Transportation increasing optimization method for outbound pipeline of combination station

Abstract

The invention belongs to the technical field of oil and gas gathering and transportation engineering in the petroleum industry, and particularly relates to a transportation increasing optimization method for an external transportation pipeline of a combination station. The method comprises the following five steps of: establishing a cost target function Fmin including power cost and medicine cost, solving the power cost, solving the medicine cost, solving the minimum value of the sum of the power cost and the medicine cost, and carrying out pipeline external transportation according to the energy consumption of an external transportation pump of the minimum value of the sum of the power cost and the medicine cost and the medicine adding amount. Under the condition that the external transportation pipe diameter of the combination station is not changed, the addition amount of the drag reducer or the pressure of an external transportation pump is controlled based on a cost optimization method, the use amount of the drag reducer is reduced, the operation energy consumption is reduced, the operation cost is reduced, and the oil field benefit is increased while the external transportation of crude oil and the safe operation of a pipeline are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas gathering and transportation engineering in the petroleum industry, and in particular relates to a method for optimizing the increase in transmission of a combined station external transmission pipeline. Background Art

[0002] Some blocks of an oil field are still in the stage of large-scale development and production increase. For the oil field blocks that have been put into production for a period of time, as the output gradually increases, some joint stations are limited in the external transmission volume due to the diameter of the external transmission pipeline, which in turn affects the output of the oil field. When the external transmission volume of the joint station pipeline is limited, increasing the external transmission pressure or adding drag reducers can appropriately increase the external transmission volume. However, this method cannot determine the amount of drag reducers that need to be added or the pressure value that needs to be increased. Furthermore, when the amount of drag reducers added exceeds a certain concentration, no matter how much drag reducers are injected, the transmission efficiency of the external transmission pipeline will no longer increase, which results in a waste of drag reducers and increased ineffective costs. At the same time, the external transmission pressure cannot be increased indefinitely. When the external transmission pressure increases to close to the design pressure of the pipeline, it will affect the safe operation of the pipeline. Summary of the invention

[0003] The present invention provides a method for optimizing the increase in output of a combined station external transmission pipeline, and its purpose is to provide a method based on cost optimization to control the dosage of a drag reducer or the pressure of an external transmission pump under the condition that the diameter of the combined station external transmission pipeline remains unchanged, thereby reducing the amount of drag reducer used, reducing operating energy consumption, reducing operating costs, and increasing oil field benefits while ensuring the external transmission of crude oil and safe operation of the pipeline.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] A method for optimizing the increase in transmission of a combined off-site transmission pipeline comprises the following steps:

[0006] Step 1: Establish a cost objective function F that includes power costs and drug costs min ;

[0007] Step 2: Calculate the power cost;

[0008] Step 3: Calculate the cost of medicines;

[0009] Step 4: Find the minimum value of the sum of power costs and drug costs;

[0010] Step 5: Pipeline external transport is carried out according to the energy consumption of the external transport pump and the amount of added medicine that minimizes the sum of the power cost and the medicine cost obtained in step 4.

[0011] In step 1, the cost objective function is established as F min ,

[0012] F min =S p +Sm

[0013] Where: S p The power cost is the electricity cost generated by the energy consumption of the external pump;

[0014] S m The cost of medicines incurred for adding drag reducing agents.

[0015] The specific method for obtaining the power cost in step 2 is as follows:

[0016] Step 1: Power Cost S p =eW;

[0017] Where: e is the electricity price, yuan / kW·h;

[0018] W is the energy consumption of a single pump, kW·h;

[0019] Energy consumption per pump

[0020]

[0021] Where: N e The effective energy obtained by the pump from the liquid transported per unit time, kW;

[0022] t is the pump operation time, h;

[0023] η is the efficiency of a single pump, dimensionless;

[0024] η e is the motor efficiency, dimensionless;

[0025] ρ is the oil density, kg / m 3 ;

[0026] g is the acceleration due to gravity, 9.8N / kg;

[0027] Q is the volume flow rate of oil flowing through the pump, m 3 / s;

[0028] H is the head provided by the pump at the corresponding output. m ;

[0029] Step 2: If multiple pumps are connected in parallel,

[0030]

[0031] Where: t i is the running time of the oil pump, h;

[0032] n is the number of oil delivery pumps, pieces;

[0033] H iThe head provided for the i-th external pump, m;

[0034] η i is the efficiency of the i-th external delivery pump, dimensionless;

[0035] η ni is the efficiency of the i-th motor, dimensionless;

[0036] δ is the state of the i-th pump, 0 means the pump is off, 1 means the pump is on;

[0037] The third step is to determine the optimal solution for power costs by determining the start and stop states of different pumps, working time t, and pump characteristic curves under the condition of a certain pipeline output volume.

