CN103242924B - Tubular oil-gas separator and oil-gas separation method - Google Patents

Abstract

The invention relates to a tubular oil-gas separator and an oil-gas separation method, which are arranged in an oil-gas mixed transportation system and comprise the following steps: the liquid collecting pipe consists of an upper pipe section and a lower pipe section which are communicated; one end of the gas-liquid inlet pipe section is connected to the inlet valve group gathering pipe, and the other end of the gas-liquid inlet pipe section is connected to the inlet end of the upper pipe section; the gas-liquid outlet pipe section is connected with the outlet end of the lower pipe section; the upper pipe section is upwards communicated with an air duct, the air duct is communicated with one end of a gas liquid removal pipe, the other end of the gas liquid removal pipe is upwards communicated with a mist catcher through a pipeline, the bottom of the gas liquid removal pipe is downwards communicated with a liquid guide pipe, and the liquid outlet end of the liquid guide pipe is communicated with the lower pipe section; the upper part of the mist catcher is provided with an air outlet, the bottom of the mist catcher is provided with a liquid discharge pipe, and the liquid discharge pipe extends into the bottom of the gas liquid removal pipe. The invention provides a compact tubular oil-gas separation device, which greatly reduces the volume of the device, can be installed in the indoor edge space, cancels heat tracing and heat preservation, reduces the investment and facilitates the operation and management.

Description

A tubular oil-gas separator and oil-gas separation method

technical field

The invention relates to a surface engineering oil and gas gathering and transportation technology in oil exploitation, in particular to a fuel gas oil and gas separator and an oil and gas separation method used in a pressurized heating oil and gas mixed transportation process system.

Background technique

At present, in the process of oil and gas gathering and transportation in oilfield surface engineering, more and more pressurized heating oil and gas mixed transportation processes are used. The gas-liquid part first passes through the pump inlet manifold 2, is transported through the parallel mixed pump group 3, then enters the tubular heating furnace 5 through the furnace inlet manifold 4 for heating, and finally enters the long-distance oil-gas mixed transportation pipeline 6; A part of the natural gas separated from the oil-gas separator 1 is introduced into the tubular heating furnace 5 and used as fuel gas.

Production practice has proved that the main equipment in this process system, the parallel mixed pump unit 3 and the tubular heating furnace 5, have low operating efficiency and high failure rate, and the operation and maintenance to maintain the long-term normal operation of the system is difficult and costly. The fundamental reason is that the matching equipment is unreasonable and a scientific and reasonable configuration system has not been established. This problem exists in the use of conventional container-type oil-gas separators (as shown in Figure 5-1):

When the container-type oil-gas separator is used to separate natural gas from the oil-gas mixture and used as fuel gas for the heating furnace, due to the large volume of the container-type oil-gas separator, it has to be installed outdoors, and a heat tracing and heat preservation system needs to be installed for winter antifreeze. Cause high investment, operation and management trouble.

Contents of the invention

In order to overcome the problems existing in the container-type oil-gas separator in the current oil-gas mixed transportation process system, the purpose of the present invention is to provide a tube-type oil-gas separator that occupies a small area and can effectively separate oil and gas.

A tubular oil-gas separator provided by the present invention is installed in an oil-gas mixed transportation system, and includes a liquid collecting pipe, the liquid collecting pipe is composed of an upper pipe section and a lower pipe section respectively connected at the head end and the tail end; a gas-liquid inlet One end of the pipe section is connected to the end of the inlet valve group manifold, and the other end is connected to the inlet end of the upper pipe section; a gas-liquid outlet pipe section is connected to the outlet end of the lower pipe section; the upper pipe section communicates upward with a guide Air pipe, the air guide pipe is connected to one end of a gas liquid removal pipe, the other end of the gas liquid removal pipe is connected upwardly to a mist catcher through a pipe, and the bottom of the gas liquid removal pipe is connected to a liquid catheter downward , the liquid outlet end of the guide pipe leads to the lower pipe section; the upper part of the mist catcher is provided with an air outlet, and the bottom is provided with a liquid discharge pipe, and the liquid discharge pipe extends into the gas liquid removal pipe bottom of.

