Oil field fracturing waste liquid desanding device

Abstract

The utility model discloses an oil field fracturing waste liquid desanding device, which relates to the technical field of oil field exploitation and is characterized in that a first cyclone desander is provided with a first liquid inlet, a first sand outlet and a first liquid outlet; the second cyclone desander is provided with a second liquid inlet, a second sand outlet and a second liquid outlet; the separating, filtering and settling tank is provided with a settling tank liquid inlet pipe, a settling tank first sand outlet, a settling tank second sand outlet and a settling tank liquid outlet pipe; the filter screen type filter is provided with a filter liquid inlet, a filter sand outlet and a filter liquid outlet; the water purification tank is provided with a water purification tank liquid inlet; and the sand-water separation tank is provided with a separation tank sand inlet, a separation tank sand outlet and a separation tank liquid outlet. By arranging the sand-water separation tank, accumulated sand discharged from each sand outlet is dehydrated, and separated clear water flows back to the first liquid inlet for circulation, so that the sand removal recovery rate and the clear water utilization rate of the oilfield fracturing waste liquid are improved.

Description

Technical Field

[0001] This application relates to the field of oilfield development technology, and in particular to a sand removal device for oilfield fracturing waste fluid. Background Technology

[0002] The waste fluid generated from fracturing operations in oilfields contains a large amount of sand and chemical additives. Direct discharge or reinjection of this fluid can lead to formation blockage, soil pollution, and water body damage, seriously threatening ecological and environmental safety. Sand removal is a prerequisite for the reuse of oilfield fracturing waste fluid; therefore, research on sand removal devices for oilfield fracturing waste fluid is necessary.

[0003] In the prior art, Chinese patent CN104368188A discloses a desandering process for oilfield fracturing flowback fluid. After being treated by a cyclone desandering device, the waste liquid is connected to a depressurization and degassing device for gas-liquid separation and filtration sedimentation. Then, it is directly pumped into a primary filtration device and a wastewater tank by a primary water pump for static sedimentation. Finally, it is directly pumped into a secondary filtration device by a secondary water pump for treatment and finally introduced into a clean water tank.

[0004] However, the aforementioned existing technologies do not consider the treatment of accumulated sand discharged from each sand outlet, resulting in low sand removal recovery rate and clean water utilization rate of oilfield fracturing waste fluid. Utility Model Content

[0005] This application provides a sand removal device for oilfield fracturing waste fluid, which solves the problems of low sand removal recovery rate and clean water utilization rate of oilfield fracturing waste fluid in the prior art.

[0006] On the one hand, this application provides a sand removal device for oilfield fracturing wastewater, including: a first cyclone desander, a second cyclone desander, a separation filtration sedimentation tank, a screen filter, a clean water tank, and a sand-water separation tank.

[0007] The first cyclone sand separator is provided with a first liquid inlet, a first sand outlet, and a first liquid outlet.

[0008] The second cyclone sand separator is provided with a second liquid inlet, a second sand outlet, and a second liquid outlet.

[0009] The separation and filtration sedimentation tank is equipped with a sedimentation tank inlet pipe, a sedimentation tank first sand outlet, a sedimentation tank second sand outlet, and a sedimentation tank outlet pipe.

[0010] The filter screen is equipped with a filter inlet, a filter sand outlet, and a filter outlet.

[0011] The water purification tank is equipped with a water purification tank inlet.

[0012] The sand-water separator is equipped with a sand inlet, a sand outlet, and a liquid outlet.

[0013] The first inlet is used to input oilfield fracturing waste fluid. The first outlet is connected to the second inlet. The second outlet is connected to the sedimentation tank inlet pipe. The sedimentation tank outlet pipe is connected to the filter inlet. The filter outlet is connected to the water purification tank inlet.

[0014] The first sand outlet, the second sand outlet, the first sand outlet of the sedimentation tank, the second sand outlet of the sedimentation tank, and the sand outlet of the filter are all connected to the sand inlet of the separation tank. The liquid outlet of the separation tank is connected to the first liquid inlet. The sand outlet of the separation tank is used to discharge the separated sand and gravel.

