Oilfield carbon dioxide flooding wellhead heating and choking system

Abstract

The application discloses an oil field carbon dioxide flooding wellhead heating throttling system, which comprises an electric heating furnace, a primary throttling device and a secondary throttling device; the electric heating furnace is internally provided with a primary heating coil pipe and a secondary heating coil pipe; the primary throttling device is arranged on a primary outlet pipeline; the secondary throttling device is arranged on a secondary outlet pipeline; wellhead medium enters the primary heating coil pipe through a primary inlet pipeline to be subjected to primary heating, is subjected to primary pressure reduction through the primary throttling device, enters the secondary heating coil pipe through a secondary inlet pipeline to be subjected to secondary heating after the primary pressure reduction, and is subjected to secondary pressure reduction through the secondary throttling device. The application solves the problem that, in the prior art, because of the sharp pressure reduction and heat absorption of a large amount of CO2, dry ice freezing and plugging and carried produced water freezing and plugging occur at a carbon dioxide flooding wellhead. The technical effect of safely heating and reducing the pressure of wellhead medium is achieved, and the purpose of saving energy and reducing consumption is achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of carbon dioxide drive wellhead medium heating, in particular to an oilfield carbon dioxide drive wellhead heating throttling system. BACKGROUND

[0002] The carbon dioxide drive enhanced oil recovery technology can not only meet the needs of oilfield development, but also realize geological storage of carbon dioxide, which is of great significance to the protection of atmospheric environment and inhibition of greenhouse effect. With the progress of domestic oilfield development technology, the carbon dioxide miscible phase drive pilot test project is gradually carried out in each oilfield block, and then a series of researches and improvements on the carbon dioxide drive ground gathering and transportation process follow.

[0003] At present, the carbon dioxide drive wellhead mining needs to be depressurized before opening the well, and under certain pressure conditions, a large amount of CO2 will cause dry ice freezing and heat absorption, which will cause freezing and blocking of the pipeline, and freezing and blocking of the produced water due to low temperature to form hydrate. Therefore, unlike the conventional oil and gas well production mode, the carbon dioxide drive wellhead needs to be provided with a heating and throttling pressure reducing device to prevent dry ice and hydrate freezing and blocking. Therefore, an oilfield carbon dioxide drive wellhead heating throttling system is urgently needed. CONTENT OF THE UTILITY MODEL

[0004] The oilfield carbon dioxide drive wellhead heating throttling system provided by the application embodiment solves the problem that a large amount of CO2 will cause dry ice freezing and heat absorption, which will cause freezing and blocking of the carbon dioxide drive wellhead and freezing and blocking of the produced water carried.

[0005] The oilfield carbon dioxide drive wellhead heating throttling system provided by the embodiment of the application comprises an electric heating furnace, a primary throttling device and a secondary throttling device, the electric heating furnace is internally provided with a primary heating coil pipe and a secondary heating coil pipe, the primary heating coil pipe and the secondary heating coil pipe are alternately spirally arranged, an input end of the primary heating coil pipe is in communication with one end of a primary inlet pipeline, an output end of the primary heating coil pipe is in communication with one end of a primary outlet pipeline, the other end of the primary inlet pipeline is connected to the wellhead medium, the other end of the primary outlet pipeline is in communication with one end of a secondary inlet pipeline, an input end of the secondary heating coil pipe is in communication with the other end of the secondary inlet pipeline, and an output end of the secondary heating coil pipe is in communication with a secondary outlet pipeline, the primary throttling device is arranged on the primary outlet pipeline, and the secondary throttling device is arranged on the secondary outlet pipeline, the wellhead medium enters the primary heating coil pipe through the primary inlet pipeline for primary heating, is subjected to primary pressure reduction through the primary throttling device, and is subjected to secondary heating in the secondary heating coil pipe through the secondary inlet pipeline, and is subjected to secondary pressure reduction through the secondary throttling device.

[0006] In a possible implementation, the primary inlet pipeline is provided with an emergency shutdown device.