[0038] The outlet head of the external pump

[0039]

[0040] After deformation, it can be converted into the pressure of the pump outlet

[0041]

[0042] Where: ρ is the oil density, kg / m 3 ;

[0043] g is the acceleration due to gravity, 9.8N / kg;

[0044] P d It is the pressure of oil when it passes through the outlet of the external pump;

[0045] Z d It is the elevation of the oil product when it passes through the outlet of the external pump;

[0046] C d It is the flow rate of oil passing through the outlet of the external pump;

[0047] P s It is the pressure of oil when it passes through the inlet of the external transfer pump;

[0048] Z s It is the elevation of the oil when it passes through the inlet of the external transfer pump;

[0049] C s It is the flow rate of the oil when it passes through the inlet of the external pump.

[0050] The specific method for obtaining the drug cost in step 3 is as follows:

[0051] S m =YU;

[0052] Y=g(Q)

[0053] Among them: U is the drug price, yuan / kg;

[0054] Y is the amount of drag reducer added, kg;

[0055] The unit price of the drag reducer is determined, and the amount of drag reducer added Y has a certain correlation with the pipeline pressure drop, that is, the pipeline pressure drop loss; under the condition that the external transmission head remains unchanged, the change of the pipeline pressure drop loss will cause the change of the external transmission displacement. Therefore, the amount of drag reducer added is related to the external transmission displacement. The mutual relationship is determined through field experiments, and the flow rate is determined. According to this flow rate, the optimal amount of drag reducer added can be determined.

[0056] Furthermore, the relationship equation between the pipeline pressure drop loss ΔP and the amount of drag reducer added Y is ΔP=f(Y), which can be determined by field tests and final fitting;

[0057] The relationship between flow rate or flow velocity and pipeline pressure drop can be expressed by the formula

[0058] Sure,

[0059] Therefore, the relationship between the amount of drag reducer added Y and the flow rate or velocity can be determined through field experiments;

[0060] where h f is the head loss along the way,

[0061]

[0062] Where: P m It is the pressure at the outlet of the external transmission pipeline, i.e. the pressure at the end of the external transmission pipeline;

[0063] Z m It is the elevation of the outlet of the external transmission pipeline, i.e. the end of the external transmission pipeline;

[0064] C m is the flow velocity at the outlet of the external transmission pipeline, i.e., the end of the external transmission pipeline;

[0065] P d The pressure at the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump;

[0066] Z d The elevation of the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump;

[0067] C d The flow rate at the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump;

[0068] L is the length of the pipeline, m;

[0069] d is the pipe diameter, m;

[0070] v is the flow rate of the external oil, m / s;

[0071] λ is the drag coefficient along the path, dimensionless.

[0072] The method for obtaining the minimum value of the sum of the power cost and the drug cost in the step 4 is to obtain the combination of the drag reducer addition amount and the power cost under a given flow rate and satisfying the constraint conditions.

[0073] The constraints are: First, the head H at the pump outlet must be greater than the head loss h along the pipeline. f , the sum of local head loss and elevation difference; second, the pressure at the pump outlet must be less than the design pressure or pressure-bearing capacity of the pipeline; third, the daily addition of drag reducer to the external pipeline must not exceed the target dosage set on site.

[0074] Beneficial effects:

[0075] (1) The present invention combines the pipeline pressure drop (pressure drop loss) with the amount of drag reducer to find the optimal solution, thereby achieving scientific dosage and avoiding waste of agents.

[0076] (2) The present invention combines the outlet pressure of the pump with factors such as the external output volume to find the optimal solution, thereby achieving the purpose of reducing energy consumption and improving pump efficiency.

[0077] (3) After the present invention obtains the optimal solution for power cost and chemical addition cost, the optimal operation cost of the combined station external transmission pipeline is achieved.

[0078] (4) In the later stage of the present invention, the solution model can be embedded in the intelligent control system to realize the intelligent addition and adjustment of the drag reducer dosage according to the different pipeline output volumes.

[0079] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0081] Figure 1 It is a flow chart of the present invention.

[0082] Figure 2 This is a relationship diagram between the amount of drag reducer added in the present invention and the power cost of the external transmission pump and the drag reducer cost.

