CN114452725A

CN114452725A - Gas-liquid separation system

Info

Publication number: CN114452725A
Application number: CN202111671113.0A
Authority: CN
Inventors: 刘乔平; 李浩然; 刘玉真; 李牧; 郭波; 陈筱琳; 彭英
Original assignee: Beijing Renchang Deheng Energy Technology Research Institute Co ltd; China Petroleum and Chemical Corp; Sinopec Chongqing Fuling Shale Gas Exploration and Development Co Ltd
Current assignee: Beijing Renchang Deheng Energy Technology Research Institute Co ltd; China Petroleum and Chemical Corp; Sinopec Chongqing Fuling Shale Gas Exploration and Development Co Ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-05-10

Abstract

The invention relates to the technical field of shale gas exploitation, and particularly discloses a gas-liquid separation system which comprises a treatment tank, and a containing box and a demisting box which are positioned in the treatment tank, wherein an input end and a liquid discharge pipe are arranged on the containing box, the input end of the containing box extends out of the treatment tank, a plurality of separators are fixedly arranged in the containing box, and the plurality of separators are uniformly distributed in the containing box; demisting tank top fixed mounting has the exhaust end, and the exhaust end upwards stretches out the processing jar, and the demisting tank internal fixation has the defroster, all installs the inlet end on every defroster and gives vent to anger the end, and the end of giving vent to anger inserts the demisting tank internal, and the inlet end communicates with the processing jar, and fixed mounting has the blocking net in the demisting tank. The scheme is used for solving the problem that in the existing separation technology, the shale gas with foam is still not thoroughly defoamed after being separated by the gravity separator and the coalescing filter in the gas gathering station, so that fog drops and foam exist in the shale gas.

Description

Gas-liquid separation system

Technical Field

The invention relates to the technical field of shale gas exploitation, in particular to a gas-liquid separation system.

Background

In the shale gas development process, along with the continuous production of gas wells, after foam drainage measures are carried out on part of water-flooded gas wells, the production yield of the gas wells is effectively prolonged, the average daily increase of the yield of a single well is effectively increased, and the measure effect is good. The foam discharging and mining measures have the advantages of quick effect, wide adaptability and high compatibility with other process measures (can be combined with measures such as gas lift, pressurized mining and plunger pistons).

The application of foam discharging and extracting measures usually requires that a certain amount of foaming agent is injected into a hollow part of a wellhead oil sleeve (namely an annular space between an oil pipe and a sleeve, the oil pipe is positioned in the sleeve), and a proper amount of defoaming agent is injected into a wellhead to achieve the purpose of defoaming, the shale gas after defoaming enters a gas collecting station, and the natural gas process flow of the gas collecting station comprises a heating furnace, a separator, a compressor and the like. Shale gas firstly enters a heating furnace for heating, is subjected to gravity separation by a separator and is filtered and separated by a coalescing filter, then is pressurized by a compressor, and enters a dehydration station through a gas collection trunk line for centralized dehydration treatment. In the process, if defoaming is not complete after a defoaming agent is injected into a wellhead, the shale gas with foam enters a compressor, the main component of the defoaming agent is silicone oil, the foam carried by the shale gas is easily attached to the surface of a filter screen of the compressor, and meanwhile, impurities (such as proppant particles for fracturing and stratum clay) are more easily carried in the shale gas due to the existence of the foam, so that the filter screen is easily blocked by the impurities, and further the operation of the compressor is abnormal; on the other hand, foam liquid carrying can cause the accumulation of liquid in a gathering and transportation pipe network, and the normal transportation of shale gas is influenced; in addition, once the shale gas with foam enters a downstream dehydration station, triethylene glycol solution in the dehydration station is inevitably polluted, so that the triethylene glycol solution is foamed, the dehydration effect of the shale gas is greatly reduced, and the normal production of a gas field is further influenced.

In order to solve the problems, the existing shale gas foam solution technology is a mode of a gravity separator and a coalescing filter which are connected in series to remove liquid and foam in shale gas from a wellhead.

Disclosure of Invention

The invention aims to provide a gas-liquid separation system to solve the problem that foam and fog drops contained in shale gas in the prior art cannot be effectively eliminated.

In order to achieve the above object, the basic scheme of the invention is as follows:

the utility model provides a gas-liquid separation system, is equipped with intake pipe, blast pipe and discharge pipe including handling jar and separator on the separator, the blast pipe and the discharge pipe of separator all with the intercommunication of handling jar inner chamber, still including setting up the defroster in handling jar, be equipped with the inlet end on the defroster and give vent to anger the end, give vent to anger the end and be used for the gas after the outside discharge separation.

