CN114517667B

CN114517667B - Water injection method and device for water injection well group

Info

Publication number: CN114517667B
Application number: CN202011299358.0A
Authority: CN
Inventors: 刘阳进; 赵昕铭; 夏敏敏; 李鹏; 麻建军; 高蕊
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2024-05-28
Anticipated expiration: 2040-11-18
Also published as: CN114517667A

Abstract

The application discloses a water injection method and device for a water injection well group, and relates to the technical field of oilfield development. The upper computer can combine the plurality of water injection well groups into a number threshold number of water injection well groups according to the similarity of every two water injection well groups in the plurality of water injection well groups to be combined. Because the similarity of every two water injection well groups is used for reflecting the proximity degree of the wellhead pressure between the two water injection well groups and the construction cost of the water injection pipeline between the two water injection well groups, compared with manual division, the method provided by the application has the advantages that the proximity degree of the wellhead pressure of each water injection well included in each water injection well group obtained by combining the method is higher, the construction cost of the water injection pipeline between each water injection well is lower, namely the water injection well groups obtained by combining the method provided by the application are more reasonable, and thus the water injection cost can be effectively reduced in the water injection process of the water injection well groups.

Description

Water injection method and device for water injection well group

Technical Field

The application relates to the technical field of oilfield development, in particular to a water injection method and device for a water injection well group.

Background

In the middle and later stages of oil and gas exploitation, water can be injected into a production layer through a plurality of water injection wells so as to drive crude oil in the production layer to the position of the production well, thereby improving the recovery ratio of the production well. In the process of injecting water into a production zone, because of the difference of wellhead pressure of each water injection well, the water injection wells can be divided into a high-pressure water injection well group and a low-pressure water injection well group, and then the high-pressure water injection well group and the low-pressure water injection well group are injected with different water injection pressures respectively. The wellhead pressure can be oil pressure or casing pressure of a water injection well. The injection pressure may be greater than or equal to the wellhead pressure of the injection well.

In the related art, a worker may divide the plurality of water injection wells into a high pressure water injection well group and a low pressure water injection well group based on working experience. However, the high-pressure water injection well group and the low-pressure water injection well group obtained by the dividing method are low in rationality, so that the cost for injecting water into the high-pressure water injection well group and the low-pressure water injection well group is high.

Disclosure of Invention

The application provides a water injection method and device for a water injection well group, which can solve the problem that the high-pressure water injection well group and the low-pressure water injection well group obtained by dividing the related technologies are low in rationality, so that the cost of water injection to the high-pressure water injection well group and the low-pressure water injection well group is high. The technical scheme is as follows:

in one aspect, a method of flooding a flooding well group is provided, the method comprising:

executing at least one well combination flow for a plurality of water injection well groups to be combined until the number of updated water injection well groups reaches a number threshold;

injecting water into the updated water injection well groups respectively;

Wherein the well combination and flow comprises:

Determining the similarity of every two water injection well groups in the plurality of water injection well groups, wherein the similarity of the two water injection well groups is used for reflecting the proximity degree of wellhead pressure of the two water injection well groups and the construction cost of a water injection pipeline between the two water injection well groups;

combining two water injection well groups with highest similarity in the plurality of water injection well groups into one water injection well group to obtain an updated water injection well group.

Optionally, the determining the similarity of each two water injection well groups in the plurality of water injection well groups includes:

For each two water injection well groups, determining the similarity of the two water injection well groups based on the sum of water injection loss after the two water injection well groups are combined and water injection pipeline construction cost between the two water injection well groups, wherein the water injection loss after the two water injection well groups are inversely related to the proximity degree of wellhead pressure of the two water injection wells.

Optionally, the method further comprises:

based on wellhead pressure and unit water injection amount of each water injection well in the two water injection well groups, unit operation days of the water injection well, motor efficiency and electricity utilization unit price of a water injection pump for injecting water to the water injection well, determining water injection loss K ₁ after combining the two water injection wells, wherein the water injection loss K ₁ meets the following conditions:

Wherein P _max is the maximum wellhead pressure of the wellhead pressures of each water injection well in the two water injection well groups, the two water injection well groups comprise a first water injection well group and a second water injection well group, P _i ^x is the wellhead pressure of the ith water injection well in the first water injection well group, For the wellhead pressure of the j-th water injection well in the second water injection well group,/>For the maximum wellhead pressure of the wellhead pressures of the individual water injection wells in the first water injection well group,/>For the maximum wellhead pressure of the wellhead pressures of the individual water injection wells in the second water injection well group,/>For the unit water injection amount of the ith first water injection well in the first water injection well group,And (3) the unit water injection amount of the j-th second water injection well in the second water injection well group is T, a is the electricity utilization unit price, and eta is the motor efficiency.

Optionally, the method further comprises:

Determining water injection pipeline construction cost K ₂ between the two water injection well groups based on the distance between the two water injection well groups, the pipeline comprehensive unit price and the return on investment period, wherein the water injection pipeline construction cost K ₂ meets the following conditions:

wherein b is the length coefficient of the pipeline, D is the distance, c is the comprehensive unit price of the pipeline, and m is the return on investment period.

Optionally, the method further comprises:

For each first water injection well, determining the distance between the first water injection well and each second water injection well to obtain a plurality of distances, wherein the first water injection well and the second water injection well respectively belong to the two water injection well groups;

And determining the minimum distance among the plurality of distances as the distance between the two water injection well groups.

Optionally, the method further comprises:

and determining a plurality of water injection well groups communicated with the same water injection trunk line as the plurality of water injection well groups to be combined.

In another aspect, there is provided a water injection apparatus for a water injection well group, the apparatus comprising:

The merging module is used for executing at least one well combination flow for a plurality of water injection well groups to be merged until the number of updated water injection well groups reaches a number threshold;

the water injection module is used for injecting water into the updated water injection well groups respectively;

Wherein the well combination and flow comprises:

Optionally, the merging module is configured to:

Optionally, the apparatus further includes:

The first determining module is configured to determine, based on wellhead pressure and unit water injection amount of each water injection well in the two water injection well groups, unit operation days of the water injection wells, motor efficiency and electricity utilization unit price of a water injection pump for injecting water into the water injection wells, water injection loss K ₁ after the two water injection wells are combined, and water injection loss K ₁ satisfies:

Optionally, the apparatus further includes:

The second determining module is configured to determine a water injection pipeline construction cost K ₂ between the two water injection well groups based on the distance between the two water injection well groups, the pipeline comprehensive unit price and the return on investment period, where the water injection pipeline construction cost K ₂ meets the following conditions:

Optionally, the apparatus further includes:

the third determining module is used for determining the distance between each first water injection well and each second water injection well for each first water injection well to obtain a plurality of distances, and the first water injection well and the second water injection well respectively belong to the two water injection well groups;

And the fourth determining module is used for determining the minimum distance among the plurality of distances as the distance between the two water injection well groups.

