CN218862590U - Oil gas collection system - Google Patents

Abstract

The utility model discloses an oil gas collection system. The oil gas collecting device comprises a collecting tree and a pipe column, wherein the pipe column comprises an outer sleeve, a separation pipe and a liquid carrying pipe, and a liquid-gas separation cavity, a communication cavity and a liquid carrying cavity are formed; the bottom of the communicating cavity is closed; the lower opening of the middle hole of the liquid carrying pipe is communicated below the liquid level in the well; a gas-liquid mixing chamber is arranged in the liquid carrying cavity; in the collection tree, the gas-liquid outlet is communicated with the liquid carrying cavity, the liquid-gas separation cavity is communicated with the first bypass hole, and the communication cavity is communicated with the second bypass hole; the two bypass holes are communicated with each other and introduce gas into the communicating cavity; the gas-liquid mixing chamber is communicated with the communicating cavity through the gas distribution holes in the pipe wall of the liquid carrying pipe. In the well opening and closing processes, the gas-liquid mixing chamber is communicated with the communicating cavity through the gas distribution hole; the gas entering the communicating cavity enters the gas-liquid mixing chamber through the gas distribution holes in the pipe wall of the liquid carrying pipe. Form gas-liquid mixture in the gas-liquid mixing room, the liquid pipe diameter is taken in the matching, and the performance is taken the liquid ability, avoids the liquid column slug to form, avoids the liquid column slug to produce adverse effect.

Description

Oil gas collection system

Technical Field

The utility model relates to an hydrops discharge technology in oil gas field and coal bed gas exploitation field especially relates to an oil gas collection system.

Background

In the process of exploiting oil and gas fields and coal bed gas, liquid accumulated in a shaft is one of the main problems which restrict the stable production and the high production of oil and gas wells. In order to ensure normal production of oil wells and gas wells, accumulated liquid in a shaft needs to be drained in time, particularly high-yield wells. The accumulated liquid can not be discharged in time, which will seriously affect the oil gas output, resulting in low output ratio of the oil gas well and poor economic benefit. This requires that the wellbore fluid be drained in a suitable manner.

The current liquid discharge oil gas production technology has the following great application amount: bubble drainage liquid-carrying gas production technology, plunger drainage gas production technology and the like. The main relative disadvantages of these techniques are that they have a small liquid carrying capacity and poor liquid carrying capacity, and are only suitable for gas wells with small liquid production volumes, but not for gas wells with high liquid production volumes.

The technology suitable for high-yield liquid gas wells mainly comprises the following steps: the pump drainage, the electric submersible pump drainage, the screw pump drainage and the like are adopted, but the most defects of the technologies are that the maintenance is frequent due to the complex structure and the need of maintaining underground equipment, the maintenance is needed about 1 year, and the maintenance cost is high; meanwhile, frequent maintenance causes great influence on oil and gas reservoirs, the difficulty in recovering the production of the gas well after maintenance is high, the output ratio of the gas well is reduced, and the cost recovery is difficult or slow.

Because the small-diameter pipeline (small-diameter pipe for short) has better liquid carrying capacity, but because the pipe diameter is smaller, liquid with the same volume is easier to form a liquid column slug in the small-diameter pipe, and the friction resistance of the liquid column slug is larger, so that the accumulated liquid moves up slowly; because of the residual liquid in the pipe diameter, the accumulated liquid slowly moves upwards and accumulates the height of the existing liquid column in the small-diameter pipe, and the liquid discharge quantity of the small-diameter pipe is further reduced. Therefore, the function of the small-diameter pipe with better liquid drainage performance is seriously influenced, the well opening time is shortened, the well closing time is prolonged, and the yield of the oil-gas well is influenced.

Therefore, how to solve the unfavorable problem of the small-diameter pipe liquid column slug and exert the advantage of the small-diameter pipe with better liquid carrying capacity becomes a technical problem to be solved urgently by technical personnel in the field.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a first purpose provides an oil gas collection system utilizes this oil gas collection system, can solve the unfavorable problem of minor diameter pipe liquid column slug, and the better advantage of liquid ability is taken to performance minor diameter pipe, improves flowing back efficiency.

The utility model provides an oil gas collecting device, which comprises a collecting tree and a pipe column, wherein the pipe column comprises an outer sleeve, a separation pipe and a liquid carrying pipe which are arranged from outside to inside; a liquid-gas separation cavity communicated below the liquid level in the well is formed between the outer sleeve and the separation pipe, a communication cavity is formed between the separation pipe and the liquid carrying pipe, and a liquid carrying cavity is formed in the liquid carrying pipe; the bottom of the communicating cavity is closed; the lower opening of the middle hole of the liquid carrying pipe is communicated below the liquid level in the well; at least one gas-liquid mixing chamber is arranged in the liquid carrying cavity; the collecting tree is provided with a gas-liquid outlet, a first bypass hole and a second bypass hole, the gas-liquid outlet is communicated with the liquid carrying cavity, the liquid-gas separation cavity is communicated with the first bypass hole, and the communication cavity is communicated with the second bypass hole; the second bypass hole is communicated with the first bypass hole, and gas in the liquid-gas separation cavity is introduced into the communication cavity; the gas-liquid mixing chamber is communicated with the communicating cavity through the gas distribution holes in the pipe wall of the liquid carrying pipe.

Therefore, in the process of opening or closing the well, gas and liquid produced by the oil-gas reservoir are gathered in the liquid-gas separation cavity, and hundreds of meters or thousands of meters can exist in the depth of the liquid-gas separation cavity, so that a larger space is formed; in the liquid-gas separation chamber, the gas moves upwards due to the large difference between the densities of the gas and the liquid, and the liquid is deposited at the bottom to form the gas-liquid separation. The gas-liquid mixing chamber is communicated with the communicating cavity through a gas distribution hole in the pipe wall of the liquid carrying pipe, and the bottom of the communicating cavity is closed; therefore, the gas entering the communicating cavity can enter the gas-liquid mixing chamber through the gas distribution holes in the pipe wall of the liquid carrying pipe. Meanwhile, the lower opening of the middle hole of the liquid carrying pipe is communicated to the position below the underground liquid level, liquid can enter the gas-liquid mixing chamber through the liquid carrying pipe, a gas-liquid mixture with the optimal gas-liquid ratio is formed in the gas-liquid mixing chamber, the pipe diameter of the liquid carrying pipe is matched, the liquid carrying capacity of the liquid carrying pipe is exerted, and liquid discharge operation or oil and gas collection is implemented. Through gas distribution hole with take the liquid pipe can control the gas-liquid ratio, and then avoid the formation of liquid column slug, and then avoid the adverse effect that liquid column slug produced, realize the utility model discloses a purpose.

In a preferable technical scheme, a throttling device is arranged between the second bypass hole and the first bypass hole, and the throttling device can control and distribute certain gas flow, reduce or avoid the formation of a liquid column slug, or control and implement constant flow production.

