Water injection system one station frequency regulation and control, regional optimal operation method

Abstract

This invention provides a method for one-station frequency conversion control and regional optimized operation of a water injection system, relating to the technical field of water injection systems for oilfield surface engineering. The method includes the following steps: S1, establishing a central water injection station based on the oilfield topography; S2, establishing multiple branch water injection stations within a radius of no more than 5 kilometers from the central water injection station established in step S1; S3, independently laying pipelines between the central water injection station established in step S1 and the multiple branch water injection stations established in step S2; S4, installing a high-voltage frequency converter on the central water injection pump in the central water injection station established in step S1. By operating one of the water injection pumps with frequency conversion and lowering its frequency, the power frequency pumps of the multiple water injection stations connected to its pipeline network are increased to high-load operation, solving the problems of insufficient energy saving, high energy consumption, and poor continuity in current water injection systems, reducing cost investment, and achieving the goal of controlling the rate of energy consumption growth.

Description

Technical Field

[0001] This invention relates to the field of water injection system technology for oilfield surface engineering, specifically to a method for one-stop frequency conversion control and regional optimized operation of water injection systems. Background Technology

[0002] As oilfield development has entered the ultra-high water-cut stage, the water cut in the oilfield is increasing year by year. To ensure crude oil production targets are met, various production enhancement measures and capacity expansion will be further increased, leading to a continuous increase in electricity consumption for oilfield production. Currently, energy consumption control of water injection systems is mainly analyzed and carried out on a single-station and single-pump basis. On the one hand, "point-to-point" adjustments have limited and unsustainable energy-saving effects; on the other hand, with the increasing application of energy-saving management technologies, the space and potential for energy conservation and consumption reduction are becoming smaller and smaller, making it more difficult to control the rate of energy consumption growth.

[0003] In response to this situation, we conducted research and exploration on the energy-saving mode of "one-stop variable frequency control and regional optimized operation method for water injection system". This mode is designed to achieve regional control of water injection system and water quality pipeline network in oilfield surface engineering, in order to achieve the goal of energy saving and consumption reduction. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a one-stop variable frequency control and regional optimized operation method for water injection systems, which solves the problems of insignificant energy saving, high energy consumption, and poor sustainability in current water injection systems.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for one-stop variable frequency control and regional optimized operation of a water injection system, comprising the following steps: S1. Establish a central water injection station based on the oilfield topography; S2. Based on the central water injection station established in step S1, establish multiple branch water injection stations within a radius of no more than 5 kilometers. S3. Lay independent transmission pipelines between the central water injection station established in step S1 and the multiple branch water injection stations established in step S2. S4. Install one high-voltage frequency converter on the central water injection pump in the central water injection station established in step S1. S5. When the pipeline is in operation, the high-pressure frequency converter of the water injection station in the operation center enables the water injection pumps of its own frequency to operate at a lower frequency, while the power frequency pumps of multiple sub-water injection stations connected to its pipeline network are upgraded to high load operation.

[0006] Preferably, the water injection system is a one-stop variable frequency control and regional optimized operation system, including a central water injection station. The output end of the central water injection station is connected to the input ends of multiple sub-water injection stations through a transmission pipeline, and the input end of the central water injection station is connected to the input end of the ordinary water injection trunk line.

[0007] Preferably, the central water injection station includes a central water injection pump and a high-voltage frequency converter, wherein the central water injection pump is connected to the high-voltage frequency converter.

[0008] Preferably, each of the sub-injection stations includes a power frequency pump, and each power frequency pump is connected to the central injection pump via a delivery pipeline.

[0009] This invention provides a method for one-stop variable frequency control and regional optimized operation of a water injection system. It has the following beneficial effects: This invention achieves energy saving by operating one of the water injection pumps at a lower frequency and increasing the operating frequency of the pumps at multiple water injection stations connected to the pipeline network to a higher load. This solves the problems of insignificant energy saving, high energy consumption, and poor sustainability in current water injection systems, reduces costs, and achieves the goal of controlling the rate of energy consumption growth. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the layout of the water injection network with the same water quality around the No. 1 water injection station, which is the proposed method for one-stop frequency conversion control and regional optimized operation of the water injection system in this invention. Figure 2 This is a schematic diagram of the experimental effect of the regional frequency conversion control of the No. 1 water injection station, which is the proposed method for one-station frequency conversion control and regional optimized operation of the water injection system in this invention. Detailed Implementation

[0011] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1:

[0012] This invention provides a method for one-stop variable frequency control and regional optimized operation of a water injection system, comprising the following steps: S1. Establish a central water injection station based on the oilfield topography; S2. Based on the central water injection station established in step S1, establish multiple branch water injection stations within a radius of no more than 5 kilometers. S3. Lay independent transmission pipelines between the central water injection station established in step S1 and the multiple branch water injection stations established in step S2. S4. Install one high-voltage frequency converter on the central water injection pump in the central water injection station established in step S1. S5. When the pipeline is in operation, the high-pressure frequency converter of the water injection station in the operation center enables the water injection pumps of its own frequency to operate at a lower frequency, while the power frequency pumps of multiple sub-water injection stations connected to its pipeline network are upgraded to high load operation.

[0013] The water injection system is a one-stop variable frequency control and regional optimized operation system, including a central water injection station. The output end of the central water injection station is connected to the input ends of multiple branch water injection stations through delivery pipelines. The input end of the central water injection station is connected to the input end of the ordinary water injection trunk line. The central water injection station includes a central water injection pump and a high-voltage frequency converter, which are connected to the central water injection pump. Each branch water injection station includes a power frequency pump, which is connected to the central water injection pump through delivery pipelines.

