On-line monitoring device for water quality of oilfield reinjection water
By designing an online monitoring device for water quality in oil field back injection, using multiple measurement tanks and sensors to detect and recover water quality that does not meet the standards, the problem of water return injection pollution in oil field is solved, water quality monitoring and cleaning liquid recovery is realized, and the safety and equipment of the water system are ensured. Maintenance.
Patent Information
- Application Number
- CN202323439593.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-15
- Publication Date
- 2025-01-07
- Estimated Expiration
- 2033-12-15
AI Technical Summary
There is water quality pollution problem in the oil field return water injection, resulting in the production water treatment not meeting the standards, which may cause pollution to the surface water system or groundwater system and break the water system balance.
Design an online monitoring device for water quality in oil field return injection, including a target sample injection unit, a measurement unit, a cleaning unit and a liquid return unit. The water quality detection and cleaning liquid recovery are realized through at least two measuring tanks and sample liquid measurement sensors to avoid Water quality meets standards is discharged at will.
It realizes online monitoring of oil field return water and cleaning liquid recovery, prevents water quality pollution, ensures timely maintenance of equipment, and provides a basis for safe use of oil field return water.
Smart Images
Figure CN222318920U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of on-line monitoring of oilfield reinjection water quality, in particular to an on-line monitoring device for oilfield reinjection water quality. Background Art
[0002] As the oil field is produced and developed, the reservoir pressure will gradually decrease. In order to solve this problem, the reservoir pressure is increased by injecting water into the oil layer to maintain the balance of the reservoir pressure. In this project, produced water will be generated. The produced water is generally discharged or reinjected. Since the produced water contains a certain amount of suspended matter such as oil and sulfide, the produced water needs to be treated regardless of whether it is discharged or reinjected. If the produced water quality treatment does not meet the standards, it will pollute the surface water system or the groundwater system, disrupt the balance of the water system itself, and cause water pollution incidents. Summary of the invention
[0003] In order to solve the problems existing in the prior art, the purpose of the utility model is to provide an online monitoring device for the water quality of oilfield reinjection water. The utility model can perform online monitoring of the water quality of oilfield reinjection water. According to the monitoring results of the utility model, it can provide a basis for the discharge or reinjection of oilfield reinjection water using the utility model, which is conducive to the safe use of oilfield reinjection water.
[0004] The technical solution adopted by the utility model is as follows:
[0005] An oilfield reinjection water quality online monitoring device comprises a target sample liquid injection unit, a target sample liquid measurement unit, a target sample liquid measurement pool cleaning unit and a target sample liquid return unit, wherein the target sample liquid measurement unit comprises at least two measurement pools, each measurement pool is provided with a sample liquid measurement sensor, a sample liquid inlet and a sample liquid outlet are provided at the bottom of the measurement pool, and a sample liquid overflow port is provided at the top of the measurement pool;
[0006] All measuring cells are connected in series in sequence, and the series connection method is as follows: the sample liquid overflow port of the previous measuring cell is connected to the sample liquid inlet port of the next measuring cell through a pipeline; the sample liquid inlet port of the first measuring cell is connected to the outlet port of the target sample liquid injection unit, and the outlet port of the target sample liquid injection unit is provided with a first control valve; the sample liquid overflow port of the last measuring cell is connected to the target sample liquid return unit, and the sample liquid outlets of all measuring cells are connected to a collection pipe through a pipeline, and the collection pipe is connected to the target sample liquid return unit, and a second control valve is provided on the collection pipe;
[0007] The outlet of the target sample liquid measuring pool cleaning unit is connected to the sample liquid inlet of the first measuring pool, and the outlet of the target sample liquid measuring pool cleaning unit is provided with a third control valve.
[0008] Preferably, the target sample liquid injection unit includes a first manual ball valve, an explosion-proof flowmeter, a first explosion-proof electric ball valve, a first explosion-proof solenoid valve and a sample liquid storage box. The first manual ball valve, the explosion-proof flowmeter, the first explosion-proof electric ball valve, the first explosion-proof solenoid valve and the sample liquid storage box are connected in series in sequence through pipelines. An outlet is provided at the bottom of the sample liquid storage box, which serves as the outlet of the entire target sample liquid injection unit. The outlet of the sample liquid storage box is connected to the sample liquid inlet of the first measuring cell through a pipeline, and the first control valve is provided on the pipeline.