[0015] In one possible implementation, a first screw conveyor is installed at the first sand outlet of the sedimentation tank, and a second screw conveyor is installed at the second sand outlet of the sedimentation tank.

[0016] In one possible implementation, a vibrating screen is vertically fixed in the separation and filtration sedimentation tank, which divides the separation and filtration sedimentation tank into a turbulent zone and a still water zone.

[0017] The outlet of the sedimentation tank inlet pipe is located in the turbulent zone, and the inlet of the sedimentation tank outlet pipe is located in the still water zone.

[0018] In one possible implementation, a vibrating motor is fixedly mounted on the vibrating screen, and a waterproof housing is provided on the outside of the vibrating motor.

[0019] In one possible implementation, the turbulent zone is provided with a variable-angle guide plate, and the outlet of the sedimentation tank inlet pipe faces the variable-angle guide plate.

[0020] In one possible implementation, a support shaft extends forward and backward on one side of the variable angle guide plate, and the variable angle guide plate is rotatably connected to the front and rear walls of the turbulent zone via the support shaft.

[0021] A guide plate self-locking motor is fixedly installed on the front wall and / or rear wall of the turbulence zone, and the motor shaft of the guide plate self-locking motor is connected to the support shaft of the variable angle guide plate.

[0022] In one possible implementation, the bottom of the vibrating screen is higher than the bottom of the separation filtration sedimentation tank.

[0023] The bottom of the vibrating screen extends to the bottom of both sides of the separation filtration sedimentation tank with sand discharge inclined plates.

[0024] In one possible implementation, both the turbulent zone and the still water zone are equipped with level gauges.

[0025] The oilfield fracturing waste fluid desander device disclosed in this application has the following advantages:

[0026] By setting up sand-water separation tanks, the accumulated sand discharged from each sand outlet is dehydrated, and the separated clean water is returned to the first liquid inlet for circulation, which improves the sand removal and recovery rate and clean water utilization rate of oilfield fracturing waste fluid.

[0027] The proposed sedimentation tank has a first screw conveyor installed at the first sand outlet and a second screw conveyor installed at the second sand outlet, which improves the stability and efficiency of sand discharge.

[0028] The proposed vibrating screen is equipped with a vibrating motor, which is covered with a waterproof shell to prevent sand and gravel from clogging the screen, thereby improving the sand screening efficiency and the operational stability of the vibrating motor.

[0029] The proposed variable angle guide plate is rotatably connected to the front and rear walls of the turbulent zone via a support shaft. A guide plate self-locking motor is fixedly installed on the front and / or rear walls of the turbulent zone. The motor shaft of the guide plate self-locking motor is drivenly connected to the support shaft of the variable angle guide plate. The flow direction of the waste liquid can be controlled by adjusting the angle of the guide plate.

[0030] The proposed turbulent flow zone and still water zone are both equipped with level gauges, which can be used to monitor the liquid level in the turbulent flow zone and still water zone, thereby providing a basis for flow regulation. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic diagram of a sand removal device for oilfield fracturing waste fluid provided in this application embodiment;

[0033] Figure 2 This is a schematic diagram of the separation, filtration, and sedimentation tank provided in an embodiment of this application.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1-First cyclone sand separator, 2-Second cyclone sand separator, 3-Separation and filtration sedimentation tank, 4-Screen filter, 5-Clean water tank, 6-Sand-water separation tank, 11-First liquid inlet, 12-First sand outlet, 13-First liquid outlet, 21-Second liquid inlet, 22-Second sand outlet, 23-Second liquid outlet, 31-Sedimentation tank inlet pipe, 32-Sedimentation tank first sand outlet, 33-Sedimentation tank second sand outlet, 34-Sedimentation tank outlet pipe, 41 - Filter inlet, 42 - Filter sand outlet, 43 - Filter outlet, 51 - Clean water tank inlet, 61 - Separator sand inlet, 62 - Separator sand outlet, 63 - Separator outlet, 321 - First screw conveyor, 331 - Second screw conveyor, 35 - Vibrating screen, 351 - Vibrating motor, 36 - Turbulent zone, 37 - Still water zone, 38 - Variable angle guide plate, 381 - Guide plate self-locking motor, 39 - Sand discharge inclined plate. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] like Figure 1 As shown in the figure, this application provides an oilfield fracturing wastewater desanding device, including: a first cyclone desander 1, a second cyclone desander 2, a separation filtration sedimentation tank 3, a screen filter 4, a clean water tank 5, and a sand-water separation tank 6.