[0083] Figure 3 It is a schematic diagram of the operating cost and the external transmission volume of the combined station pipeline in the present invention. DETAILED DESCRIPTION

[0084] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0085] Example:

[0086] according to Figure 1-Figure 3 A combined station external transmission pipeline increase optimization method shown includes the following steps:

[0087] Step 1: Establish a cost objective function F that includes power costs and drug costs min ;

[0088] Step 2: Calculate the power cost;

[0089] Step 3: Calculate the cost of medicines;

[0090] Step 4: Find the minimum value of the sum of power costs and drug costs;

[0091] Step 5: Pipeline external transport is carried out according to the energy consumption of the external transport pump and the amount of added medicine that minimizes the sum of the power cost and the medicine cost obtained in step 4.

[0092] Preferably, the cost objective function established in step 1 is F min ,

[0093] F min =S p +S m

[0094] Where: S p The power cost is the electricity cost generated by the energy consumption of the external pump;

[0095] S m The cost of medicines incurred for adding drag reducing agents.

[0096] The specific method for obtaining the power cost in step 2 is as follows:

[0097] Step 1: Power Cost S p =eW;

[0098] Where: e is the electricity price, yuan / kW·h;

[0099] W is the energy consumption of a single pump, kW·h;

[0100] Energy consumption per pump

[0101]

[0102] Where: N e The effective energy obtained by the pump from the liquid transported per unit time, kW;

[0103] t is the pump operation time, h;

[0104] η is the efficiency of a single pump, dimensionless;

[0105] η e is the motor efficiency, dimensionless;

[0106] ρ is the oil density, kg / m 3 ;

[0107] g is the acceleration due to gravity, 9.8N / kg;

[0108] Q is the volume flow rate of oil flowing through the pump, m 3 / s;

[0109] H is the head provided by the pump at the corresponding output. m ;

[0110] The value of the efficiency η of a single pump is related to the actual characteristic curves such as Q-η and QH. These two characteristic curves need to be fitted through the actual operation of the pump.

[0111] Step 2: If multiple pumps are connected in parallel,

[0112]

[0113] Where: t i is the running time of the oil pump, h;

[0114] n is the number of oil delivery pumps, pieces;

[0115] H i The head provided for the i-th external pump, m;

[0116] η i is the efficiency of the i-th external delivery pump, dimensionless;

[0117] η ni is the efficiency of the i-th motor, dimensionless;

[0118] δ is the state of the i-th pump, 0 means the pump is off, 1 means the pump is on;

[0119] The third step is to determine the optimal solution for power costs by determining the start and stop states of different pumps, working time t, and pump characteristic curves under the condition of a certain pipeline output volume.

[0120] Furthermore, the outlet head of the external pump is

[0121]

[0122] After deformation, it can be converted into the pressure of the pump outlet

[0123]

[0124] Where: ρ is the oil density, kg / m 3 ;

[0125] g is the acceleration due to gravity, 9.8N / kg;

[0126] P d It is the pressure of oil when it passes through the outlet of the external pump;

[0127] Z d It is the elevation of the oil product when it passes through the outlet of the external pump;

[0128] C d It is the flow rate of oil passing through the outlet of the external pump;

[0129] P s It is the pressure of oil when it passes through the inlet of the external transfer pump;

[0130] Z s It is the elevation of the oil when it passes through the inlet of the external transfer pump;

[0131] C s It is the flow rate of the oil when it passes through the inlet of the external pump.

[0132] Furthermore, the specific method for obtaining the drug cost in step 3 is as follows:

[0133] S m =YU;

[0134] Y=g(Q)

[0135] Among them: U is the drug price, yuan / kg;

[0136] Y is the amount of drag reducer added, kg;

[0137] The unit price of drag reducer generally remains unchanged, while the amount of drag reducer added Y has a certain correlation with the pipeline pressure drop, that is, the pipeline pressure drop loss; under the condition that the external transmission head remains unchanged, the change of pipeline pressure drop loss will cause the change of external transmission displacement. Therefore, the amount of drag reducer added is correlated with the external transmission displacement. The relationship is determined through field experiments. Once the flow rate is determined, the optimal amount of drag reducer added can be determined based on this flow rate.