[0009] Preferably, a liquid level detection port is further provided at the upper portion of the sample liquid storage box, and the liquid level detection port also serves as an overflow port of the sample liquid storage box. A liquid discharge pipe is connected to the liquid level detection port, and an explosion-proof photoelectric liquid level switch is provided on the liquid discharge pipe, and a manual ball valve is provided at the outlet;
[0010] The drain pipe is also connected to the target sample liquid return unit through the first pipeline. The connection point between the drain pipe and the pipeline is located downstream of the explosion-proof photoelectric liquid level switch. The drain pipe and the first pipeline are connected through a tee.
[0011] Preferably, the sample liquid overflow port of the last measuring cell is connected to the first pipeline through a tee.
[0012] Preferably, the target sample liquid measuring pool cleaning unit includes a cleaning box and a cleaning pump, the inlet of the cleaning pump is connected to the cleaning box, the outlet of the cleaning pump is connected to the sample liquid inlet of the first measuring pool through a cleaning pipe, and the outlet of the cleaning pump is provided with the third control valve.
[0013] Preferably, the outlet of the target sample solution injection unit, the sample solution inlet of the first measuring cell and the cleaning tube are connected through a tee.
[0014] Preferably, a drain valve is also provided at the bottom of the cleaning box.
[0015] Preferably, the target sample liquid return unit comprises a liquid return storage box, an explosion-proof water pump, a third explosion-proof electric ball valve, a one-way valve, and a fourth manual ball valve, and the bottom of the liquid return storage box, the explosion-proof water pump, the third explosion-proof electric ball valve, the one-way valve, and the fourth manual ball valve are connected in series in sequence through a pipeline;
[0016] The sample liquid overflow port and the collecting pipe of the last measuring cell are connected to the return liquid storage tank.
[0017] Preferably, an explosion-proof radio frequency liquid level meter is provided on the return liquid storage box.
[0018] Preferably, the sample liquid outlet of the measuring cell is not higher than the sample liquid inlet, and the sample liquid overflow port of the measuring cell is located at one side of the sample liquid outlet, which helps the sample liquid or cleaning liquid in the measuring cell to flow out by itself.
[0019] Preferably, the first control valve adopts the second explosion-proof electric ball valve, the second control valve adopts the third explosion-proof solenoid valve, and the third control valve adopts the second explosion-proof solenoid valve.
[0020] The utility model has the following beneficial effects:
[0021] The utility model of the online monitoring device for the quality of oilfield reinjection water can obtain the oilfield reinjection water and provide the oilfield reinjection water to the target sample liquid measurement unit. The target sample liquid measurement unit detects the objects to be detected (such as oil in water, suspended matter, etc.) in the oilfield reinjection water by setting a sample liquid measurement sensor in the measurement pool. Since each detection requires at least two indicators of the objects to be detected, the utility model sets at least two measurement pools, and different sample liquid measurement sensors can be set in each measurement pool, so as to realize the detection of different objects to be detected in the oilfield reinjection water. The sample liquid inlet and the sample liquid overflow port of the measurement pool are finally connected to the target sample liquid return unit, so that the oilfield reinjection water that has been detected can be recycled through the target sample liquid return unit, so as to avoid the oilfield reinjection water that does not meet the water quality standards from being discharged at will and polluting other normal water bodies. The utility model is also provided with a target sample liquid measuring pool cleaning unit. After completing the detection task, the target sample liquid measuring pool cleaning unit can be used to clean the inside of the measuring pool. Similarly, the cleaning water can be finally connected to the target sample liquid return unit through the sample liquid inlet and the sample liquid overflow port of the measuring pool. In this way, the cleaning water can be recovered and stored through the target sample liquid return unit, and the cleaning water can be discharged at will to pollute the environment. It can be seen that the utility model can realize the online monitoring of the water quality of oilfield reinjection water, and at the same time can avoid the random discharge of the detection sample liquid and the cleaning liquid to pollute the environment. At the same time, the measuring pool can also be cleaned online, so that the equipment can be cleaned and maintained in a timely and effective manner. In addition, according to the monitoring results of the utility model, it can provide a basis for the external discharge or reinjection of the oilfield reinjection water using the utility model, which is conducive to the safe use of the oilfield reinjection water. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a structural schematic diagram of an online monitoring device for oilfield reinjection water quality in an embodiment of the utility model.