[0038] The first cyclone sand separator 1 is provided with a first liquid inlet 11, a first sand outlet 12, and a first liquid outlet 13.

[0039] The second cyclone sand separator 2 is provided with a second liquid inlet 21, a second sand outlet 22, and a second liquid outlet 23.

[0040] The separation and filtration sedimentation tank 3 is equipped with a sedimentation tank inlet pipe 31, a sedimentation tank first sand outlet 32, a sedimentation tank second sand outlet 33, and a sedimentation tank outlet pipe 34.

[0041] The filter screen 4 is provided with a filter inlet 41, a filter sand outlet 42, and a filter outlet 43.

[0042] The water purification tank 5 is equipped with a water purification tank inlet 51.

[0043] The sand-water separator 6 is provided with a sand inlet 61, a sand outlet 62, and a liquid outlet 63.

[0044] The first inlet 11 is used to input oilfield fracturing waste fluid. The first outlet 11 is connected to the second inlet 21. The second outlet 23 is connected to the sedimentation tank inlet pipe 31. The sedimentation tank outlet pipe 34 is connected to the filter inlet 41. The filter outlet 43 is connected to the water purification tank inlet 51.

[0045] The first sand outlet 12, the second sand outlet 22, the first sand outlet 32 ​​of the sedimentation tank, the second sand outlet 33 of the sedimentation tank, and the sand outlet 42 of the filter are all connected to the sand inlet 61 of the separation tank. The liquid outlet 63 of the separation tank is connected to the first liquid inlet 11. The sand outlet 62 of the separation tank is used to discharge the separated sand and gravel.

[0046] Specifically, the first hydrocyclone desander 1 is used for preliminary desandering of oilfield fracturing waste fluid, and the second hydrocyclone desander 2 is used for secondary desandering of oilfield fracturing waste fluid. The desandering accuracy of the second hydrocyclone desander 2 is higher than that of the first hydrocyclone desander 1. The separation and filtration sedimentation tank 3 is used for gas-liquid separation, filtration and desandering, and sedimentation desandering of oilfield fracturing waste fluid. The screen filter 4 is used for filtration and desandering of the liquid output from the separation and filtration sedimentation tank 3. The clean water tank 5 is used to collect the clean water output from the screen filter 4. The sand-water separation tank 6 is used to dewater the accumulated sand discharged from the first sand outlet 12, the second sand outlet 22, the first sand outlet 32 ​​of the sedimentation tank, the second sand outlet 33 of the sedimentation tank, and the sand outlet 42 of the filter, and returns the separated clean water to the first liquid inlet 11 for circulation. Each connected pipeline is equipped with a delivery pump.

[0047] like Figure 2 As shown, exemplarily, the first sand outlet 32 ​​of the sedimentation tank is equipped with a first screw conveyor 321, and the second sand outlet 33 of the sedimentation tank is equipped with a second screw conveyor 331.

[0048] For example, a vibrating screen 35 is vertically fixed in the separation and filtration sedimentation tank 3, and the vibrating screen 35 divides the separation and filtration sedimentation tank 3 into a turbulent zone 36 and a still water zone 37.

[0049] The outlet of the sedimentation tank inlet pipe 31 is located in the turbulent flow zone 36, and the inlet of the sedimentation tank outlet pipe 34 is located in the still water zone 37.

[0050] Specifically, the first screw conveyor 321 is used to transport the accumulated sand in the turbulent zone 36 from the first sand outlet 32 ​​of the sedimentation tank to the sand-water separation tank 6, and the second screw conveyor 331 is used to transport the accumulated sand in the still water zone 37 from the second sand outlet 33 of the sedimentation tank to the sand-water separation tank 6.

[0051] For example, a vibration motor 351 is fixedly installed on the vibrating screen 35, and a waterproof shell is provided on the outside of the vibration motor 351.

