A hot gas condensation recovery device for oil well pollution prevention casing

Abstract

This utility model discloses a hot gas condensation and recovery device for oil well casing to prevent contamination, including a mounting frame and a controller, a condenser, a sealed liquid storage tank, a gas-liquid guide, and a filter-guide assembly mounted thereon. The condenser is mounted on the mounting frame and has an inlet pipe, an outlet pipe, and a drain pipe. The sealed liquid storage tank is mounted on the mounting frame and has a drain pipe. The gas-liquid guide has an injection pipe for unified entry of hot gas, a guide pipe connected to the inlet pipe, and a guide pipe connected to the sealed liquid storage tank. The filter-guide assembly has an inlet end connected to the drain pipe and an outlet end connected to the sealed liquid storage tank. The gas discharged through the outlet pipe and the liquid discharged through the drain pipe are configured to be injected into the oil well pipeline respectively. This device can process and recover the returned hot gas in the oil well casing, achieving both contamination prevention and resource recovery.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field development technology, and more specifically, to a hot gas condensation and recovery device for oil well anti-pollution casing. Background Technology

[0002] During oil well production, high-temperature hot gas is often injected downhole to dilute heavy oil. After the hot gas completes its operation, it carries a mixture of gases (containing 70% steam, natural gas, a small amount of hydrogen sulfide, crude oil, etc.) back through the casing. Currently, this backflowing mixture is typically separated into gas and liquid phases using a condenser before being injected into the oil well's pipeline.

[0003] For example, patent number CN204202426U discloses a condenser for tail gas from a fire-driven oil well, which achieves rapid gas-liquid separation of the mixed gas through condensation. However, the mixed gas contains a small amount of crude oil, and directly using this method will cause the crude oil to cool and solidify, clogging the condenser pipeline. Furthermore, the liquid after condensation and separation is directly introduced into the collection without filtration, which will also cause pipeline blockage. Utility Model Content

[0004] The main objective of this application is to provide an oil well anti-pollution casing hot gas condensation and recovery device to solve the problems in the prior art where crude oil condenses and blocks the condenser pipeline after the mixed gas is directly separated by condensation, and subsequent direct drainage blocks the delivery pipeline.

[0005] This utility model provides a hot gas condensation and recovery device for oil well anti-pollution casing, including a mounting frame and a controller mounted on the mounting frame, and further including a condenser, a sealed liquid storage tank, a gas-liquid guide, and a filter-guide assembly. The condenser, mounted on the mounting frame, has an inlet pipe, an outlet pipe, and a drain pipe. The sealed liquid storage tank, mounted on the mounting frame and located below the condenser, has a drain pipe. The gas-liquid guide has an injection pipe, a guide pipe, and a drain pipe. The injection pipe is used for the unified entry of hot gas, the guide pipe is connected to the inlet pipe, and the drain pipe is connected to the sealed liquid storage tank. The filter-guide assembly has an inlet end and a drain end. The inlet end is connected to the drain pipe, and the drain end is connected to the sealed liquid storage tank. The gas discharged through the outlet pipe and the liquid discharged through the drain pipe are configured to be injected into the oil well pipeline, respectively.

[0006] Furthermore, the filtration and liquid guiding assembly includes a shut-off valve, a filter valve, a drain valve, and a drain pipe connected in series; the shut-off valve forms the liquid inlet end, and the drain pipe forms the liquid outlet end.

[0007] Furthermore, the condenser is an air-cooled condenser.

[0008] Furthermore, the exhaust pipe is connected to an air pump unit, and the liquid outlet pipe is connected to a liquid pump unit. The gas discharged from the exhaust pipe and the liquid discharged from the liquid outlet pipe are injected into the oil well pipeline through the respective air pump units and liquid pump units.

[0009] Furthermore, a liquid level switch is installed inside the sealed liquid storage tank, so that when the liquid level in the sealed liquid storage tank reaches a set value, the liquid pump unit automatically injects the liquid into the oil well pipeline.