Compare the beneficial effect in prior art:

when the embodiment is adopted, the shale gas with pressure at the bottom of the well enters the separator for gas-liquid-solid separation from the gas inlet pipe, the liquid and the solid generated after separation are discharged from the discharge pipe, the separated gas is discharged into a treatment tank through an exhaust pipe, after the gas is separated by a separator, large foams in the shale gas are broken, but the shale gas still contains mist liquid or tiny foams or tiny solids, the shale gas with the mist liquid, the micro-foam and the micro-solid enters the demister from the gas inlet end of the demister for gas-liquid-solid separation again, so that the foam amount and solid impurities contained in the shale gas passing through the system are almost completely eliminated, and then the problem that fog drops and foam can not be intercepted and eliminated in the mode of defoaming treatment by using a gravity separator and a coalescing filter in series in the prior art is solved.

In addition, in this scheme, the existence of treatment tank makes the intercommunication between separator and the defroster become simple and convenient on the one hand, and on the other hand, the existence of treatment tank has prolonged the delivery path of shale gas, is favorable to under the delivery path in the shale gas tiny foam and vaporific liquid gather by oneself and fall to in the treatment tank, promotes the elimination effect to foam in the shale gas.

Further, still including holding the case, holding and being equipped with the input on the case, the quantity of separator has a plurality ofly, and the intake pipe of every separator all communicates with holding the incasement chamber.

Has the advantages that: when the scheme is adopted, the shale gas with the foam and with pressure needs to enter the containing box before entering the separator, the shale gas carrying the foam is temporarily stored in the containing box due to the limited volume in the containing box, the foam is gathered in the containing box, and part of the foam can be coalesced to form liquid drops to play a defoaming role;

in addition, when this scheme of adoption, a plurality of separators exist and make the defoaming treatment mode that carries out a small amount of many copies and go on simultaneously to the shale gas of exploiting out, and this kind of mode is favorable to improving defoaming speed and the defoaming effect that foam eliminated in the shale gas.

Further, the containing box is located in the treatment tank, a liquid discharge pipe is arranged on the containing box, and the liquid discharge pipe is communicated with the treatment tank.

Has the advantages that: the scheme enables liquid separated from the containing box to be discharged into the treatment tank for uniform treatment.

Further, a plurality of the separators are evenly distributed in the accommodating box.

Has the advantages that: this scheme makes the gas in the holding box can evenly flow into the solid-liquid-gas separation that realizes taking foam shale gas in each separator.

Furthermore, the separator adopts a centrifugal separator, and a discharge pipe is provided with a groove or a through hole.

Has the advantages that: when the separator defoams the shale gas containing foam, the shale gas continuously enters the centrifugal separator with pressure, solid and foam in the gas impact the inner wall of the separator under the action of centrifugal force, and the gas is discharged from the exhaust pipe in a vortex mode; if no groove or through hole is arranged on the discharge pipe, part of liquid and solid adhered to the discharge pipe can be easily taken away under the vortex action of the airflow and discharged from the exhaust pipe in the continuous separation process of the separator, so that the amount of impurities and liquid in the separated gas is increased; but this scheme is through the setting of recess or through-hole for liquid is after receiving the air current influence, and liquid and solid can move to the recess and increase the degree of difficulty that liquid and solid impurity were taken away or make solid and liquid directly discharge from the through-hole, reduce the liquid and the solid that have already separated and carried the problem once more by the air current.

Furthermore, a conical section is arranged on the discharge pipe, a groove or a through hole is arranged on the conical section of the discharge pipe, and the exhaust pipe is positioned above the discharge pipe.

Has the advantages that: through the setting of toper section, realize the water conservancy diversion to the gas in the separator for gas can move up more fast and then discharge from the blast pipe, and liquid and solid then move down along the discharge pipe under the action of gravity, are favorable to improving the separation effect and the separation efficiency of separator.

Furthermore, still including the defogging case that has the exhaust end, the end and the defogging case inner chamber intercommunication of giving vent to anger of defroster are equipped with the arresting net in the defogging case, and the arresting net is located the end top of giving vent to anger of defroster.

Has the advantages that: this scheme is through the setting of blocking the net in the defogging case to the convenient vaporific liquid, the fine foam and the fine solid that fail to eliminate to the defroster all carry out further elimination.

Further, the defogging box is positioned in the treatment tank, the exhaust end of the defogging box extends out of the treatment tank, and the liquid discharge pipe is arranged at the bottom of the defogging box and positioned in the treatment tank.

