CN114961673B - Expansion method for salt cavern gas storage - Google Patents
Expansion method for salt cavern gas storage Download PDFInfo
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- CN114961673B CN114961673B CN202110208377.6A CN202110208377A CN114961673B CN 114961673 B CN114961673 B CN 114961673B CN 202110208377 A CN202110208377 A CN 202110208377A CN 114961673 B CN114961673 B CN 114961673B
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- 150000003839 salts Chemical class 0.000 title claims abstract description 82
- 238000000034 method Methods 0.000 title claims abstract description 45
- 239000012267 brine Substances 0.000 claims abstract description 183
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 claims abstract description 183
- 239000007789 gas Substances 0.000 claims abstract description 88
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 50
- 238000007599 discharging Methods 0.000 claims abstract description 34
- 239000003345 natural gas Substances 0.000 claims abstract description 25
- 238000005553 drilling Methods 0.000 claims abstract description 23
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 32
- 239000007924 injection Substances 0.000 claims description 28
- 238000002347 injection Methods 0.000 claims description 28
- 239000004576 sand Substances 0.000 claims description 11
- 238000007789 sealing Methods 0.000 claims description 3
- 239000002352 surface water Substances 0.000 claims description 2
- 239000011797 cavity material Substances 0.000 description 119
- 235000002639 sodium chloride Nutrition 0.000 description 72
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- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 1
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
- E21B43/166—Injecting a gaseous medium; Injecting a gaseous medium and a liquid medium
- E21B43/168—Injecting a gaseous medium
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/28—Dissolving minerals other than hydrocarbons, e.g. by an alkaline or acid leaching agent
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/16—Modification of mine passages or chambers for storage purposes, especially for liquids or gases
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- Geochemistry & Mineralogy (AREA)
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- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
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Abstract
The application discloses a method for expanding a salt cavern gas storage, and belongs to the technical field of salt cavern gas storage. The method comprises the following steps: drilling a directional well at a target position according to the position of a first well of a salt cavern gas storage, wherein the directional well is drilled to the bottom of a cavity of the first well; installing a first brine discharge pipe column in the directional well, wherein one end of the first brine discharge pipe column is positioned in the bottom of a cavity of the first well; and injecting natural gas into the first well, and discharging brine at the bottom of the cavity of the first well to the ground through the first brine discharge pipe column. The purpose of expanding the salt cavern gas storage is achieved.
Description
Technical Field
The application relates to the technical field of salt cavern gas storage, in particular to a method for expanding the capacity of a salt cavern gas storage.
Background
Salt cavern gas reservoirs are one of the major types of underground gas reservoirs, widely distributed throughout the world in various countries and regions. The method for constructing the salt cavern gas storage mainly comprises the steps of drilling a vertical well, and creating a cavity at the bottom of the vertical well by utilizing a water-soluble method so as to form the salt cavern gas storage.
At present, the domestic salt cavern gas storage has the conditions of layered rock salt deposited by land phase, more interlayers and high insoluble matter content, and the cavity making stage needs 3-5 years from the beginning to the end, and a large amount of insoluble matter mixed salt crystals are deposited at the bottom of the cavity to form a pit, and the pit is filled with salt collecting residues. The salt mining residue contains insoluble substances (salt layer stone), soluble salts which are not dissolved (fall to a pit in the initial salt mining process, and are not dissolved any more due to the saturated salt concentration), and brine (mainly exists in the pores of the pit salt mining residue). The pit occupies more than 30% of the whole cavity volume, in addition, the gas injection and the brine discharge are limited by the pipe column condition after the cavity is manufactured, brine at the bottom of the cavity cannot be discharged cleanly, brine with a depth of 5-10 meters remains at the bottom of the cavity, and great waste of the cavity volume is caused. Therefore, there is a need for a method for expanding the salt cavern gas storage, which discharges brine at the bottom of the cavity to the ground, increases the volume of the cavity, and achieves the purpose of expanding the salt cavern gas storage.
Disclosure of Invention
The embodiment of the application provides a method for expanding the salt cavern gas storage, which can achieve the purpose of expanding the salt cavern gas storage. The technical scheme is as follows:
in one aspect, a method for expanding a salt cavern gas storage is provided, the method comprising:
drilling a directional well at a target position according to the position of a first well of a salt cavern gas storage, wherein the directional well is drilled to the bottom of a cavity of the first well;
installing a first brine discharge pipe column in the directional well, wherein one end of the first brine discharge pipe column is positioned in the bottom of a cavity of the first well;
and injecting natural gas into the first well, and discharging brine at the bottom of the cavity of the first well to the ground through the first brine discharge pipe column.
