Offshore platform flare gas ignition system and flare ignition control method

Abstract

The application discloses a marine platform flare gas ignition system and a flare ignition control method. The flare system comprises a flare ignition system, a flame detector, a first flare gas burner and a control system. The flare ignition system is used for igniting the flare gas passing through the first flare gas burner. The flame detector is used for detecting the flame state of the flare gas burned by the first flare gas burner. The control system controls the start and stop of the flare ignition system according to the on-off state of the first flare gas burner and the flame state detected by the flame detector. The function of judging whether the flare gas is normally burned according to whether the first flare gas burner is in the on-off state, whether the flare gas passes through and whether the flame exists in the on state is realized. The automatic ignition of the flare gas and the automatic monitoring function in various cases are realized. The problem of a large amount of flare gas maintaining a long-lasting light and purge gas is solved. The green, low-carbon and safe emission of the flare gas of the marine platform is achieved.

Description

Technical Field

[0001] This invention relates to the field of offshore oil and gas field production technology, and in particular to an offshore platform flare gas ignition system and flare ignition control method. Background Technology

[0002] Flare systems are crucial safety facilities in offshore oil and gas field production. They guide associated gas, low-pressure separation flash vapor, process equipment sealing gas, and flare gas from platform facilities during normal production processes to the flare head for combustion and emission, ensuring platform safety. This flare gas combustion emission system requires purge gas and a continuous flame to ensure timely ignition of the flare gas and a slight positive pressure seal at the flare head. The continuous flame and purge gas consume approximately 1000 standard cubic meters of fuel gas daily; this consumption increases significantly during extreme weather conditions such as strong winds. This emission method wastes resources and causes environmental pollution.

[0003] Therefore, there is an urgent need for a new offshore platform flare gas ignition system and flare ignition control method to solve the above-mentioned technical problems. Summary of the Invention

[0004] The present invention aims to solve the above-mentioned technical problems, namely, that the existing flare gas combustion emission system requires the installation of purge gas and a continuous lamp to ensure timely ignition of the flare gas and micro-positive pressure sealing of the flare head. The continuous lamp and purge gas require a large amount of gas consumption per day. This emission method causes waste of resources and environmental pollution.

[0005] To this end, in a first aspect, the present invention provides a flare gas ignition system for offshore platforms, the flare system comprising a flare ignition system, a flame detector, a first flare gas burner, and a control system, wherein the first flare gas burner is used to pass flare gas, the flare ignition system is used to ignite the flare gas passing through the first flare gas burner, the flame detector is used to detect the flame state of the flare gas burning in the first flare gas burner, the flare ignition system, the flame detector, and the first flare gas burner are all communicatively connected to the control system, and the control system controls the start-up and shutdown of the flare ignition system according to the on / off state of the first flare gas burner and the flame state detected by the flame detector.

[0006] In a specific embodiment of the above-mentioned offshore platform flare gas ignition system, when the control system detects that the switch state of the first flare gas burner has changed from closed to open, the control system controls the flare ignition system to start ignition; and / or

[0007] When the control system detects that the first flare gas burner is in the open state and the flame detector does not detect a combustion flame, the control system controls the flare ignition system to start continuous ignition.

[0008] In a specific implementation of the above-mentioned offshore platform flare gas ignition system, when the control system detects that the first flare gas burner is in a closed state or the flame detector detects the presence of a combustion flame, the control system controls the flare ignition system to shut down.

[0009] In a specific embodiment of the above-mentioned offshore platform flare gas ignition system, the flare system further includes a second flare gas burner, which is normally open. There are at least three first flare gas burners, which are evenly distributed around the second flare gas burner in a circumferential arrangement. Each first flare gas burner is matched with a flare ignition system and a flame detector.

[0010] In a specific embodiment of the above-mentioned offshore platform flare gas ignition system, the flare system further includes a flare distribution tank, a flare arm, and a flare gas main pipe. The inlet of the flare distribution tank is connected to the flare gas main pipe, and the outlet of the flare distribution tank is connected to the inlet of the flare arm. The first flare gas burner and the second flare gas burner are both installed at the top of the flare arm and connected to its outlet. A pressure detector is installed on the flare distribution tank. The pressure detector is communicatively connected to the control system. The control system controls the opening and closing of the first flare gas burner and the start and stop of the flare ignition system based on the pressure information sent by the pressure detector.