Has the advantages that: when this scheme of adoption, the liquid that obtains after separating the liquid in the shale gas in the defogging case flows into the treatment tank along the fluid-discharge tube, and the convenience is unified through the treatment tank to the liquid that obtains of separation and is handled.

Further, the demister adopts a vane type rotational flow demister.

Has the advantages that: vane type whirl defroster makes the shale gas that gets into the defroster get into and flow with the whirl mode along the axis, and at the whirl in-process, tiny foam among the shale gas strikes the defroster inner wall and realizes broken foam, and liquid after the broken foam is stayed on the inner wall, and vaporific liquid strikes the defroster inner wall and attaches on the defroster inner wall, and tiny solid changes the moving direction and can not continue to discharge through the end of giving vent to anger along with gas after striking the defroster inner wall, realizes the separation of gas, liquid and solid.

Further, the defroster adopts the vortex defroster, and the section of giving vent to anger of defroster is the toper, and the cross-sectional area of the end of giving vent to anger diminishes along the air current direction gradually.

Has the advantages that: when this scheme of adoption, the vortex defroster makes shale gas get into with the tangential, and discharge with the vortex form, the direction that this in-process shale gas removed changes, because of gaseous in the gas, the density difference of liquid and small solid, the cross-sectional area because of giving vent to anger the end diminishes along the air current direction gradually at this in-process, make the small foam among the shale gas strike the defroster and give vent to anger the end inner wall and realize breaking the foam, liquid after breaking the foam is stayed on the inner wall, vaporific liquid strikes the defroster inner wall and attaches on the defroster inner wall, small solid changes the moving direction and can not continue to discharge through the end of giving vent to anger along with gas after striking the defroster inner wall, realize gas, the separation of liquid and solid.

Drawings

FIG. 1 is a front sectional view of a storage tank and a defogging tank according to a first embodiment of the present invention, as installed on the left and right sides of a processing tank;

FIG. 2 is a front sectional view of the mist eliminating box and the accommodating box of the first embodiment of the present invention, which are installed in the processing tank in the left and right directions;

FIG. 3 is a front cross-sectional view of the present containment tank and separator of FIG. 1;

FIG. 4 is a top view of a separator according to an embodiment of the present invention with only one inlet pipe;

FIG. 5 is a top view of a separator with three inlet tubes according to an embodiment of the invention;

FIG. 6 is a front cross-sectional view of a separator according to one embodiment of the invention;

FIG. 7 is a front cross-sectional view of a mist eliminator in accordance with a second embodiment of the present invention.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the device comprises a containing box 1, an input end 11, a liquid discharge pipe 12, a separator 2, an air inlet pipe 21, an exhaust pipe 22, a discharge pipe 23, a demisting box 3, an exhaust end 31, a demister 4, an air inlet end 41, an air outlet end 42, a blocking net 5 and a treatment tank 10.

Example one

First embodiment referring to fig. 1 to 6, a gas-liquid separation system comprises a treatment tank 10 and a containing box 1 and a defogging box 3 fixedly installed in the treatment tank 10, wherein the containing box 1 and the defogging box 3 can be arranged in the treatment tank 10 from left to right, or from top to bottom, or even the connecting line of the containing box 1 and the defogging box 3 in the treatment tank 10 is oblique, and in short, the arrangement of the containing box 1 and the defogging box 3 in the treatment tank 10 can be changed according to the specific needs of a construction site.

Hold and install input 11 and fluid-discharge tube 12 on the case 1, input 11 can set up at the top or the lateral part that hold case 1, and fluid-discharge tube 12 is connected in the bottom that holds case 1, and the input 11 that holds case 1 stretches out treatment tank 10, holds 1 interior fixed mounting of case and has a plurality of separators 2, and a plurality of separators 2 evenly distributed is in holding case 1.

Each separator 2 adopts a centrifugal separator 2, an air inlet pipe 21, an air outlet pipe 22 and an exhaust pipe 23 are arranged on each separator 2, the air inlet pipe 21 is communicated with the inner cavity of the containing box 1, the exhaust pipe 23 is arranged at the bottom of each separator 2, the exhaust pipe 23 and the exhaust pipe 22 extend out of the containing box 1, the air inlet pipe 21 facilitates shale gas to enter the separator 2 tangentially, the exhaust pipe 22 and the exhaust pipe 23 are coaxially arranged, the exhaust pipe 22 is positioned at the upper end of the separator 2, and the exhaust pipe 23 is positioned at the lower end of the separator 2; wherein the number of the air inlet pipes 21 can be one or more, and the plurality of air inlet pipes 21 can facilitate the separator 2 to realize gas-liquid separation more quickly.