In one possible implementation, the drilling of the directional well at the target location according to the location of the first well of the salt cavern gas storage includes:
determining the target position of the directional well to be drilled according to the positions of a plurality of existing wells in the salt cavern gas storage, wherein the plurality of wells comprise the first well;
drilling a said directional well at said target location.
In one possible implementation, after the injecting natural gas into the first well and discharging brine at the bottom of the cavity of the first well to the surface through the first brine discharge pipe column, the method further includes:
plugging a deflecting section of the directional well;
laterally drilling a first branch directional well above a first deflecting point of the directional well, wherein the first branch directional well is drilled to the bottom of a cavity of a second well, and the second well is a well except the first well in the multiple wells in the salt cavern gas storage;
installing a second brine discharge pipe column in the first branch directional well, wherein one end of the second brine discharge pipe column is positioned in the bottom of a cavity of the second well;
and injecting the natural gas into the second well, and discharging brine at the bottom of the cavity of the second well to the ground through the second brine discharge pipe column.
In one possible implementation, after the injecting the natural gas into the second well and discharging brine at the bottom of the cavity of the second well to the surface through the second brine discharge string, the method further includes:
plugging a deflecting section of the first branch directional well, laterally drilling a second branch directional well above a second deflecting point of the first branch directional well, wherein the second branch directional well is drilled to the bottom of a cavity of a third well, the third well is a well except the first well and the second well in the multiple wells, and the second deflecting point is positioned above the first deflecting point;
installing a third brine discharge pipe column in the second branch directional well, wherein one end of the third brine discharge pipe column is positioned in the bottom of a cavity of the third well;
and injecting the natural gas into the third well, and discharging brine at the bottom of the cavity of the third well to the ground through the third brine discharge pipe column.
In one possible implementation, before the injecting natural gas into the first well, the method further includes:
injecting water into the bottom of the cavity of the first well to dissolve salt in the pit at the bottom of the cavity.
In one possible implementation, the injecting water into the bottom of the cavity of the first well includes any one of:
injecting the water into the bottom of the cavity of the first well through the first brine discharge pipe column;
and injecting the water into the bottom of the cavity of the first well through the wellhead of the first well.
In one possible implementation, the first brine string is fitted with a packer for sealing off an annular space of the first brine string and casing of the directional well.
In one possible implementation, after the installing the first brine string and the first packer in the directional well, the method further comprises:
and installing a wellhead device at the wellhead of the directional well, wherein the wellhead device is connected with a brine discharge pipeline on the ground, and the brine discharge pipeline is connected with the first brine discharge pipe column.
In one possible implementation, the wellhead is also connected to a surface water injection line that connects to the first brine discharge string.
In one possible implementation, one end of the first brine discharge pipe column of the directional well, which is positioned at the bottom of the cavity of the first well, is provided with a sand control device, and the sand control device is used for preventing residues in a pit at the bottom of the cavity of the first well from entering the first brine discharge pipe column.
The beneficial effects that technical scheme that this application embodiment provided include at least:
by drilling a new well near the existing well of the salt cavern gas storage, the new well is a directional well, so that the new well can be drilled to the bottom of the cavity of the existing well, and then a brine discharge pipe column is arranged in the new well, so that one end of the brine discharge pipe column reaches the bottom of the cavity of the existing well, when natural gas is injected into the existing well, brine at the bottom of the cavity of the existing well can be driven to enter the brine discharge pipe column until the brine is discharged to the ground, so that the space originally occupied by the brine at the bottom of the cavity is emptied, the volume of the cavity is increased, the capacity of the salt cavern gas storage is increased, and the purpose of expanding the capacity of the salt cavern gas storage is achieved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of a method for expanding a salt cavern gas storage according to an embodiment of the present application;
FIG. 2 is a flow chart of a method for expanding a salt cavern gas storage according to an embodiment of the present application;
FIG. 3 is a schematic diagram of the relative positions of four gas storage wells and a brine discharge well of a salt cavern gas storage according to an embodiment of the present disclosure;
fig. 4 is a schematic diagram of a cavity before expansion of a salt cavern gas storage according to an embodiment of the present application;
FIG. 5 is a schematic diagram of a process of expanding a gas storage well of a salt cavern gas storage according to an embodiment of the present disclosure;
FIG. 6 is a schematic diagram of a second gas storage well expansion process of a salt cavern gas storage according to an embodiment of the present disclosure;
fig. 7 is a schematic diagram of a salt cavern gas storage after expansion of two gas storage wells is completed.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.