[0023] Figure 2 It is a structural schematic diagram of a target sample liquid measuring unit in an embodiment of the utility model.
[0024] In the figure, 1-first manual ball valve, 2-explosion-proof flowmeter, 3-first explosion-proof electric ball valve, 4-first explosion-proof solenoid valve, 5-sample liquid storage box, 6-explosion-proof photoelectric liquid level switch, 7-third manual ball valve, 8-second explosion-proof electric ball valve, 9-second manual ball valve, 10-cleaning box, 11-second explosion-proof solenoid valve, 12-1-first stainless steel three-way connector, 12-2-second stainless steel three-way connector, 12-3-third stainless steel three-way connector, 12-4-fourth stainless steel three-way connector, 13-first measuring cell, 14-second measuring Measuring pool, 15-first sample liquid measuring sensor, 16-second sample liquid measuring sensor, 17-third explosion-proof solenoid valve, 18-return liquid storage box, 19-explosion-proof radio frequency level meter, 20-explosion-proof water pump, 21-third explosion-proof electric ball valve, 22-check valve, 23-fourth manual ball valve, 24-sample liquid inlet, 25-overflow port, 26-cleaning liquid inlet, 27-outlet, 28-drain pipe, 29-first pipeline, 30-sample liquid inlet, 31-sample liquid outlet, 32-sample liquid overflow port, 33-cleaning pipe, 34-collecting pipe. DETAILED DESCRIPTION
[0025] The utility model is further described below in conjunction with the accompanying drawings and embodiments.
[0026] Reference Figure 1 and Figure 2 The utility model discloses an online monitoring device for the water quality of oilfield reinjection water, comprising a target sample liquid injection unit, a target sample liquid measurement unit, a target sample liquid measurement pool cleaning unit and a target sample liquid return unit, wherein the target sample liquid measurement unit comprises at least two measurement pools, each of which is provided with a sample liquid measurement sensor, a sample liquid inlet and a sample liquid outlet are provided at the bottom of the measurement pool, and a sample liquid overflow port is provided at the top of the measurement pool; all the measurement pools are connected in series in sequence, and the series connection manner is as follows: the sample liquid overflow port of the previous measurement pool is connected to the sample liquid inlet of the next measurement pool through a pipeline; the sample liquid inlet of the first measurement pool is connected to the outlet of the target sample liquid injection unit, the outlet of the target sample liquid injection unit is provided with a first control valve, the sample liquid overflow port of the last measurement pool is connected to the target sample liquid return unit, the sample liquid outlets of all the measurement pools are connected to a collection pipe through a pipeline, the collection pipe is connected to the target sample liquid return unit, and a second control valve is provided on the collection pipe; the outlet of the target sample liquid measurement pool cleaning unit is connected to the sample liquid inlet of the first measurement pool, and the outlet of the target sample liquid measurement pool cleaning unit is provided with a third control valve.
[0027] The working principle of the above-mentioned oilfield reinjection water quality online monitoring device of the utility model is as follows:
[0028] When testing the quality of oilfield reinjection water, the first control valve is opened, the second control valve and the third control valve are closed (and are in a normally closed state), and the oilfield reinjection water to be tested (referred to as sample liquid for short) is injected into the target sample liquid measuring unit through the target sample liquid injection unit. When the sample liquid passes through the measuring cells connected in series, when the sample liquid in the first measuring cell is full, the sample liquid in the first measuring cell overflows to the second measuring cell through the sample liquid overflow port of the measuring cell. When the second measuring cell is full, the sample liquid in the second measuring cell overflows to the next measuring cell through the sample liquid overflow port of the measuring cell, and so on, until the last measuring cell is full of sample liquid, at which time the first control valve is closed; the sample liquid measuring sensor on each measuring cell detects the sample liquid in the measuring cell to obtain the content of the corresponding detection object. After the detection of the detection object of the sample liquid in the measuring cell is completed, the second control valve is opened, and the sample liquid in all measuring cells flows into the target sample liquid return unit through the sample liquid outlet at the bottom.