The upper pipe section and the lower pipe section are also partially communicated in the middle.

The upper pipe section and the lower pipe section are cylindrical pipes.

A liquid-removing plate is installed in the gas liquid-removing pipe, and the liquid-removing plate faces the position where the mouth of the catheter tube is located.

The liquid removal plate is made of multi-layer concentric semicircular arc-shaped stainless steel sheets.

The pipeline communicates with the inlet of the mist trap through the inlet pipe of the mist trap with a valve, and the pipeline communicates with the gas outlet through a bypass pipe of the mist trap with a valve.

A self-operated constant pressure valve is arranged on the air outlet pipe of the mist catcher.

Another object of the present invention is to provide a new oil-gas separation method.

In this oil and gas separation method, the aforementioned tubular oil and gas separator is used, the gas-liquid mixture enters from the inlet pipe section, the gas is output as fuel gas through the gas outlet, and the degassed gas-liquid mixture (sand-containing fluid) passes through the The gas-liquid outlet pipe section is discharged.

Among them, the liquid removal of natural gas includes the following process: the gas-liquid mixture enters the inlet pipe section, a part of the gas containing liquid droplets in the upper part of the inlet pipe section enters the gas liquid removal pipe through the air guide pipe, and the liquid is removed by gravity in the liquid removal pipe. After the rectification and liquid removal of the layer liquid removal plate, the gas enters the mist trap to further remove small liquid droplets, and is transported to the heating furnace through the gas outlet as fuel gas.

In the process of natural gas liquid removal, the liquid trapped in the mist trap flows into the bottom of the gas liquid removal pipe through the drain pipe at the bottom by gravity, and the liquid in the gas liquid removal pipe passes through the liquid guide pipe at the bottom by gravity Discharged into the bottom of the lower pipe section of the liquid collection pipe; the gas-liquid mixture (sand-containing fluid) entering the upper pipe section and the lower pipe section of the liquid collection pipe from the inlet pipe section together forms a gas-liquid stratified flow pattern in the liquid collection pipe, and passes through the gas-liquid The outlet pipe section is discharged and enters the next link.

When a transient long liquid plug enters the tubular oil-gas separator, the liquid collecting pipe is used to store the liquid that cannot be discharged temporarily, so as to avoid liquid entering the gas liquid removal pipe and ensure that the gas outlet can continuously supply fuel gas to the heating furnace.

With the above design, the present invention proposes a tubular oil-gas separator based on the separation principle of gas-liquid stratified flow pattern, which occupies a small area and can be used to form a gas-liquid stratified pipe flow pattern with a large enough pipe diameter. Part of the natural gas in the oil-gas mixture is efficiently separated and used as fuel for the heating furnace.

The beneficial effects it brings are:

1. The present invention provides a compact separator that is completely different from conventional container separators in terms of structure and working principle—a multi-phase tubular separator, and uses the tubular oil-gas separator as the front end of the entire oil-gas mixed transportation system Separation equipment to separate natural gas from the oil-gas mixture early, as fuel for the heating furnace, reducing the pressure drop of the subsequent pipeline system and the gas-liquid flow into the mixed booster pump, reducing the diameter of the pipeline and the pressure of the mixed pump cost.

2. The invention adopts the tubular separator, which occupies a small area, and can be placed in the pipeline laying space along the process flow in the oil-gas mixed transport pump room, without occupying additional space in the pump room, and overcomes the volume of the container-type oil-gas separator. Large size, outdoor installation, need for heat preservation, high investment, inconvenient operation and management, etc.