Before the embodiments of the present application are described in further detail, it is to be understood that the terms "bottom," "one end," "another end," "upper," "lower," "side," "inner," and the like referred to herein are used for clarity or simplicity of description only and are not meant to be the only embodiments, nor are they intended to limit the scope of the present application.
The terms "first," "second," "third," "fourth," and the like in this application are used for descriptive purposes only and are not to be construed as indicating or implying any relative importance or number of features indicated, nor are there logical or chronological dependencies between "first," "second," "third," "fourth," or the like, nor are they intended to limit the number and order of execution.
Fig. 1 is a flowchart of a method for expanding a salt cavern gas storage according to an embodiment of the present application. Referring to fig. 1, the method includes:
101. and drilling a directional well at the target position according to the position of the first well of the salt cavern gas storage, wherein the directional well is drilled to the bottom of the cavity of the first well.
The first well can be an existing well of a salt cavern gas storage, such as a vertical well drilled during the construction of the storage.
The distance between the target location and the location of the first well is less than the distance threshold, i.e., the target location is in the vicinity of the first well.
102. After the directional well is well cemented, a first brine discharge pipe column is installed in the directional well, and one end of the first brine discharge pipe column is located in the bottom of the cavity of the first well.
103. And injecting natural gas into the first well, and discharging brine at the bottom of the cavity of the first well to the ground through the first brine discharge pipe column.
The brine can be residual brine at the bottom of the cavity after cavity formation is finished, namely, the brine which cannot be discharged originally at the bottom of the cavity.
According to the method provided by the embodiment of the application, the new well is drilled near the existing well of the salt cavern gas storage, the new well is the directional well, so that the new well can be drilled to the bottom of the cavity of the existing well, then the brine discharging pipe column is arranged in the cavity of the existing well, one end of the brine discharging pipe column is enabled to reach the bottom of the cavity of the existing well, when natural gas is injected into the existing well, brine at the bottom of the cavity of the existing well can be driven to enter the brine discharging pipe column until the brine is discharged to the ground, and therefore the space occupied by the brine originally at the bottom of the cavity is left, the volume of the cavity is increased, the capacity of the salt cavern gas storage is increased, and the purpose of expanding the salt cavern gas storage is achieved.
The flow shown in fig. 1 is a basic flow of the embodiment of the disclosure, and a detailed flow of the technical solution of the disclosure is described below based on the basic flow.
Fig. 2 is a flowchart of a method for expanding a salt cavern gas storage according to an embodiment of the present application. Referring to fig. 2, the method includes:
201. and determining the target position of the directional well to be drilled according to the positions of the plurality of wells in the salt cavern gas storage.
The multiple wells can be gas injection wells or gas storage wells of the existing salt cavern gas storage, such as multiple vertical wells drilled during the construction of the gas storage. In one example, the plurality of wells may include a first well, a second well, a third well, and a fourth well. It will be appreciated that the number of wells is not limited to four, and may be more or less, depending on the specifics of the well spacing, well depth, location coordinates, etc.
In one possible implementation, the distance between the target location of the directional well to be drilled and the locations of the multiple wells is less than a distance threshold, i.e., the target location is in the vicinity of the multiple wells. The directional well can be called as a brine discharging well and is used for discharging brine in the gas storage well to realize expansion. By drilling directional wells near multiple wells, multi-well expansion is facilitated. Referring to fig. 3, fig. 3 is a schematic diagram of the relative positions of four gas injection wells (gas injection well 01, gas injection well 02, gas injection well 03, gas injection well 04) and a brine discharge well (directional well) in a salt cavern gas storage according to the embodiment of the present application, and as shown in fig. 3, four or more adjacent gas injection wells may be selected to determine the position of the brine discharge well.
In some embodiments, this step 201 may be performed by a smart device, such as the smart device receiving the entered location coordinates of the plurality of wells, invoking a target algorithm, and outputting the target location. In addition to the location coordinates of the multiple wells, other parameters may be entered such as vertical well depth, drilling depth, bit size, casing depth, kick-off depth, etc.
202. And drilling a directional well at the target position, wherein the directional well is drilled to the bottom of the cavity of a first well in the plurality of wells.