[0007] In a possible implementation, the electric heater is further provided, a fixed end of the electric heater is arranged on the top of the electric heating furnace, a heating end of the electric heater extends into the electric heating furnace, and the electric heater can heat the heat-conducting medium in the electric heating furnace.

[0008] In a possible implementation, the safety relief device is further provided, the safety relief device is connected to an end of the secondary outlet pipeline away from the electric heating furnace, and the safety relief device is used for discharging the overpressure medium to a designated safety pipeline.

[0009] In a possible implementation, the instrument control cabinet is further provided, temperature transmitters and pressure transmitters are arranged on the primary inlet pipeline, the primary outlet pipeline, the secondary inlet pipeline and the secondary outlet pipeline, and signal output ends of the temperature transmitters and the pressure transmitters are connected to the instrument control cabinet.

[0010] In a possible implementation, the alarm is further provided, and a signal output end of the instrument control cabinet is connected to a signal input end of the alarm.

[0011] In a possible implementation, the over-temperature protection module is further provided, and the over-temperature protection module can automatically cut off the power supply when the heating temperature exceeds a set upper limit of temperature.

[0012] In a possible implementation, the wireless transmission module is further provided, and the wireless transmission module is arranged in the instrument control cabinet.

[0013] In a possible implementation, the explosion-proof power distribution cabinet is further provided, and the explosion-proof power distribution cabinet can provide power for safe operation of the system in an explosion-proof area.

[0014] The one or more technical solutions provided in the application have at least the following technical effects:

[0015] The utility model discloses an oil field carbon dioxide displacement well mouth heating throttling system, including electric heating furnace, primary throttling device and secondary throttling device, be provided with primary heating coil pipe and secondary heating coil pipe in electric heating furnace, primary heating coil pipe and secondary heating coil pipe alternate spiral setting, the input of primary heating coil pipe with one end of primary import pipeline intercommunication, and the output of primary heating coil pipe with one end of primary export pipeline intercommunication, the other end of primary import pipeline passes into well mouth medium, and the other end of primary export pipeline with one end of secondary import pipeline intercommunication, the input of secondary heating coil pipe with the other end of secondary import pipeline intercommunication, and the output of secondary heating coil pipe with secondary export pipeline intercommunication, primary throttling device sets up on primary export pipeline, and secondary throttling device sets up on secondary export pipeline, well mouth medium enters primary heating coil pipe and carries out primary heating through primary import pipeline, and then carries out first pressure reduction through primary throttling device, and the medium after first pressure reduction enters secondary heating coil pipe and carries out secondary heating through secondary import pipeline, and then carries out second pressure reduction through secondary throttling device. Well mouth medium reaches the technical effect of heating and throttling pressure reduction after primary heating, primary throttling, secondary heating and secondary throttling. The application solves the problem that the dry ice freeze blockage and the produced water freeze blockage of carbon dioxide displacement well mouth caused by the sharp pressure reduction and heat absorption of a large amount of CO2 in the prior art. The technical effect of safe heating and pressure reduction of well mouth medium is realized, the purpose of energy saving and consumption reduction is achieved, and the well mouth heating throttling process in the oil field CCUS exploitation is improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical scheme of the utility model embodiment, the following will introduce the drawings needed to be used in the description of the utility model embodiment briefly, and obviously, the drawings in the following description are some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creating labor.

[0017] Figure 1 It is a front view of the oil field carbon dioxide displacement well mouth heating throttling system provided for the embodiment of the application.

[0018] Figure 2 It is a top view of the oil field carbon dioxide displacement well mouth heating throttling system provided for the embodiment of the application.

[0019] Figure: 1-electric heating furnace;2-primary throttling device;3-secondary throttling device;4-primary import pipeline;5-primary export pipeline;6-secondary import pipeline;7-secondary export pipeline;8-emergency shutdown device;9-electric heater;10-safety relief device;11-instrument control cabinet;12-explosion-proof distribution cabinet. DETAILED DESCRIPTION

[0020] Clearly and completely describe the technical scheme in the embodiments of the utility model with the drawings in the embodiments of the utility model, obviously, the described embodiment is a part of the embodiment of the utility model, and is not all the embodiment. Based on the embodiment in the utility model, all other embodiments obtained by the ordinary skill in the art without making creative labor belong to the range of protection of the utility model.