[0011] In a specific embodiment of the above-mentioned offshore platform flare gas ignition system, the flare system further includes a micro-positive pressure maintenance system. The micro-positive pressure maintenance system includes a gas source delivery pipeline, one end of which is connected to a micro-positive pressure gas source, and the other end of which is connected to the flare gas main pipe. A micro-positive pressure regulating valve is installed on the gas source delivery pipeline, and the micro-positive pressure regulating valve is communicatively connected to the control system.

[0012] In a specific embodiment of the above-mentioned offshore platform flare gas ignition system, the flare ignition system includes an ignition device and an ignition device status detector. The ignition device is used to ignite the flare gas, and the ignition device status detector is used to detect the working status of the ignition device. Both the ignition device status detector and the ignition device are communicatively connected to the control system.

[0013] In a second aspect, the present invention also provides a flare ignition control method for a random ignition system for flare gas on an offshore platform. The random ignition system includes a first flare gas burner, a flare ignition system, and a control system. The first flare gas burner is used to pass flare gas, and the flare ignition system is used to ignite the flare gas passing through the first flare gas burner. Both the first flare gas burner and the flare ignition system are communicatively connected to the control system. The flare ignition control method includes:

[0014] Determine the on / off status of the first flare gas burner;

[0015] If the switch state of the first flare gas burner changes from closed to open, the control system controls the flare ignition system to start ignition.

[0016] Determine the flame state of the first flare gas burner;

[0017] If there is a combustion flame at the first flare gas burner or the first flare gas burner is in a closed state, the control system controls the flare ignition system to shut down the ignition.

[0018] In a specific embodiment of the above-mentioned flare ignition control method for the offshore platform flare gas random ignition system, the offshore platform flare gas random ignition system further includes a flare distribution tank. The flare gas, after being processed by the flare distribution tank, is then delivered to the first flare gas burner. The flare ignition control method includes:

[0019] Obtain the pressure value inside the flare separator and determine the magnitude of the pressure value;

[0020] If the pressure value is greater than or equal to the first preset value, the control system controls the first flare gas burner to switch from off to on.

[0021] In a specific embodiment of the above-mentioned flare ignition control method for the offshore platform flare gas random ignition system, the flare ignition control method includes:

[0022] If the first flare gas burner is in the open state and there is no combustion flame at the first flare gas burner, then the control system controls the flare ignition system to start continuous ignition; and / or

[0023] If the pressure value of the flare separator is greater than the first preset value, the control system controls the flare ignition system to start ignition.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] 1. This invention can automatically control the start and stop of the flare ignition system based on the on / off state of the first flare gas burner and the flame state detected by the flame detector. That is, the flare ignition system is automatically started when the first flare gas burner is on and when the first flare gas burner is on but no flame is detected. It realizes the function of judging whether there is flare gas passing by whether the first flare gas burner is on or off and judging whether the flare gas is burning normally by whether there is a flame when it is on. Thus, it realizes the automatic ignition of flare gas and automatic monitoring function under various conditions, eliminating the need for a large amount of gas to maintain the lamp continuously, improving the stability of flare system ignition and the reliability of detection, and providing a solution for the green, low-carbon and safe emission of flare gas from offshore platforms.

[0026] 3. This invention determines whether to start the flare ignition system based on the pressure value detected in the flare separator, avoiding the problem of failure to automatically ignite the flare gas in time due to malfunction of the first flare gas burner switch detection, thus improving the stability of the flare system ignition and the reliability of detection.

[0027] 2. The micro-positive pressure regulating valve in the micro-positive pressure maintaining system designed in this invention can adjust the gas volume according to the pressure information detected by the pressure detector in the flare separator, ensuring the micro-positive pressure seal of the second flare gas burner exhaust pipe and preventing air from entering the exhaust pipe. The micro-positive pressure gas source can be nitrogen, reducing the amount of fuel gas used, which also helps to achieve the goal of green, low-carbon and safe emission of flare gas on offshore platforms. Attached Figure Description

[0028] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0029] Figure 1 This is a control flowchart of the offshore platform flare gas random ignition system provided by the present invention;

[0030] Figure 2 This is a schematic diagram showing the distribution of the first and second flare gas burners.

[0031] Figure 3 This is a flowchart of the steps involved in the automatic ignition and combustion control method for flare gas in a flare system.