Optionally, the apparatus further includes:

and the fifth determining module is used for determining a plurality of water injection well groups communicated with the same water injection trunk line as the plurality of water injection well groups to be combined.

In yet another aspect, a water injection method apparatus for a water injection well group is provided, the apparatus comprising: a processor, a memory, and a computer program stored on the memory and executable on the processor, which when executed implements a method of flooding a flooding well group as described in the above aspects.

In yet another aspect, a computer readable storage medium having instructions stored therein that, when run on a computer, cause the computer to perform a method of flooding a flooding well group as described in the above aspect is provided.

In yet another aspect, there is provided a computer program product comprising instructions which, when run on the computer, cause the computer to perform the water flooding method of the water flooding well group of the above aspect.

The technical scheme provided by the application has the beneficial effects that at least:

the application provides a water injection method and a water injection device for water injection well groups, wherein an upper computer can combine a plurality of water injection well groups into a plurality of water injection well groups with a threshold number according to the similarity of every two water injection well groups in the plurality of water injection well groups to be combined. Because the similarity of every two water injection well groups is used for reflecting the proximity degree of the wellhead pressure of the two water injection well groups and the construction cost of the water injection pipeline between the two water injection well groups, compared with manual division, the method provided by the application has the advantages that the proximity degree of the wellhead pressure of each water injection well included in each water injection well group is higher, the construction cost of the water injection pipeline between each water injection well is lower, namely the water injection well groups obtained by combining the method provided by the application are more reasonable, and thus the water injection cost can be effectively reduced in the water injection process of the water injection well groups.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and 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 water injection method for a water injection well group provided by an embodiment of the present application;

FIG. 2 is a flow chart of another method of flooding a water flooding well group provided in an embodiment of the present application;

FIG. 3 is a flow chart of a method for determining the similarity of two water injection well groups according to an embodiment of the present application;

FIG. 4 is a block diagram of a water injection device for a water injection well group according to an embodiment of the present application;

FIG. 5 is a block diagram of another water injection device for a water injection well group according to an embodiment of the present application;

fig. 6 is a block diagram of a water injection device for a water injection well group according to an embodiment of the present application.

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 with reference to the accompanying drawings.

The embodiment of the application provides a water injection method of a water injection well group, which can be applied to an upper computer. Referring to fig. 1, the method may include:

And 101, executing at least one well combination combining process on a plurality of water injection well groups to be combined until the number of updated water injection well groups reaches a number threshold.

The well combination and flow may include: and determining the similarity of every two water injection well groups in the plurality of water injection well groups, combining the two water injection well groups with the highest similarity in the plurality of water injection well groups into one water injection well group, and obtaining the updated water injection well group.

The similarity of the two water injection well groups can be used for reflecting the proximity degree of wellhead pressure of the two water injection well groups and the construction cost of a water injection pipeline between the two water injection well groups. And, the similarity of two water injection well groups may be positively correlated with the proximity of the wellhead pressure of the two water injection well groups. The similarity of two water injection well groups is inversely related to the construction cost of water injection pipelines between the two water injection well groups.

The similarity of the two water injection well groups not only can reflect the approach degree of the wellhead pressure between the two water injection well groups, but also can reflect the construction cost of the water injection pipeline between the two water injection well groups, and the similarity is positively correlated with the approach degree of the wellhead pressure of the two water injection well groups and negatively correlated with the construction cost of the water injection pipeline between the two water injection well groups. The upper computer can combine the plurality of water injection well groups to be combined by taking the approach degree of the wellhead pressure of each two water injection well groups and the construction cost of the water injection pipeline as measurement indexes. Therefore, in the water injection well group obtained by combining based on the similarity, the approach degree of the wellhead pressure of each water injection well is higher, and the construction cost of the water injection pipeline is lower, so that the wellhead throttling loss of the water injection well group can be reduced in the water injection process of the combined water injection well group, the water injection loss can be reduced, and the effect of effectively reducing the water injection cost is achieved.

And 102, injecting water into the updated water injection well groups respectively.

And after the upper computer determines that the number of the updated water injection well groups reaches the number threshold, the updated water injection well groups can be injected with water respectively.

In summary, the embodiment of the present application provides a water injection method for water injection well groups, where an upper computer may combine a plurality of water injection well groups into a number of threshold water injection well groups according to a similarity of every two water injection well groups in the plurality of water injection well groups to be combined. Because the similarity of every two water injection well groups is used for reflecting the proximity degree of the wellhead pressure of the two water injection well groups and the construction cost of the water injection pipeline between the two water injection well groups, compared with manual division, the method provided by the embodiment of the application has the advantages that the proximity degree of the wellhead pressure of each water injection well included in each water injection well group is higher, the construction cost of the water injection pipeline between each water injection well is lower, namely the water injection well groups obtained by the method provided by the embodiment of the application are more reasonable, and thus the water injection cost can be effectively reduced in the water injection process of the water injection well groups.

Fig. 2 is a flow chart of another water injection method for a water injection well group according to an embodiment of the present application, where the method may be applied to an upper computer. Referring to fig. 2, the method may include:

Step 201, determining a plurality of water injection well groups communicated with the same water injection trunk line as a plurality of water injection well groups to be combined.

An oilfield typically has a plurality of water injection trunks, each of which may be in communication with a plurality of water injection well groups. Before the water injection of the water injection well groups is needed, the upper computer can determine the water injection well groups communicated with the same water injection trunk line, and determine the water injection well groups as the water injection well groups to be combined, so that the water injection efficiency and feasibility of the water injection well groups to be combined are improved. Wherein, in a plurality of water injection well groups communicated with the same water injection trunk line, each water injection well group can comprise at least one water injection well. For example, each water injection well group may include one water injection well.