In a further technical scheme, the first bypass hole is communicated with the gas-liquid outlet through an on-off control valve. Therefore, when the well is closed, the first bypass hole and the gas-liquid outlet channel can be communicated by opening the on-off control valve, so that pressurized gas formed by separating the liquid-gas separation cavity directly enters the liquid carrying cavity, residual liquid or solid particles in the liquid carrying cavity can be discharged downwards, and the small-diameter liquid carrying pipe can be cleaned; the cleaning operation is carried out, convenience is provided for next circulation well opening and liquid carrying, and the reliability of well opening and liquid carrying is improved. Of course, an on-off valve may be disposed in the first intermediate passage to control the on-off of the first intermediate passage.

It can be understood that the on-off control valve and the communication pipeline thereof can be arranged according to the requirement of the well condition, or the on-off control valve is not arranged.

After the first bypass hole and the gas-liquid outlet on-off control valve are closed, a one-way conduction valve from the first bypass hole to the second bypass hole can be arranged between the second bypass hole and the first bypass hole; therefore, an external air source can be additionally arranged at the outer end of the throttling device or the position near the air inlet side of the throttling device, and the liquid carrying effect is improved. After the on-off control valve is opened and switched on, or external gas and liquid can be introduced into the liquid carrying cavity to clean residual liquid, bonded or deposited solid particles.

In a preferable technical scheme, the liquid carrying cavity of the liquid carrying pipe and a communication pipeline below the underground liquid level are provided with liquid distribution holes for liquid passing in a fixed proportion, liquid entering the liquid carrying cavity is controlled, and the formation of a gas-liquid mixture with an optimal gas-liquid ratio is guaranteed.

In a further technical scheme, the liquid-gas separation cavity is communicated with the liquid carrying cavity through a second intermediate channel, and the communication position of the second intermediate channel and the liquid-gas separation cavity is positioned above the liquid level in the well, so that gas in the liquid-gas separation cavity is introduced into the liquid carrying cavity; and an on-off valve is arranged in the second middle channel to control the on-off of the second middle channel. Therefore, when the well is closed, the second middle channel can be conducted, so that pressurized gas formed by the separation of the liquid-gas separation cavity can directly enter the liquid carrying cavity; discharging the residual liquid or solid particles in the liquid carrying cavity Y3 downwards to clean the small-diameter liquid carrying tube, namely performing cleaning operation; the convenience is provided for the next circulation of opening the well and carrying the liquid, and the reliability of opening the well and carrying the liquid is improved. Of course, an on-off valve may be provided in the first intermediate passage to control the on-off of the first intermediate passage.

In a further technical scheme, the tubular column of the oil-gas acquisition device further comprises a liquid passing pipe section and a liquid passing pipe; the liquid passing pipe section is connected to the lower end of the liquid carrying pipe, and a cleaning channel is formed in the liquid passing pipe section; the lower part of the cleaning channel is provided with a limiting bulge to limit the limit position of the lower part of the liquid passing pipe.

The outer diameter of the liquid passing pipe is smaller than the inner diameter of the cleaning channel, the upper end face of the liquid passing pipe is in sealing fit with the liquid carrying pipe, and the liquid passing hole in the liquid passing pipe corresponds to the middle hole of the liquid carrying pipe. Spacing arch with take the spacing distance of terminal surface to be greater than under the liquid pipe height of crossing can make liquid pipe 141 reciprocate suitable distance at clean passageway.

In a preferred technical scheme, the liquid passing holes can also be of a preset size, and the liquid passing holes with a fixed proportion are formed so as to control the liquid flow rate passing through the liquid passing holes.

Therefore, when the well is opened for liquid drainage, the liquid in the lower part can flow upwards from bottom to top through the middle hole, and meanwhile, the liquid flowing from bottom to top can push the liquid passing pipe to move upwards, so that the upper end surface of the liquid passing pipe is in sealing fit with the lower end surface of the liquid carrying pipe. The liquid passing hole of the liquid passing pipe corresponds to the middle hole of the liquid carrying pipe; in a more preferable technical scheme, the inner diameter of the liquid passing hole of the liquid passing pipe is smaller than the inner diameter of the liquid carrying pipe to form quantitative matching so as to control the liquid passing amount.

When the well is closed for cleaning operation, the pressure gas separated by the liquid-gas separation cavity enters the liquid carrying cavity through the second middle channel, carries residual liquid or adhered or deposited solid particles carrying the liquid carrying cavity to move from top to bottom, pushes the liquid passing pipe to move downwards, releases the sealing between the upper end surface and the lower end surface of the liquid carrying pipe, and enables the residual liquid or adhered or deposited solid particles to smoothly fall from the liquid passing pipe and larger space around the liquid passing pipe, thereby improving the cleaning operation effect.

In a further technical scheme, the inner wall of the upper end or/and the inner wall of the lower end of the cleaning channel is/are provided with guide convex ribs, and the guide convex ribs are matched with the outer peripheral surface of the liquid passing pipe, namely in sliding fit in the up-down direction. Therefore, the liquid passing pipe can be ensured to go upward and be sealed smoothly, and the set liquid inlet amount can be effectively controlled.

In a further technical scheme, the tubular column of the oil-gas acquisition device further comprises a limiting short connecting pipe; the lower end surface of the liquid passing pipe section is in sealing fit with the upper end surface of the limiting short connecting pipe; the limiting short connecting pipe is connected with the lower end of the separating pipe.

Thus, when the underground installation is carried out, the outer sleeve can be firstly lowered to the bottom N of the well, then the separating pipe with the lower end fixed with the limiting short connecting pipe is lowered to a preset position in the outer sleeve, for example, the lower end of the limiting short connecting pipe reaches the position below the underground liquid level; then, in the separation tube, a liquid carrying tube (small-diameter tube) with a liquid passing tube section fixed at the lower end is put into the well, the lower end face of the liquid passing tube section is in contact with the upper end face of the limiting short connecting tube to form sealing fit, and the liquid carrying tube and the separation tube are sealed at the lower end below the liquid level in the well to form a communicating cavity and are sealed and isolated from the lower part of the liquid-gas separation cavity.

It will be appreciated that the separating tube or/and the liquid carrying tube may be a continuous conduit. Wherein, the separating tube and the liquid carrying tube can also be an integrated continuous tube. The separation tube and the lower end of the liquid carrying tube can also implement the sealing mode and the structure with the same technical effect

The middle hole of the limiting short connecting pipe is communicated with the liquid passing hole of the liquid passing pipe section, so that the smooth passage and the smooth flowing (upward or downward) of liquid, gas or solid can be ensured during liquid discharging operation or cleaning operation.

It can be understood that the lower end surface of the liquid carrying pipe and the upper end surface of the limit nipple can form sealing fit; the limiting short connecting pipe is connected with the lower end of the separating pipe, and the middle hole of the limiting short connecting pipe is communicated with the middle hole of the liquid carrying pipe, so that the same technical effects can be generated.

It can be understood that the middle hole of the limiting nipple can also implement the structure and the function of the liquid passing hole or the structure and the function of the liquid passing pipe according to the requirement.