[0138] Furthermore, the relationship equation between the pipeline pressure drop loss ΔP and the amount of drag reducer added Y is ΔP=f(Y), which can be determined by field tests and final fitting;

[0139] The relationship between flow rate or flow velocity and pipeline pressure drop can be expressed by the formula

[0140] Sure,

[0141] Therefore, the relationship between the amount of drag reducer added Y and the flow rate or velocity can be determined through field experiments;

[0142] where h f is the head loss along the way,

[0143]

[0144] Where: P m It is the pressure at the outlet of the external transmission pipeline, i.e. the pressure at the end of the external transmission pipeline;

[0145] Z m It is the elevation of the outlet of the external transmission pipeline, i.e. the end of the external transmission pipeline;

[0146] C m is the flow velocity at the outlet of the external transmission pipeline, i.e., the end of the external transmission pipeline;

[0147] P d The pressure at the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump;

[0148] Z d The elevation of the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump;

[0149] C d The flow rate at the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump;

[0150] L is the length of the pipeline, m;

[0151] d is the pipe diameter, m;

[0152] v is the flow rate of the external oil, m / s;

[0153] λ is the resistance coefficient along the path, dimensionless.

[0154] The β and index m can be obtained by consulting relevant manuals on fluid mechanics.

[0155] Furthermore, the method for obtaining the minimum value of the sum of power cost and drug cost in step 4 is to obtain the combination of drag reducer addition amount and power cost under a given flow rate and satisfying constraint conditions.

[0156] Furthermore, the constraints are: first, the head H at the pump outlet must be greater than the head loss h along the pipeline f, the sum of local head loss and elevation difference, so as to meet the normal flow of pipeline fluid and deliver the fluid to the end; secondly, the pressure at the pump outlet must be less than the design pressure or pressure bearing capacity of the pipeline, so as to avoid pipeline rupture and ensure safe operation; thirdly, the daily addition of drag reducer to the external pipeline shall not exceed the target dosage set on site. Find the most economical operation plan after meeting the constraints.

[0157] From the attached Figure 2 It can be seen that as the amount of drag reducer added increases, the external transmission friction decreases, the drag reducer cost also increases, and the power cost provided by the external transmission pump decreases accordingly.

[0158] From the attached Figure 3 It can be seen that the operating cost is the sum of the power cost of the external transmission pump and the drag reducing agent cost. When the external transmission volume of the combined station pipeline is constant, there must be an optimal solution with the lowest operating cost.

[0159] Under the condition that the diameter of the combined station's external transmission pipeline remains unchanged, the present invention controls the dosage of the drag reducer or the pressure of the external transmission pump based on the cost-optimized method, while ensuring the external transmission of crude oil and the safe operation of the pipeline, reducing the amount of drag reducer, reducing operating energy consumption, reducing operating costs, and increasing oil field benefits.

[0160] The present invention combines the pipeline pressure drop (pressure drop loss) with the amount of drag reducer to find the optimal solution, thereby achieving scientific dosage and avoiding waste of agents.

[0161] The present invention combines the outlet pressure of the pump with factors such as the external output volume to find the optimal solution, thereby achieving the purpose of reducing energy consumption and improving pump efficiency.

[0162] After the optimal solution of power cost and chemical addition cost is obtained, the optimal operation cost of the combined station external transmission pipeline is achieved.

[0163] In the later stage of the present invention, the solution model can be embedded in the intelligent control system to realize the intelligent addition and adjustment of the drag reducer dosage according to the different pipeline output volumes.

[0164] In the absence of conflicts, technicians in this field can combine the relevant technical features in the above examples according to actual conditions to achieve corresponding technical effects. The specific combinations are not described here one by one.

[0165] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0166] In addition, the descriptions of "first", "second", etc. in the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0167] The above are only preferred embodiments of the present invention. The present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein. Any simple modification, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for optimizing the increase in transmission of a combined station external transmission pipeline, characterized in that: The steps include: Step 1: Establish a cost objective function F that includes power costs and drug costs min ; Step 2: Calculate the power cost; Step 3: Calculate the cost of medicines; Step 4: Find the minimum value of the sum of power costs and drug costs; Step 5: Pipeline external transport is carried out according to the energy consumption of the external transport pump and the amount of added medicine that minimizes the sum of the power cost and the medicine cost obtained in step 4.

2. A method for optimizing the increase in transmission of a combined station external transmission pipeline according to claim 1, characterized in that: In the step 1, the cost objective function is established as F min , F min =S p +S m Where: S p The power cost is the electricity cost generated by the energy consumption of the external pump; S m The cost of medicines incurred for adding drag reducing agents.

