An in-line cleaning filter, natural gas field station separation blowdown system and method of use

Abstract

The application relates to a filter of a natural gas production site gas-liquid separator blowdown system, which comprises a filter body, the filter body comprises a lower cavity and an upper cavity, a filter screen is arranged between the lower cavity and the upper cavity; the lower cavity is connected with a liquid inlet, a lower end cover is fixedly connected to the bottom of the lower cavity, a lower elbow assembly is fixedly connected to the outside of the lower end cover, and the lower elbow assembly is connected with a backwashing liquid outlet; the upper cavity is connected with a liquid outlet, an upper end cover is fixedly connected to the upper part of the upper cavity, an upper elbow assembly is fixedly connected to the outside of the upper end cover, and the upper elbow assembly is connected with a backwashing liquid inlet. The application also comprises a use method of the above-mentioned blowdown system. The filter of the application is installed on the pipeline of the natural gas gas-liquid separator blowdown system, filters the liquid separated by the separator, and prevents impurities in the liquid from adversely affecting the use efficiency of an electric ball valve and a control valve in the blowdown system.

Description

Technical Field

[0001] This invention relates to a sewage discharge system for natural gas stations and its usage. Background Technology

[0002] At natural gas production sites, the extracted natural gas carries impurities such as water, rock fragments, and corrosion products. To meet process requirements, separators are often used to separate the water and impurities from the natural gas, which are then discharged through a sump system. With the improvement of automation, electric ball valves are widely used in separator sump systems to reduce the labor intensity of workers. However, due to the influence of impurities in the liquid, the friction between the sealing ball and the valve seat increases during the opening and closing of the electric ball valve, damaging the sealing surface. At the same time, solid impurities can also deposit on the sealing surface of the control valve, preventing the valve core from closing tightly and causing internal leakage.

[0003] Currently, in natural gas production sites, there is no effective technology to prevent impurities in the separator's drainage system from affecting electric ball valves and control valves during the separation of gas and impurities. As a result, the service life of electric ball valves and control valves in the separator's drainage system at natural gas production sites is greatly shortened. At the same time, there are cases where electric ball valves and control valves do not close tightly, posing serious safety hazards to natural gas production. Summary of the Invention

[0004] The purpose of this invention is to provide an online cleaning filter, a natural gas station separation and sewage discharge system using the above-mentioned filter, and a method of using it.

[0005] To achieve the above objectives, the present invention employs an online cleaning filter, comprising a filter body, wherein the filter body includes a lower cavity and an upper cavity, and a filter screen is disposed between the lower cavity and the upper cavity; the lower cavity is connected to an inlet, and a lower end cap is fixedly connected to the bottom of the lower cavity, and a lower bend pipe assembly is fixedly connected to the outside of the lower end cap, the lower bend pipe assembly being connected to a backwash outlet; the upper cavity is connected to an outlet, and an upper end cap is fixedly connected to the upper part of the upper cavity, an upper bend pipe assembly is fixedly connected to the outside of the upper end cap, the upper bend pipe assembly being connected to a backwash inlet.

[0006] When this filter is in normal use for filtering wastewater, the wastewater enters through the inlet located at the bottom of the filter. This allows particles in the wastewater to collide with the filter screen above, and most of them are deposited in the lower chamber under gravity, rather than accumulating on the filter screen. This extends the filter's flushing cycle and reduces its failure rate. However, if impurities accumulate on the filter screen and affect the filtration efficiency, it is not necessary to disassemble the filter. The filter screen can be cleaned by introducing liquid from the backwash inlet at the top to perform a reverse flush.

[0007] A further improvement is that the backwash inlet pipe connected to the backwash inlet is horizontally positioned. With the backwash inlet of this filter horizontally feeding in, the liquid impacts the inner wall and reflects onto the filter screen, thus increasing the area through which the liquid passes and improving the cleaning effect.

[0008] A further improvement is that a lower perforated plate is installed between the lower cavity and the filter screen; and an upper perforated plate is installed between the upper cavity and the filter screen. Perforated plates are installed on both the upper and lower sides of the filter screen inside the filter. These plates have appropriate strength and hardness and are fitted to the inner wall of the filter. Sufficient circular holes are opened on them to allow liquid flow. Their function is to block larger particles of impurities, which is beneficial for filtering large and small particles of impurities in the separator's sewage system, preventing damage to the valves in the sewage system, and reducing its failure rate.