In a preferred technical scheme, the gas-liquid mixing chamber comprises a conical cavity with the radius gradually increasing from bottom to top, and the center line of the conical cavity is superposed with the center line of the liquid carrying cavity; the gas distribution hole comprises a plurality of proportional vent holes, and the openings of the proportional vent holes are uniformly distributed around the center line of the liquid carrying cavity. The air vent opening evenly arranged in the fixed proportion is favorable for promoting gas-liquid evenly mixed, and the conical cavity with the radius gradually increased from bottom to top can promote gas-liquid mixed, guarantees to carry the homogeneity of gas mixture in the liquid pipe, guarantees to carry the liquid carrying capacity and the liquid carrying stability of liquid pipe.

In the preferred technical scheme, a liquid hole is arranged in the liquid carrying pipe in a fixed proportion, and the liquid enters the gas-liquid mixing chamber through the liquid hole in the fixed proportion, so that the matching precision of liquid distribution can be ensured.

In the preferred technical scheme, the fixed-proportion vent holes and/or the fixed-proportion liquid passing holes and/or the liquid passing holes can be formed by scouring-resistant alloy, so that the gas/liquid distribution precision can be ensured, and the service life is prolonged.

In a preferred technical scheme, the fixed-proportion vent hole is sealed by a fixed-pressure rupture sheet. Like this, when the tubular column went into the well to the design position installation, can make and carry between liquid chamber and the intercommunication chamber sealed, and then can test whether the intercommunication chamber reaches predetermined sealed condition. After the communication cavity is determined to reach the sealing condition, pressure exceeding the pressure born by the constant pressure rupture sheet can be applied to rupture the constant pressure rupture sheet, the constant proportion vent hole is unsealed, and the liquid carrying cavity and the communication cavity are communicated through the constant proportion vent hole to carry out liquid drainage operation.

In the preferred technical scheme, the tubular column of the oil-gas acquisition device further comprises a liquid inlet sand control pipe connected with the separation pipe; the middle hole of the liquid inlet sand control pipe is communicated with the middle hole of the liquid carrying pipe, and the pipe wall of the liquid inlet sand control pipe is provided with sieve meshes communicated with the inside and the outside. Like this, when liquid pipe was taken in the liquid entering, just need get into through the sieve mesh of feed liquor sand control pipe, and then realize the filtration to liquid, reduce the adverse or other influences that the particulate matter carried liquid, improve and take liquid pipe to take liquid ability.

In a preferable technical scheme, the tubular column of the oil-gas collecting device further comprises a liquid-gas collecting sleeve positioned outside the liquid inlet sand control pipe; the upper end of the liquid-gas collecting sleeve is relatively fixed with the liquid inlet sand control pipe, the lower end of the liquid-gas collecting sleeve is open, and the inner wall surface of the liquid-gas collecting sleeve at least corresponds to part of the sieve pores. Liquid gas is collected the sleeve and can be increased partial gas and pass through the sieve mesh entering along with liquid and take the liquid pipe, close the more gaseous entering of well in-process gathering take the liquid pipe, reduce relatively take the liquid column height when the intraductal open-hole that takes, the next circulation of being convenient for is opened the well and is taken liquid.

In the preferred technical scheme, the tubular column of the oil-gas acquisition device further comprises a sand discharge valve section and a sand discharge valve plug; the sand discharge valve section is connected to the lower end of the liquid inlet sand control pipe, and a sand discharge channel is formed in the sand discharge valve section; a sand discharge limiting bulge is formed at the lower part of the sand discharge channel; the spacing distance between the sand discharge spacing bulge and the lower end face of the inner boss of the liquid inlet sand prevention pipe is larger than the height of the sand discharge valve plug, so that the sand discharge valve plug can move up and down for a proper distance in the sand discharge channel; the upper end surface of the sand discharge valve plug is in sealing fit with the lower end surface of the inner boss of the liquid inlet sand prevention pipe.

Therefore, when liquid drainage operation is carried out, the sand discharge valve plug has different upper and lower pressures, so that the sand discharge valve plug moves upwards, the upper end surface of the sand discharge valve plug is in sealing fit with the lower end surface of the inner boss of the liquid inlet sand control pipe, and liquid cannot enter the liquid inlet sand control pipe from the lower end surface of the liquid inlet sand control pipe but only enters the liquid inlet sand control pipe through a sieve mesh; when cleaning operation is carried out, the pressurized gas, the residual liquid or the fixed particles push the sand discharge valve plug to move downwards from top to bottom, and the sealing between the upper end face of the sand discharge valve plug and the lower end face of the inner boss of the liquid inlet sand control pipe is released. Because the outer diameter of the sand discharge valve plug is smaller than the inner diameter of the sand discharge channel, a larger sand discharge circulation space is formed around the sand discharge valve plug.

In the preferred technical scheme, the lower terminal surface that the sand discharge valve was stifled has the liquid breach, perhaps forms corresponding clearance between the lower terminal surface that the sand discharge valve was stifled and the spacing arch of sand discharge, and then makes things convenient for raffinate or fixed granule etc. to discharge, fall into the shaft bottom through above-mentioned through-flow space, guarantees right carry the clean effect of liquid pipe.

In a further technical scheme, in the oil and gas acquisition device, a throttling device is arranged between the second bypass hole and the first bypass hole. Through throttling arrangement, can control from the gas of liquid-gas separation chamber exhaust, match the gas liquid volume adaptation better carry the liquid pipe, realize the best liquid effect of carrying, can control the stratum exploitation simultaneously, fully protect the stratum, the extension exploitation time to realize the best economic benefits of gas well.

In a further technical scheme, a one-way conduction valve from the first bypass hole to the second bypass hole is arranged between the second bypass hole and the first bypass hole. When utilizing external air supply, can avoid getting into liquid-gas separation chamber through first by pass hole, can utilize external air supply to get into through intercommunication chamber, gas distribution hole, gas-liquid mixing room and take the liquid chamber, increase and take the liquid effect.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary, features, and aspects of the present invention, and together with the description, serve to explain the principles of the invention.

FIG. 1 is a schematic view of an assembly structure of an embodiment of an oil and gas collection device;

FIG. 2 is a schematic diagram illustrating the working principle of the oil and gas collection device in liquid discharge operation when a well is opened;

FIG. 3 is a schematic view of the working principle of the oil and gas collection system performing a cleaning operation when the well is shut in;

fig. 4 is a schematic diagram of a specific structure of the pipe column (the pipe column is illustrated by way of omission) in the embodiment of the present invention;

FIG. 5 is an enlarged view of a portion A1 in FIG. 4, which illustrates a specific structure that gas in the liquid-gas separation chamber Y1 enters the liquid carrying chamber Y3 and then is mixed with liquid in the liquid carrying chamber Y3 to form a gas-liquid mixture with a suitable ratio;

FIG. 6 is an enlarged view of portion A2 of FIG. 4, illustrating the configuration of the flow-through section;

FIG. 7 is an enlarged view of a portion A3 in FIG. 4, mainly illustrating the structure of the sand discharge valve section;

FIG. 8 is an enlarged view of portion A4 of FIG. 4, mainly illustrating the structure of the sand discharge valve section;

FIG. 9 illustrates the structure of the above-ground portion of the oil and gas collection device, mainly the collection tree portion;

FIG. 10 shows the structure of the combination of the tree and the string.