[0010] Compared with the prior art, the beneficial effects of this utility model are: In the oil well anti-pollution casing hot gas condensation and recovery device described in this utility model, the pre-separation of the gas-liquid guide and the post-filtration of the filter guide assembly effectively avoid the problem of crude oil condensation clogging the condenser pipeline and subsequent transportation pipeline, ensuring the long-term stable operation of the system. At the same time, the condensed gas and the filtered liquid are independently injected into the oil pipeline through the exhaust pipe and liquid outlet pipe, respectively, realizing efficient recovery of gas and liquid classification and improving resource utilization. In addition, the entire process is completed in a closed storage tank and closed pipeline, effectively preventing the leakage of harmful gases such as hydrogen sulfide, combining safety and environmental protection. The overall structure is compact and easy to control, and it is suitable for the actual operation needs of oilfield sites. Attached Figure Description

[0011] Figure 1 A schematic diagram of the overall structure of an oil well anti-pollution casing hot gas condensation and recovery device provided in this application embodiment; Figure 2 This is a schematic diagram showing the connection positions of the air pump unit and the liquid pump unit provided in the embodiments of this application.

[0012] Reference numerals: 10, mounting bracket; 20, controller; 30, condenser; 31, air inlet pipe; 32, exhaust pipe; 33, drain pipe; 40, sealed liquid storage tank; 41, liquid outlet pipe; 42, liquid level switch; 50, gas-liquid guide; 51, air injection pipe; 52, air guide pipe; 53, liquid guide pipe; 60, filter liquid guide assembly; 61, shut-off valve; 62, filter valve; 63, drain valve; 64, drain pipe; 70, air pump unit; 80, liquid pump unit. Detailed Implementation

[0013] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0014] The embodiments of this application aim to condense, separate, and recover the returned mixed gas. In the description of this application, the term "below" refers to a positional relationship pointing towards the ground along the direction of gravity; the term "series connection" refers to multiple components being connected end-to-end through a pipe to form a single fluid channel.

[0015] like Figure 1 As shown in the figure, this application provides an oil well anti-pollution casing hot gas condensation and recovery device, including a mounting frame 10 and a controller 20 disposed on the mounting frame 10, and also including a condenser 30, a sealed liquid storage tank 40, a gas-liquid guide 50, and a filter and guide assembly 60. The condenser 30 is disposed on the mounting frame 10 and has an air inlet pipe 31, an air outlet pipe 32, and a liquid outlet pipe 33. The sealed liquid storage tank 40 is disposed on the mounting frame 10 and below the condenser 30, and has a liquid outlet pipe 41. The gas-liquid guide 50 has an air injection pipe 51, an air guide pipe 52, and a liquid guide pipe 53. The air injection pipe 51 is used for the unified entry of hot gas, the air guide pipe 52 is connected to the air inlet pipe 31, and the liquid guide pipe 53 is connected to the sealed liquid storage tank 40. The filter and guide assembly 60 has a liquid inlet end and a liquid outlet end. The liquid inlet end is connected to the liquid outlet pipe 33, and the liquid outlet end is connected to the sealed liquid storage tank 40. The gas discharged through the exhaust pipe 32 and the liquid discharged through the liquid outlet pipe 41 are configured to be injected into the oil well pipeline, respectively. According to this embodiment, the device uses a gas-liquid guide 50 (e.g., a three-way or four-way valve body structure with multi-channel distribution function) as a fluid distribution hub to uniformly receive the hot gas returning from the oil well casing and guide it to the condenser 30. The condenser 30 condenses the water vapor in the gas into liquid through heat exchange, and discharges it along with entrained tiny droplets through the liquid outlet pipe 33, achieving preliminary gas-liquid separation. This portion of the condensate is treated by the filter and liquid guiding assembly 60 and then guided to a sealed storage tank 40 for storage; while the non-condensable gas remaining after treatment by the condenser 30 is discharged from the exhaust pipe 32. Finally, the gas discharged from the exhaust pipe 32 and the liquid discharged from the liquid outlet pipe 41 are respectively injected back into the oil well pipeline.