[0029] When the measuring pool needs to be cleaned, the third control valve is opened, and the first control valve and the second control valve are closed. The cleaning process is similar to the measuring process. At this time, the first control valve is in a normally closed state. The cleaning liquid is injected into the target sample liquid measuring unit through the target sample liquid measuring pool cleaning unit. When the cleaning liquid passes through the measuring pools connected in series, when the cleaning liquid in the first measuring pool is full, the cleaning liquid in the first measuring pool overflows to the second measuring pool through the sample liquid overflow port of the measuring pool. After the second measuring pool is full, the cleaning liquid in the second measuring pool overflows to the next measuring pool through the sample liquid overflow port of the measuring pool, and so on, until the last measuring pool is full. The cleaning liquid is continuously injected into the target sample liquid measuring unit through the target sample liquid measuring pool cleaning unit, so that each measuring pool is in an overflow state until all the measuring pools are rinsed clean. At this time, the cleaning effect can be observed through the detection result of the sample liquid measuring sensor on the measuring pool, or the water quality of the cleaning liquid can be detected to determine whether it is cleaned; when all the measuring pools are cleaned, the third control valve is closed and the second control valve is opened, and the cleaning liquid in all the measuring pools flows into the target sample liquid return unit through the sample liquid outlet at the bottom. During the flow process, the pipeline where the second control valve is located is rinsed, thereby ensuring that all pipelines are cleaned.
[0030] Example
[0031] The on-line monitoring device for oilfield reinjection water quality in this embodiment refers to Figure 1 and Figure 2, including a sample liquid storage box 5, a first explosion-proof electric ball valve 3, a first explosion-proof solenoid valve 4, an explosion-proof photoelectric liquid level switch 6, a cleaning box 10, a second explosion-proof solenoid valve 11, a second explosion-proof electric ball valve 8, a first measuring pool 13, a second measuring pool 14, a third explosion-proof solenoid valve 17, a return liquid storage box 18, an explosion-proof radio frequency liquid level meter 19, an explosion-proof water pump 20, a third explosion-proof electric ball valve 21 and a one-way valve 22. The target sample liquid injection unit includes a first manual ball valve 1, an explosion-proof flowmeter 2, a first explosion-proof electric ball valve 3, a first explosion-proof solenoid valve 4 and a sample liquid storage box 5. The first manual ball valve 1, the explosion-proof flowmeter 2, the first explosion-proof electric ball valve 3, the first explosion-proof solenoid valve 4 and the sample liquid storage box 5 are connected in series in sequence through pipelines. The sample liquid storage box 5 and the explosion-proof photoelectric liquid level switch 6 are connected to the third stainless steel three-way joint 12-3 and the third manual ball valve 7 through a drain pipe 28. The drain pipe 28 is connected to the first pipeline 29 through the third stainless steel three-way joint 12-3, and the outlet end of the first pipeline 29 is connected to the return liquid storage box 18.
[0032] The second manual ball valve 9 in the target sample liquid measuring pool cleaning unit is connected to the cleaning box 10 through a pipeline, the outlet of the cleaning box 10 is connected to the cleaning pipe 33, and the second explosion-proof solenoid valve 11 is arranged on the cleaning pipe 33. The cleaning pipe 33 and the outlet of the sample liquid storage box 5 are connected to the sample liquid inlet of the first measuring pool 13 in the target sample liquid measuring unit through the first stainless steel three-way joint 12-1, and the second explosion-proof electric ball valve 8 is arranged at the outlet of the sample liquid storage box 5. This embodiment is described by taking two measuring pools as an example, the two measuring pools are respectively the first measuring pool 13 and the second measuring pool 14, the outlets of the first measuring pool 13 and the second measuring pool 14 are connected to a collection pipe 34 through a pipeline through a second stainless steel three-way joint 12-2, the collection pipe 34 is provided with a third explosion-proof electromagnetic valve 17, the outlet of the collection pipe 34 is connected to the return liquid storage box 18, the sample liquid overflow port of the second measuring pool 14 is connected to the first pipeline 29 through a fourth stainless steel three-way joint 12-4, the first sample liquid measurement sensor 15 is installed inside the first measuring pool 13, the second sample liquid measurement sensor 16 is installed inside the second measuring pool 14, and the explosion-proof radio frequency level meter 19 is installed inside the return liquid storage box 18. The target sample liquid return unit is connected in series in sequence through the return liquid storage box 18, the explosion-proof water pump 20, the third explosion-proof electric ball valve 21, the one-way valve 22, and the fourth manual ball valve 23 through pipelines.