Wherein, in the figure:

the device comprises a pipe column 100, an outer sleeve 110, a separation pipe 120, a liquid carrying pipe 130, a gas-liquid mixing chamber 131, a gas distribution hole 132, a liquid passing pipe section 140, a liquid passing pipe 141, a cleaning channel 140a, a limiting bulge 140b, a guide convex rib 140c, a liquid passing hole 140d, a limiting short connecting pipe 150, a liquid inlet sand prevention pipe 160, a sieve hole 161, a liquid-gas collecting sleeve 163, a sand discharge valve section 170, a sand discharge valve plug 171, a sand discharge channel 170a and a sand discharge limiting bulge 170b;

the collecting tree comprises a collecting tree 200, a lower four-way piece 25, a three-way pipe 28, an upper connecting piece 21, a pipeline coupling 14, a pipeline short connector 15, a connector 16, a small four-way 39, a collecting pipeline valve 41, a one-way conduction valve 223, a connector pressing cap 18, an overflowing connector 19, a first bypass hole 221, a throttling device 222, a throttling protection device 31, a collecting drain pipe 210, a gas-liquid outlet 211, a first bypass hole pipeline 220, an on-off control valve 224, a bypass pipe 230, a second bypass hole 231,

The liquid-gas separation cavity Y1, the communicating cavity Y2 and the liquid carrying cavity Y3;

the bottom N, the ground P and the underground liquid level M.

Detailed Description

Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated. The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present invention. It will be understood by those skilled in the art that the present invention may be practiced without some of these specific details. In some instances, methods, means, elements well known to those skilled in the art have not been described in detail so as not to obscure the present invention.

In this document, unless otherwise indicated or otherwise indicated by context, the terms "inner," "outer," "end," "upper," "lower," and the like are used to refer to the central axis of the hydrocarbon collection device string. In this section, for the sake of brevity and also for facilitating understanding of those skilled in the art, the embodiments of the oil and gas collecting apparatus provided by the present invention are described while describing the embodiments of the pipe column thereof, and when describing the working principle, the embodiments of the oil and gas collecting method are described. The pipe string and the oil and gas collection method are not separately described.

Referring to fig. 1 and 2, fig. 1 is a schematic view of an assembly structure of an oil and gas collecting device, and fig. 2 is a schematic view illustrating a working principle of a liquid discharging operation of the oil and gas collecting device when a well is opened. In fig. 1 and 2, the string is illustrated by way of omission and does not represent the actual scale of the tree to the string. In practice, the pipe string may extend several hundred or several thousand meters below the ground surface, and in the up-down direction, the pipe string may be formed of multiple sections, which may be connected by corresponding pipe joints; or metal pipes or non-metal pipes are connected or connected in the existing mode. The tubing string may also be formed of continuous tubing. Wherein the separation pipe and the liquid carrying pipe can be an integrated continuous pipeline.

As shown in fig. 1 and 2, the hydrocarbon collection device includes a tubular string 100 and a collection tree 200. The main body of the string 100 is located at the lower surface and the main body of the tree 200 is located at the upper surface.

As shown in fig. 2, the tubing string 100 includes an outer casing 110, a spacer tube 120, and a fluid carrying tube 130 disposed from the outside to the inside. The outer sleeve 110 is arranged to the bottom N of the well, and a gas-liquid inlet channel communicated with the stratum is arranged near the bottom N of the well, so that pressure gas-liquid of a stratum oil-gas reservoir can conveniently enter an inner cavity of the outer sleeve 110, and a relatively closed space is formed inside the outer sleeve. The spacer tube 120 descends into the outer sleeve 110. A liquid carrying tube 130 is run down the well from the separator tube 120. The separation tube 120 and the liquid carrying tube 130 may be separate or integrated continuous tubes, and may be simultaneously inserted into the outer sleeve 110.

The outer sleeve 110 and the separating tube 120 form a liquid-gas separation cavity Y1 communicated below the liquid level in the well. In the process of opening or closing the well, gas and liquid produced by the oil-gas reservoir are gathered in the liquid-gas separation cavity Y1, and the liquid-gas separation cavity Y1 is hundreds of meters or thousands of meters deep, so that a large space is formed; in the liquid-gas separation chamber Y1, since the density difference between the gas and the liquid is large, the gas and the liquid are automatically separated, the gas moves upward, and the liquid is deposited at the bottom, thereby realizing the gas-liquid separation.

A communication cavity Y2 is formed between the separation tube 120 and the liquid carrying tube 130. A liquid carrying cavity Y3 is formed in the liquid carrying tube 130. At least one gas-liquid mixing chamber 131 (see the following description and fig. 5 for specific structure) is disposed in the liquid carrying cavity Y3, the gas-liquid mixing chamber 131 is communicated with the communicating cavity Y2 through a gas distribution hole 132 in the tube wall of the liquid carrying tube 130, and the bottom of the communicating cavity Y2 is closed.

The liquid-gas separation cavity Y1 is communicated with the communicating cavity Y2 through a proper first intermediate channel, and the communicating part of the first intermediate channel and the separation cavity Y1 is positioned above the liquid level in the well. Thus, the gas of the liquid-gas separation chamber Y1 can be introduced into the communication chamber Y2; the gas entering the communication cavity Y2 can enter the gas-liquid mixing chamber 131 through the gas distribution holes 132 in the tube wall of the liquid carrying tube 130; meanwhile, the lower opening of the middle hole of the liquid carrying pipe 130 is communicated below the liquid level in the well, liquid can enter the gas-liquid mixing chamber 131 through the liquid carrying pipe 130, a gas-liquid mixture with the optimal gas-liquid ratio is formed in the gas-liquid mixing chamber 131, the pipe diameter of the liquid carrying pipe is matched, the liquid carrying capacity of the liquid carrying pipe 130 can be exerted, and the liquid discharge collection operation is realized.

Like this, can control the gas-liquid ratio through gas distribution hole 132 and take liquid pipe 130, and then avoid the formation of liquid column slug, avoid the adverse effect that the liquid column slug produced, realize the utility model aims at. The specific gas-liquid ratio can be adjusted based on the pipe diameter of the liquid carrying pipe 130 according to actual needs. It is understood that, in order to ensure the liquid carrying capability of the liquid carrying tube 130, the inner diameter thereof may be between 4 mm and 150 mm, and may be 6 mm, 12 mm, 33 mm, 40 mm, etc.

Further, the first channel of the collection tree is provided with the throttling device 222, the size of a throttling valve port is adjusted, the gas liquid amount is better matched to be suitable for the liquid carrying pipe to carry liquid, the best liquid carrying effect is achieved, or the implementation of fixed flow production is controlled, the stratum exploitation can be controlled, the stratum is fully protected, the exploitation time is prolonged, and the best economic benefit of a gas well is achieved.