[0016] In practical applications, the overall working process of this oil well anti-pollution casing hot gas condensation and recovery device is as follows: The hot gas returning from the oil well casing first enters the injection pipe 51, and the gas-liquid diverter 50 diverts it. Most of the gas enters the condenser 30 through the gas guide pipe 52 and the gas inlet pipe 31 for condensation and separation. The separated liquid enters the filter liquid guide assembly 60 through the drain pipe 33, and after purification, flows into the sealed liquid storage tank 40. The separated non-condensable gas is discharged through the exhaust pipe 32. A small amount of crude oil separated by the gas-liquid diverter 50 is directly introduced into the sealed liquid storage tank 40. Subsequently, the liquid in the sealed liquid storage tank 40 is discharged through the outlet pipe 41, and the gas discharged through the exhaust pipe 32 is pressurized and reinjected into the oil well pipeline, completing the entire anti-pollution and resource recovery cycle.

[0017] In one embodiment, the filtration and guiding liquid assembly 60 includes a shut-off valve 61, a filter valve 62, a drain valve 63, and a drain pipe 64 connected in series. The shut-off valve 61 forms the liquid inlet, and the drain pipe 64 forms the liquid outlet. Specifically, the shut-off valve 61 controls the overall on / off of the pipeline, facilitating equipment maintenance; the filter valve 62 has a filter element (such as a stainless steel sintered mesh filter element) inside to intercept solid impurities in the condensate; the drain valve 63 (such as a mechanical or thermodynamic drain valve) utilizes the difference in gas-liquid density or temperature to allow liquid to pass through while blocking gas; the drain pipe 64 guides the treated liquid to the sealed storage tank 40. Based on the above principles, this series configuration can bring unique and beneficial effects of step-by-step purification and gas blocking drainage: the filter valve 62 ensures the purity of the liquid entering the sealed storage tank 40, preventing impurities from accumulating; the drain valve 63 effectively prevents uncondensed gas from entering the sealed storage tank 40, avoiding pressure fluctuations inside the sealed storage tank 40, and improving the quality of the recycled water and the stability of system operation. As a specific implementation method, the filter element pore size of filter valve 62 can be specifically selected according to the sand content of the oil well produced fluid to ensure optimal filtration accuracy and flow capacity.

[0018] In a further embodiment, the condenser 30 is an air-cooled condenser. A sealed liquid storage tank 40 is located below the air-cooled condenser. Specifically, the air-cooled condenser utilizes a fan and heat dissipation fins for air cooling, requiring no external cooling water source; the sealed liquid storage tank 40 being located below means that it is arranged along the direction of gravity at the bottom of the condenser 30. This structural configuration provides a combination of adaptability to the field environment and energy saving: on the one hand, the air-cooled condenser perfectly adapts to the working conditions of oilfields where cooling water sources are scarce; on the other hand, the sealed liquid storage tank 40 being located below allows full utilization of gravitational potential energy, enabling the condensate generated by the condenser 30 to flow by gravity into the filter and liquid guiding assembly 60 and the sealed liquid storage tank 40, eliminating the need for additional liquid transport power and significantly reducing the overall energy consumption of the system.

[0019] like Figure 2 As shown, in a further embodiment, the exhaust pipe 32 is connected to a gas pump unit 70, and the liquid outlet pipe 41 is connected to a liquid pump unit 80. The gas discharged from the exhaust pipe 32 and the liquid discharged from the liquid outlet pipe 41 are injected into the oil well pipeline through the respective gas pump unit 70 and liquid pump unit 80. Specifically, the gas pump unit 70 can be a gas compressor or a Roots blower, and the liquid pump unit 80 can be a centrifugal pump or a plunger pump. Both independently construct gas reinjection circuits and liquid reinjection circuits. Based on the above principle, this independent pumping configuration can bring unique and beneficial effects of avoiding gas-liquid interference and protecting the equipment: injecting gas and liquid independently into the oil well pipeline effectively avoids cavitation or gas lock problems that are easily generated during gas-liquid mixing and transportation, prevents mechanical damage to each pump unit, thereby significantly extending the service life of the equipment and ensuring the stability of the reinjection pressure.