3. For the structure of the tubular separator itself, a separation tube composed of upper and lower pipe sections is used. The diameter of the two-layer pipe sections is determined on the condition that the gas-liquid stratified flow pattern can be formed in the pipe section. The gas-liquid inlet pipe section It is connected to the inlet end of the upper pipe section, and the gas-liquid outlet pipe section is set at the outlet end of the lower pipe section, so that the gas can be separated upward from the upper pipe section more conveniently, and the liquid part can flow away from the lower pipe section more conveniently, and the operation is stable and reliable.

Description of drawings

Figure 1 shows a process system and flow for oil and gas mixed transportation.

Figure 2 shows another oil and gas mixed transportation process system and process.

Fig. 3 is a structural diagram of the tubular oil-gas separator of the present invention.

Fig. 4 is a cross-sectional view of the liquid removal plate in the present invention.

Figure 5-1 shows the arrangement of container-type oil-gas separators in the prior art.

Figure 5-2 shows the layout of the pipe-type oil-gas separator used in the present invention.

Detailed ways

In order to make the technical solution of the present invention clearer, a specific introduction will be made below in conjunction with the accompanying drawings.

The oil-gas separator is the key supporting equipment in the oil-gas mixed transportation system. In the oil-gas mixed transportation system shown in Figure 1, a container-type oil-gas separator 1 is used. The present invention designs a tube-type oil-gas separator 7, which can replace the container Type oil-gas separator 1 is used in the system shown in Figure 1, and can also be used in the oil-gas mixed transportation system shown in Figure 2. In the oil-gas mixed transportation system shown in Figure 2, the inlet end of the pipe-type oil-gas separator 7 is connected to the manifold after the inlet valve group 8 to receive the oil-gas mixture, and part of the natural gas is separated from the oil-gas mixture as a heating furnace 9 The fuel of the tubular oil-gas separator 7 outlets is divided into two, one is the gas outlet, and the other is the gas-liquid outlet, the gas outlet is connected with the fuel inlet pipeline of the heating furnace 9, and fuel is provided to the heating furnace 9, and the gas-liquid outlet is connected with the gas-liquid outlet. The inlet pump manifold 10 is connected to further transport the oil-gas mixture to the mixed transport pump group 11, and the mixed transport pump unit 11 transports the oil-gas mixture to the heating furnace 9 through the furnace inlet manifold 12, and finally enters the long-distance oil-gas mixed transport pipeline 13 . A multiphase vibration desander 14 can also be further installed on the inlet pump manifold 10, the gas-liquid outlet is connected with the multiphase vibration desander 14, and the multiphase vibration desander 14 is connected to the mixer through the inlet pump manifold. The pump group 11 is connected. The entry valve group 8 is used to collect the oil-gas mixture produced by the oil well in the well area (the oil-gas mixture in the well area), and existing equipment can be used.

The tubular oil-gas separator 7 can also be arranged in the system as shown in FIG. 1 .

The specific structure of the tubular oil-gas separator 1 provided by the present invention is shown in FIG. Pipe 27, liquid collecting pipe 28 and gas-liquid outlet pipe section 29.

The liquid collecting pipe 28 is composed of two pipes, which are divided into an upper pipe section 28' and a lower pipe section 28", and the upper and lower pipe sections are respectively connected and collected at the head end and the tail end. One end of the gas-liquid inlet pipe section 21 is connected to the inlet valve group 1 The end of the manifold, and the other end communicates with the inlet end of the upper pipe section 28 ′ of the liquid collection pipe 28 ;

Further speaking, in the middle part of the upper pipe section 28' and the lower pipe section 28", it is also partially communicated through the vertical pipe 30.

