pipeline (23) after passing through a first casing gas conveying pipeline (3) and a constant pressure relief valve (4) from a casing gas outlet pipeline (25), enters an oil-gas mixing pipeline (5) and finally enters a downstream station after passing through an automatic ball feeding and collecting device (6).
9. 9. The method of claim 8, wherein S2 is specifically that when gas channeling occurs in the oil well, the oxygen content on-line monitoring device (9) transmits an oxygen content value to the station control system and gives an alarm, the well site RTU sends an execution signal to the electric actuator and SSZR pumping unit linkage control device (10), the first electric valve (7) and the second electric valve (13) are closed, meanwhile, the well site RTU sends a stop signal to the SSZR pumping unit linkage control device (10) to close the pumping unit (24), and after the gas channeling risk is eliminated, the pumping unit is restarted for production.

Description

Air foam flooding oil extraction well site safety protection system and method Technical Field The invention belongs to the field of oil and gas gathering and transportation engineering in petroleum industry, relates to an air foam flooding oil extraction well site safety protection system and also relates to a well site safety protection method. Background The air foam flooding technology for improving recovery ratio organically combines air injection flooding with foam flooding, and uses foam as profile control agent and air as oil displacement agent, so that the problem of water content rise greatly caused by pure water injection can be avoided, and the oil yield of a single well can be improved, thereby having stronger practical application value. After the low-permeability oil reservoir of the Changqing oil field is subjected to air foam flooding, the pressure level of the oil reservoir is increased, and the development effect is obviously improved. Because of the micro-cracks in the formation, after a period of time of air foam flooding, premature breakthrough of gas and risk of gas channeling may occur in the fracture-oriented well. After gas channeling occurs, wellhead pressure may gradually rise, and the problem of injury or explosion caused by overpressure leakage of the oil extraction wellhead may also be caused. On the other hand, although the medium injected by the air foam flooding is oxygen-reduced air, the dissolved oxygen carried into the oil reservoir by the injected water slug during the foam liquid preparation cannot be avoided to be accumulated in the stratum, and the beneficial oil well associated gas may contain a certain amount of oxygen, so that fire or explosion can be caused when the oxygen concentration exceeds the standard. The safety risk is high in both cases. There may be an unequal number of air foam flooding benefited oil recovery wells and non-benefited oil recovery wells at the production well site. The benefit wells all have a risk of gas channeling over pressure. Disclosure of Invention The first object of the invention is to provide an air foam flooding well site safety protection system, which solves the problem that overpressure is caused by gas channeling of a benefited oil production well after air foam flooding, and oxygen content is not monitored timely. A second object of the present invention is to provide a well site safety protection method. The first technical scheme adopted by the invention is an air foam flooding oil extraction well site safety protection system, which comprises a plurality of benefited oil extraction well heads and non-benefited oil extraction well heads, wherein the benefited oil extraction well heads and the non-benefited oil extraction well heads are respectively connected with an oil pipe oil outlet pipeline and a sleeve gas outlet pipeline, the sleeve gas outlet pipeline is respectively connected with a first sleeve gas conveying pipeline and a second sleeve gas conveying pipeline, the first sleeve gas conveying pipeline and the oil pipe oil outlet pipeline are converged to an oil-gas mixed conveying pipeline, the oil-gas mixed conveying pipeline is connected with an automatic ball throwing device, the two second sleeve gas conveying pipelines are commonly connected with an oxygen content on-line monitoring device, the benefited oil extraction well heads and the non-benefited oil extraction well heads are respectively connected with an oil pumping unit, an SSNR (single-input-output) linkage control device is arranged in the oil pumping unit, and the oxygen content on-line monitoring device and the SSNR oil pumping unit linkage control device are respectively connected with a PIA digital control system through signal transmission lines. The first aspect of the present invention is also characterized in that, And the PIA digital control system comprises a well site RTU and a station control system, and the oxygen content online monitoring device and the SSNR pumping unit linkage control device are respectively connected with the well site RTU and the station control system through signal transmission lines. And the oil pipe outlet pipelines connected with the plurality of benefited oil extraction wellheads are respectively provided with a first electric valve, the first electric valves are respectively connected with a first electric actuator, and the first electric actuators are respectively connected with the wellsite RTU and the station control system through signal transmission lines. And a plurality of casing gas outlet pipelines connected with the benefited oil extraction well heads are respectively provided with a second electric valve, the second electric valves are respectively connected with a second electric actuator, and the second electric actuators are respectively connected with the well site RTU and the station control system through signal transmission lines. The oil pipe delivery pipelines connected with the plurality