[0032] List of reference numerals in the attached diagram:

[0033] 1. Control system; 2. Micro-positive pressure gas source; 3. Micro-positive pressure regulating valve; 4. Bypass valve; 5. Gas source delivery pipeline; 6. Flame gas source; 7. Flame gas main pipe; 8. Flame separator; 9. Pressure detector; 10. Switch status detector; 11. Flame detection host; 12. Ignition device status detector; 13. Ignition device; 14. First flame gas burner; 15. Flame arm; 16. Second flame gas burner; 17. Flame detector; 18. Windproof cover. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0035] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the system or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., used to define components are merely for the convenience of distinguishing the aforementioned components. Unless otherwise stated, these terms have no special meaning and should not be construed as indicating or implying relative importance.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] This invention relates to the field of offshore oil and gas field production technology, and in particular to a system for the random ignition of flare gas on offshore platforms and a method for controlling ignition and combustion. The aim is to address the problems of existing flare gas combustion and emission systems that require purge gas and a continuous flame to ensure timely ignition of the flare gas and a slight positive pressure seal at the flare head. These systems consume large amounts of fuel gas daily, resulting in resource waste and environmental pollution. To this end, the present invention provides a flare gas ignition system for offshore platforms, comprising a flare ignition system, a flame detector, a first flare gas burner, and a control system. The first flare gas burner is used to pass flare gas, the flare ignition system is used to ignite the first flare gas burner to burn the flare gas, the flame detector is used to detect the flame state of the first flare gas burner burning the flare gas, and the control system controls the start and stop of the flare ignition system according to the on / off state of the first flare gas burner and the flame state detected by the flame detector. That is, the flare ignition system is automatically started for automatic ignition when the first flare gas burner is in the on state and when the first flare gas burner is in the on state and no flame is detected. This realizes the function of judging whether there is flare gas passing through based on whether the first flare gas burner is in the on / off state and whether the flare gas is burning normally based on whether there is a flame when it is in the on state. Thus, it realizes the function of automatic ignition of flare gas under various conditions, eliminating the need for a large amount of gas to maintain the lamp continuously, improving the stability of the flare system ignition and the reliability of detection, and providing a solution for the green, low-carbon, and safe emission of flare gas from offshore platforms.

[0038] The following is a detailed description of the offshore platform flare gas ignition system and ignition and combustion control method provided in the embodiments of the present invention, with reference to the accompanying drawings.

[0039] See Figure 1 This invention provides a flare gas ignition system for offshore platforms. The flare system includes a flare ignition system, a flame detector, a first flare gas burner 14, and a control system 1. The first flare gas burner is used to pass flare gas, the flare ignition system is used to ignite the flare gas passing through the first flare gas burner 14, and the flame detector is used to detect the flame state of the flare gas burning in the first flare gas burner 14. The flare ignition system, the flame detector, and the first flare gas burner are all communicatively connected to the control system. The control system 1 controls the start and stop of the flare ignition system according to the on / off state of the first flare gas burner 14 and the flame state detected by the flame detector.

[0040] The flare system also includes a flare separator 8, a flare arm 15, and a flare gas main 7. The flare gas main 7 is used to supply the flare gas source 6. The inlet of the flare separator 8 is connected to the flare gas main 7, and the outlet of the flare separator 8 is connected to the inlet of the flare arm 15. The first flare gas burner 14 and the second flare gas burner 16 are both installed at the top of the flare arm 15 and connected to its outlet. A pressure detector 9 is installed on the flare separator 8. The pressure detector 9 is communicatively connected to the control system 1. The control system 1 controls the opening and closing of the first flare gas burner 14 and the start and stop of the flare ignition system based on the pressure information sent by the pressure detector 9. When the pressure value (pressure information) received by the control system 1 is greater than or equal to a first preset value, the control system controls the switch of the first flare gas burner 14 to open; when the pressure value is less than the first preset value, the control system controls the switch of the first flare gas burner 14 to close.

[0041] Specifically, control system 1 is a PLC control unit, that is, the PLC control unit includes a PLC controller. The first flare gas burner 14 is equipped with a switch and a switch status detector 10. The first flare gas burner described in this application is by default equipped with a switch and a switch status detector. The switch is used to control the opening and closing of the first flare gas burner 14. When open, it allows flare gas to pass through. The switch is connected to control system 1 and is used to control the switch to open or close based on the pressure signal detected by pressure detector 9. The switch status detector 10 is used to detect the state of the switch, i.e., whether it is in the open or closed state. The switch status detector 10 is communicatively connected to control system 1 and sends the detected switch status information to control system 1. Control system 1 controls the automatic start and stop of the flare ignition system according to the switch status. The pressure detector can be, but is not limited to, a pressure transmitter.