That is, prior to flooding the plurality of flooding wellheads, the host computer may group the plurality of flooding wellheads in the field based on the flooding trunk, and the grouping may include a plurality of flooding wellheads to be combined for each group. Then, for each group, the upper computer can adopt the method provided by the embodiment of the application to combine the plurality of water injection well groups to be combined in the group, and after the combination is completed, water injection is performed for the combined water injection well groups.

Optionally, a correspondence between the identifiers of the water injection trunk lines and the identifiers of the water injection well groups is stored in the upper computer, and for each water injection trunk line, the upper computer can determine, based on the identifier of the water injection trunk line, identifiers of a plurality of water injection well groups corresponding to the identifier of the water injection trunk line from the correspondence, and determine the water injection well groups indicated by the identifiers of the plurality of water injection well groups as a plurality of water injection well groups to be combined.

Wherein the identity of the water injection trunk line may be the name or number of the water injection trunk line. The identification of the water injection well group may also be the name or number of the water injection well group (which may also be referred to as a well number).

Step 202, determining the similarity of every two water injection well groups in the plurality of water injection well groups to be combined.

After the upper computer determines the plurality of water injection well groups to be combined, the similarity of every two water injection well groups in the plurality of water injection well groups to be combined can be determined.

The similarity of the two water injection well groups is used for reflecting the proximity degree of wellhead pressure of the two water injection well groups and the construction cost of water injection pipelines between the two water injection well groups. The similarity of the two water injection well groups may be positively correlated to the proximity of the wellhead pressure of the two water injection well groups and negatively correlated to the cost of water injection pipe construction between the two water injection well groups.

That is, the higher the proximity of the wellhead pressures of the two water injection well groups (i.e., the smaller the wellhead pressure difference of the two water injection well groups), the higher the similarity of the two water injection well groups. The lower the proximity of the wellhead pressures of the two water injection well groups (i.e., the greater the wellhead pressure difference of the two water injection well groups), the lower the similarity of the two water injection well groups. The lower the construction cost of the water injection pipeline between the two water injection well groups is, the higher the similarity of the two water injection well groups is. The higher the construction cost of the water injection pipeline between the two water injection well groups, the lower the similarity of the two water injection well groups.

The similarity of the two water injection well groups can reflect the approach degree of the wellhead pressure between the two water injection well groups and the construction cost of the water injection pipeline between the two water injection well groups, and the similarity is positively correlated with the approach degree of the wellhead pressure of the two water injection well groups and negatively correlated with the construction cost of the water injection pipeline between the two water injection well groups. Therefore, in the water injection well group obtained based on the similarity combination, the approach degree of the wellhead pressure of each water injection well is higher, and the construction cost of the water injection pipeline is lower, so that the wellhead throttling loss of the water injection well group can be reduced in the water injection process of the combined water injection well group, the water injection loss can be reduced, and the effect of effectively reducing the water injection cost is achieved.

Fig. 3 is a flowchart of a method for determining the similarity of two water injection well groups according to an embodiment of the present application. Referring to fig. 3, the process of determining the similarity of each two water injection well groups in the plurality of water injection well groups to be combined by the upper computer may include:

Step 2021, for each two water injection well groups of the plurality of water injection well groups, acquiring wellhead pressure and unit water injection rate of each water injection well of the two water injection well groups.

After determining a plurality of water injection well groups to be combined, the upper computer can acquire the wellhead pressure and unit water injection quantity of each water injection well in the two water injection well groups for each two water injection well groups in the plurality of water injection well groups. The wellhead pressure and unit water injection rate of each water injection well in the two water injection well groups can be the same or different. The unit water injection amount may be a daily water injection amount.

Alternatively, a pressure sensor and a flow sensor may be installed at the wellhead of each water injection well. The pressure sensor can be used for detecting the wellhead pressure of the water injection well and sending the detected wellhead pressure to an upper computer. Correspondingly, the upper computer can acquire the wellhead pressure of the water injection well. The flow sensor can be used for detecting the unit water injection amount of the water injection well and sending the detected unit water injection amount to an upper computer. Correspondingly, the upper computer can acquire the daily water injection quantity of the water injection well.

For example, a first water injection well group X of the two water injection well groups comprises: x ₁,x₂,…,x_i total i water injection wells, a second water injection well group Y of the two water injection well groups comprising: y ₁,y₂,…,y_j total j water injection wells. The wellhead pressure of the first water injection well in the first water injection well group X obtained by the upper computer can be P ₁ ^x, and the unit water injection quantity isThe wellhead pressure of the ith water injection well is P _i ^x, and the unit water injection rate is/>Namely, the wellhead pressure of each water injection well in the first water injection well group acquired by the upper computer can be sequentially P ₁ ^x,P₂ ^x, … and P _i ^x, and the unit water injection rate is sequentially/>/>Wherein i is a positive integer.

The wellhead pressure of the first water injection well in the second water injection well group Y obtained by the upper computer can be P ₁ ^y, and the unit water injection quantity isThe wellhead pressure of the j-th water injection well is P _j ^y, and the unit water injection rate is/>Namely, the wellhead pressure of each water injection well in the second water injection well group acquired by the upper computer can be sequentially P ₁ ^y,P₂ ^y,…,P_j ^y, and the unit water injection quantity is sequentially/>AndWherein j is a positive integer.

Step 2022, obtaining the unit operation days of the water injection well, the motor efficiency of the water injection pump for injecting water into the water injection well and the electricity utilization unit price.

For every two water injection well groups in the plurality of water injection well groups to be combined, the upper computer can also obtain the unit operation days of each water injection well in the two water injection well groups, the motor efficiency of the water injection pump for injecting water into the water injection well and the electricity utilization unit price. The unit operation days of each water injection well can be the same, and the unit operation days can be annual operation days.

Optionally, the number of days of unit operation of the water injection well, the motor efficiency of the water injection pump for injecting water into the water injection well and the electricity utilization unit price can be stored in advance by the upper computer. Or the unit operation days of the water injection well, the motor efficiency of the water injection pump for injecting water into the water injection well and the electricity utilization unit price can be all obtained by the upper computer in response to the input operation of the staff.