[0021] In the description of the embodiments of the utility model, it needs to be explained that the orientation or position relation indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like is the orientation or position relation shown in the drawings, and is only for the convenience of describing the embodiments of the utility model and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a specific orientation, a specific orientation and operation, and therefore cannot be understood as limiting the utility model. The terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance. In addition, the terms "mounting", "connecting", "connection" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, it can be mechanically connected, or it can be electrically connected, it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication between two elements. For the ordinary skill in the art, the specific meaning of the above terms in the embodiments of the utility model can be understood according to the specific circumstances.

[0022] The utility model embodiment provides a kind of oil field carbon dioxide displacement wellhead heating throttling system, as shown in figure Figures 1-2 It is shown that it includes electric heating furnace 1, primary throttling device 2 and secondary throttling device 3;Electric heating furnace 1 is provided with primary heating coil pipe and secondary heating coil pipe;Primary heating coil pipe and secondary heating coil pipe are alternately coiled;The input end of primary heating coil pipe is communicated with one end of primary inlet pipeline 4, and the output end of primary heating coil pipe is communicated with one end of primary outlet pipeline 5;The other end of primary inlet pipeline 4 is communicated with wellhead medium;The other end of primary outlet pipeline 5 is communicated with one end of secondary inlet pipeline 6;The input end of secondary heating coil pipe is communicated with the other end of secondary inlet pipeline 6, and the output end of secondary heating coil pipe is communicated with secondary outlet pipeline 7;Primary throttling device 2 is arranged on primary outlet pipeline 5;Secondary throttling device 3 is arranged on secondary outlet pipeline 7;Wellhead medium enters primary heating coil pipe and carries out primary heating by primary inlet pipeline 4, and then carries out primary pressure reduction by primary throttling device 2, and the medium after primary pressure reduction enters secondary heating coil pipe and carries out secondary heating by secondary inlet pipeline 6, and then carries out secondary pressure reduction by secondary throttling device 3.

[0023] Exemplarily, the material of the first inlet pipeline 4, the first outlet pipeline 5, the second inlet pipeline 6 and the second outlet pipeline 7 is stainless steel.

[0024] Exemplarily, the first heating coil and the second heating coil are alternately arranged in a spiral form.

[0025] Exemplarily, the present application adopts indirect heating, the electric heater 9 heats the heat-conducting medium in the electric heating furnace 1, and then the heat-conducting medium is uniformly heated by the first heating coil and the second heating coil. The indirect heating mode avoids local overheating and coking, and reduces the leakage risk of direct heating of high-pressure medium.

[0026] Exemplarily, the intermediate pipeline is further included, the first throttling device 2 is in communication with the second throttling device 3 through the intermediate pipeline, and the second inlet pipeline 6 and the intermediate pipeline are both provided with valves. When the temperature of the wellhead medium reaches the preset temperature value after passing through the first heating coil and the first throttling device 2, the wellhead medium after passing through the first throttling device 2 can be directly transported to the second throttling device 3 through the intermediate pipeline, specifically, the wellhead medium is heated after passing through the first heating coil, and then is subjected to primary pressure reduction through the first throttling device 2. If the temperature meets the temperature requirement of the final outlet, the valve on the second inlet pipeline 6 is closed, the valve on the intermediate pipeline is opened, and the wellhead medium can be directly transported to the second throttling device 3 through the intermediate pipeline for secondary pressure reduction and then output.

[0027] The wellhead medium of the present application is a multiphase mixed fluid from a carbon dioxide flooding wellhead, which mainly contains supercritical or liquid carbon dioxide, crude oil and formation water.

[0028] Exemplarily, the first throttling is located after the first heating, which can perform primary pressure reduction. The second throttling is located after the second heating, which can perform accurate pressure reduction, so that the outlet pressure meets the technical requirement.