[0042] Furthermore, the first flare gas burner 14 can adjust its flow area according to the magnitude of the venting pressure; for example, the first flare gas burner 14 is a steplessly adjustable flare burner. In this application, the number of pressure detectors 9 is at least two, preferably, such as... Figure 1 As shown, there are three pressure detectors 9. When the pressure values ​​of the three pressure detectors 9 are obtained, it is necessary to determine whether the three pressure values ​​are the same. If at least two pressure values ​​are the same, the pressure value is taken as the current pressure value of the flare separator 8, which improves the accuracy and avoids affecting the overall operation of the flare system due to inaccurate measurement caused by damage to the pressure detectors 9.

[0043] In the above embodiments, there are three specific implementation methods for the control system 1 to control the torch ignition system to start ignition, as follows:

[0044] In the first implementation, when the control system 1 detects that the switch state of the first flare gas burner 14 has changed from closed to open, the control system controls the flare ignition system to start ignition. The switch of the first flare gas burner 14 changing from closed to open indicates that flare gas is passing through, and at this time, the flare ignition system needs to be started to ignite the first flare gas burner 14 to burn the flare gas.

[0045] In the second implementation, when the control system 1 detects that the first flare gas burner 14 is in the open state and the flame detector does not detect any combustion flame, the control system controls the flare ignition system to start continuous ignition. This situation occurs when the flare gas combustion may have extinguished for some reason during the combustion process. Therefore, in this case, the flare ignition system is still started for continuous ignition, thus realizing the automatic ignition function.

[0046] The third implementation involves the control system initiating ignition of the flare ignition system when it detects that the pressure in the flare separator exceeds a first preset value. This avoids the situation where a faulty switch detector on the first flare gas burner fails to detect the switch's on / off state, preventing the flare ignition system from automatically starting when flare gas passes through. In other words, if the switch detector is faulty while the first flare gas burner's switch is in the open state, the control system will initiate ignition in this case. This achieves automatic ignition of flare gas and automatic monitoring under various conditions, eliminating the need for large amounts of gas to maintain a continuously lit lamp, and improving the stability and reliability of the flare system's ignition.

[0047] The specific implementation of the control system 1 controlling the flare ignition system to shut down is as follows: when the control system 1 detects that the first flare gas burner 14 is in a closed state or the flame detector detects the presence of a combustion flame, the control system controls the flare ignition system to shut down.

[0048] The flare system designed in this invention enables automatic ignition of flare gas and automatic monitoring under various conditions, eliminating the need for large amounts of gas to maintain the continuous flame. This improves the stability of the flare system's ignition and the reliability of its detection, providing a solution for the green, low-carbon, and safe emission of flare gas from offshore platforms.

[0049] In one embodiment, the flare ignition system includes an ignition device 13 and an ignition device status detector 12. The ignition device 13 is used to ignite the flare gas, and the ignition device status detector 12 is used to detect the operating status of the ignition device 13. Both the ignition device status detector 12 and the ignition device 13 are communicatively connected to the control system 1. When the control system 1 detects that the switch of the first flare gas burner 14 is in the open state, the control system 1 controls the ignition device 13 to start ignition, thereby realizing the immediate ignition of the emitted flare gas.

[0050] In this embodiment, the ignition device status detector 12 is used to detect the working status of the ignition device and send the information to the control system. The control system determines whether the ignition device is off or on based on the information, thereby controlling the normal operation of the ignition device. Both the ignition gun and the ignition device status detector 12 are fixedly connected to the torch arm 15. The ignition device 13 can be located on one side of the first torch gas burner 14 and is set close to the first torch gas burner 14 to ensure that the ignition device 13 can immediately ignite the torch gas upon startup.

[0051] The flame detector 17 is installed directly above the first flare gas burner 14 to detect the combustion flame status of the first flare gas burner 14, that is, to determine whether there is a combustion flame and send the information to the control system.

[0052] It should be noted that this application does not specifically limit the installation location of the ignition device status detector 12. It can be flexibly set according to the actual situation without deviating from the basic principle of the present invention.