The discharge pipe 23 is integrally formed with a tapered section, and the tapered section of the discharge pipe 23 is provided with a groove or a through hole, wherein the groove or the through hole is linear or curved in order to achieve better effect and facilitate processing.

An exhaust end 31 is fixedly installed at the top of the demisting tank 3, the exhaust end 31 extends upwards out of the treatment tank 10, the exhaust end 31 of the embodiment is used for being communicated with the input end 11 of the gas collecting station, and a liquid discharge pipe 12 is also installed at the bottom of the demisting tank 3 as well as the accommodating tank 1.

The demister 4 is fixedly connected to the demisting box 3, the number of the demisting devices 4 can be multiple, the plurality of demisting devices 4 are uniformly distributed on the demisting box 3, each demister 4 can adopt a vane type cyclone demister 4, each demister 4 is provided with an air inlet end 41 and an air outlet end 42, the air outlet end 42 and the air inlet end 41 of the vane type cyclone demister 4 are positioned on the same axis, the air outlet end 42 is inserted into the demisting box 3, the air inlet end 41 is communicated with the treatment tank 10, the vane type cyclone demister 4 enables the shale gas with mist liquid, micro foam and micro solid to enter from the air inlet end 41 at the bottom and be discharged to the air outlet end 42 in a cyclone mode, the flow direction of the shale gas changes in the process, the micro foam in the shale gas impacts the inner wall of the demister 4 to break the foam, the liquid after the foam is remained on the inner wall, the mist liquid impacts the inner wall of the demister 4 and is attached to the inner wall of the demisting device, the micro solid changes the moving direction after impacting the inner wall of the demister 4 and cannot be continuously discharged through the gas outlet end 42 along with the gas, so that the separation of the gas, the liquid and the solid is realized; the air outlet end 42 of the demister 4 extends into the demisting tank 3 and is communicated with the inner cavity of the demisting tank 3.

A blocking net 5 is fixedly arranged in the demisting box 3, and the blocking net 5 is positioned above the air outlet end 42 of the demister 4.

When the system is used, the treatment tank 10 is fixedly connected to the ground or an installation platform on a construction site.

The specific implementation process is as follows:

when the embodiment is adopted, the shale gas with pressure at the bottom of the well enters the containing box 1 through the input end 11, because the volume of the containing box 1 is limited, the shale gas with foam is temporarily stored in the containing box 1, the foam is gathered in the containing box 1, and part of the foam is coalesced to form liquid drops so as to achieve the defoaming effect (the liquid formed after defoaming is discharged from the liquid discharge pipe 12); then, the shale gas with foam uniformly enters the air inlet pipes 21 of the separators 2 under self-pressure, because the air inlet pipes 21 tangentially supply air, and the separators 2 are centrifugal separators 2, liquid (foam) and solid impurities in the shale gas with foam are thrown to the inner side walls of the separators 2 under the action of centrifugal force, the foam is broken after colliding with the inner side walls of the separators 2, and the purpose of defoaming is achieved, and the defoamed gas is discharged from the exhaust pipe 22; in addition, the liquid formed after the foam is eliminated is also attached to the inner wall of the separator 2 and moves to the discharge pipe 23 along the inner wall of the separator 2, and the solid impurities are discharged to the discharge pipe 23 under the self gravity, namely the separation of gas, liquid and solid is realized through the separator 2. The preliminary elimination of foam in the shale gas is realized to this in-process containing box 1, then utilizes a plurality of separators 2 to carry out defoaming processing a small amount of many copies to the shale gas of taking the foam that gets into containing box 1 simultaneously for the shale gas processing speed to carrying the foam is fast and treatment effect is good, realizes the elimination in a large number of foam in the shale gas and the elimination of solid (the shale gas after separator 2 separation still contains vaporific liquid or tiny foam or tiny solid).

Then, the shale gas with the mist liquid, the micro foam and the micro solid automatically enters the demister 4 from the treatment tank 10 along the gas inlet end 41 of the demister 4 for secondary gas-liquid-solid separation in the continuous shale gas exploitation, and finally, before the gas is discharged, the shale gas is broken by the blocking net 5 and then discharged from the gas outlet end 31 of the demisting box 3. The foam amount and solid impurities contained in the shale gas passing through the system are almost completely eliminated, and the problem that fog drops and foams contained in the shale gas in the prior art cannot be intercepted and eliminated is further solved.