As shown in FIG. 3, FIG. 3 illustrates a schematic diagram of the operation of the hydrocarbon recovery device in a clean-up operation when the well is shut in. The liquid-gas separation cavity Y1 is communicated with the liquid carrying cavity Y3 through a proper second intermediate channel, the second intermediate channel is communicated with the liquid-gas separation cavity Y1 and is positioned above the underground liquid level, and the gas of the liquid-gas separation cavity Y1 is introduced into the liquid carrying cavity Y3. And an on-off valve can be arranged in the second middle channel to control the on-off of the second middle channel.

Therefore, when the well is closed, the second middle channel can be conducted, and pressurized gas formed by the separation of the liquid-gas separation cavity Y1 directly enters the liquid carrying cavity Y3; thereby pushing the residual liquid or solid particles in the liquid carrying cavity Y3 downwards to clean the small-diameter liquid carrying tube 130, namely, performing cleaning operation; the convenience is provided for the next circulation of opening the well and carrying the liquid, and the reliability of opening the well and carrying the liquid is improved. Of course, an on-off valve may be disposed in the first intermediate passage to control the on-off of the first intermediate passage, so as to facilitate installation, maintenance or other operations.

It can be understood that the on-off control valve and the communication pipeline thereof can be arranged according to the requirement of the well condition or not.

As shown in fig. 4 and 5, fig. 4 is a schematic view of a specific structure of a pipe column in an embodiment of the present invention. The column is indicated by omitting; fig. 5 is an enlarged view of a portion A1 in fig. 4, which illustrates a specific structure that gas in the liquid-gas separation chamber Y1 enters the liquid carrying chamber Y3 and then is mixed with liquid entering the liquid carrying chamber Y3 to form a gas-liquid mixture with a suitable ratio. In this embodiment, the gas-liquid mixing chamber 131 is formed in the liquid carrying pipe 130, and includes a conical cavity with a radius gradually increasing from bottom to top, and a center line of the conical cavity coincides with a center line of the liquid carrying cavity Y3; the gas distribution holes 132 include a plurality of proportional air vents, and the openings of the proportional air vents are uniformly arranged around the center line of the liquid carrying cavity Y3. The openings of the proportional vent holes are uniformly distributed, so that the gas and the liquid are uniformly mixed, and the liquid carrying stability of the liquid carrying pipe 130 is ensured. As shown in fig. 5, a liquid-passing hole 133 with a fixed ratio is disposed in the liquid-carrying tube 130, and the liquid enters the gas-liquid mixing chamber 131 through the liquid-passing hole 133 with a fixed ratio, so that the matching precision of liquid distribution can be ensured.

It will be appreciated that the proportional air vent and/or proportional liquid drain 133 may be formed of a flush resistant alloy, which may ensure gas/liquid dispensing accuracy and extend service life. The proportional ventilation holes and/or proportional weep holes 133 may be formed of a erosion-resistant alloy tube, a coating of erosion-resistant alloy may be formed in the appropriate tube bore, or the portions shown in fig. 5 may be made of an erosion-resistant alloy.

In this embodiment, the proportional air vent may be sealed with a constant pressure rupture disc prior to downhole installation. Thus, when the pipe column is installed in a well, the liquid carrying cavity Y3 and the communication cavity Y2 can be sealed. It is further possible to test whether the communication chamber Y2 has reached a predetermined sealing condition by pressurizing above the ground. After the communication cavity Y2 is determined to reach the sealing condition, the pressure exceeding the pressure born by the constant pressure rupture sheet can be applied to rupture the constant pressure rupture sheet, the constant proportion vent hole is unsealed, and the liquid carrying cavity Y3 and the communication cavity Y2 are communicated through the constant proportion vent hole to carry out liquid drainage operation. It will be appreciated that the pressure to which the constant pressure rupture disc is subjected should be greater than the maximum pressure at which the communication chamber Y2 is tested for gas tightness.

Fig. 6 is an enlarged view of a portion A2 of fig. 4, which illustrates the structure of the liquid passing pipe section, as shown in fig. 6. In this embodiment, the column further comprises a liquid passing section 140 and a liquid passing tube 141 located inside the liquid passing section 140; the liquid-carrying pipe section 140 is connected to the lower end of the liquid-carrying pipe 130, and a cleaning channel 140a is formed inside the liquid-carrying pipe section; the cleaning passage 140a is formed with a limiting protrusion 140b at the lower portion thereof to limit the limit position of the lower portion of the liquid passing pipe 141. As shown in the figure, the outer diameter of the liquid passing tube 141 is smaller than the inner diameter of the cleaning channel 140a, the upper end surface of the liquid passing tube is in sealing fit with the lower end surface of the liquid carrying tube 130, and the liquid passing hole 140d inside the liquid passing tube 141 corresponds to the middle hole of the liquid carrying tube 130. The distance between the limiting protrusion 140b and the lower end surface of the liquid carrying tube 130 is greater than the height of the liquid passing tube 141, so that the liquid passing tube 141 can move up and down by a proper distance in the cleaning channel 140 a.

Thus, in the process of opening the well, when the liquid drainage collection operation is performed, the liquid at the lower part can flow upwards through the middle hole from bottom to top, and the liquid passing pipe 141 can be pushed to move upwards, so that the upper end surface of the liquid passing pipe and the lower end surface of the liquid carrying pipe are kept in sealing fit. The liquid passing hole 140d of the liquid passing pipe 141 corresponds to the middle hole of the liquid carrying pipe 130, so that accurate liquid passing control is realized. In a more preferable technical scheme, the inner diameter of the liquid passing pipe 141 is smaller than that of the liquid carrying pipe 130, and the liquid can be passed in a fixed proportion.

When the well is closed, cleaning operation is carried out, when the pressure gas carries residual liquid or adhered or deposited solid particles to move from top to bottom, the liquid passing pipe 141 is pushed to move downwards, the upper end face of the liquid passing pipe is unsealed with the lower end face of the liquid carrying pipe, the residual liquid or the adhered or deposited solid particles can fall smoothly from a larger space around the liquid passing pipe 141, and the cleaning operation effect is improved.

It can be understood that outer grooves can be formed on the outer surface of the liquid passing pipe 141, and the outer grooves can be non-closed rings, so that the liquid passing pipe can move upwards smoothly when a well is opened, or can move downwards when the well is closed, and solid particles are difficult to block.

Fig. 6 is an enlarged view of a portion A2 of fig. 4, which illustrates the structure of the liquid passing pipe section, as shown in fig. 6. In this embodiment, the inner wall of the upper end or/and the inner wall of the lower end of the cleaning channel 140a is provided with a guiding rib 140c, and the guiding rib 140c is engaged with the outer circumferential surface of the liquid flowing pipe 141, i.e. is slidably engaged in the vertical direction. Thus, the accuracy of the liquid passing through the liquid passing pipe 141 in a fixed proportion can be ensured.

