A fracturing flowback fluid collection system

Abstract

The present invention belongs to the technical field of fracturing fluid collection, and in particular, is a fracturing return fluid collection system, including a fracturing fluid return collection pipe section, a dual-axis motor, a connecting structure, a stirring structure, a transmission structure, a first liquid inlet pipe and a second liquid inlet pipe, a plurality of fracturing fluid return collection pipe sections are sequentially connected to form a whole pipe for collecting fracturing fluid return fluid, the head end of the whole pipe is connected to a pump, and the other tail end of the whole pipe is connected to a collection bucket; two adjacent fracturing fluid return collection pipe sections are connected by a flange connection structure; the stirring structure is installed inside the fracturing fluid return collection pipe section through a connecting structure, the connecting structure is arranged between two adjacent fracturing fluid return collection pipe sections, and a sealing arrangement is provided between the connecting structure and the connecting end of the fracturing fluid return collection pipe section. The present invention solves the problems of high viscosity of existing fracturing fluid return fluid, difficulty in collection, and difficulty in cleaning the collection pipe by coagulating, flocculating, and stirring the return waste liquid in the pipe.

Description

Technical Field

[0001] The invention relates to the technical field of fracturing fluid collection, in particular to a fracturing flowback fluid collection system. Background Art

[0002] Fracturing technology is one of the effective measures to increase production during the exploitation of oil and gas fields, and is widely used by major oil and gas fields. Fracturing refers to a method of using hydraulic force to form cracks in oil and gas layers during oil or gas production, also known as hydraulic fracturing. Fracturing is the process of artificially creating cracks in the formation to improve the flow environment of oil underground and increase the production of oil wells. It plays an important role in improving the flow conditions at the bottom of the oil well, slowing down the interlayer and improving the utilization of the oil layer. During fracturing, a fracturing truck is generally used to inject high-pressure, large-volume fracturing fluid into the well to press the formation open and squeeze the fracturing sand and proppant into the cracks.

[0003] During the fracturing construction process, a large amount of fracturing flowback waste liquid will be generated, mainly flowback fracturing fluid, groundwater and drill cuttings. The composition of fracturing flowback waste liquid is complex, generally including a large amount of thickener (usually guar gum), cross-linking agent, degelling agent and other chemical additives, with a certain pungent odor, which is harmful to both human body and environment. The usual treatment method is to collect them in a centralized manner, and through chemical methods, use flocculants to flocculate the colloidal particles to destabilize them, forming flocs, thereby separating the suspended matter, oil and water in the waste liquid, so that the treated water quality meets the needs of reuse.

[0004] The existing fracturing fluid backflow waste liquid collection pipe cannot pre-flocculate the backflow fluid, the backflow fluid backend processing efficiency is low, and the viscosity is high, making it difficult to collect the backflow fluid and clean the collection pipe. Summary of the invention

[0005] In view of the deficiencies of the prior art, the present invention provides a fracturing flowback fluid collection system, which solves the problems of the prior fracturing fluid flowback fluid.

[0006] (2) Technical solution

[0007] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:

[0008] A fracturing flowback fluid collection system, the fracturing flowback fluid collection system comprising:

[0009] There are a plurality of fracturing fluid return collection pipe sections, which are connected in sequence to form a whole pipe for collecting fracturing fluid return fluid, wherein the first end of the whole pipe is connected to a pump, and the other end of the whole pipe is connected to a collection bucket;

[0010] Two adjacent fracturing fluid flowback collection pipe sections are connected via a flange connection structure;

[0011] A double-shaft motor, having two left and right motor shafts, the two motor shafts are connected through the same rotor, and the double-shaft motor is fixedly installed on the fracturing fluid return collection pipe section;

[0012] A connecting structure and a stirring structure, wherein the stirring structure is installed inside the fracturing fluid return collection pipe section through the connecting structure, the connecting structure is arranged between two adjacent fracturing fluid return collection pipe sections, and a sealing arrangement is provided between the connecting structure and the connecting end of the fracturing fluid return collection pipe section;

[0013] A transmission structure, wherein the transmission structure is rotatably mounted on the flange connection structure, and two transmission structures are provided, and the two transmission structures are respectively connected to the two motor shaft ends of the dual-axis motor;

[0014] The transmission structure and the connection structure are connected by gear meshing, driving the connection structure to perform circular motion around the central axis of the fracturing fluid return collection pipe section, and then driving the stirring structure connected to the connection structure to stir the fracturing fluid return fluid introduced into the fracturing fluid return collection pipe section;

[0015] A first liquid inlet pipe, the first liquid inlet pipe is connected to the fracturing fluid return collection pipe section at the head end near the pump, and the first liquid inlet pipe is used to introduce a coagulant into the fracturing fluid return collection pipe section to reduce the viscosity of the fracturing fluid return fluid in the fracturing fluid return collection pipe section;

[0016] The second liquid inlet pipe is connected to the fracturing fluid return collection pipe section in the middle part, and the second liquid inlet pipe is used to introduce flocculant into the fracturing fluid return collection pipe section to pre-flocculate the fracturing fluid return fluid in the fracturing fluid return collection pipe section.