[0014] Based on the method in Example 1, the unit consumption and water volume parameters of water injection stations #1, #2, #3, and #4 are shown in Table 1 below:

[0015] Table 1. Electricity Consumption Statistics of Water Injection Station No. 1 and Surrounding Water Injection Stations Based on the method in Example 1, the pump pressure, pump-pipe pressure differential, and pipe pressure parameters of injection stations #1, #2, #3, and #4 are shown in Table 2 below:

[0016] Table 2. Statistical Table of Pressure Data Before and After Frequency Conversion Regulation at Water Injection Station #1 Conclusion: As shown in Table 1-2, with the total water volume remaining basically unchanged, the water volume at injection station #1 decreased, while the water volume at injection stations #2, #3, and #4 increased. The pipe pressure in the central area decreased by 0.7 MPa. Simultaneously, the unit consumption of all four injection stations showed a decreasing trend, with the system unit consumption decreasing from 6.07 kW·h / m³. 3 Reduced to 5.90 kW.h / m 3 It decreased by 0.17 kWh / m 3 The decrease was 2.8%.

[0017] Based on the water saving rate, the system's power saving = difference in unit consumption × water saving rate. The daily power consumption decreased from 21.92×104 kWh to 21.29×104 kWh, a decrease of 0.63×104 kWh. Considering 300 days of operation per year, the annual power saving is 189×104 kWh. Example 2:

[0018] According to Example 1, water injection stations #5, #6, and #7 were constructed. Pump #3 of water injection station #5 was equipped with a high-pressure variable frequency drive (VFD) device, serving as the central station. Surrounding stations #6 and #7 belong to the same deep water and water quality pipeline network, allowing for energy-saving optimization adjustments through "one-station VFD control and regional optimized operation," as shown in Table 3 below.

[0019] Table 3. Operation status of the pipeline network in the area corresponding to Water Injection Station No. 5 and Water Injection Pump No. 3. Conclusion: As shown in Table 3, the unit consumption of the regional water injection system decreased by 0.17 kW·h / m³ after adjustment. Calculated based on 300 days of operation per year for the variable frequency system, the annual electricity saving is 126 × 10⁴ kW·h while ensuring that the total regional water volume remains unchanged. Example 3:

[0020] According to Example 1, water injection stations #8, #9, and #10 are laid. Water injection pump #3 of station #8 is equipped with a high-pressure variable frequency drive (VFD) and serves as the central station. Stations #9 and #10, located nearby, belong to the same deep water injection network. Energy-saving optimization adjustments can be made through "one-station VFD control and regional optimized operation," as shown in Table 4 below.

[0021] Table 4. Operation status of the pipeline network in the area corresponding to Water Injection Station No. 8 and Water Injection Pump No. 3. Conclusion: As shown in Table 4, the unit consumption of the regional water injection system decreased by 0.17 kW·h / m³ after adjustment. Calculated based on 300 days of operation per year for the variable frequency drive, the annual electricity saving is 134 × 10⁴ kW·h while ensuring the total regional water volume remains unchanged. Example 4:

[0022] According to Example 1, water injection stations #8, #9, and #10 are laid. Water injection pump #3 of station #8 is equipped with a high-pressure variable frequency drive (VFD) and serves as the central station. Stations #9 and #10, located nearby, belong to the same deep water injection network. Energy-saving optimization adjustments can be made through "one-station VFD control and regional optimized operation," as shown in Table 5 below.

[0023] Table 5. Operation status of the pipeline network in the area corresponding to Water Injection Station No. 11 and Water Injection Pump No. 2. Conclusion: As shown in Table 5, the unit consumption of the regional water injection system decreased by 0.17 kW·h / m³ after adjustment. Calculated based on 300 days of operation per year for the frequency converter, the annual electricity saving is 134 × 10⁴ kW·h while ensuring that the total regional water volume remains unchanged.

[0024] In summary, by operating one of the water injection pumps using frequency conversion and lowering its frequency, and by increasing the operating frequency of the pumps at multiple water injection stations connected to its pipeline network to high load, energy conservation is achieved while maintaining the total water volume. This solves the problems of insignificant energy-saving effects, high energy consumption, and poor sustainability in the current water injection system, reduces costs, and achieves the goal of controlling the rate of energy consumption growth.

[0025] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for one-stop variable frequency control and regional optimized operation of a water injection system, characterized by: Includes the following steps: S1. Establish a central water injection station based on the oilfield topography; S2. Based on the central water injection station established in step S1, establish multiple branch water injection stations within a radius of no more than 5 kilometers. S3. Lay independent transmission pipelines between the central water injection station established in step S1 and the multiple branch water injection stations established in step S2. S4. Install one high-voltage frequency converter on the central water injection pump in the central water injection station established in step S1. S5. When the pipeline is in operation, the high-pressure frequency converter of the water injection station in the operation center enables the water injection pumps of its own frequency to operate at a lower frequency, while the power frequency pumps of multiple sub-water injection stations connected to its pipeline network are upgraded to high load operation.

2. A water injection system with one-stop variable frequency control and regional optimized operation, characterized in that: The method for one-stop frequency conversion control and regional optimized operation of a water injection system according to claim 1 includes a central water injection station, wherein the output end of the central water injection station is connected to the input ends of multiple sub-water injection stations through a transmission pipeline, and the input end of the central water injection station is connected to the input end of a general water injection trunk line.

3. The water injection system with one-station frequency conversion control and regional optimized operation as described in claim 2, characterized in that: The central water injection station includes a central water injection pump and a high-voltage frequency converter, and the central water injection pump is connected to the high-voltage frequency converter.

4. The water injection system with one-station frequency conversion control and regional optimized operation as described in claim 2, characterized in that: Each of the sub-injection stations includes a power frequency pump, and each power frequency pump is connected to the central injection pump via a delivery pipeline.

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