[0020] In a further embodiment, such as Figure 2 As shown, a level switch 42 is installed inside the sealed storage tank 40. Once the liquid level in the sealed storage tank 40 reaches a set value, the pump unit 80 automatically injects the liquid into the oil well pipeline. Specifically, the level switch 42 can be a float level switch or an electrode level switch, installed high on the inner wall of the sealed storage tank 40. When the liquid level rises and triggers the level switch 42, the controller 20 receives the signal and starts the pump unit 80. This configuration provides unique advantages in automatic control and safety protection: it enables automatic monitoring and drainage of the liquid level in the sealed storage tank 40, effectively preventing secondary pollution caused by overflow of the sealed storage tank 40, and avoiding the pump unit 80 from running dry due to low water levels. Regarding the aforementioned "set value", since the return gas volume and condensation rate of different oil wells are different, the set value is not fixed. However, those skilled in the art can obtain the range of liquid level changes that can prevent overflow and avoid dry pumping by experiment or by calculating based on the effective volume of the sealed liquid storage tank 40 and the rated flow rate of the liquid pump unit 80, and input it into the controller 20 as the selected threshold.

[0021] Furthermore, it should be noted that in some alternative embodiments, the gas-liquid diverter 50 can also be replaced by a combination of multiple independently controlled solenoid valves to achieve the same multi-channel fluid distribution function; the surface of the heat dissipation fins of the condenser 30 can be coated with an anti-corrosion coating to resist corrosion from acidic gases such as hydrogen sulfide; the mounting bracket 10 can adopt a modular splicing structure to facilitate rapid assembly and disassembly at the oilfield well site.

[0022] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A hot gas condensation and recovery device for oil well anti-pollution casing, comprising a mounting frame and a controller disposed on the mounting frame, characterized in that, Also includes: A condenser, disposed on the mounting bracket, has an inlet pipe, an outlet pipe, and a drain pipe; A sealed liquid storage tank is installed on the mounting bracket and located below the condenser, and has a liquid outlet pipe; A gas-liquid diverter includes an injection pipe, a guide pipe, and a liquid guide pipe. The injection pipe is used for the unified entry of hot gas. The guide pipe is connected to the inlet pipe, and the liquid guide pipe is connected to the sealed liquid storage tank. The filtration liquid guiding assembly has a liquid inlet end and a liquid outlet end, wherein the liquid inlet end is connected to the liquid outlet pipe and the liquid outlet end is connected to the sealed liquid storage tank; The gas discharged through the exhaust pipe and the liquid discharged through the liquid outlet pipe are configured to be injected into the oil well pipeline, respectively.

2. The oil well anti-pollution casing hot gas condensation and recovery device according to claim 1, characterized in that, The filtration and liquid guiding assembly includes a shut-off valve, a filter valve, a drain valve, and a drain pipe connected in series; the shut-off valve forms the liquid inlet end, and the drain pipe forms the liquid outlet end.

3. The oil well anti-pollution casing hot gas condensation and recovery device according to claim 1, characterized in that, The condenser is an air-cooled condenser.

4. The oil well anti-pollution casing hot gas condensation and recovery device according to claim 1, characterized in that, The exhaust pipe is connected to an air pump unit, and the liquid outlet pipe is connected to a liquid pump unit. The gas discharged from the exhaust pipe and the liquid discharged from the liquid outlet pipe are injected into the oil well pipeline through the air pump unit and the liquid pump unit, respectively.

5. The oil well anti-pollution casing hot gas condensation and recovery device according to claim 4, characterized in that, A liquid level switch is installed inside the sealed liquid storage tank. Once the liquid level in the sealed liquid storage tank reaches a set value, the liquid pump unit automatically injects the liquid into the oil well pipeline.

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