[0052] Specifically, by using a vibrating motor 351 to vibrate the vibrating screen 35, sand and gravel can be prevented from clogging the screen and the sand screening efficiency can be improved. The waterproof casing can prevent water from entering the vibrating motor 351 and improve the operational stability of the vibrating motor 351.

[0053] For example, the turbulent zone 36 is provided with a variable angle guide plate 38, and the outlet of the sedimentation tank inlet pipe 31 faces the variable angle guide plate 38.

[0054] For example, the variable angle guide plate 38 has a support shaft extending forward and backward on one side, and the variable angle guide plate 38 is rotatably connected to the front and rear walls of the turbulence zone 36 through the support shaft.

[0055] A guide plate self-locking motor 381 is fixedly installed on the front wall and / or rear wall of the turbulence zone 36, and the motor shaft of the guide plate self-locking motor 381 is connected to the support shaft of the variable angle guide plate 38.

[0056] Specifically, by adjusting the angle of the guide plate, the flow direction of the waste liquid can be controlled, thereby controlling the location of sand accumulation and preventing blockage.

[0057] For example, the bottom of the vibrating screen 35 is higher than the bottom of the separation filtration sedimentation tank 3.

[0058] The bottom of the vibrating screen 35 extends to the bottom of both sides of the separation filtration sedimentation tank 3, where sand discharge inclined plates 39 are provided.

[0059] Specifically, in this embodiment, the angle between the sand discharge inclined plate 39 and the bottom of the separation filtration sedimentation tank 3 is 30 degrees. In other possible embodiments, it can be set to other angles.

[0060] For example, both the turbulent zone 36 and the still water zone 37 are equipped with level gauges.

[0061] Specifically, monitoring the liquid levels in the turbulent zone 36 and the still water zone 37 using level gauges can provide a basis for flow regulation.

[0062] Specifically, in this embodiment, the working process of the oilfield fracturing waste fluid desander is as follows: the oilfield fracturing waste fluid is pumped from the first inlet 11 into the first cyclone desander 1; the desandered liquid from the first cyclone desander 1 is pumped from the first outlet 13 to the second inlet 21 and enters the second cyclone desander 2; the desandered liquid from the second cyclone desander 2 is pumped from the second outlet 23 to the settling tank inlet pipe 31 and enters the turbulent zone 36 of the separation and filtration settling tank 3, where gas-liquid separation occurs at the variable angle guide plate 38, followed by vibration filtration through the vibrating screen 35 to reach the still water zone 37; the liquid in the still water zone 37, after settling, is pumped from the settling tank outlet 34 to the filter inlet 41 and enters the screen filter 4; the filtered clean water from the screen filter 4 is pumped from the filter outlet 43 to the clean water tank inlet 51 and enters the clean water tank 5. During the above process, the accumulated sand is periodically pumped or conveyed from the first sand outlet 12, the second sand outlet 22, the first sand outlet 32 ​​of the sedimentation tank, the second sand outlet 33 of the sedimentation tank, and the sand outlet 42 of the filter to the sand inlet 61 of the separation tank, and enters the sand-water separation tank 6. The clean water separated by the sand-water separation tank 6 is pumped back from the liquid outlet 63 of the separation tank to the first liquid inlet 11 for circulation, and the sand and gravel separated by the sand-water separation tank 6 are recovered from the sand outlet 62 of the separation tank by conveying through a screw conveyor.

[0063] This embodiment of the application improves the sand removal and recovery rate and the water utilization rate of oilfield fracturing waste fluid by setting up a sand-water separation tank 6 to dehydrate the accumulated sand discharged from each sand outlet and return the separated clean water to the first liquid inlet 11 for circulation.

[0064] The proposed sedimentation tank has a first screw conveyor 321 installed at the first sand outlet 32 ​​and a second screw conveyor 331 installed at the second sand outlet 33, which improves the stability and efficiency of sand discharge.

[0065] The proposed vibrating screen 35 is fixedly equipped with a vibrating motor 351. The vibrating motor 351 is equipped with a waterproof shell, which can prevent sand and gravel from clogging, improve the sand screening efficiency, and improve the operating stability of the vibrating motor 351.