For example, the number of days per unit operation may be 360 days, the motor efficiency of the water injection pump for injecting water into the water injection well may be 80%, and the unit power consumption unit price may be 0.8 yuan/degree.

Step 2023, determining water injection loss after combining the two water injection wells based on wellhead pressure and unit water injection amount of each water injection well in the two water injection well groups, unit operation days of the water injection wells, motor efficiency of a water injection pump for injecting water into the water injection wells, and electricity utilization unit price.

In the embodiment of the application, after acquiring the wellhead pressure and the unit water injection amount of each water injection well, the upper computer can determine the maximum wellhead pressure of the wellhead pressure of each water injection well in the first water injection well group, the maximum wellhead pressure of the wellhead pressure of each water injection well in the second water injection well group, and the maximum wellhead pressure of the wellhead pressure of each water injection well in the two water injection well groups.

And then, the upper computer can determine the water injection loss K ₁ after combining the two water injection wells based on the wellhead pressure and unit water injection amount of each water injection well, the maximum wellhead pressure of the wellhead pressure of each water injection well in the first water injection well group of the two water injection well groups, the maximum wellhead pressure of the wellhead pressure of each water injection well in the second water injection well group, the maximum wellhead pressure of the wellhead pressure of each water injection well in the two water injection well groups, the unit operation days of the water injection wells, the motor efficiency of the water injection pump and the electricity utilization unit price. Wherein, this water injection loss K ₁ can satisfy:

In the formula (1), P _i ^x is the wellhead pressure of the ith water injection well in the first water injection well group of the two water injection well groups, and the unit is megapascals (MPa). The wellhead pressure of the j-th water injection well in the second water injection well group is expressed as MPa.The maximum wellhead pressure in MPa is the wellhead pressure of each water injection well in the first water injection well group. I.e./>The method meets the following conditions: /(I)Wherein P ₁ ^x,P₂ ^x, …, and P _i ^x are wellhead pressures of each water injection well in the first water injection well group in sequence.

The maximum wellhead pressure in MPa is the wellhead pressure of each water injection well included in the second water injection well group. I.e./>The method meets the following conditions: /(I)Wherein P ₁ ^y,P₂ ^y,…,P_j ^y is the wellhead pressure of each water injection well in the second water injection well group in turn. P _max is the maximum water injection pressure of the water injection pressure of each water injection well in the two water injection well groups, and the unit is MPa. Namely, P _max satisfies the following conditions: /(I)

The unit water injection amount of the ith water injection well in the first water injection well group is cubic meter per day (m ³/d). /(I)The unit water injection quantity of the jth water injection well in the second water injection well group is m ³/d, T is the unit operation days, a is the unit power unit price, the unit is the unit/degree, and eta is the motor efficiency.

Step 2024, obtaining the distance between the two water injection well groups.

In the embodiment of the application, for each two water injection well groups in the plurality of water injection well groups to be combined, the upper computer can also acquire the distance between the two water injection well groups before determining the similarity of the two water injection well groups.

In an alternative implementation, if each of the two water injection well groups includes one water injection well, the upper computer may directly determine the distance between the two water injection wells as the distance between the two water injection well groups.

In another alternative implementation, if there is at least one water injection well group of the two water injection well groups, the at least one water injection well group includes a plurality of water injection wells. The process of the upper computer obtaining the distance between the two water injection well groups may include:

And S1, determining the distance between each first water injection well and each second water injection well for each first water injection well to obtain a plurality of distances.

For each first water injection well included in one of the two water injection well groups, the host computer may determine a distance between the first water injection well and each second water injection well, thereby obtaining a plurality of distances. The second water injection well belongs to the other water injection well group of the two water injection well groups. That is, the first water injection well and the second water injection well respectively belong to two water injection well groups.

For example, assume that one of two water injection well groups, X, includes: x ₁ and x ₂ together comprise two first water injection wells, and the other water injection well group Y of the two water injection well groups comprises: y ₁ and y ₂ together. The upper computer may determine the distance D11 between x1 and y1, the distance D12 between x1 and y2, the distance D21 between x2 and y1, and the distance D22 between x2 and y 2.

And S2, determining the minimum distance among the plurality of distances as the distance between the two water injection well groups.

After the distances are obtained, the upper computer can compare the distances to determine the smallest distance among the distances, and the smallest distance is determined as the distance between two water injection well groups. I.e. the distance D between two water injection well groups may satisfy: d=min (Dij), which is the distance between the ith first water injection well and the jth second water injection well in the two water injection well groups.

In an embodiment of the present application, the process of determining the distance between two water injection wells by the upper computer may include: the upper computer may obtain the position of each of the two water injection wells, for example, the coordinates of each water injection well in the geodetic coordinate system. And then, the upper computer can determine the distance between the two water injection wells based on the positions of the two water injection wells.

By way of example, assume that the host computer determines a plurality of distances includes: d11, D12, D21, and D22, and the minimum value of D11, D12, D21, and D22 determined by the upper computer is D22. The host computer may determine D22 as the distance between the first and second water-filled well groups.

Step 2025, determining a water injection pipeline construction cost between the two water injection well groups based on the distance between the two water injection well groups, the pipeline integrated unit price, and the return on investment period.

After the upper computer determines the distance between the two water injection well groups, the construction cost K ₂ of the water injection pipeline between the two water injection well groups can be determined based on the distance between the two water injection well groups, the comprehensive unit price of the pipeline and the return on investment period. Wherein, this water injection pipeline construction cost K ₂ can satisfy:

Wherein b is the length coefficient of the pipeline, D is the distance, and the unit is meter (m). c is the comprehensive unit price of the pipeline, and the unit is per meter (yuan/m). n is the return on investment period. The length coefficient of the pipeline can be used for reflecting the bending degree of the water injection pipeline between two water injection well groups, and the length coefficient is positively correlated with the bending degree. That is, the higher the degree of bending, the greater the length factor of the pipe. The smaller the degree of bending, the smaller the length factor of the pipe.

Alternatively, the length coefficient b of the pipeline, the comprehensive unit price c of the pipeline, and the return on investment period m may be pre-stored in the host computer. Or the length coefficient b of the pipeline, the comprehensive unit price c of the pipeline and the return on investment period m can be obtained by the upper computer in response to the input operation of the staff.