The first well may be any well of a plurality of wells, or may be a well meeting a certain condition with the target position, such as a well closest to the target position or a well farthest from the target position.
Fresh water can be injected into the first well in the cavity making process of the salt cavern gas storage so as to erode the first well, thereby forming a cavity of the first well. In addition, a large amount of insoluble mixed salt crystals are deposited at the bottom of the cavity of the first well during cavity creation to form a pit. Referring to fig. 4, fig. 4 is a schematic cavity diagram before expansion of a salt cavern gas storage, and fig. 4 shows a gas storage well with a finished cavity and gas injection, where the gas storage well includes a surface casing, a production casing and a production pipe column, the production casing is disposed in the surface casing, the production pipe column is disposed in the production casing, the production pipe column is provided with a safety valve, and a packer is disposed between the production casing and the production pipe column. As shown in fig. 4, a large amount of brine is filled at the bottom of the cavity of the gas storage well, for example, brine is filled above a pit at the bottom of the cavity, brine and solid salt are also present in pit residues, and natural gas is filled above the brine (injected after the cavity is formed by drilling).
A new well is drilled nearby the first well through drilling equipment, the new well is a directional well, and the directional well refers to a well with a certain included angle between the axis of a well cavity and the horizontal plane of a wellhead. Referring to fig. 5, fig. 5 is a schematic diagram of a process of expanding a gas storage well of a salt cavern gas storage according to an embodiment of the present application, and as shown in fig. 5, a directional well is drilled to the bottom of a cavity of a first well (gas injection well 01) and is communicated with a pit at the bottom of the cavity of the first well.
In some embodiments, this step 202 may be performed by a smart device, e.g., the smart device may control the drilling device to drill directional wells at the target location.
It should be noted that, steps 201 to 202 are one possible implementation of drilling a directional well at a target location according to the location of the first well of the salt cavern gas storage. In some embodiments, if expansion is performed only for a single well, a nearby one of the target locations may be determined to drill the directional well based only on the location of the single well.
203. A first brine discharge pipe column is installed in the directional well, and one end of the first brine discharge pipe column is located in the bottom of the cavity of the first well.
In the embodiment of the application, after the directional well is well-fixed (cement is injected into the annular space outside the casing after the casing is put into the well hole), a halogen-discharging pipe column can be put into the directional well, and the halogen-discharging pipe column is called a first halogen-discharging pipe column. As shown in fig. 5, one end of the first brine-discharging pipe column is located at the bottom of the cavity of the first well, and the directional well can be drilled to the bottom of the cavity of the first well and communicated with the pit at the bottom of the cavity of the first well, so that the first brine-discharging pipe column can be lowered into the pit at the bottom of the cavity of the first well.
In one possible implementation, a packer is installed on a first brine string in the directional well, the packer is used for sealing an annular space between the first brine string and a casing of the directional well, and annular space above the packer can be filled with an annular protection liquid to protect the inner wall of the casing from corrosion caused by brine. As shown in fig. 5, the location of the packer may be selected in a deviated section of the directional well (deviated section).
In one possible implementation, the end of the first brine discharge pipe column of the directional well, which is positioned at the bottom of the cavity of the first well, is provided with a sand control device, as shown in fig. 5, which is used for preventing residues in the pit at the bottom of the cavity of the first well from entering the first brine discharge pipe column, so as to avoid blocking the brine discharge pipe column. Wherein the sand control device may be a screen.
In one possible implementation, after installing the first brine string and the first packer in the directional well, the method further comprises: and installing a wellhead device at the wellhead of the directional well, wherein the wellhead device is connected with a brine discharge pipeline and a water injection pipeline on the ground, and the brine discharge pipeline and the water injection pipeline are connected with a first brine discharge pipe column. In this way, on one hand, brine entering the brine discharge pipe column of the directional well from the bottom of the cavity of the first well can be discharged through the ground brine discharge pipe line, and on the other hand, fresh water can be injected into the brine discharge pipe column in the directional well through the ground water injection pipe line so as to enter the bottom of the cavity of the first well and erode the residual salt in the pit. One end of a first brine discharge pipe column arranged in the directional well is positioned in a pit at the bottom of a cavity of the first well, and the other end of the first brine discharge pipe column is positioned at a wellhead and is connected with a brine discharge pipeline and a water injection pipeline on the ground.
In some embodiments, this step 203 may be performed by a smart device, e.g., the smart device may control the installation tool to install the first brine string and the first packer within the directional well.