[0009] A further improvement is that a lower filter screen spacer ring is provided between the filter screen and the lower perforated plate; and an upper filter screen spacer ring is provided between the filter screen and the upper perforated plate. The spacer rings ensure a sealed contact between the outer edges of the filter screen and the upper and lower perforated plates.

[0010] A further improvement is that the filter screen is woven from stainless steel wire. This extends the filter screen's lifespan in harsh working environments, effectively blocking small-particle impurities while allowing impurity-free liquid flow to pass through.

[0011] The present invention also includes a natural gas station separation and discharge system using the above-mentioned filter, comprising a separator, a main process control valve, a first flushing process control valve, a second flushing process control valve, a filter, and an electric ball valve; the discharge port of the separator is connected to the inlet of the filter via a first pipeline, and the main process control valve is installed on the first pipeline; the outlet of the filter is connected to a gas field water tank via a second pipeline, and a ball valve is installed on the second pipeline; the discharge port of the separator is also connected to the first backwash inlet of the filter via a third pipeline connected to the first pipeline, and the first flushing process control valve is installed on the third pipeline; the backwash outlet of the filter is connected to a gas field water tank via a fourth pipeline, and the second flushing process control valve is installed on the fourth pipeline.

[0012] The system of this invention controls the switching between normal wastewater discharge and backwashing processes via a control valve. When the separator wastewater discharge system is in normal production and discharging separator wastewater, the accumulated liquid in the separator enters the lower chamber of the filter through the main process control valve. Under the pressure of natural gas, the liquid passes through the lower screen plate, lower filter screen partition ring, filter screen, upper filter screen partition ring, and upper screen plate, entering the upper chamber of the filter. It then flows out from the normal production outlet to the electric ball valve and is discharged to the gas field water tank.

[0013] When impurities accumulate on the filter screen, the backwashing process is initiated. The main process control valve and the electric ball valve are closed, and the first and second flushing process control valves are opened. Under the pressure of natural gas, liquid enters the upper chamber through the first flushing process control valve and the backwash inlet. After the upper screen plate blocks a small number of large particles of impurities, the liquid passes through the filter screen, flushing the impurities deposited on the filter screen into the lower chamber. After passing through the lower chamber backwash outlet and the second flushing process control valve, it is discharged to the gas field water pool.

[0014] A further improvement is that the third pipeline connecting to the first flushing process control valve is installed vertically on the first pipeline connecting to the main process control valve. This structure helps prevent large particles of impurities from entering the backwash inlet and accumulating in the upper cavity of the filter.

[0015] A further improvement is that the filter body axis is inclined at a 60° angle to the horizontal plane, with a length-to-diameter ratio of 2.0, a porosity of 0.7, and a filter layer thickness of 70mm. The filter is installed at a 60-degree angle to the horizontal. When wastewater passes through the filter screen and perforated plate inside the filter, it helps to filter large and small particles of impurities in the separator's sewage system, preventing damage to the electric ball valves and control valves of the sewage system.

[0016] A further improvement includes a manual wastewater discharge device. The wastewater discharge port of the separator is connected to the gas field water tank via a fifth pipeline. A main manual wastewater discharge valve and a manual valve sleeve type wastewater discharge valve are installed before and after the fifth pipeline, respectively. A sampling valve is connected between the main manual wastewater discharge valve and the manual valve sleeve type wastewater discharge valve via a pipeline. When it is necessary to test the wastewater composition, the manual valve sleeve type wastewater discharge valve is closed, and the main manual wastewater discharge valve and the sampling valve are opened in sequence to collect a sample. Alternatively, if needed, when the wastewater does not need to enter the filtration system, the sampling valve can be closed, and the main manual wastewater discharge valve and the manual valve sleeve type wastewater discharge valve can be opened in sequence, allowing the wastewater to go directly to the gas field water tank.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) This filter is designed with backwash inlet and outlet, which can easily wash away the tiny particulate impurities deposited on the filter screen inside the filter, preventing impurities from clogging the filter and affecting the filtration effect.