For example, the length coefficient b of the pipeline is 1.2, the comprehensive unit price c of the pipeline is 40 ten thousand yuan/kilometer, namely 40 yuan/meter, and the return on investment period n is 5.

Step 2026, determining the similarity of the two water injection well groups based on the sum of the water injection loss after combining the two water injection well groups and the water injection pipeline construction cost between the two water injection well groups.

For every two water injection well groups in the plurality of water injection well groups, after determining water injection loss after combining the two water injection well groups and water injection pipeline construction cost between the two water injection well groups, the upper computer can determine the similarity of the two water injection well groups based on the sum of the water injection loss and the water injection pipeline construction cost.

The similarity of the two water injection well groups is inversely related to the water injection loss after the two water injection well groups are combined. The loss of water injection after the two water injection well groups are combined is inversely related to the proximity of the wellhead pressure of the two water injection well groups. That is, the higher the proximity of the wellhead pressure of the two water injection well groups, the smaller the water injection loss after the two water injection well groups are combined, and correspondingly, the higher the similarity of the two water injection well groups. The lower the proximity of the wellhead pressure of the two water injection well groups, the higher the water injection loss after the two water injection well groups are combined, and correspondingly, the lower the similarity of the two water injection well groups.

In the embodiment of the application, the upper computer can determine the similarity index between two water injection well groups based on the combined water injection loss of the two water injection well groups and the sum of the construction cost of the water injection pipelines. The similarity index may be used to reflect the similarity of two water-filled well groups, which may be inversely related to the similarity index. That is, the greater the similarity index, the lower the similarity between two water injection well groups. The smaller the similarity index, the higher the similarity between two water injection well groups.

Optionally, the similarity index may be equal to a sum of water injection loss after combining the two water injection wells and water injection pipeline construction costs between the two water injection well groups.

Or the similarity index K may be equal to the product of the sum of the water injection loss K ₁ after combining the two water injection wells and the water injection pipeline construction cost K ₂ between the two water injection well groups and the specified coefficient C. That is, the similarity index K may satisfy:

in the formula (3), the specified coefficient may be stored in advance in the mobile terminal. For example, the specified coefficient may be 10000, and accordingly, the similarity index K may satisfy:

And 203, combining two water injection well groups with highest similarity in the plurality of water injection well groups to be combined into one water injection well group to obtain an updated water injection well group.

After determining the similarity of every two water injection well groups in the plurality of water injection well groups to be combined, the upper computer can combine the two water injection well groups with the highest similarity, namely the two water injection well groups with the highest combining feasibility into one water injection well group, so as to obtain the updated water injection well group.

In the embodiment of the application, after obtaining the similarity indexes of each two water injection well groups in the plurality of water injection well groups to be combined, the upper computer can compare the sizes of the plurality of similarity indexes to determine the smallest similarity index in the plurality of similarity indexes, and combine the two water injection well groups corresponding to the smallest similarity index into one water injection well group.

Step 204, detecting whether the number of the updated water injection well groups reaches a number threshold.

After the updated water injection well group is obtained, the upper computer can determine the number of the updated water injection well group. And then, the upper computer can detect whether the number of the updated water injection well groups reaches a number threshold value. If the upper computer determines that the number of the updated water injection well groups does not reach the number threshold, that is, the number of the updated water injection well groups is still greater than the number threshold, the upper computer may continue to execute step 202.

If the upper computer determines that the number of the updated water injection well groups reaches the number threshold, that is, the number of the updated water injection well groups is equal to the number threshold, step 205 may be executed.

The number threshold may be stored in advance in the upper computer. For example, the number threshold may be 2.

And 205, injecting water into the updated water injection well groups respectively.

In the embodiment of the application, after the upper computer determines that the number of the updated water injection well groups reaches the number threshold, the water injection equipment can be controlled to inject water into the updated water injection well groups respectively.

For example, the number threshold is 2, i.e., the number of updated water injection well groups is 2. One of the two updated water injection well groups can be a high-pressure water injection well group, and the other water injection well group can be a low-pressure water injection well group. The maximum wellhead pressure of the wellhead pressure of each water injection well in the high pressure water injection well group is greater than the maximum wellhead pressure of the wellhead pressure of each water injection well in the low pressure water injection well group.

Because each water injection well in the two water injection well groups is communicated with the same water injection trunk line before water injection, the upper computer can display the identification of each water injection well in the high-pressure water injection well group or the identification of each water injection well in the low-pressure water injection well group before water injection. The staff can add a water injection trunk line, and can communicate each water injection well included in the high-pressure water injection well group with the added water injection trunk line based on the identification of the water injection well displayed by the upper computer, or communicate each water injection well included in the low-pressure water injection well group with the added water injection trunk line. I.e. each water injection well in the high pressure water injection well group and each water injection well in the low pressure water injection well group are respectively communicated with different water injection main lines.

Then, the upper computer can control water injection equipment, such as a water injection pump, to inject water to the high-pressure water injection well group and the low-pressure water injection well group through the two water injection main lines respectively at different water injection pressures. For example, the host computer may control the first water injection pump to inject water into the high pressure water injection well group at a first injection pressure and control the second water injection pump to inject water into the low pressure water injection well group at a second injection pressure. The first injection pressure may be greater than or equal to a maximum wellhead pressure of wellhead pressures of each of the injection wells in the high pressure injection well group. The second injection pressure may be greater than or equal to a maximum wellhead pressure of wellhead pressures of individual injection wells in the low pressure injection well group.

The method provided by the embodiment of the application is exemplified by the number of the plurality of water injection well groups to be combined being 7, the unit water injection amount of each water injection well being daily water injection amount, the unit operation time being 360 days, the motor efficiency being 80%, the electricity utilization unit price being 0.8 yuan/degree, the length coefficient of the pipeline being 1.2, and the comprehensive unit of the pipeline being 40 yuan/m.

Assume that each of the seven water injection well groups includes 1 water injection well, and the wellhead pressure and daily water injection rate of each water injection well are shown in table 1. As can be seen from Table 1, the wellhead pressure of the water injection well 1# is 3.0MPa, and the daily water injection rate is 100m ³/d. The wellhead pressure of the water injection well No. 5 is 7.2MPa, and the daily water injection rate is 150m ³/d. The wellhead pressure of the water injection well 7# is 8.5MPa, and the daily water injection rate is 160m ³/d.