[0053] In one embodiment, see Figure 1-2 The flare system also includes a second flare gas burner 16, which is installed at the top of the flare arm 15 and communicates with its output port. The second flare gas burner 16 is normally open. There are at least three first flare gas burners 14, which are evenly distributed in a circumferential arrangement around the second flare gas burner 16. Each first flare gas burner 14 is matched with a flare ignition system and a flame detector. A wind shield 18 is provided on the outside of the output port of the flare arm 15 to surround the first flare gas burners 14 and the second flare gas burner 16.

[0054] This application presents two flare gas release conditions: the first is normal flare gas release (i.e., small-scale release, such as pressure 50 PaG, temperature 55℃, normal release volume 1000 cubic meters / day); the second is emergency flare gas release (i.e., large-scale release, such as pressure 50 PaG, temperature 55℃, emergency release volume 100,000 cubic meters / day). In the first flare gas release condition, the flare gas is discharged from the second flare gas burner 16. At this time, the flare ignition system is not activated, meaning the flare gas is directly released without combustion. The pressure in the flare separator 8 does not reach the first preset value, therefore the first flare gas burner 14 does not open. In the second flare gas release condition, the flare gas is not only discharged from the second flare gas burner 16, but also, because the pressure in the flare separator 8 reaches the first preset value, the control system 1 controls the first flare gas burner 14 to open and activates the flare ignition system for combustion and discharge.

[0055] In one embodiment, see Figure 1The flare system also includes a micro-positive pressure maintenance system, which includes a gas supply pipeline 5. One end of the gas supply pipeline 5 is used to supply a micro-positive pressure gas source 2, and the other end of the gas supply pipeline 5 is connected to the flare gas main pipe 7. A micro-positive pressure regulating valve 3 is installed on the gas supply pipeline 5, and the micro-positive pressure regulating valve 3 is communicatively connected to the control system 1. The control system adjusts the opening of the micro-positive pressure regulating valve according to the pressure value detected by the pressure detector. When the detected pressure value is greater than a second preset value, the control system controls the micro-positive pressure regulating valve to open wider.

[0056] Specifically, an isolation valve is installed on each of the gas supply pipelines 5 on both sides of the micro-positive pressure regulating valve 3 to isolate the gas supply during maintenance of the micro-positive pressure regulating valve 3. The micro-positive pressure gas source 2 can be, but is not limited to, nitrogen. The micro-positive pressure regulating valve 3 can regulate the flow rate of the micro-positive pressure gas source 2 into the flare separator 8. That is, the control system 1 controls the opening of the micro-positive pressure regulating valve 3 according to the received pressure information to ensure the micro-positive pressure seal of the exhaust pipe of the second flare gas burner 16 and prevent air from entering the exhaust pipe. The micro-positive pressure gas source 2 is nitrogen, which reduces the amount of fuel gas used and also helps to achieve the goal of green, low-carbon, and safe emissions of flare gas from offshore platforms.

[0057] In one embodiment, see Figure 1 The micro-positive pressure maintenance system also includes a bypass pipeline. One end of the bypass pipeline is connected to the gas supply pipeline 5 before the micro-positive pressure gas source 2 enters the micro-positive pressure regulating valve 3, and the other end of the bypass pipeline is connected to the flare gas main pipeline 7. A bypass valve 4 is installed on the bypass pipeline.

[0058] In the above embodiment, the bypass valve 4 can be manually controlled. When the micro-positive pressure regulating valve 3 is damaged, the bypass valve 4 can be manually opened to allow the micro-positive pressure gas source 2 to be sent from the bypass pipeline into the flare separator tank 8, which ensures the micro-positive pressure sealing of the exhaust pipe of the second flare gas burner 16 without affecting the maintenance of the micro-positive pressure regulating valve 3.

[0059] On the other hand, see Figure 3 The present invention also provides a flare ignition control method for a random ignition system for flare gas on an offshore platform. This random ignition system for flare gas on an offshore platform is the same as described in the above embodiments. Specifically, the random ignition system includes a first flare gas burner, a flame detector, a flare ignition system, and a control system. The first flare gas burner is used to pass flare gas, and the flare ignition system is used to ignite the flare gas passing through the first flare gas burner. The first flare gas burner, the flame detector, and the flare ignition system are all communicatively connected to the control system. The flare ignition control method includes:

[0060] S1, determine the on / off status of the first flare gas burner;

[0061] In this step, the control system determines the on / off status of the first flare gas burner based on the information received from the on / off detector of the first flare gas burner.