[0019] (2) This invention patent optimizes the structure of the filter. The filtration and backwashing effects are better. This solves the problem of impurities in the liquid discharged from the separator's sewage system causing damage to the electric ball valve and control valve, thereby improving the service life of the electric ball valve and control valve, reducing production and maintenance costs, and improving safe production.

[0020] (3) The present invention has the advantages of simple design, effective prevention of impurities from affecting the performance of electric ball valves and control valves, reduction of labor intensity of personnel, and improvement of valve service life, thus improving economic and safety benefits. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the natural gas station sewage separation system according to Embodiment 1 of the present invention.

[0022] Figure 2 : Figure 2-1 Schematic diagram of the filter structure of the natural gas separator's sewage system; Figure 2-2 yes Figure 2-1 The filter screen in the middle, Figure 2-3 yes Figure 2-1 The plug plate in the middle.

[0023] Figure 3 This is a schematic diagram of the natural gas station separation and sewage discharge system according to Embodiment 2 of the present invention.

[0024] Figure 4 This is a simulation of the filter structure for online cleaning functionality. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solution of the present invention will be further described below in conjunction with the accompanying drawings and embodiments. Example

[0026] like Figure 1 As shown, the natural gas station's wastewater separation system includes a separator 1, a main process control valve 2, a first flushing process control valve 3, a second flushing process control valve 6, a filter 4, and an electric ball valve 5. The separator's wastewater outlet is connected to the filter's inlet via a first pipeline, on which the main process control valve is installed. The filter's outlet is connected to a gas field water tank via a second pipeline, on which a ball valve is installed. The separator's wastewater outlet is also connected to the filter's first backwash inlet via a third pipeline connected to the first pipeline, on which the first flushing process control valve is installed. The filter's backwash outlet is connected to the gas field water tank via a fourth pipeline, on which the second flushing process control valve is installed. The third pipeline connecting to the first flushing process control valve is installed vertically to the first pipeline connecting to the main process control valve.

[0027] like Figure 2As shown, an online cleaning filter includes: a filter body comprising a lower cavity 11 and an upper cavity 18, wherein a lower perforated plate 12, a lower filter screen spacer ring 13, a filter screen 14, an upper filter screen spacer ring 15, and an upper perforated plate 16 are sequentially arranged between the lower cavity and the upper cavity; the lower cavity is connected to an inlet 7, and a lower end cap 9 is fixedly connected to the bottom of the lower cavity, with a lower bend pipe assembly fixedly connected to the outside of the lower end cap, and the lower bend pipe assembly is connected to a backwash outlet 10; the upper cavity is connected to an outlet 21, and an upper end cap 20 is fixedly connected to the upper part of the upper cavity, with an upper bend pipe assembly fixedly connected to the outside of the upper end cap, and the upper bend pipe assembly is connected to a backwash inlet 19. The backwash inlet pipe connected to the backwash inlet is horizontally arranged.

[0028] The method of using this invention patent is as follows:

[0029] When the separator wastewater system is in normal production and discharging separator wastewater, the wastewater accumulated in the separator enters the lower chamber of the filter through the main process control valve. Under the pressure of natural gas, the liquid passes through the lower screen plate, lower filter screen partition ring, filter screen, upper filter screen partition ring and upper screen plate, enters the upper chamber of the filter, and flows out from the normal production outlet to the electric ball valve, and is discharged to the gas field water pool.

[0030] When impurities accumulate on the filter screen, close the main process control valve and the electric ball valve, and open the first and second flushing process control valves. Under the pressure of natural gas, the liquid enters the upper chamber through the backwash inlet of the first flushing process control valve. After the upper screen plate blocks a small number of large particles of impurities, the liquid passes through the filter screen, flushing the impurities deposited on the filter screen into the lower chamber. After passing through the backwash outlet of the lower chamber and the second flushing process control valve, it is discharged to the gas field water pool. Example

[0031] Compared with Embodiment 1, the sewage discharge system of the present invention also includes a manual sewage discharge device, such as... Figure 3 As shown, the separator's drain outlet 22 is connected to the gas field water tank via the fifth pipeline. A manual main drain valve 23 and a manual valve sleeve type drain valve 25 are respectively installed before and after the fifth pipeline. A sampling valve 24 is connected between the manual main drain valve and the manual valve sleeve type drain valve via a pipeline.