[0033] The target sample liquid injection unit controls the sample liquid injection flow rate through the first explosion-proof electric ball valve 3 and the explosion-proof flowmeter 2. A certain flow rate of target sample liquid enters from the bottom of the sample liquid storage box 5 through a pipeline with an inner diameter of 10-12mm and a wall thickness of 1.5-2.0mm. The flow rate is controlled to ensure that no excess bubbles appear when the target sample liquid enters the sample liquid storage box 5. The first explosion-proof solenoid valve 3 controls the opening and closing of the sample liquid injection. The target sample liquid injection unit samples the target sample liquid and stores it in the sample liquid storage box 5 for storage and retention to prevent the target sample liquid from filling the sample liquid storage box 5. The sample liquid storage box 5 and the explosion-proof photoelectric liquid level switch 6 are connected to the third stainless steel three-way connector 12-3 and the third manual ball valve 7 through a pipeline with an inner diameter of 14-16mm and a wall thickness of 1.5-2.0mm to form a sample liquid overflow port. The sample liquid overflow signal feedback is detected by the explosion-proof photoelectric liquid level switch 6, and the first explosion-proof solenoid valve 4 is closed, and the sample liquid injection stops.
[0034] After the target sample liquid is injected into the target sample liquid measuring unit, the second explosion-proof electric ball valve 8 is opened, and the sample liquid enters the target sample liquid measuring unit through a pipeline with an inner diameter of 10-12 mm and a wall thickness of 1.5-2.0 mm. The first measuring pool 13 and the second measuring pool 14 in the target sample liquid measuring unit are connected through a pipeline with an inner diameter of 10-12mm and a wall thickness of 1.5-2.0mm. The first sample liquid measuring sensor 15 is installed inside the first measuring pool 13, and the second sample liquid measuring sensor 16 is installed inside the second measuring pool 14. When the sample liquid fills the first measuring pool 13 and the second measuring pool 14, the second measuring pool 14 is connected to the return liquid storage tank 18 through a pipeline with an inner diameter of 14-16mm and a wall thickness of 1.5-2.0mm and the fourth stainless steel three-way joint 12-4 and is discharged into the return liquid storage tank 18 for storage. The first measuring pool 13 and the second measuring pool 14 are connected to the third explosion-proof solenoid valve 17 and the return liquid storage tank 18 through a pipeline and the second stainless steel three-way joint 12-2. The explosion-proof radio frequency liquid level meter 19 is installed inside the return liquid storage tank 18, and the third explosion-proof solenoid valve 17 is in a closed state.
[0035] The target sample liquid measuring pool cleaning unit is connected to the first measuring pool 13 and the second measuring pool 14 in the target sample liquid measuring unit through the second manual ball valve 9, the cleaning box 10, the second explosion-proof solenoid valve 11 through the inner diameter 10-12mm, wall thickness 1.5-2.0mm pipeline and the first stainless steel three-way joint 12-1. The cleaning liquid or calibration liquid enters the target sample liquid measuring pool cleaning unit from the cleaning liquid inlet through the second manual ball valve 9 to clean and calibrate the inside of the first measuring pool 13 and the second measuring pool 14 and the first sample liquid measurement sensor 15 and the second sample liquid measurement sensor 16. After the cleaning is completed, the third explosion-proof solenoid valve 17 is opened, and the cleaning liquid is discharged from the bottom of the first measuring pool 13 and the second measuring pool 14 into the return liquid storage box 18 for storage. The target sample liquid return unit is connected in series in sequence through the return liquid storage box 18, the explosion-proof water pump 20, the third explosion-proof electric ball valve 21, the one-way valve 22, and the fourth manual ball valve 27 through a pipeline with an inner diameter of 14-16mm and a wall thickness of 1.5-2.0mm. The explosion-proof radio frequency liquid level meter 19 detects the high point signal of the liquid level, opens the third explosion-proof electric ball valve 21 and the explosion-proof water pump 20 to discharge the crude liquid stored in the return liquid storage box 18 from the outlet 27 through the fourth manual ball valve 23, and the one-way valve 22 prevents the discharged liquid from flowing back.