[0029] In the embodiment of the present application, as shown in Figures 1-2 The emergency shutdown device 8 is arranged on the first inlet pipeline 4.

[0030] Exemplarily, the emergency shutdown device 8 can quickly cut off the inlet when the pressure is too high or the process is abnormal, so as to ensure the safety of the system.

[0031] In the embodiment of the present application, as shown in Figures 1-2 The electric heater 9 is further included; the fixed end of the electric heater 9 is arranged at the top of the electric heating furnace 1, the heating end of the electric heater 9 extends into the electric heating furnace 1, and the electric heater 9 can heat the heat-conducting medium in the electric heating furnace 1.

[0032] In the embodiment of the present application, as shown in Figures 1-2As shown, it also includes a safety relief device 10; the safety relief device 10 is connected to the end of the secondary outlet pipeline 7 away from the electric heating furnace 1, and the safety relief device 10 is used to release the overpressure medium to a designated safety pipeline.

[0033] For example, when the system is overpressurized, the safety relief device 10 can release the overpressurized medium to a safety line.

[0034] In the embodiments of this application, such as Figures 1-2 As shown, it also includes an instrument control cabinet 11; temperature transmitters and pressure transmitters are installed on the primary inlet pipe 4, the primary outlet pipe 5, the secondary inlet pipe 6, and the secondary outlet pipe 7; the signal output terminals of the temperature transmitters and the pressure transmitters are connected to the instrument control cabinet 11.

[0035] For example, the instrument control cabinet 11 collects temperature and pressure signals from each detection point and interlocks the opening degree of the primary throttling device 2, the opening degree of the secondary throttling device 3, and the load of the electric heater 9, thereby achieving precise control of the final outlet temperature and final outlet pressure.

[0036] In the embodiments of this application, such as Figures 1-2 As shown, it also includes an alarm; the signal output terminal of the instrument control cabinet 11 is connected to the signal input terminal of the alarm.

[0037] In the embodiments of this application, such as Figures 1-2 As shown, it also includes an over-temperature protection module; when the heating temperature exceeds the set upper temperature limit, the over-temperature protection module can automatically cut off the power supply.

[0038] In the embodiments of this application, such as Figures 1-2 As shown, it also includes a wireless transmission module; the instrument control cabinet 11 is equipped with a wireless transmission module.

[0039] In the embodiments of this application, such as Figures 1-2 As shown, it also includes an explosion-proof distribution cabinet 12; the explosion-proof distribution cabinet 12 can provide power for the safe operation of the system in the explosion-proof area.

[0040] For example, the temperature and pressure transmitters can monitor the temperature and pressure before and after the two-stage heating and throttling in real time. The electric heating furnace 1 is also equipped with a level transmitter and a temperature transmitter. By monitoring the temperature and pressure data, the system achieves interlocked control, thereby automatically adjusting the operating opening of the first and second throttling devices. It can also adjust the operating load of the electric heater 9, ensuring that the wellhead medium meets the technical requirements for final outlet temperature and final outlet pressure. This achieves safe heating and effective pressure reduction of the wellhead medium.

[0041] Exemplarily, the system is provided with an alarm function, and a wireless transmission module is arranged in the instrument control cabinet 11, which is used for remotely transmitting system operation data to the central control room, so as to realize remote monitoring.

[0042] Exemplarily, by the alternating operation of two-stage heating and two-stage throttling, the application can effectively prevent the freezing problem caused by the sharp drop of medium temperature due to heat absorption in the throttling process. The application adopts an indirect heating method and is provided with multiple safety designs such as an emergency shutdown device 8, a safety relief device 10 and an over-temperature protection module, and is particularly suitable for high-pressure dangerous wellhead environments. Further, based on the automatic feedback regulation of the PLC or similar control system, the application reduces manual intervention and enables the system to run smoothly, thereby reducing management costs. Through precise temperature and pressure control, the application avoids energy waste and has higher energy efficiency than traditional heating methods.