[0066] The proposed variable angle guide plate 38 is rotatably connected to the front and rear walls of the turbulent zone 36 via a support shaft. A guide plate self-locking motor 381 is fixedly installed on the front and / or rear walls of the turbulent zone 36. The motor shaft of the guide plate self-locking motor 381 is connected to the support shaft of the variable angle guide plate 38 via a transmission connection. The flow direction of the waste liquid can be controlled by adjusting the angle of the guide plate.

[0067] Both the turbulent flow zone 36 and the still water zone 37 are equipped with level gauges, which can monitor the liquid level in the turbulent flow zone 36 and the still water zone 37, thereby providing a basis for flow regulation.

[0068] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0069] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A sand removal device for oilfield fracturing waste fluid, characterized in that, include: First cyclone sand separator, second cyclone sand separator, separation filtration sedimentation tank, screen filter, water purification tank, sand-water separation tank; The first cyclone sand separator is provided with a first liquid inlet, a first sand outlet, and a first liquid outlet; The second cyclone sand separator is provided with a second liquid inlet, a second sand outlet, and a second liquid outlet; The separation and filtration sedimentation tank is equipped with a sedimentation tank inlet pipe, a sedimentation tank first sand outlet, a sedimentation tank second sand outlet, and a sedimentation tank outlet pipe. The filter screen is equipped with a filter inlet, a filter sand outlet, and a filter outlet. The purified water tank is equipped with a purified water tank inlet; The sand-water separator is equipped with a sand inlet, a sand outlet, and a liquid outlet. The first inlet is used to input oilfield fracturing waste fluid. The first outlet is connected to the second inlet. The second outlet is connected to the sedimentation tank inlet pipe. The sedimentation tank outlet pipe is connected to the filter inlet. The filter outlet is connected to the water purification tank inlet. The first sand outlet, the second sand outlet, the first sand outlet of the sedimentation tank, the second sand outlet of the sedimentation tank, and the sand outlet of the filter are all connected to the sand inlet of the separation tank. The liquid outlet of the separation tank is connected to the first liquid inlet. The sand outlet of the separation tank is used to discharge the separated sand and gravel.

2. The oilfield fracturing waste fluid desanding device according to claim 1, characterized in that, The first sand outlet of the sedimentation tank is equipped with a first screw conveyor, and the second sand outlet of the sedimentation tank is equipped with a second screw conveyor.

3. The oilfield fracturing waste fluid desanding device according to claim 1, characterized in that, A vibrating screen is vertically fixed in the separation and filtration sedimentation tank, which divides the separation and filtration sedimentation tank into a turbulent zone and a still water zone. The outlet of the sedimentation tank inlet pipe is located in the turbulent zone, and the inlet of the sedimentation tank outlet pipe is located in the still water zone.

4. The oilfield fracturing waste fluid desanding device according to claim 3, characterized in that, A vibrating motor is fixedly installed on the vibrating screen, and a waterproof shell is provided on the outside of the vibrating motor.

5. The oilfield fracturing waste fluid desanding device according to claim 3, characterized in that, The turbulent zone is equipped with a variable-angle guide plate, and the outlet of the sedimentation tank inlet pipe faces the variable-angle guide plate.

6. The oilfield fracturing waste fluid desanding device according to claim 5, characterized in that, The variable angle guide plate has a support shaft extending forward and backward on one side, and the variable angle guide plate is rotatably connected to the front and rear walls of the turbulent zone through the support shaft; A guide plate self-locking motor is fixedly installed on the front wall and / or rear wall of the turbulence zone, and the motor shaft of the guide plate self-locking motor is connected to the support shaft of the variable angle guide plate.

7. The oilfield fracturing waste fluid desanding device according to claim 3, characterized in that, The bottom of the vibrating screen is higher than the bottom of the separation and filtration sedimentation tank; The bottom of the vibrating screen extends to the bottom of both sides of the separation filtration sedimentation tank with sand discharge inclined plates.

8. The oilfield fracturing waste fluid desanding device according to claim 3, characterized in that, Both the turbulent flow zone and the still water zone are equipped with level gauges.

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