Referring to fig. 4 again, in this embodiment, the tubular column of the oil-gas collecting device further includes a limit nipple 150; the lower end surface of the liquid passing pipe section 140 is in sealing fit with the upper end surface of the limiting short connecting pipe 150; the stopper nipple 150 is connected to the lower end of the separation tube 120. In the downhole installation, the outer casing 110 may be lowered to the bottom of the well N, and then the separation tube 120 with the lower end fixed to the limit nipple 150 may be lowered to a predetermined position in the outer casing 110, for example, the lower end of the limit nipple 150 may reach below the liquid level in the well. Then, in the separation tube 120, the liquid carrying tube 130 (small diameter tube) with the lower end fixed with the liquid passing tube section 140 is put into the well, the lower end face of the liquid passing tube section 140 is contacted with the upper end face of the limit nipple 150 to form sealing fit, and the lower end of the liquid carrying tube 130 and the separation tube 120 is sealed and closed under the liquid level in the well to form a communication cavity and is sealed and isolated from the lower part of the liquid-gas separation cavity. Meanwhile, the middle hole of the limiting nipple 150 is communicated with the liquid passing hole 140d of the liquid passing pipe section 140, so that liquid, gas or solid can smoothly flow (upwards or downwards) during the liquid discharge collection operation or the cleaning operation.

It is understood that the separator tube 120 and/or the liquid carrying tube 130 may be a continuous tube. The separation tube 120 and the liquid carrying tube 130 may also be an integrated continuous tube. The lower end of the continuous pipe can also implement the sealing mode and the structure of the same technical function.

It is understood that the liquid-carrying tube 130 has no liquid-carrying tube 141 in the liquid-carrying tube section 140, and only has a cleaning channel, which is communicated with the central hole of the liquid-carrying tube, and the technical effect of gas-liquid distribution can also be produced.

It can be understood that when the liquid passing pipe section 140 and the liquid passing pipe 141 are omitted, the lower end surface of the liquid carrying pipe 130 can be in sealing fit with the upper end surface of the limiting nipple 150; and the spacing nipple 150 is connected to the lower end of the separation tube 120, and the middle hole thereof is communicated with the middle hole of the liquid carrying tube 130, which can also produce substantially the same technical effects.

According to the above description, in the present embodiment, the limiting short pipe 150 is connected to the lower end of the separation pipe 120 in a screw-sealing manner, and the upper end of the limiting short pipe 150 is in sealing engagement with the lower end surface of the liquid passing section 140 or the lower end surface of the liquid carrying pipe 130, so as to seal the lower end of the communication cavity Y2. Of course, as required, can be sealed the lower extreme of intercommunication chamber Y2 (if set up the sealing ring, seal cover other hard seal, soft seal, or other positions set up sealed fitting surface etc.) by other modes, as long as its sealed position is less than gas distribution hole 132, just can take liquid chamber 130 through the gaseous introduction of intercommunication chamber Y2 with the separation, block that liquid passes through gas distribution hole 132 and get into, realize the utility model aims at.

It is understood that the separator tube 120 and/or the liquid carrying tube 130 are continuous conduits. Wherein, the separating tube and the liquid carrying tube are a continuous tube which is integrated. The lower ends of the separation pipe and the liquid carrying pipe can also implement the sealing mode and the structure with the same technical function.

As shown in fig. 7, which is an enlarged view of a portion A3 in fig. 4, the structure of the liquid inlet sand control pipe is illustrated. To prevent or reduce the entry of solid particles into the carrier pipe 130, the tubing string of the hydrocarbon collection apparatus further includes an inlet sand control pipe 160 connected to the separator pipe 120; the middle hole of the liquid inlet sand control pipe 160 is communicated with the middle hole of the liquid carrying pipe 130, and the pipe wall is provided with a sieve pore 161 which is communicated with the inside and the outside. Like this, when liquid entering takes liquid pipe 130, just need the sieve mesh 161 entering through feed liquor sand control pipe 160, and then realize the filtration to liquid, reduce the adverse effect that the particulate matter carried liquid, improve and take liquid pipe 130 to take liquid ability. In this embodiment, the tubular column of the oil and gas collecting device further comprises a liquid and gas collecting sleeve 163 located outside the liquid inlet sand control pipe 160; the upper end of the liquid-gas collecting sleeve 163 is fixed to the liquid inlet sand control pipe 160 (e.g., by screwing), the lower end is open, and the inner wall surface of the liquid-gas collecting sleeve 163 at least corresponds to a part of the sieve holes 161. Liquid gas collection sleeve 163 can increase partial gas and pass through the entering of sieve mesh 161 along with liquid and carry liquid pipe 130, and after closing the well, can gather more gas and get into carry liquid pipe 130, reduce relatively the liquid column height when opening the well in carrying liquid pipe 130 is convenient for the lower loop and opens the well and carry liquid.

In order to ensure the discharge of solid particles during cleaning operations, the tubing string of the hydrocarbon collection device further includes a sand discharge valve section 170 and a sand discharge valve plug 171. Referring to fig. 8, fig. 8 is an enlarged view of a portion A4 in fig. 4, mainly illustrating the structure of the sand discharge valve section. The sand discharge valve section 170 may be connected to a lower end of the liquid inlet sand prevention pipe 160, and a sand discharge passage 170a is formed therein; a sand discharge limiting bulge 170b is formed at the lower part of the sand discharge channel 170a; the spacing distance between the sand discharge spacing projection 170b and the lower end face of the inner boss of the liquid inlet sand prevention pipe 160 is larger than the height of the sand discharge valve plug 171, so that the sand discharge valve plug 171 can move up and down in the sand discharge channel 170a by a proper distance; the upper end surface of the sand discharge valve plug 171 is in sealing fit with the lower end surface of the inner boss of the liquid inlet sand control pipe 160. The lower end face of the sand discharge valve plug 171 is provided with a liquid passing notch.

Thus, when the liquid collecting and discharging operation is performed, the sand discharge valve plug 171 has different up-and-down pressures, so that the sand discharge valve plug 171 moves upwards, the upper end surface of the sand discharge valve plug 171 is in sealing fit with the lower end surface of the inner boss of the liquid inlet sand control pipe 160, and liquid cannot enter from the lower end surface of the liquid inlet sand control pipe 160 and only enters the liquid inlet sand control pipe 160 through the sieve holes 161; when carrying out clean operation, take pressure gas, raffinate or fixed granule top-down to promote the stifled 171 of sand discharge valve to move down, the up end of the stifled 171 of sand discharge valve with the sealed of terminal surface is relieved under the interior boss of feed liquor sand control pipe 160, because the stifled 171 external diameter of sand discharge valve is less than the internal diameter of sand discharge passageway 170a forms great through-flow space around the stifled 171 of sand discharge valve promptly, passes through there is the liquid breach the lower terminal surface of the stifled 171 of sand discharge valve, can make raffinate or fixed granule discharge, guarantees clean effect.

It can be understood that the outer surface of the sand discharge valve plug 171 can form an outer groove, and the outer groove can be an unclosed ring, so that the sand discharge valve plug can conveniently go upwards smoothly when a well is opened, or go downwards to meet solid particles and is not easy to be stuck when the well is closed.

The first middle channel between the liquid-gas separation cavity Y1 and the communicating cavity Y2, and the second middle channel between the liquid-gas separation cavity Y1 and the liquid carrying cavity Y3 can be realized through proper pipelines, and corresponding pore channels can be arranged to form. In the embodiments shown in fig. 1, 9, 10, the communication is achieved by a combination of the tree 200 and the string 100.