According to the whole arrangement of the embodiment, the shale gas firstly enters the accommodating box 1, then enters the plurality of separators 2, then enters the treatment tank 10, then passes through the demister 4, and finally passes through the blocking net 5 to be discharged from the exhaust end 31 of the demister box 3, the arrangement of the whole system prolongs the flow path of the gas, and the foam is automatically gathered and further gathered into liquid drops in the accumulation process by utilizing the extension of the flow path so as to achieve the purpose of automatically breaking the foam; on the other hand, the gas passes through the separator 2, the demister 4 and the arresting net 5 in sequence on the extended path to realize three-time active foam breaking on the foam shale gas, so that the foam in the gas is completely eliminated, the problem of low defoaming efficiency in the prior art is solved, and the problems of abnormal operation of a compressor, influence on a dewatering station and the like in a subsequent gas gathering station can be thoroughly solved.

In addition, in this embodiment, the existence of the treatment tank 10, on one hand, makes the communication between the separator 2 and the demister 4 simple and convenient, and on the other hand, the existence of the treatment tank 10 prolongs the conveying path of the shale gas, which is beneficial for the micro-bubbles and the mist-like liquid in the shale gas to automatically gather and fall into the treatment tank 10 under the conveying path, and promotes the effect of eliminating the bubbles in the shale gas.

In addition, in the embodiment, the liquid separated by the containing box 1, the solid and the liquid separated by the separator 2 and the liquid separated by the demister 4 are all discharged into the treatment tank 10, so that the liquid and the solid generated by the defoaming treatment can be conveniently and uniformly collected and treated.

Example two

Referring to fig. 7, the difference between the third embodiment and the second embodiment is that in the present embodiment, a vortex demister 4 is used as the demister 4, the air outlet section of the demister 4 is tapered, and the cross-sectional area of the air outlet end 42 is gradually reduced along the air flow direction.

When the embodiment is adopted, the vortex demister 4 enables shale gas to enter in a tangential direction and be discharged in a vortex form, the moving direction of the shale gas in the process is changed, the gas in the gas and the liquid and the small solid are different in density, the cross section area of the gas outlet end 42 is gradually reduced along the gas flow direction in the process, the small foam in the shale gas collides with the inner wall of the gas outlet end 42 of the demister 4 to break foam, the broken liquid is remained on the inner wall of the demister 4, the vaporific liquid collides with the inner wall of the demister 4 and is attached to the inner wall of the demister, the small solid changes the moving direction after colliding with the inner wall of the demister 4 and cannot be discharged along with the gas through the gas outlet end 42, and the separation of the gas, the liquid and the solid is realized.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be defined by the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. The utility model provides a gas-liquid separation system, includes treatment tank and separator, is equipped with intake pipe, blast pipe and discharge pipe on the separator, its characterized in that: the exhaust pipe and the discharge pipe of separator all communicate with the treatment tank inner chamber, still including setting up the defroster in the treatment tank, are equipped with the inlet end on the defroster and give vent to anger the end, give vent to anger the end and be used for the gas after the outside discharge separation.

2. The gas-liquid separation system according to claim 1, characterized in that: still including holding the case, hold and be equipped with the input on the case, the quantity of separator has a plurality ofly, and the intake pipe of every separator all communicates with holding the incasement chamber.

3. The gas-liquid separation system according to claim 2, characterized in that: the containing box is positioned in the treatment tank, a liquid discharge pipe is arranged on the containing box, and the liquid discharge pipe is communicated with the treatment tank.

4. The gas-liquid separation system according to claim 2, characterized in that: a plurality of the separators are evenly distributed in the containing box.

5. The gas-liquid separation system according to claim 1, characterized in that: the separator adopts a centrifugal separator, and a discharge pipe is provided with a groove or a through hole.

6. The gas-liquid separation system according to claim 5, characterized in that: the exhaust pipe is provided with a conical section, the groove or the through hole is arranged on the conical section of the exhaust pipe, and the exhaust pipe is positioned above the exhaust pipe.

7. The gas-liquid separation system according to claim 1, characterized in that: the demisting box is characterized by further comprising a demisting box with an exhaust end, the air outlet end of the demister is communicated with the inner cavity of the demisting box, a blocking net is arranged in the demisting box, and the blocking net is located above the air outlet end of the demister.

8. The gas-liquid separation system according to claim 7, wherein: the defogging box is positioned in the treatment tank, the exhaust end of the defogging box extends out of the treatment tank, and the liquid discharge pipe is arranged at the bottom of the defogging box and positioned in the treatment tank.

9. The gas-liquid separation system according to claim 1, characterized in that: the demister adopts a vane type rotational flow demister.

10. The gas-liquid separation system according to claim 1, characterized in that: the demister adopts a vortex demister, the air outlet section of the demister is conical, and the cross-sectional area of the air outlet end is gradually reduced along the air flow direction.