[0036] The target sample liquid injection unit uses an explosion-proof flowmeter 2 and a first explosion-proof electric ball valve 3 to control the target sample liquid entry flow rate within a preset range. The sample liquid is stored in a sample liquid storage box 5 so that the target sample liquid enters the measuring pool without generating bubbles. The opening and closing of the first explosion-proof solenoid valve 4 is controlled by the signal feedback of the explosion-proof photoelectric liquid level switch 6 to control the opening and closing of the sample liquid injection.
[0037] The target sample liquid injection unit, target sample liquid cleaning unit and target sample liquid measurement unit use pipelines with an inner diameter of 10-12mm and a wall thickness of 1.5-2.0mm. The target sample liquid return unit uses pipelines with an inner diameter of 14-16mm and a wall thickness of 1.5-2.0mm. The injection inner diameter in the pipeline is smaller than the outlet inner diameter, and the injection air resistance changes from large to small, ensuring the flow pressure balance during the injection process. The sample liquid flows more stably with less fluctuation, and no bubbles are generated to affect the measurement.
[0038] In the target sample liquid measuring pool cleaning unit, the cleaning liquid or calibration liquid enters the target sample liquid measuring pool cleaning unit from the cleaning liquid inlet through the second manual ball valve 9 to clean and calibrate the inside of the first measuring pool 13 and the second measuring pool 14 and the first sample liquid measuring sensor 15 and the second sample liquid measuring sensor 16. During the cleaning process, the oily impurities, suspended matter, etc. in the first measuring pool 13 and the second measuring pool 14 are precipitated or suspended in the water and are flushed with the cleaning liquid and driven by the water flow to be discharged from the bottom of the first measuring pool 13 and the second measuring pool 14 into the return liquid storage box 18 for storage.
[0039] The explosion-proof radio frequency level meter 19 of the target sample liquid return unit is installed inside the return liquid storage box 18. The explosion-proof radio frequency level meter 19 detects the high point signal of the return liquid level, opens the third explosion-proof electric ball valve 21 and the explosion-proof water pump 20 to discharge the liquid from the discharge port, and the one-way valve 22 prevents the discharge liquid from flowing back.
[0040] The above-mentioned on-line monitoring device for oilfield reinjection water quality of the utility model can make the inlet inner diameter of the target sample liquid pipeline smaller than the outlet inner diameter during the on-line monitoring and measurement of the oilfield reinjection water quality, and the inlet air resistance changes from large to small, thereby ensuring the flow pressure balance during the injection process, the sample liquid flows more stably, the fluctuation is small, no bubbles are generated, and the cleaning is convenient to ensure that the measuring sensor is not affected by pollutants, thereby ensuring that the measurement result is more accurate.
Claims
1. An online monitoring device for oilfield reinjection water quality, characterized in that: The target sample liquid injection unit includes a target sample liquid measurement unit, a target sample liquid measurement pool cleaning unit and a target sample liquid return unit. The target sample liquid measurement unit includes at least two measurement pools, each measurement pool is provided with a sample liquid measurement sensor, the bottom of the measurement pool is provided with a sample liquid inlet and a sample liquid outlet, and the top of the measurement pool is provided with a sample liquid overflow port; All measuring cells are connected in series in sequence, and the series connection method is as follows: the sample liquid overflow port of the previous measuring cell is connected to the sample liquid inlet port of the next measuring cell through a pipeline; the sample liquid inlet port of the first measuring cell is connected to the outlet port of the target sample liquid injection unit, and the outlet port of the target sample liquid injection unit is provided with a first control valve; the sample liquid overflow port of the last measuring cell is connected to the target sample liquid return unit, and the sample liquid outlets of all measuring cells are connected to a collection pipe through a pipeline, and the collection pipe is connected to the target sample liquid return unit, and a second control valve is provided on the collection pipe; The outlet of the target sample liquid measuring pool cleaning unit is connected to the sample liquid inlet of the first measuring pool, and the outlet of the target sample liquid measuring pool cleaning unit is provided with a third control valve.