[0017] Furthermore, the flange connection structure includes a butt end and a connection flange arranged on the butt end, each connection structure is respectively arranged between two adjacent butt ends, a gap is provided between the two adjacent butt ends, the two adjacent connection flanges are locked by bolts and nuts, and the connection flange is also provided with a mounting hole;

[0018] The connection structure comprises an outer ring plate and an inner ring plate, wherein the outer ring plate is mounted on two adjacent butt ends through a first bearing, an outer wall of the outer ring plate is provided with external teeth, the inner ring plate is connected to the middle position of the inner ring wall of the outer ring plate, the inner ring plate is arranged in the gap between the two adjacent butt ends, and the connection between the inner ring plate and the butt ends is sealed and connected by a sealing ring;

[0019] The stirring structure is composed of a connecting rib plate and a stirring rod, and a plurality of the connecting rib plates and the stirring rod are provided. The plurality of connecting rib plates are circumferentially arranged between two adjacent inner ring plates, and the outer edge of the connecting rib plate is in contact with the inner wall of the fracturing fluid return collection pipe section. A plurality of stirring rods are equidistantly arranged on each connecting rib plate, and the connecting rib plate and the stirring rod are arranged perpendicular to each other;

[0020] The transmission structure is composed of a transmission rod and a transmission gear. The transmission rod is installed in a mounting hole on the connecting flange through a second bearing. The transmission gear is fixed on the transmission rod and meshes with the external teeth.

[0021] Furthermore, the outer teeth and the transmission gear are provided in pairs respectively, and the outer teeth and the transmission gear are meshed one by one.

[0022] Furthermore, a control valve is provided on the first liquid inlet pipe and the second liquid inlet pipe respectively.

[0023] (III) Beneficial effects

[0024] Compared with the prior art, the present invention provides a fracturing flowback fluid collection system, which has the following beneficial effects:

[0025] The present invention introduces a coagulant into a fracturing fluid return collection pipe section through a first liquid inlet pipe, and utilizes the coagulation effect of the coagulant to reduce the viscosity of the fracturing fluid return fluid, making it easier to collect; then, a flocculant is introduced into the pipeline through a second liquid inlet pipe to pre-flocculate the return fluid, thereby reducing the flocculation treatment time of the fracturing fluid return fluid and improving the fracturing fluid treatment efficiency; in order to solve the problem of pipeline cleaning difficulties, the present invention adds a dual-axis motor, a connecting structure, a stirring structure and a transmission structure to the collection pipeline, wherein the dual-axis motor provides power, which is transmitted through the connecting structure and the transmission structure, thereby driving the stirring structure in the pipeline to achieve a stirring effect on the return fluid in the pipeline, and the stirring structure can clean the inner pipe wall, and at the same time, can make the coagulant and flocculant mix more fully with the return fluid, and the coagulation and flocculation speeds are faster and the effect is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the fracturing flowback fluid collection system of the present invention; Figure 2 for Figure 1 The enlarged view of point A in the middle;

[0027] Figure 3 It is a schematic diagram of the structure of the fracturing fluid flowback collection pipe section in the present invention;

[0028] Figure 4 It is a schematic diagram of the connection structure between the connecting structure and the stirring structure of the present invention.

[0029] In the figure: 1. Fracturing fluid return collection pipe section; 2. Flange connection structure; 201. Butt end; 202. Connection flange; 3. Dual-axis motor; 4. Connection structure; 401. External ring plate; 402. Internal ring plate; 403. First bearing; 404. External gear; 405. Sealing ring; 5. Stirring structure; 501. Connecting rib plate; 502. Stirring rod; 6. Transmission structure; 601. Transmission rod; 602. Transmission gear; 7. First liquid inlet pipe; 8. Second liquid inlet pipe; 9. Pump; 10. Collection barrel. DETAILED DESCRIPTION

[0030] 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.

[0031] Example

[0032] like Figure 1-4 As shown, an embodiment of the present invention proposes a fracturing return fluid collection system, which is mainly composed of a fracturing fluid return collection pipe section 1, a pump 9, a collection barrel 10, a dual-axis motor 3, a connecting structure 4, a stirring structure 5, a transmission structure 6, a first liquid inlet pipe 7 and a second liquid inlet pipe 8.