3. A method for optimizing the increase in transmission of a combined station external transmission pipeline according to claim 1 or 2, characterized in that: The specific method for obtaining the power cost in step 2 is as follows: Step 1: Power Cost S p =eW; Where: e is the electricity price, yuan / kW·h; W is the energy consumption of a single pump, kW·h; Energy consumption per pump Where: N e The effective energy obtained by the pump from the liquid transported per unit time, kW; t is the pump operation time, h; η is the efficiency of a single pump, dimensionless; η e is the motor efficiency, dimensionless; ρ is the oil density, kg / m 3 ; g is the acceleration due to gravity, 9.8N / kg; Q is the volume flow rate of oil flowing through the pump, m 3 / s; H is the head provided by the pump at the corresponding output. m ; Step 2: If multiple pumps are connected in parallel, Where: t i is the running time of the oil pump, h; n is the number of oil delivery pumps, pieces; H i The head provided for the i-th external pump, m; η i is the efficiency of the i-th external delivery pump, dimensionless; η ni is the efficiency of the i-th motor, dimensionless; δ is the state of the i-th pump, 0 means the pump is off, 1 means the pump is on; The third step is to determine the optimal solution for power costs by determining the start and stop states of different pumps, working time t, and pump characteristic curves under the condition of a certain pipeline output volume.

4. A method for optimizing the increase in transmission of a combined station external transmission pipeline as claimed in claim 3, characterized in that: The head of the export pump outlet: After deformation, it can be converted into the pressure of the pump outlet Where: ρ is the oil density, kg / m 3 ; g is the acceleration due to gravity, 9.8N / kg; P d It is the pressure of oil when it passes through the outlet of the external pump; Z d It is the elevation of the oil product when it passes through the outlet of the external pump; C d It is the flow rate of oil passing through the outlet of the external pump; P s It is the pressure of oil when it passes through the inlet of the external transfer pump; Z s It is the elevation of the oil when it passes through the inlet of the external transfer pump; C s It is the flow rate of the oil when it passes through the inlet of the external pump.

5. A method for optimizing the increase in transmission of a combined station external transmission pipeline according to claim 1 or 2, characterized in that: The specific method for obtaining the drug cost in step 3 is as follows: S m =YU; Y=g(Q) Among them: U is the drug price, yuan / kg; Y is the amount of drag reducer added, kg; The unit price of the drag reducer is a fixed value, and the amount of drag reducer added Y is related to the pipeline pressure drop, that is, the pipeline pressure drop loss; under the condition that the external transmission head remains unchanged, the change of the pipeline pressure drop loss will cause the change of the external transmission displacement. Therefore, the amount of drag reducer added is related to the external transmission displacement. The mutual relationship is determined through field experiments to determine the flow rate, and the optimal amount of drag reducer added is determined based on this flow rate.

6. A method for optimizing the increase in transmission of a combined station external transmission pipeline according to claim 5, characterized in that: The relationship equation between the pipeline pressure drop loss ΔP and the amount of drag reducer added Y is ΔP=f(Y), which can be determined by field tests and final fitting; The relationship between flow rate or flow velocity and pipeline pressure drop can be expressed by the formula Sure, Therefore, the relationship between the amount of drag reducer added Y and the flow rate or velocity can be determined through field experiments; where h f is the head loss along the way, Where: P m It is the pressure at the outlet of the external transmission pipeline, i.e. the pressure at the end of the external transmission pipeline; Z m It is the elevation of the outlet of the external transmission pipeline, i.e. the end of the external transmission pipeline; C m is the flow velocity at the outlet of the external transmission pipeline, i.e., the end of the external transmission pipeline; P d The pressure at the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump; Z d The elevation of the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump; C d The flow rate at the inlet of the external transmission pipeline, i.e. the outlet of the external transmission pump; L is the length of the pipeline, m; d is the pipe diameter, m; v is the flow rate of the external oil, m / s; λ is the drag coefficient along the path, dimensionless.

7. A method for optimizing the increase in transmission of a combined station external transmission pipeline according to claim 1 or 2, characterized in that: The method for obtaining the minimum value of the sum of the power cost and the drug cost in the step 4 is to obtain the combination of the drag reducer addition amount and the power cost under a given flow rate and satisfying the constraint conditions.

8. A method for optimizing the increase in transmission of a combined station external transmission pipeline according to claim 7, characterized in that: The constraints are: First, the head H at the pump outlet must be greater than the head loss h along the pipeline. f , the sum of local head loss and elevation difference; second, the pressure at the pump outlet must be less than the design pressure or pressure-bearing capacity of the pipeline; third, the daily addition of drag reducer to the external pipeline must not exceed the target dosage set on site.

Images