[0032] As a preferred embodiment of the above embodiments, the filter screen of the present invention is made of woven stainless steel wire.

[0033] Further optimization involves the filter body axis being inclined at a 60° angle to the horizontal plane, having a length-to-diameter ratio of 2.0, a porosity of 0.7, and a filter layer thickness of 70 mm.

[0034] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics of the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. An online cleaning filter, characterized in that, The filter includes a filter body, which comprises a lower cavity and an upper cavity, with a filter screen disposed between the lower cavity and the upper cavity; the lower cavity is connected to an inlet, and a lower end cap is fixed to the bottom of the lower cavity; a lower bend pipe assembly is fixed to the outside of the lower end cap, and the lower bend pipe assembly is connected to a backwash outlet; the upper cavity is connected to an outlet, and an upper end cap is fixed to the upper part of the upper cavity; an upper bend pipe assembly is fixed to the outside of the upper end cap, and the upper bend pipe assembly is connected to a backwash inlet; The filter body axis is inclined at a 60° angle to the horizontal plane; the backwash inlet is connected to the backwash inlet and the backwash inlet pipe is set horizontally; the liquid enters the upper cavity horizontally from the backwash inlet, the liquid impacts the inner wall of the upper cavity and is reflected to the filter screen.

2. The online cleaning filter according to claim 1, characterized in that, A lower perforated plate is provided between the lower cavity and the filter screen; an upper perforated plate is provided between the upper cavity and the filter screen.

3. The online cleaning filter according to claim 2, characterized in that, A lower filter screen spacer ring is provided between the filter screen and the lower sieve plate; an upper filter screen spacer ring is provided between the filter screen and the upper sieve plate.

4. The online cleaning filter according to any one of claims 1-3, characterized in that, The filter screen is made of woven stainless steel wire.

5. A natural gas station wastewater separation and discharge system using the filter described in claim 3, characterized in that, The system includes a separator, a main process control valve, a first flushing process control valve, a second flushing process control valve, a filter, and an electric ball valve. The separator's drain outlet is connected to the filter's inlet via a first pipeline, on which the main process control valve is installed. The filter's outlet is connected to a gas field water tank via a second pipeline, on which a ball valve is installed. The separator's drain outlet is also connected to the filter's backwash inlet via a third pipeline connected to the first pipeline, on which the first flushing process control valve is installed. The filter's backwash outlet is connected to the gas field water tank via a fourth pipeline, on which the second flushing process control valve is installed.

6. The sewage system according to claim 5, characterized in that, The third pipeline connecting to the first flushing process control valve is installed vertically on the first pipeline connecting to the main process control valve.

7. The sewage system according to claim 5, characterized in that, It also includes a manual sewage discharge device. The sewage discharge port of the separator is connected to the gas field water pool through a fifth pipeline. A manual sewage discharge main valve and a manual valve sleeve sewage discharge valve are respectively installed before and after the fifth pipeline. A sampling valve is connected between the manual sewage discharge main valve and the manual valve sleeve sewage discharge valve through a pipeline.

8. A method of using the natural gas station wastewater separation system as described in claim 5, comprising the following steps: S1 Liquid Filtration: The liquid discharged from the separator enters the lower chamber of the filter through the main process control valve. Under the pressure of natural gas, the liquid passes through the lower screen plate, the lower filter screen partition ring, the filter screen, the upper filter screen partition ring and the upper screen plate, and enters the upper chamber of the filter. It then flows out from the normal production outlet and is discharged to the gas field water pool through the electric ball valve. S2 backwash: Close the main process control valve and the electric ball valve, open the first and second flushing process control valves. Under the action of natural gas pressure, the liquid enters the upper chamber through the first flushing process control valve and the backwash inlet, and then enters the lower chamber through the upper screen plate and filter screen. The liquid is discharged to the gas field water pool through the backwash outlet of the lower chamber and the second flushing process control valve.

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