TABLE 1

Well number	1#	2#	3#	4#	5#	6#	7#
								Wellhead pressure (MPa)	3.0	4.5	5.0	5.5	7.2	7.5	8.5
Daily injection quantity (m ³/d)	100	200	350	120	150	120	160

The distance between every two water injection wells in the 7 water injection wells can be shown in table 2, and as can be seen from table 2, the distance between the water injection well 1# and the water injection well 2# is 616m, the distance between the water injection well 1# and the water injection well 5# is 246m, and the distance between the water injection well 6# and the water injection well 7# is 732m.

TABLE 2

And then, the upper computer can determine the similarity index between every two water injection well groups in the seven water injection well groups determined by the upper computer according to the formula (1), the formula (2) and the formula (4). Wherein, the similarity index K of the water injection well group (1#) and the water injection well group (2#) in the seven water injection wells meets the following conditions:

Similarly, the similarity index between every two water injection well groups in the seven water injection well groups determined by the upper computer can be shown in table 3, and as can be seen from table 3, the similarity index between the water injection well group (1#) and the water injection well group (5#) is 6.59. The similarity index between the water injection well group (2 # and the water injection well group (5 #) is 10.99. The similarity index between the water injection well group (5 # and the water injection well group (6 #) is 3.27.

TABLE 3 Table 3

After the upper computer determines the similarity index between every two water injection wells in the seven water injection wells shown in table 3, the minimum similarity index in the multiple similarity indexes can be determined to be 3.27, and two water injection well groups corresponding to the similarity index 3.27, namely a water injection well group (5#) and a water injection well group (6#), can be determined to be the two water injection wells with the highest similarity. And then, the upper computer can combine the water injection well group (5 # and the water injection well group (6 #) into one water injection well group, and update the combined water injection well group. The updated water injection well group comprises: the water injection well group (1 #), the water injection well group (2 #), the water injection well group (3 #), the water injection well (4 #), and the water injection well groups (5 # and 6 #) are six water injection well groups in total.

Assuming that the number threshold is 2, the number of the current updated water injection well groups is 6, and because 6 is greater than 2, the upper computer can continuously determine similarity indexes between every two water injection well groups in the six water injection well groups.

For example, the upper computer determines that the water injection loss K ₁ after the water injection well group (7 #) and the water injection well group (5 # and 6 #) are:

the construction cost K ₂ of the water injection pipeline between the water injection well group (7 # and the water injection well groups (5 # and 6 #) is as follows: Afterwards, the upper computer can determine the similarity index K between the water injection well group (7#) and the water injection well groups (5# and 6#) as follows: /(I)

Similarly, the similarity index of every two water injection well groups in the six water injection well groups determined by the upper computer can be shown in table 4. As can be seen from table 4, the similarity index between the water injection well (1 #) and the water injection well group (5 # and 6 #) is 6.86. The similarity index between the water injection well group (3 # and the water injection well groups (5 # and 6 #) is 11.18. The similarity index between the water injection well group (4 # and the water injection well groups (5 # and 6 #) is 6.03.

TABLE 4 Table 4

Similarity index K	1#	2#	3#	4#	(5 # And 6 #)	7#
							1#	0	7.41	5.30	10.95	6.86	10.17
2#		0	9.01	12.68	11.59	9.54
							3#			0	7.31	11.18	19.42
4#				0	6.03	14.21
							(5 # And 6 #)					0	7.56
7#						0

After the upper computer obtains the similarity indexes between every two water injection wells in the six water injection wells shown in table 4, the minimum similarity index in the multiple similarity indexes can be determined to be 5.30, and two water injection well groups corresponding to the similarity index 5.30, namely a water injection well group (1#) and a water injection well group (3#), can be determined to be the two water injection well groups with the highest similarity. And then, the upper computer can combine the water injection well group (1#) and the water injection well group (3#) into one water injection well group, and update the combined water injection well group. The updated water injection well group comprises: water injection well group (1 # and 3 #), water injection well group (2 #), water injection well (4 #), water injection well group (5 # and 6 #) and water injection well group (7 #) are five water injection well groups in total.

Because the number 5 of the current updated water injection well groups is greater than the number threshold value 2, the upper computer can continuously determine the similarity index between every two water injection well groups in the five water injection well groups.

For example, the host computer may determine that the injection loss K ₁ after the injection well group (1 # and 3 #) and the injection well group (5 # and 6 #) are:

the construction cost K ₂ of the water injection pipeline between the water injection well group (1 # and 3 #) and the water injection well group (5 # and 6 #) is as follows:

Thereafter, the host computer may determine a similarity index K between the water injection well groups (1 # and 3 #) and the water injection well groups (5 # and 6 #), the similarity index K being a function of the similarity index

Similarly, the similarity index between every two water injection well groups in the five water injection well groups determined by the upper computer can be shown in table 5. As can be seen from table 5, the similarity index between the water injection well group (1 #, 3 #) and the water injection well group (7 #) is 9.54. The similarity index between the water injection well group (4 # and the water injection well group (5 # and 6 #) is 6.03.

TABLE 5

Similarity index K	2#	(1 # And 3 #)	4#	(5 # And 6 #)	7#
						2#	0	6.91	12.68	11.59	9.54
(1 # And 3 #)		0	7.81	13.61	20.42
						4#			0	6.03	14.21
(5 # And 6 #)				0	7.56
						7#					0

After the upper computer obtains the similarity indexes between every two water injection wells in the five water injection wells shown in table 5, the minimum similarity index in the multiple similarity indexes can be determined to be 6.03, and two water injection well groups corresponding to the similarity index 6.03, namely a water injection well group (4#) and a water injection well group (5# and 6#), are the two water injection well groups with the highest similarity. And then, the upper computer can combine the water injection well group (4 # and the water injection well group (5 # and 6 #) into a water injection well group, and update the combined water injection well group. The updated water injection well group comprises: water injection well group (1 # and 3 #), water injection well group (2 #), water injection well group (4 #, 5# and 6 #) and water injection well group (7 #) are four.