The upper pipe section 28' communicates with the air guide pipe 22 upwards, and the air guide pipe 22 communicates with one end of the gas liquid removal pipe 23. The gas liquid removal pipe 23 is a long pipe, and a liquid removal plate 24 is installed in the pipe; the liquid removal plate 24 is a multi-layer concentric semicircular arc-shaped stainless steel sheet (as shown in FIG. 4 ). The bottom of the gas liquid removal pipe 23 faces the position of the liquid removal plate 24 and communicates with the liquid guide pipe 27 downwards, and the liquid outlet end of the liquid guide pipe 27 leads to the lower pipe section 28 " of the liquid collection pipe 28 ". The upper part of the other end of the gas liquid removal pipe 23 is connected to the mist catcher 25 through the pipe 31, the upper part of the mist catcher 25 is the gas outlet 26, and the bottom end of the mist catcher 25 is provided with a liquid discharge pipe 32 extending into the gas liquid removal pipe 23 bottom of.

Specifically, the connection structure of the pipeline 31 and the mist catcher 25 and the air outlet 26 is: as shown in Figure 3, the pipeline 31 is connected to the inlet of the mist catcher 25 through the inlet pipe 33 of the mist catcher with a valve; The mist catcher bypass pipe 34 with a valve is connected with the gas outlet 26. When the mist catcher is overhauled, the valve on this pipe is opened, and the other valves are closed, so that the gas in the gas liquid removal pipe 23 is directly output through the gas outlet 26 , to ensure uninterrupted supply of fuel gas to the furnace.

Further speaking, a small-diameter liquid discharge pipe 32 with a valve is provided at the bottom of the mist catcher, which is in a normally open state during the normal operation of the mist catcher, so that the liquid collected by the mist catcher flows to the bottom of the gas liquid removal pipe 23 by itself, so as to It is discharged through the catheter 27 into the lower section 28" of the header 28.

Furthermore, a self-operated constant pressure valve is also provided on the air outlet pipe 26 of the mist catcher 25 .

The working mode of the tubular oil-gas separator 1 is: the gas-liquid mixture enters the inlet pipe section 21, and a part of the gas containing liquid droplets in the upper part of the inlet pipe section 21 enters the gas liquid removal pipe 23 through the air guide pipe 22, and the liquid removal pipe 23 relies on gravity After settling to remove liquid, and after being rectified and liquid removed by multi-layer liquid removal plate 24, the gas enters mist catcher 25 to further remove small liquid droplets, and is transported to heating furnace 7 through gas outlet 26 as fuel gas. During the natural gas liquid removal process, the liquid trapped in the mist catcher 25 flows into the bottom of the gas liquid removal pipe 23 by gravity through the drain pipe 32 at the bottom, and the liquid in the gas liquid removal pipe 23 passes through the guide pipe at the bottom. The liquid pipe 27 is discharged into the bottom of the lower pipe section 28" of the liquid collection pipe 28 by gravity; the gas-liquid mixture (sand-containing fluid) entering the upper pipe section and the lower pipe section of the liquid collection pipe 28 from the inlet pipe section 21 is together in the liquid collection pipe 28 Form a gas-liquid stratified flow pattern, discharge through the gas-liquid outlet pipe section 29 and enter the next link. When a transient long liquid plug enters the tubular oil-gas separator, the liquid collection pipe 28 is used to store the liquid that cannot be discharged temporarily. Prevent liquid from entering the gas liquid removal pipe 23, and ensure that the gas outlet 26 can supply fuel gas to the heating furnace 7 without interruption.

The tubular oil-gas separator provided by the invention has the advantages of compact structure, small volume, easy installation, small occupied area and low investment. Figure 5-1 shows the layout of the container-type oil-gas separator used in the prior art, and Figure 5-2 shows the layout of the tube-type oil-gas separator used in the present invention. It can be seen that the present invention adopts a multi-phase pipe in the form of a pipeline structure The oil-gas separator is installed close to the wall of the pump room along the direction of the pipeline transportation process from the inlet valve group manifold to the mixing pump, so as to achieve the effect of not occupying additional space in the pump room. In the prior art, the diameter of the conventional container-type oil-gas separator is 1200-2000mm, while the diameter of the pipe-type separator is only 400-600mm, which is suitable for installation in the narrow and long corner space in the building, and is more effective than the container-type separator. The floor area is reduced by 60-70%, and the investment is reduced by 20%.