2. The on-line monitoring device for oilfield reinjection water quality according to claim 1 is characterized in that: The target sample liquid injection unit comprises a first manual ball valve (1), an explosion-proof flow meter (2), a first explosion-proof electric ball valve (3), a first explosion-proof solenoid valve (4) and a sample liquid storage box (5); the first manual ball valve (1), the explosion-proof flow meter (2), the first explosion-proof electric ball valve (3), the first explosion-proof solenoid valve (4) and the sample liquid storage box (5) are sequentially connected in series through a pipeline; an outlet is provided at the bottom of the sample liquid storage box (5), and the outlet serves as the outlet of the entire target sample liquid injection unit; the outlet of the sample liquid storage box (5) is connected to the sample liquid inlet of the first measuring cell through a pipeline, and the first control valve is provided on the pipeline.
3. The on-line monitoring device for oilfield reinjection water quality according to claim 2 is characterized in that: The upper part of the sample liquid storage box (5) is also provided with a liquid level detection port, which also serves as an overflow port of the sample liquid storage box (5). A liquid discharge pipe is connected to the liquid level detection port, and an explosion-proof photoelectric liquid level switch (6) is provided on the liquid discharge pipe, and a manual ball valve is provided at the outlet. The drain pipe is also connected to the target sample liquid return unit through a first pipeline. The connection point between the drain pipe and the pipeline is located downstream of the explosion-proof photoelectric liquid level switch (6). The drain pipe and the first pipeline are connected through a tee.
4. The on-line monitoring device for oilfield reinjection water quality according to claim 3 is characterized in that: The sample liquid overflow port of the last measuring cell is connected to the first pipeline through a tee.
5. The on-line monitoring device for oilfield reinjection water quality according to claim 1 is characterized in that: The target sample liquid measuring pool cleaning unit comprises a cleaning box (10) and a cleaning pump, wherein the inlet of the cleaning pump is connected to the cleaning box (10), the outlet of the cleaning pump is connected to the sample liquid inlet of the first measuring pool via a cleaning pipe, and the outlet of the cleaning pump is provided with the third control valve.
6. The on-line monitoring device for oilfield reinjection water quality according to claim 5 is characterized in that: The outlet of the target sample solution injection unit, the sample solution inlet of the first measuring cell and the cleaning tube are connected through a three-way connection.
7. The on-line monitoring device for oilfield reinjection water quality according to claim 5 is characterized in that: The bottom of the cleaning box (10) is also provided with a drain valve.
8. The on-line monitoring device for oilfield reinjection water quality according to claim 1 is characterized in that: The target sample liquid return unit comprises a liquid return storage box (18), an explosion-proof water pump (20), a third explosion-proof electric ball valve (21), a check valve (22), and a fourth manual ball valve (23); the bottom of the liquid return storage box (18), the explosion-proof water pump (20), the third explosion-proof electric ball valve (21), the check valve (22), and the fourth manual ball valve (23) are sequentially connected in series through a pipeline; The sample liquid overflow port and the collecting pipe of the last measuring cell are connected to the return liquid storage box (18).
9. The on-line monitoring device for oilfield reinjection water quality according to claim 1 is characterized in that: An explosion-proof radio frequency liquid level meter (19) is provided on the return liquid storage box (18).
10. The on-line monitoring device for oilfield reinjection water quality according to claim 1, characterized in that: The sample liquid outlet of the measuring cell is not higher than the sample liquid inlet, and the sample liquid overflow port of the measuring cell is located at one side of the sample liquid outlet.