204. Water is injected into the bottom of the cavity of the first well through the first brine discharge pipe column, and salt in the pit at the bottom of the cavity of the first well is dissolved.
Because one end of the first brine discharge pipe column is positioned in the pit at the bottom of the cavity of the first well, when water (such as fresh water) is injected into the first brine discharge pipe column from the other end of the first brine discharge pipe column, the water flows into the pit at the bottom of the cavity of the first well, so that soluble salt in the pit is dissolved in the water to form brine. The water injected into the bottom of the cavity of the first well can dissolve salt in the pit, and can also dissolve the salt attached to the wall of the cavity flowing through the water to form brine.
The water injection equipment on the ground can inject water into the first brine-discharging pipe column through the water injection pipe line to finally flow into the bottom of the cavity of the first well.
Step 204 is one possible implementation of injecting water into the bottom of the cavity of the first well, and in another possible implementation, injecting water into the bottom of the cavity of the first well includes: water is injected into the bottom of the cavity of the first well through the wellhead of the first well. In this way, the injected water can dissolve the adhering salt on the walls of the flowing cavity, forming brine.
In some embodiments, this step 204 may be performed by a smart device, e.g., the smart device may control the water injection device to inject water through the first brine discharge string to the bottom of the cavity of the first well.
205. And injecting natural gas into the first well, and discharging brine at the bottom of the cavity of the first well to the ground through a first brine discharge pipe column of the directional well.
High-pressure natural gas is injected into the first well from the wellhead of the first well through gas injection equipment, wherein the high pressure is that the pressure is greater than a pressure threshold value, and the injected natural gas can drive brine at the bottom of a cavity of the first well to enter a first brine discharge pipe column of the directional well until the brine is discharged to the ground.
For the case where the first brine discharge pipe is connected to a brine discharge line of the ground, in one possible implementation, discharging brine from the bottom of the cavity of the first well to the ground through the first brine discharge pipe of the directional well comprises: and discharging brine at the bottom of the cavity of the first well to the ground through a first brine discharge pipe column and a brine discharge pipeline of the directional well. Brine driven by natural gas enters the first brine discharge pipe column from one end of the first brine discharge pipe column, which is positioned at the bottom of the cavity of the first well, enters the brine discharge pipeline on the ground from the other end of the first brine discharge pipe column, and is discharged to the ground.
In some embodiments, this step 205 may be performed by a smart device, e.g., the smart device may control the gas injection device to inject natural gas into the first well.
It should be noted that step 204 is an optional step. After the soluble salt in the salt cavern pit is dissolved by water injection, the brine in the pit is discharged by gas injection, and the brine discharged in the case can comprise the brine formed by executing the step 204 and the brine which cannot be discharged originally in the pit, so that the purposes of increasing the cavity volume and increasing the storage capacity of the salt cavern gas storage are achieved.
In some embodiments, step 205 may be directly performed after step 203 is performed, where the discharged brine is the brine that cannot be discharged from the bottom of the cavity, and the purpose of capacity expansion is achieved.
In some embodiments, steps 204 and 205 may also be performed multiple times to increase the expansion effect.
Compared with fig. 4, it can be seen from fig. 5 that brine filled above the pit of the salt cavern gas storage well is discharged, the pit is divided into two parts, the upper part insoluble matter pore contains natural gas, and the lower part insoluble matter pore contains undischarged brine.
206. Plugging the deflecting section of the directional well.
And after the discharging condition of the brine at the bottom of the cavity of the first well reaches the target condition, plugging the deflecting section of the directional well through a plugging tool, if plugging the deflecting section below a certain part, as shown by a black plugging part in fig. 5, completing the expansion of the first well. The target condition is used for measuring whether the brine is discharged or not, and whether the brine discharge condition reaches the target condition or not can be determined according to the estimated brine volume of the cavity volume obtained by earlier measurement and/or according to the accumulated and increased natural gas injection amount.
207. And laterally drilling a first branch directional well above the first deflecting point of the directional well, wherein the first branch directional well is drilled to the bottom of the cavity of the second well.
Wherein the first kick-off point is a starting point of a kick-off section designated to the well. The second well is a well except the first well in the existing multiple wells of the salt cavern gas storage. In the embodiments herein, a branch directional well laterally drilled above a first slant point is referred to as a first branch directional well.