Referring to fig. 9 and 10, fig. 9 illustrates the structure of the above ground portion of the oil and gas collection device, mainly the structure of the collection tree portion; FIG. 10 shows the structure of the combination of the tree and the string.

As shown in fig. 10, the tree 200 includes a lower four-way member 25 and an upper connecting member 21 which are fixedly connected to each other in an upper and lower direction. The lower four-way member 25 forms a lower through hole, an upper through hole, a left through hole and a right through hole; the upper connection member 21 forms an upper hole, a lower hole, and a bypass hole. The upper through hole of the lower four-way member 25 is opposed to the lower hole of the upper connecting member 21.

The lower through hole of the lower four-way member 25 is connected with the outer sleeve 110 of the pipe column 100; the connection head 16 is positioned in the upper through hole of the lower four-way member 25 by a stepped structure and is laterally locked by a fixing pin 24. The lower end of the connecting head 16 is connected with the upper end of the separating tube 120 through the short pipe connector 15 and the pipe coupling 14, and simultaneously, the liquid-gas separation cavity Y1 between the outer sleeve 110 and the separating tube 120 is communicated with the right through hole to form a first bypass hole 221.

The upper hole of the upper connecting piece 21 is inserted into the overflowing connecting head 19 and is positioned in the connecting head 16 through a step, and the lower end of the overflowing connecting head 19 is connected with the upper end of the liquid carrying pipe 130. The upper part of the overflowing connector 19 is sealed with the upper hole of the upper connector 21, and the outer cylindrical surface of the lower step matching part is provided with an overflowing groove which is communicated with a communicating cavity Y2 between the liquid carrying pipe 130 and the separation pipe 120 and communicated with the second bypass hole 231. An overcurrent connector 19 is fixed in the connector 16 by a connector pressing cap 18.

Through the structure, the gas-liquid outlet 211 communicated with the liquid carrying cavity Y3, the first bypass hole 221 communicated with the liquid-gas separation cavity Y1 and the second bypass hole 231 communicated with the communication cavity Y2 can be formed in the central pipe fitting of the collecting tree.

Referring again to fig. 9, in this embodiment, the second bypass hole 231 and the first bypass hole 221 may be communicated through the bypass pipe 230, and a suitable pipe valve may be disposed in the bypass pipe 230 to control the opening and closing of the bypass pipe 230. Wherein, the upper hole of the upper connecting piece 21 is communicated with a collection drain pipe 210 through a small four-way 39 and is communicated with an external pipeline through a collection drain valve 41.

In this embodiment, a throttling device 222 is disposed between the second bypass hole 231 and the first bypass hole 221. Through throttling arrangement 222, can control from the gas-liquid separation chamber Y1 exhaust gas, match the gas liquid volume adaptation better carry liquid pipe 130, realize the best liquid effect of carrying, can control the stratum exploitation simultaneously, fully protect the stratum, the extension exploitation time to realize the best economic benefits of gas well.

The size of the valve port of the throttling device 222 can be adjusted to realize gas-liquid matching, the liquid carrying pipe 130 can be prepared to carry liquid, the operation on the ground is more convenient, or the fixed flow production is controlled to be implemented.

A one-way conduction valve 223 that is one-way conducted from the first bypass hole 221 to the second bypass hole 231 may be provided between the second bypass hole 231 and the first bypass hole 221. Like this, when utilizing external air supply to pass through intercommunication chamber Y2, gas distribution hole 132, gas-liquid mixing chamber 131 to get into and take liquid chamber Y3, can avoid getting into liquid-gas separation chamber Y1 through first by pass hole 221, and then guarantee to take the liquid effect.

It is understood that the one-way conduction valve 223 may be installed vertically or horizontally in a connection pipe between the first bypass hole 221 and the second bypass hole 231.

It can be understood that a first bypass orifice pipe 220 may be arranged between the first bypass orifice 221 and the one-way conductance valve 223, or between the first bypass orifice 221 and the throttling device 222, and a proper pipe valve may be arranged in the first bypass orifice pipe 220 to control the on-off of the pipe; the restriction 222 may also be configured in a multi-pass configuration to provide a backup interface for adding an external source of gas, medication, or a drive device, etc. In this embodiment, in order to ensure that the throttling device 222 works reliably, prevents freezing blockage, and the like, the throttling protection device 31 is further arranged on the outer surface of the shell of the throttling device 222, such as a heating device, a heat preservation device, or other medicament devices, so as to ensure use in alpine regions and improve applicability.

The throttling device 222 can be provided with a driving and controlling module, so that ground operation and management are facilitated, and functions of constant flow production and the like can be controlled and implemented.

In this embodiment, as shown in fig. 10, the first bypass hole 221 and the gas-liquid outlet 211 are connected to an on-off control valve 224. Therefore, when the well is closed, the on-off control valve 224 is opened to enable the first bypass hole 221 and the gas-liquid outlet 211 to be communicated, so that pressurized gas formed by separation of the liquid-gas separation cavity Y1 directly enters the liquid carrying cavity Y3, and further residual liquid or solid particles in the liquid carrying cavity Y3 can be discharged downwards, and the small-diameter liquid carrying pipe 130 is cleaned; the cleaning operation is carried out, and convenience is provided for next circulation well opening and liquid carrying. Of course, an on-off valve may be provided in the first intermediate passage to control the on-off of the first intermediate passage.

When the on-off control valve 224 is connected between the first bypass hole 221 and the gas-liquid outlet 211 for communication, a one-way conduction valve 223 from the first bypass hole 221 to the second bypass hole 231 is arranged between the second bypass hole 231 and the first bypass hole 221; an external gas source can be used to introduce into the liquid-carrying chamber Y3 to clean the residual liquid, the adhered or deposited solid particles.

It can be understood that the on-off control valve and the communication pipeline thereof can be arranged according to the requirement of well conditions, and can also be not arranged.

Based on above-mentioned oil gas collection system, the embodiment of the utility model provides an oil gas collection method includes following step:

1. the well is opened to connect the gas-liquid outlet 211 with the external pipe to discharge the liquid.

2. The gas at the upper part separated by the liquid-gas separation chamber Y1 enters the communication chamber Y2 through the first bypass hole 221 and the second bypass hole 231 under pressure;

3. the gas enters the gas-liquid mixing chamber 131 through the gas distribution holes 132 in the tube wall of the liquid carrying tube 130;

4. in the gas-liquid mixing chamber 131, a predetermined gas-liquid suspension mixture is formed, and flows to the outer pipeline through the liquid carrying pipe 130 and the gas-liquid outlet 211, so that collection is realized.

Similarly, the gas entering the communication cavity Y2 can enter the gas-liquid mixing chamber 131 through the gas distribution holes 132 in the tube wall of the liquid carrying tube 130; the gas-liquid mixture with the optimal gas-liquid ratio is formed in the gas-liquid mixing chamber 131, the matching of the pipe diameters of the liquid carrying pipes is realized, and the liquid carrying capacity of the liquid carrying pipe 130 can be exerted, namely, the liquid collecting and discharging operation is carried out. Through gas distribution hole 132 with take liquid pipe 130 can control the gas-liquid ratio, and then avoid the formation of liquid column slug, and then avoid the adverse effect that liquid column slug produced, realize the utility model discloses a purpose.