[0043] Exemplarily, the process system of the application fills the gap of special heating and throttling devices for carbon dioxide drive wellheads, and perfects the ground process chain of CCUS mining. The two-stage heating and throttling technology proposed by the application realizes safe heating and effective pressure reduction of the wellhead medium, and compared with the traditional heating method, the application achieves the purpose of energy saving and consumption reduction.

[0044] The various embodiments in the specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment mainly explains the difference from other embodiments.

[0045] The above examples are only used to illustrate the technical solutions of the application, and are not limited to the application; although the application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the application.

Claims

1. An oilfield carbon dioxide flooding wellhead heating and choking system, characterized in that, It comprises an electric heating furnace (1), a primary throttling device (2) and a secondary throttling device (3). The electric heating furnace (1) is provided with a primary heating coil and a secondary heating coil; the primary heating coil and the secondary heating coil are alternately arranged in a coil shape. The input end of the primary heating coil is communicated with one end of a primary inlet pipeline (4), and the output end of the primary heating coil is communicated with one end of a primary outlet pipeline (5). The other end of the primary inlet pipeline (4) is communicated with the wellhead medium. The other end of the primary outlet pipeline (5) is communicated with one end of a secondary inlet pipeline (6). The input end of the secondary heating coil is communicated with the other end of the secondary inlet pipeline (6), and the output end of the secondary heating coil is communicated with a secondary outlet pipeline (7). The primary throttling device (2) is arranged on the primary outlet pipeline (5). The secondary throttling device (3) is arranged on the secondary outlet pipeline (7). The wellhead medium enters the primary heating coil through the primary inlet pipeline (4) for primary heating, is subjected to primary pressure reduction through the primary throttling device (2), enters the secondary heating coil through the secondary inlet pipeline (6) for secondary heating, and is subjected to secondary pressure reduction through the secondary throttling device (3).

2. The oilfield carbon dioxide flood wellhead heating and choking system of claim 1, wherein, An emergency shutdown device (8) is arranged on the primary inlet pipeline (4).

3. The oilfield carbon dioxide flood wellhead heating and choking system of claim 1, wherein, It further comprises an electric heater (9). The fixed end of the electric heater (9) is arranged on the top of the electric heating furnace (1), the heating end of the electric heater (9) extends into the electric heating furnace (1), and the electric heater (9) can heat the heat-conducting medium in the electric heating furnace (1).

4. The oilfield carbon dioxide flood wellhead heating and choking system of claim 1, wherein, It further comprises a safety relief device (10). The safety relief device (10) is connected to the end of the secondary outlet pipeline (7) away from the electric heating furnace (1), and is used for discharging overpressure medium to a designated safety pipeline.

5. The oilfield carbon dioxide flood wellhead heating and choking system of claim 1, wherein, It further comprises an instrument control cabinet (11). Temperature transmitters and pressure transmitters are arranged on the primary inlet pipeline (4), the primary outlet pipeline (5), the secondary inlet pipeline (6) and the secondary outlet pipeline (7). The signal output ends of the temperature transmitters and the signal output ends of the pressure transmitters are connected to the instrument control cabinet (11).

6. The oilfield carbon dioxide flood wellhead heating and choking system of claim 5, wherein, It further comprises an alarm. The signal output end of the instrument control cabinet (11) is connected to the signal input end of the alarm.

7. The oilfield carbon dioxide flood wellhead heating and choking system of claim 1, wherein, It further comprises an over-temperature protection module. When the heating temperature exceeds the set upper limit, the over-temperature protection module can automatically cut off the power supply.

8. The oilfield carbon dioxide flood wellhead heating and choking system of claim 5, wherein, It further comprises a wireless transmission module. The wireless transmission module is arranged in the instrument control cabinet (11).

9. The oilfield carbon dioxide flood wellhead heating and choking system of claim 1, wherein, It further comprises an explosion-proof power distribution cabinet (12). The explosion-proof power distribution cabinet (12) can provide power for the safe operation of the system in the explosion-proof area.

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