In this step, a first branch directional well is sidetrack drilled above a first kick-off point through a drilling apparatus to the bottom of the cavity of a second well in communication with a pit in the bottom of the cavity of the second well.
Referring to fig. 6, fig. 6 is a schematic diagram of a capacity expansion process of a second gas storage well of a salt cavern gas storage according to an embodiment of the present application, as shown in fig. 6, a branch directional well using a second deflecting point as a starting point of a deflecting section is a first branch directional well, and the second deflecting point is located above the first deflecting point.
In some embodiments, this step 206 and step 207 may be performed by a smart device, e.g., the smart device may control the plugging tool to plug a deviated section of the directional well and then control the drilling device to sidetrack the first branch directional well above the first deviated point.
208. And installing a second brine discharge pipe column in the first branch directional well, wherein one end of the second brine discharge pipe column is positioned in the bottom of the cavity of the second well.
In the embodiment of the application, the brine discharge pipe column installed in the first branch directional well is called a second brine discharge pipe column.
After the first branch directional well is well-fixed, a second brine discharge pipe column can be put into the first branch directional well, as shown in fig. 6, one end of the second brine discharge pipe column is positioned at the bottom of the cavity of the second well (gas injection well 02), and the first branch directional well can be drilled into a pit at the bottom of the cavity of the second well, so that the second brine discharge pipe column can be put into the pit at the bottom of the cavity of the second well.
In one possible implementation manner, the second brine discharge pipe column in the first branch directional well is provided with a packer, which is the same as the packer installed by the first brine discharge pipe column in step 203, and will not be described in detail.
In one possible implementation, the end of the second brine discharge string of the directional well at the bottom of the cavity of the second well is provided with a sand control device. The sand control device is the same as the sand control device set in the first brine discharge pipe in step 203, and will not be described in detail.
209. And injecting water into the bottom of the cavity of the second well through the second brine discharge pipe column to dissolve salt in the pit at the bottom of the cavity of the second well.
210. And injecting natural gas into the second well, and discharging brine at the bottom of the cavity of the second well to the ground through a second brine discharge pipe column.
Step 209 to step 210 are the same as step 204 to step 205, and the same parts will not be described again.
After the brine at the bottom of the first well is discharged, plugging and sidetracking operations are carried out, and then the brine at the bottom of the second well is discharged to the ground through a brine discharge pipe column by using the same method as the first well, including water injection and gas injection, so that the purpose of multi-well capacity expansion can be achieved.
211. Plugging the deflecting section of the first branch directional well.
And (3) after the discharging condition of the brine at the bottom of the cavity of the second well reaches the target condition, plugging the deflecting section of the first branch directional well by adopting a method similar to the step (206) to complete the expansion of the second well.
Referring to fig. 7, fig. 7 is a schematic diagram of a salt cavern gas storage after expansion of two gas storage wells is completed, as shown in fig. 7, a portion below a certain portion of a deflecting section of a first branch directional well is plugged, as shown in a black plugging portion in fig. 7.
212. And sidetrack a second branch directional well above a second deflecting point of the first branch directional well, the second branch directional well being drilled to the bottom of the cavity of the third well, the second deflecting point being located above the first deflecting point.
Wherein the second deflecting point is the starting point of the deflecting section of the first branch directional well. The third well is a well except the first well and the second well in the existing multiple wells of the salt cavern gas storage.
In embodiments of the present application, a branch directional well sidetrack above the second kick point is referred to as a second branch directional well. The method of sidetracking the second branch oriented well is the same as that of sidetracking the first branch oriented well. As shown in fig. 7, a third kick-off point above the second kick-off point is selected as the starting point for the kick-off section of the second branch oriented well, and the second branch oriented well is sidetrack drilled to the bottom of the cavity of the third well in communication with a pit (not shown) in the bottom of the cavity of the third well.
213. And a third brine discharge pipe column is arranged in the second branch directional well, and one end of the third brine discharge pipe column is positioned in the bottom of the cavity of the third well.
After the well cementation of the second branch directional well, a third halogen-discharging pipe column can be put into the second branch directional well, and one end of the third halogen-discharging pipe column is positioned at the bottom of the cavity of the third well.
In one possible implementation manner, the third brine pipe column in the second branch directional well is provided with a packer, which is the same as the packer installed by the first brine pipe column in step 203, and will not be described in detail.
In one possible implementation, the end of the third brine discharge string of the second branch directional well at the bottom of the cavity of the third well is provided with a sand control device. The sand control device is the same as the sand control device set in the first brine discharge pipe in step 203, and will not be described in detail.