Similarly, the throttling device 222 arranged in the collection tree also has the gas distribution or matching function, and can control the implementation of fixed flow production, control the exploitation of the stratum and fully protect the stratum.

By utilizing the oil gas collecting device, the oil gas collecting method also comprises the following steps:

5. shutting in the well, so that the gas-liquid outlet 211 is disconnected with an outer pipeline;

6. the gas separated by the liquid-gas separation chamber Y1 and positioned at the upper part enters the liquid carrying chamber Y3 through the first bypass hole 221 under the action of pressure;

7. the gas reaches the liquid level in the well through the middle hole of the liquid carrying pipe 130, and meanwhile, residual liquid and retained solid particles in the liquid carrying pipe 130 are carried to the bottom of the well, so that the liquid carrying pipe 130 is cleaned.

Thus, the cleaning operation of the liquid carrying pipe 130 can be realized, and meanwhile, preparation is made for next circulation well opening, so that the next circulation well opening and the smooth liquid carrying are ensured. It can be understood that the on-off control valve and the communication pipeline thereof can be arranged according to the requirement of the well condition or not.

It will be appreciated that the above-described method is also not limited to practice with the above-described hydrocarbon collection apparatus.

It should be understood, however, that the present invention is not limited to the particular embodiments described above, but is to be accorded the widest scope consistent with the principles of the present invention. Such modifications and finishes are also to be considered as the scope of protection of the present invention.

Claims (10)

1. An oil gas collecting device comprises a collecting tree and a pipe column, and is characterized in that,

the pipe column comprises an outer sleeve (110), a separation pipe (120) and a liquid carrying pipe (130) which are arranged from outside to inside; a liquid-gas separation cavity (Y1) communicated below the liquid level in the well is formed between the outer sleeve (110) and the separating tube (120), a communication cavity (Y2) is formed between the separating tube (120) and the liquid carrying tube (130), and a liquid carrying cavity (Y3) is formed in the liquid carrying tube (130); the bottom of the communicating cavity (Y2) is closed; the lower opening of the middle hole of the liquid carrying pipe (130) is communicated below the liquid level in the well; at least one gas-liquid mixing chamber (131) is arranged in the liquid carrying cavity (Y3);

the collection tree is provided with a gas-liquid outlet (211), a first bypass hole (221) and a second bypass hole (231), the gas-liquid outlet (211) is communicated with the liquid carrying cavity (Y3), the liquid-gas separation cavity (Y1) is communicated with the first bypass hole (221), and the communication cavity (Y2) is communicated with the second bypass hole (231); the second bypass hole (231) is communicated with the first bypass hole (221), and gas in the liquid-gas separation chamber (Y1) is introduced into the communication chamber (Y2); the gas-liquid mixing chamber (131) is communicated with the communicating cavity (Y2) through a gas distribution hole (132) in the pipe wall of the liquid carrying pipe (130).

2. The hydrocarbon collection device of claim 1, wherein a restriction (222) is provided between the second bypass bore (231) and the first bypass bore (221).

3. The hydrocarbon collection device of claim 1, further comprising a transition section (140) and a transition pipe (141);

the liquid carrying pipe (130) is connected with the lower end of the liquid carrying pipe (140), and a cleaning channel (140 a) is formed in the liquid carrying pipe; a limiting bulge (140 b) is formed at the lower part of the cleaning channel (140 a);

the outer diameter of the liquid passing pipe (141) is smaller than the inner diameter of the cleaning channel (140 a), the upper end face of the liquid passing pipe is in sealing fit with the lower end face of the liquid carrying pipe (130), and a liquid passing hole (140 d) of the liquid passing pipe (141) corresponds to a middle hole of the liquid carrying pipe (130); the liquid passing holes (140 d) form liquid passing holes with fixed proportion;

the limiting distance between the limiting protrusion (140 b) and the lower end face of the liquid carrying pipe (130) is larger than the height of the liquid passing pipe (141).

4. The oil and gas collection device according to claim 3, characterized in that the inner wall of the upper end or/and the inner wall of the lower end of the cleaning channel (140 a) is/are provided with a guide convex rib (140 c), and the guide convex rib (140 c) is in sliding fit with the outer peripheral surface of the liquid passing pipe (141) in the up-down direction.

5. The hydrocarbon collection device of claim 3, further comprising a limit nipple (150); the lower end surface of the liquid passing pipe section (140) is in sealing fit with the upper end surface of the limiting short connecting pipe (150); the limiting short connecting pipe (150) is connected with the lower end of the separating pipe (120), and the middle hole of the limiting short connecting pipe is communicated with the liquid passing hole (140 d) of the liquid passing pipe section (140).

6. The oil and gas collection device as claimed in claim 5, wherein the gas-liquid mixing chamber (131) comprises a conical cavity with a radius gradually increasing from bottom to top, and the center line of the conical cavity is coincident with the center line of the liquid carrying cavity (Y3);

the gas distribution hole (132) comprises a plurality of proportional vent holes, and the openings of the proportional vent holes are uniformly distributed around the center line of the liquid carrying cavity (Y3).

7. The hydrocarbon collection device of claim 6, wherein the proportional vent and/or weep holes (140 d) are formed of a flush resistant alloy.

8. The oil and gas collection device of claim 6, wherein the proportional vent has a constant pressure rupture disc seal.

9. The hydrocarbon collection device of claim 6, further comprising a liquid inlet sand control pipe (160) connected to the separator pipe (120) and a liquid gas collection sleeve (163) located outside the liquid inlet sand control pipe (160); the upper end of the middle hole of the liquid inlet sand control pipe (160) is communicated with the middle hole of the liquid carrying pipe (130), and the pipe wall of the liquid inlet sand control pipe is provided with a sieve hole (161) communicated with the inside and the outside; the upper end of the liquid-gas collecting sleeve (163) is relatively fixed with the liquid inlet sand control pipe (160), the lower end of the liquid-gas collecting sleeve is open, and the inner wall surface of the liquid-gas collecting sleeve (163) at least corresponds to part of the sieve holes (161).

10. The hydrocarbon collection device of claim 9, further comprising a sand drain valve section (170) and a sand drain plug (171);

the sand discharge valve section (170) is connected to the lower end of the liquid inlet sand prevention pipe (160), and a sand discharge channel (170 a) is formed in the sand discharge valve section; a sand discharge limiting bulge (170 b) is formed at the lower part of the sand discharge channel (170 a);

the outer diameter of the sand discharge valve plug (171) is smaller than the inner diameter of the sand discharge channel (170 a), and the upper end surface of the sand discharge valve plug is in sealing fit with an inner boss of the liquid inlet sand control pipe (160);

the sand discharge limiting protrusion (170 b) and the lower end face limiting distance of the liquid inlet sand control pipe (160) are greater than the height of the sand discharge valve plug (171).

Images