[0062] S11, if the switch state of the first flare gas burner changes from closed to open; then step S2 is executed, that is, the flare ignition system is started by the control system.

[0063] S12, if the first flare gas burner is in the off state, then step S4 is executed, that is, the flare ignition system is shut down by the control system.

[0064] In the above steps, when the control system determines that the switch state of the first flare gas burner has changed from closed to open, it controls the flare ignition system to start ignition.

[0065] After executing step S2, execute step S3, which is to determine the flame state of the first flare gas burner.

[0066] In this step, the flame detector detects the flame state and sends the detected information to the control system. The control system then determines the flame state of the first flare gas burner based on the received information.

[0067] S31, if there is a combustion flame at the first flare gas burner, then execute step S4, that is, the control system controls the flare ignition system to shut off the ignition.

[0068] In this step, the control system determines that there is a combustion flame at the first flare gas burner or that the first flare gas burner is in a closed state, and then controls the flare ignition system to shut off the ignition.

[0069] In one embodiment, the offshore platform flare gas ignition system further includes a flare separator, through which the flare gas is processed and then delivered to a first flare gas burner. The flare ignition control method includes:

[0070] S5, obtain the pressure value inside the flare separator and determine the magnitude of the pressure value;

[0071] In this step, the pressure detector sends the detected pressure value to the control system, which then determines the magnitude based on the received pressure value.

[0072] S6. If the pressure value is greater than or equal to the first preset value, then proceed to step S7, that is, the control system controls the first flare gas burner to switch from off to on. If the pressure value is less than the first preset value, the first flare gas burner remains off.

[0073] In one embodiment, the torch ignition control method includes:

[0074] S13, If the first flare gas burner is in the open state, determine the flame state of the first flare gas burner;

[0075] If there is no combustion flame at the first flare gas burner, then step S8 is executed, that is, the flare ignition system is controlled by the control system to start continuous ignition.

[0076] In one embodiment, the torch ignition control method includes:

[0077] S6. If the pressure value in the flare separator is greater than the first preset value, then step S2 is executed, that is, the control system controls the flare ignition system to start ignition. This invention determines whether to start the flare ignition system based on the detected pressure value in the flare separator, avoiding the problem of flare gas not being automatically ignited in time due to malfunction in the switch detection of the first flare gas burner, thus improving the stability and reliability of the flare system ignition.

[0078] In the above embodiments, this application can achieve automatic ignition of flare gas and automatic monitoring functions under various conditions, eliminating the need for a large amount of gas to maintain the lamp continuously, improving the stability of flare system ignition and the reliability of detection, and providing a solution for green, low-carbon and safe emission of flare gas from offshore platforms.

[0079] It should also be noted that the present invention does not impose specific limits on the first and second preset values, and they can be flexibly set according to the actual situation without deviating from the basic principles of the present invention.

[0080] The working process of this invention under two pressure relief conditions is described in detail below:

[0081] Under normal venting conditions, the pressure is 50 PaG, the temperature is 55℃, and the normal venting gas volume is 1000 cubic meters per day. Under normal venting conditions, the flare gas, after being purified of droplets and some water vapor by the flare separator, enters the flare arm and is burned by the normally open burner located in the center of the windproof shroud before being vented. The control system automatically monitors the flare gas pressure (pressure in the flare separator) and the on / off status of the first flare gas burner. The first flare gas burner is in the off state. The designed purge gas volume is 15 cubic meters per hour. The micro-positive pressure regulating valve adjusts the purge gas volume according to the pressure signal from the pressure detector to ensure a micro-positive pressure seal on the discharge pipe of the second flare gas burner, preventing air from entering the flare network.