Because the number 4 of the current updated water injection well groups is still greater than the number threshold 2, the upper computer can continuously determine the similarity index between every two water injection well groups in the four water injection well groups, and the similarity index between every two water injection well groups in the four water injection well groups can be shown in table 6.

As can be seen from table 6, the similarity index between the water injection well group (2#) and the water injection well groups (1#, 3#) is 6.91, and the similarity index between the water injection well group (2#) and the water injection well groups (4#, 5# and 6#) is 11.59. The similarity index between the water injection well groups (1 # and 3 #) and the water injection well groups (4 #, 5# and 6 #) was 13.61.

TABLE 6

Similarity index K	2#	(1 # And 3 #)	(4 #, 5# And 6 #)	7#
					2#	0	6.91	11.59	9.54
(1 # And 3 #)		0	13.61	20.42
					(4 #, 5# And 6 #)			0	8.76
7#				0

After the upper computer obtains the similarity indexes between every two water injection wells in the four water injection wells shown in table 5, the minimum similarity index in the multiple similarity indexes can be determined to be 6.91, and two water injection well groups corresponding to the similarity index 6.91, namely a water injection well group (2#) and a water injection well group (1# and 3#), are the two water injection well groups with the highest similarity. And then, the upper computer can combine the water injection well group (2 # and the water injection well group (1 # and 3 #) into a water injection well group, and update the combined water injection well group. The updated water injection well group comprises: water injection well group (1 #, 2# and 3 #), water injection well group (4 #, 5# and 6 #) and water injection well group (7 #) are three.

Because the number 3 of the updated water injection well groups is greater than the number threshold value 2, the upper computer can continuously determine the similarity index between every two water injection well groups in the three water injection well groups. The similarity index between each two of the three water injection well groups may be as shown in table 7.

As can be seen from table 7, the similarity index between the water injection well group (1 #, 2# and 3 #) and the water injection well group (4 #, 5# and 6 #) was 18.61, the similarity index between the water injection well group (1 #, 2# and 3 #) and the water injection well group (7 #) was 24.29, and the similarity index between the water injection well group (4 #, 5# and 6 #) and the water injection well group (7 #) was 8.76.

TABLE 7

Similarity index K	(1 #, 2# And 3 #)	(4 #, 5# And 6 #)	7#
				(1 #, 2# And 3 #)	0	18.61	24.29
(4 #, 5# And 6 #)		0	8.76
				7#			0

The upper computer obtains the similarity index between every two water injection wells in the three water injection wells shown in table 7, compares the similarity indexes, can determine that the smallest similarity index in the similarity indexes is 8.76, and can determine that two water injection well groups corresponding to the similarity index 8.76, namely a water injection well group (7#) and a water injection well group (4#, 5# and 6#), are the two water injection well groups with the highest similarity. And then, the upper computer can combine the water injection well group (7#) and the water injection well group (4#, 5# and 6#) into one water injection well group, and update the combined water injection well group. The updated water injection well group comprises: water injection well groups (1 #, 2# and 3 #), and water injection well groups (4 #, 5#, 6# and 7 #).

Because the number of the updated water injection well groups is equal to the number threshold value, the upper computer determines that water can be injected for the two water injection well groups respectively. Since the maximum water injection pressure of each water injection well in the water injection well group (4#, 5#, 6# and 7#) is 8.5MPa, the maximum water injection pressure of each water injection well in the water injection well group (1#, 2# and 3#) is 5.0MPa. Thus, the water injection well groups (4#, 5#, 6# and 7# are high pressure water injection well groups and the water injection well groups (1#, 2# and 3# are low pressure water injection well groups).

And then, the upper computer can control the first water injection pump to inject water for the water injection well groups (4#, 5#, 6# and 7#) at a water injection pressure greater than or equal to 8.5MPa, and control the second water injection pump to inject water for the water injection well groups (1#, 2# and 3#) at a water injection pressure greater than or equal to 5.0MPa, so that partial pressure water injection of a plurality of water injection well groups to be combined is realized.

Optionally, the sequence of the steps of the water injection method of the water injection well group provided by the embodiment of the application can be properly adjusted, and the steps can be correspondingly increased or decreased according to the situation. For example, step 201 may be deleted as appropriate, i.e. the host computer has determined a plurality of water injection well groups to be combined. Any method that can be easily conceived by those skilled in the art within the technical scope of the present disclosure should be covered in the protection scope of the present application, and thus will not be repeated.

In summary, the embodiment of the present application provides a water injection method for water injection well groups, where an upper computer may combine a plurality of water injection well groups into a number of threshold water injection well groups according to a similarity of every two water injection well groups in the plurality of water injection well groups to be combined. Because the similarity of every two water injection well groups is used for reflecting the approach degree of the wellhead pressure of the two water injection well groups and the construction cost of the water injection pipeline between the two water injection well groups, compared with manual division, the approach degree of the wellhead pressure of each water injection well included in each water injection well group obtained by combining the method provided by the embodiment of the application is higher, and the construction cost of the water injection pipeline between each water injection well is lower, namely the water injection well groups obtained by combining the method provided by the embodiment of the application are more reasonable, so that the water injection cost can be effectively reduced in the water injection process of the water injection well groups.

The embodiment of the application provides a water injection device of a water injection well group, which can be arranged in an upper computer. Referring to fig. 4, the apparatus 300 may include:

The merging module 301 is configured to execute at least one well combination merging process for a plurality of water injection well groups to be merged until the number of updated water injection well groups reaches a number threshold;

the water injection module 302 is configured to inject water into the updated water injection well groups respectively;

Wherein, well combination and flow includes:

determining the similarity of every two water injection well groups in the plurality of water injection well groups, wherein the similarity of the two water injection well groups is used for reflecting the proximity degree of wellhead pressure of the two water injection well groups and the construction cost of water injection pipelines between the two water injection well groups;

Alternatively, the merging module 301 may be configured to:

For every two water injection well groups, the similarity of the two water injection well groups is determined based on the sum of water injection loss after the two water injection well groups are combined and water injection pipeline construction cost between the two water injection well groups, and the water injection loss after the two water injection well groups are inversely related to the proximity degree of wellhead pressure of the two water injection wells.