214. And injecting water into the bottom of the cavity of the third well through the third halogen-discharging pipe column to dissolve salt in the pit at the bottom of the cavity of the third well.
215. And natural gas is injected into the third well, and brine at the bottom of the cavity of the third well is discharged to the ground through a third brine discharge pipe column.
Steps 211 to 215 are similar to steps 206 to 210, and the same parts will not be described again.
The brine at the bottom of the third well is discharged to the ground through a brine discharge pipe column by performing the same plugging and sidetracking operation after the brine at the bottom of the second well is discharged, and then the brine at the bottom of the third well is injected with water and gas by using the same method as the first well and the second well.
For the example in step 201, if there is a fourth well, the same operation as the third well may be performed, and brine at the bottom of the fourth well is discharged to the ground through a brine discharge pipe column, so as to achieve the purpose of multi-well expansion.
According to the embodiment of the application, brine at the bottom of the cavity of the single well can be discharged to the ground, undissolved salt in the pit is re-eroded, the cavity volume of the single well is increased from two aspects, in addition, the adjacent wells can be subjected to the same operation through plugging and sidetracking technologies, and multi-well expansion is achieved.
According to the method provided by the embodiment of the application, the new well is drilled near the existing well of the salt cavern gas storage, the new well is the directional well, so that the new well can be drilled to the bottom of the cavity of the existing well, then the brine discharging pipe column is arranged in the cavity of the existing well, one end of the brine discharging pipe column is enabled to reach the bottom of the cavity of the existing well, when natural gas is injected into the existing well, brine at the bottom of the cavity of the existing well can be driven to enter the brine discharging pipe column until the brine is discharged to the ground, and therefore the space occupied by the brine originally at the bottom of the cavity is left, the volume of the cavity is increased, the capacity of the salt cavern gas storage is increased, and the purpose of expanding the salt cavern gas storage is achieved.
In an exemplary embodiment, there is also provided a smart device, which may be relatively large in difference in configuration or performance, and may include one or more processors (central processing units, CPU) and one or more memories, wherein the memories store at least one program code that is loaded and executed by the processors to implement the methods provided in the above embodiments. Of course, the intelligent device may also have a wired or wireless network interface, a keyboard, an input/output interface, and other components for implementing the functions of the device, which are not described herein.
In an exemplary embodiment, a computer readable storage medium storing at least one program code, such as a memory storing at least one program code, is also provided, where the at least one program code is loaded and executed by a processor to implement the method provided in the above embodiment. For example, the computer readable storage medium may be Read-Only Memory (ROM), random-access Memory (Random Access Memory, RAM), compact disc Read-Only Memory (CD-ROM), magnetic tape, floppy disk, optical data storage device, etc.
The foregoing description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, since it is intended that all modifications, equivalents, improvements, etc. that fall within the spirit and scope of the invention.
Claims (6)
1. A method for expanding a salt cavern gas storage, the method comprising:
drilling a directional well at a target location according to the location of a first well of a salt cavern gas storage, the directional well drilled to the bottom of a cavity of the first well, wherein drilling a directional well at the target location according to the location of the first well of the salt cavern gas storage comprises: determining the target positions of the directional wells to be drilled according to the positions of a plurality of existing wells in the salt cavern gas storage, wherein the plurality of wells comprise the first well, and one directional well is drilled at the target position;
a first brine discharge pipe column is arranged in the directional well, one end of the first brine discharge pipe column is positioned in the bottom of a cavity of the first well, a packer is arranged on the first brine discharge pipe column, and the packer is used for sealing an annular space between the first brine discharge pipe column and a casing pipe of the directional well;
injecting natural gas into the first well, and discharging brine at the bottom of the cavity of the first well to the ground through the first brine discharge pipe column;
plugging a deflecting section of the directional well after the discharging condition of the brine at the bottom of the cavity of the first well reaches a target condition, wherein the target condition is used for measuring whether the brine is discharged or not;
laterally drilling a first branch directional well above a first deflecting point of the directional well, wherein the first branch directional well is drilled to the bottom of a cavity of a second well, the second well is a well except the first well in the existing multiple wells of the salt cavern gas storage, and the first deflecting point is the starting point of a deflecting section of the directional well;
installing a second brine discharge pipe column in the first branch directional well, wherein one end of the second brine discharge pipe column is positioned in the bottom of a cavity of the second well;
injecting the natural gas into the second well, and discharging brine at the bottom of the cavity of the second well to the ground through the second brine discharge pipe column;
plugging a deflecting section of the first branch directional well;
laterally drilling a second branch directional well above a second deflecting point of the first branch directional well, wherein the second branch directional well is drilled to the bottom of a cavity of a third well, the third well is a well except the first well and the second well in the multiple wells, and the second deflecting point is positioned above the first deflecting point;
installing a third brine discharge pipe column in the second branch directional well, wherein one end of the third brine discharge pipe column is positioned in the bottom of a cavity of the third well;
and injecting the natural gas into the third well, and discharging brine at the bottom of the cavity of the third well to the ground through the third brine discharge pipe column.