[0082] In an emergency flare gas release operation, with a pressure of 50 PaG and a temperature of 55°C, the emergency release volume is 100,000 cubic meters per day. A large amount of flare gas enters the flare system through the flare arm. Pressure detectors send the detected pressure information to the control system. When the pressure value is greater than or equal to a first preset value, the control system controls the switch of the first flare gas burner to open. Upon receiving this information, the control system activates the flare ignition system to ignite the flare gas emitted from the first burner. A flame detector detects the combustion flame; if a flame is present, the flare ignition system is shut down. During the emergency release process, if the flame is detected to be extinguished (i.e., no flame), the control system will also activate the flare ignition system to ignite the first flare gas burner.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for the random ignition of flare gas on an offshore platform, characterized in that, The flare system includes a flare ignition system, a flame detector, a first flare gas burner, and a control system. The first flare gas burner is used to pass flare gas, the flare ignition system is used to ignite the flare gas passing through the first flare gas burner, and the flame detector is used to detect the flame state of the flare gas burning in the first flare gas burner. The flare ignition system, the flame detector, and the first flare gas burner are all communicatively connected to the control system. The control system controls the start-up and shutdown of the flare ignition system based on the on / off state of the first flare gas burner and the flame state detected by the flame detector. The flare system also includes a second flare gas burner, which is normally open. There are at least three first flare gas burners that are evenly distributed around the second flare gas burner in a circular arrangement. Each first flare gas burner is matched with a flare ignition system and a flame detector. When the control system detects that the switch state of the first flare gas burner has changed from closed to open, the control system controls the flare ignition system to start ignition. When the control system detects that the first flare gas burner is in the open state and the flame detector does not detect the presence of a combustion flame, the control system controls the flare ignition system to start continuous ignition. The flare system also includes a flare arm, and the first flare gas burner and the second flare gas burner are both installed at the top of the flare arm and connected to its output port. The flare system also includes a micro-positive pressure maintenance system, which includes a gas source delivery pipeline. One end of the gas source delivery pipeline is connected to a micro-positive pressure gas source, and the other end of the gas source delivery pipeline is connected to the flare gas main. A micro-positive pressure regulating valve is installed on the gas source delivery pipeline, and the micro-positive pressure regulating valve is communicatively connected to the control system.

2. The offshore platform flare gas ignition system according to claim 1, characterized in that, When the control system detects that the first flare gas burner is in a closed state or the flame detector detects the presence of a combustion flame, the control system controls the flare ignition system to shut down.

3. The offshore platform flare gas ignition system according to claim 1, characterized in that, The flare system also includes a flare separator and a flare gas main. The inlet of the flare separator is connected to the flare gas main, and the outlet of the flare separator is connected to the inlet of the flare arm. A pressure detector is installed on the flare separator and is communicatively connected to the control system. The control system controls the opening and closing of the first flare gas burner and the start and stop of the flare ignition system based on the pressure information sent by the pressure detector.

4. The offshore platform flare gas ignition system according to claim 1, characterized in that, The torch ignition system includes an ignition device and an ignition device status detector. The ignition device is used to ignite the torch gas, and the ignition device status detector is used to detect the working status of the ignition device. Both the ignition device status detector and the ignition device are communicatively connected to the control system.

5. A method for controlling the flare ignition of a offshore platform flare gas ignition system as described in any one of claims 1-4, characterized in that, The offshore platform flare gas ignition system includes a first flare gas burner, a flare ignition system, and a control system. The first flare gas burner is used to pass flare gas, and the flare ignition system is used to ignite the flare gas passing through the first flare gas burner. Both the first flare gas burner and the flare ignition system are communicatively connected to the control system. The flare ignition control method includes: Determine the on / off status of the first flare gas burner; If the switch state of the first flare gas burner changes from closed to open, the control system controls the flare ignition system to start ignition. Determine the flame state of the first flare gas burner; If there is a combustion flame at the first flare gas burner or the first flare gas burner is in a closed state, the control system controls the flare ignition system to shut down the ignition.

6. The flare ignition control method for the offshore platform flare gas random ignition system according to claim 5, characterized in that, The offshore platform flare gas ignition system further includes a flare separator, through which the flare gas is processed and then delivered to the first flare gas burner. The flare ignition control method includes: Obtain the pressure value inside the flare separator and determine the magnitude of the pressure value; If the pressure value is greater than or equal to the first preset value, the control system controls the first flare gas burner to switch from off to on.

7. The flare ignition control method for the offshore platform flare gas random ignition system according to claim 6, characterized in that, The torch ignition control method includes: If the first flare gas burner is in the open state and there is no combustion flame at the first flare gas burner, then the control system controls the flare ignition system to start continuous ignition; and / or If the pressure value of the flare separator is greater than the first preset value, the control system controls the flare ignition system to start ignition.

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