Optionally, referring to fig. 5, the apparatus 300 may further include:

The first determining module 303 is configured to determine, based on wellhead pressure and unit water injection amount of each water injection well in the two water injection well groups, unit operation days of the water injection wells, motor efficiency and electricity utilization unit price of a water injection pump for injecting water into the water injection wells, water injection loss K ₁ after combining the two water injection wells, where the water injection loss K ₁ satisfies:

Wherein P _max is the maximum wellhead pressure of the wellhead pressures of each water injection well in two water injection well groups, the two water injection well groups comprise a first water injection well group and a second water injection well group, P _i ^x is the wellhead pressure of the ith water injection well in the first water injection well group, For the wellhead pressure of the j-th water injection well in the second water injection well group,/>For the maximum wellhead pressure of the wellhead pressures of the individual water injection wells in the first water injection well group,/>For the maximum wellhead pressure of the wellhead pressures of the individual water injection wells in the second water injection well group,/>For the unit water injection rate of the ith first water injection well in the first water injection well group,/>And (3) the unit water injection quantity of the jth second water injection well in the second water injection well group is T, the unit operation days are T, a is the electricity utilization unit price, and eta is the motor efficiency.

Optionally, the apparatus 300 may further include:

The second determining module 304 is configured to determine a water injection pipeline construction cost K ₂ between two water injection well groups based on a distance between the two water injection well groups, a pipeline comprehensive unit price and a return on investment period, where the water injection pipeline construction cost K ₂ satisfies:

Optionally, the apparatus 300 may further include:

A third determining module 305, configured to determine, for each first water injection well, a distance between the first water injection well and each second water injection well, to obtain a plurality of distances, where the first water injection well and the second water injection well respectively belong to two water injection well groups;

a fourth determination module 306 is configured to determine a minimum distance of the plurality of distances as a distance between two water injection well groups.

Optionally, the apparatus 300 may further include:

a fifth determining module 307 is configured to determine a plurality of water injection well groups communicating with the same water injection trunk line as a plurality of water injection well groups to be combined.

In summary, the embodiment of the application provides a water injection device for water injection well groups, which can combine a plurality of water injection well groups into a number of threshold water injection well groups according to the similarity of every two water injection well groups in the plurality of water injection well groups to be combined. Because the similarity of every two water injection well groups is used for representing the approach degree of the wellhead pressure of the two water injection well groups and the water injection pipeline construction cost between the two water injection well groups, compared with manual division, the device is higher in the approach degree of the wellhead pressure of each water injection well included in each water injection well group, and the water injection pipeline construction cost between each water injection well is lower, namely the water injection well groups obtained by combining the device are more reasonable, so that the water injection cost can be effectively reduced in the water injection process of the water injection well groups.

It will be clearly understood by those skilled in the art that, for convenience and brevity of description, the apparatus and the specific working process of each module described above may refer to the corresponding process in the foregoing method embodiment, which is not repeated herein.

Fig. 6 is a block diagram of a water injection device for a water injection well group according to an embodiment of the present application, and referring to fig. 6, the device 400 may include: a processor 401, a memory 402, and a computer program stored in the memory 402 and executable on the processor 401, the processor 401 may implement a water flooding method of a water flooding well group, such as the method shown in fig. 1 or fig. 2, provided by the above-mentioned method embodiment when executing the computer program.

The embodiment of the application also provides a computer readable storage medium, wherein instructions are stored in the computer readable storage medium, when the computer readable storage medium runs on a computer, the computer is caused to execute the water injection method of the water injection well group provided by the embodiment of the method, for example, the method shown in fig. 1 or fig. 2.

The present application also provides a computer program product containing instructions, which when run on a computer, cause the computer to perform the water injection method of the water injection well group provided by the above method embodiment, for example, the method shown in fig. 1 or fig. 2.

It will be appreciated by those of ordinary skill in the art that all or part of the steps of implementing the above embodiments may be implemented by hardware, or may be implemented by a program to instruct related hardware, and the program may be stored in a computer readable storage medium, where the storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

The foregoing description of the exemplary embodiments of the application is not intended to limit the application to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the application.

Claims

1. A method of flooding a water flooding well group, the method comprising:

injecting water into the updated water injection well groups respectively;

Wherein the well combination and flow comprises:

For each two water injection well groups of the plurality of water injection well groups, determining a similarity of the two water injection well groups based on a sum of water injection loss after two water injection well groups and water injection pipeline construction costs between the two water injection well groups, the water injection loss after two water injection well groups being inversely related to a proximity of wellhead pressures of the two water injection wells, the similarity of the two water injection well groups being used to reflect the proximity of wellhead pressures of the two water injection well groups, and the water injection pipeline construction costs between the two water injection well groups, wherein:

Wherein P _max is the maximum wellhead pressure of the wellhead pressures of each water injection well in the two water injection well groups, the two water injection well groups comprise a first water injection well group and a second water injection well group, P _i ^x is the wellhead pressure of the ith water injection well in the first water injection well group, For the wellhead pressure of the j-th water injection well in the second water injection well group,/>For the maximum wellhead pressure of the wellhead pressures of the individual water injection wells in the first water injection well group,/>For the maximum wellhead pressure of the wellhead pressures of the individual water injection wells in the second water injection well group,/>For the unit water injection rate of the ith first water injection well in the first water injection well group,/>The unit water injection quantity of the j-th second water injection well in the second water injection well group is T, a is the electricity utilization unit price, and eta is the motor efficiency;

Wherein b is the length coefficient of the pipeline, D is the distance, c is the comprehensive unit price of the pipeline, and m is the return on investment period;

2. The method according to claim 1, wherein the method further comprises:

3. The method according to claim 1 or 2, characterized in that the method further comprises:

4. A water injection apparatus for a water injection well group, the apparatus comprising:

Wherein the well combination and flow comprises:

Combining two water injection well groups with highest similarity in the plurality of water injection well groups into one water injection well group to obtain an updated water injection well group;

The merging module is used for:

for each two water injection well groups, determining the similarity of the two water injection well groups based on the sum of water injection loss after the two water injection well groups are combined and water injection pipeline construction cost between the two water injection well groups, wherein the water injection loss after the two water injection well groups are inversely related to the proximity degree of wellhead pressure of the two water injection wells;