The tubular oil-gas separator provided by the invention operates stably and reliably. It meets the requirements of separating part of the natural gas from the oil-gas mixture to provide fuel gas for the heating furnace, and ensures the smooth operation of the heating furnace in the severe winter.

The above-described embodiments are only used to illustrate the present invention, wherein the structure of each component, connection mode, etc. all can be changed, and all equivalent transformations and improvements carried out on the basis of the technical solution of the present invention should not be excluded from the scope of the present invention. outside the scope of protection.

Claims (7)

1. A tubular oil-gas separator installed in an oil-gas mixed transportation system, characterized in that: comprising A liquid collecting pipe, the liquid collecting pipe is composed of an upper pipe section and a lower pipe section connected at the head end and the tail end respectively; A gas-liquid inlet pipe section, one end of which is connected to the end of the inlet manifold manifold, and the other end is connected to the inlet end of the upper pipe section; A gas-liquid outlet pipe section connected to the outlet end of the lower pipe section; The upper pipe section is upwardly connected to an air guide pipe, and the air guide pipe is connected to one end of a gas liquid removal pipe. The bottom is connected downwards with a catheter, and the outlet end of the catheter leads to the lower pipe section; A liquid removal plate is installed in the gas liquid removal pipe, and the liquid removal plate faces the position where the mouth of the catheter tube is located; The upper part of the mist catcher is provided with an air outlet, and the bottom is provided with a liquid discharge pipe, and the liquid discharge pipe extends into the bottom of the gas liquid removal pipe. 2. The tubular oil-gas separator according to claim 1, characterized in that: the upper pipe section and the lower pipe section are partially communicated in the middle. 3. The tubular oil-gas separator according to claim 2, characterized in that: the liquid removal plate is made of multi-layer concentric semicircular arc-shaped stainless steel sheets. 4. The tubular oil-gas separator according to any one of claims 1 to 3, characterized in that: the pipeline is connected to the inlet of the mist catcher through a mist catcher inlet pipe with a valve, and the pipe passes through the A mist catcher bypass pipe with a valve communicates with the gas outlet. 5. The tubular oil-gas separator according to claim 4, characterized in that: a self-operated constant pressure valve is arranged on the air outlet pipe of the mist catcher. 6. A method for oil-gas separation, characterized in that, using the tubular oil-gas separator described in any one of claims 1 to 5, the gas-liquid mixture enters from the inlet pipe section, and the gas is exported as fuel gas through the gas outlet, The degassed gas-liquid mixture is discharged through the gas-liquid outlet pipe section; specifically, the following process is included: the gas-liquid mixture enters the inlet pipe section, and a part of the gas containing liquid droplets on the upper part of the inlet pipe section enters the gas liquid removal pipe through the air guide pipe, In the liquid pipe, the liquid is removed by gravity settlement, and after rectification and liquid removal by the multi-layer liquid removal plate, the gas enters the mist collector to further remove small liquid droplets, and is transported to the heating furnace as fuel gas through the gas outlet. During this process, the gas is captured The liquid trapped in the mist device flows into the bottom of the gas liquid removal pipe by gravity through the drain pipe at the bottom, and the liquid in the gas liquid removal pipe is discharged into the lower pipe section of the liquid collection pipe by gravity through the liquid guide pipe at the bottom At the bottom of the pipe: the gas-liquid mixture entering the upper and lower pipe sections of the liquid collection pipe from the inlet pipe section together forms a gas-liquid stratified flow pattern in the liquid collection pipe, and is discharged through the gas-liquid outlet pipe section and enters the next link. 7. The oil-gas separation method according to claim 6, characterized in that, when a transient long liquid plug enters the tubular oil-gas separator, the liquid collecting pipe is used to store the liquid that cannot be drained temporarily, so as to prevent the gas from entering the liquid removal pipe. Liquid, to ensure that the gas outlet can continuously supply fuel gas to the heating furnace.