2. The method of claim 1, wherein prior to injecting natural gas into the first well, the method further comprises:
injecting water into the bottom of the cavity of the first well to dissolve salt in the pit at the bottom of the cavity.
3. The method of claim 2, wherein the injecting water into the bottom of the cavity of the first well comprises any one of:
injecting the water into the bottom of the cavity of the first well through the first brine discharge pipe column;
and injecting the water into the bottom of the cavity of the first well through the wellhead of the first well.
4. The method of claim 1, wherein after installing a first brine string and a first packer in the directional well, the method further comprises:
and installing a wellhead device at the wellhead of the directional well, wherein the wellhead device is connected with a brine discharge pipeline on the ground, and the brine discharge pipeline is connected with the first brine discharge pipe column.
5. The method of claim 4, wherein the wellhead is further connected to a surface water injection line, the water injection line being connected to the first brine discharge string.
6. The method of claim 1, wherein an end of the first brine discharge string of the directional well at the bottom of the cavity of the first well is provided with a sand control device for preventing debris in a pit of the bottom of the cavity of the first well from entering the first brine discharge string.
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| CN117722162A (en) * | 2023-11-24 | 2024-03-19 | 中能建数字科技集团有限公司 | Brine discharge device and brine discharge method for salt cavern gas storage |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5722792A (en) * | 1995-02-28 | 1998-03-03 | Societe Francaise De Stockage Geologique- Geostock | Method of putting a saline cavity under gas |
| CN105863599A (en) * | 2016-04-27 | 2016-08-17 | 重庆大学 | Old well utilization method adopting single-cavity old well as brine-extraction horizontally-butted well |
| CN108798783A (en) * | 2018-06-15 | 2018-11-13 | 中盐金坛盐化有限责任公司 | The new well boring method of gas storage is transformed in the old chamber in salt cave |
| CN109838279A (en) * | 2017-11-24 | 2019-06-04 | 江苏苏盐井神股份有限公司 | A method of salt cave storage cavern utilization rate is improved from bottom of chamber row's halogen using connected well |
| CN111550204A (en) * | 2020-06-04 | 2020-08-18 | 天津森特聚尔新能源技术有限公司 | Directional well butt-joint navigation conveying system for high-temperature salt well and application method |
| CN112228071A (en) * | 2020-09-29 | 2021-01-15 | 中国科学院武汉岩土力学研究所 | Method for detecting gas storage performance of brine mining dissolution cavity of high-impurity salt mine |
-
2021
- 2021-02-24 CN CN202110208377.6A patent/CN114961673B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5722792A (en) * | 1995-02-28 | 1998-03-03 | Societe Francaise De Stockage Geologique- Geostock | Method of putting a saline cavity under gas |
| CN105863599A (en) * | 2016-04-27 | 2016-08-17 | 重庆大学 | Old well utilization method adopting single-cavity old well as brine-extraction horizontally-butted well |
| CN109838279A (en) * | 2017-11-24 | 2019-06-04 | 江苏苏盐井神股份有限公司 | A method of salt cave storage cavern utilization rate is improved from bottom of chamber row's halogen using connected well |
| CN108798783A (en) * | 2018-06-15 | 2018-11-13 | 中盐金坛盐化有限责任公司 | The new well boring method of gas storage is transformed in the old chamber in salt cave |
| CN111550204A (en) * | 2020-06-04 | 2020-08-18 | 天津森特聚尔新能源技术有限公司 | Directional well butt-joint navigation conveying system for high-temperature salt well and application method |
| CN112228071A (en) * | 2020-09-29 | 2021-01-15 | 中国科学院武汉岩土力学研究所 | Method for detecting gas storage performance of brine mining dissolution cavity of high-impurity salt mine |
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