[0033] There are a plurality of fracturing fluid return collection pipe sections 1, which are connected in sequence to form a whole pipe for collecting fracturing fluid return fluid. The first end of the whole pipe is connected to a pump 9, and the other end of the whole pipe is connected to a collection bucket 10. Two adjacent fracturing fluid return collection pipe sections 1 are connected by a flange connection structure 2.

[0034] The double-shaft motor 3 has two left and right motor shafts, the two motor shafts are connected through the same rotor, and the double-shaft motor 3 is fixedly installed on the fracturing fluid return collection pipe section 1;

[0035] The stirring structure 5 is installed inside the fracturing fluid return collection pipe section 1 through the connecting structure 4. The connecting structure 4 is arranged between two adjacent fracturing fluid return collection pipe sections 1. The connecting structure 4 and the connecting end of the fracturing fluid return collection pipe section 1 are sealed.

[0036] The transmission structure 6 is rotatably mounted on the flange connection structure 2. Two transmission structures 6 are provided. The two transmission structures 6 are respectively connected to the two motor shaft ends of the dual-axis motor 3.

[0037] The transmission structure 6 is connected to the connection structure 4 by means of tooth meshing, driving the connection structure 4 to make a circular motion around the central axis of the fracturing fluid return collection pipe section 1, and then driving the stirring structure 5 connected to the connection structure 4 to stir the fracturing fluid return fluid introduced into the fracturing fluid return collection pipe section 1;

[0038] A first liquid inlet pipe 7, which is connected to the fracturing fluid return collection pipe section 1 at the head end near the pump 9, and is used to introduce a coagulant into the fracturing fluid return collection pipe section 1 to reduce the viscosity of the fracturing fluid return fluid in the fracturing fluid return collection pipe section 1;

[0039] The second liquid inlet pipe 8 is connected to the fracturing fluid return collection pipe section 1 in the middle part, and is used to introduce flocculant into the fracturing fluid return collection pipe section 1 to pre-flocculate the fracturing fluid return liquid in the fracturing fluid return collection pipe section 1.

[0040] The present invention mainly solves the problems of high viscosity, difficulty in collection and difficulty in cleaning of the collection pipeline of the existing fracturing fluid return fluid by the above implementation scheme; the present invention arranges a first liquid inlet pipe 7 at the front end of the collection pipe, and introduces a coagulant into the fracturing fluid return collection pipe section 1 through the first liquid inlet pipe 7, and reduces the viscosity of the fracturing fluid return fluid by utilizing the coagulation effect of the coagulant, so as to facilitate collection; and then introduces a flocculant into the pipeline through a second liquid inlet pipe 8 in the middle section of the collection pipe, and pre-flocculates the return fluid, thereby reducing the flocculation treatment time of the fracturing fluid return fluid and improving the fracturing fluid treatment efficiency; in order to solve the problem of difficult pipeline cleaning, the present invention adds a dual-axis motor 3, a connecting structure 4, a stirring structure 5 and a transmission structure 6 to the collection pipeline, the dual-axis motor 3 provides power, and is transmitted through the connecting structure 4 and the transmission structure 6, so as to drive the stirring structure 5 in the pipe to achieve the stirring effect on the return fluid in the pipe, and the stirring structure 5 can clean the inner pipe wall, and at the same time can make the coagulant and flocculant mix more fully with the return fluid, and the coagulation and flocculation speed is faster and the effect is better.

[0041] like Figure 2 and Figure 3 As shown, in some embodiments, the flange connection structure 2 includes a butt end 201 and a connection flange 202 arranged on the butt end 201, each connection structure 4 is respectively arranged between two adjacent butt ends 201, a gap is provided between the two adjacent butt ends 201, and the two adjacent connection flanges 202 are locked by bolts and nuts, and the connection flange 202 is also provided with a mounting hole;

[0042] like Figure 2 and Figure 4As shown, the connection structure 4 includes an outer ring plate 401 and an inner ring plate 402. The outer ring plate 401 is installed on two adjacent butt ends 201 through a first bearing 403. An outer tooth 404 is provided on the outer wall of the outer ring plate 401. The inner ring plate 402 is connected to the middle position of the inner ring wall of the outer ring plate 401. The inner ring plate 402 is arranged in the gap between the two adjacent butt ends 201, and the connection between the inner ring plate 402 and the butt ends 201 is sealed and connected by a sealing ring 405.

[0043] like Figure 2 and Figure 4 As shown, the stirring structure 5 is composed of a connecting rib plate 501 and a stirring rod 502, and a plurality of connecting rib plates 501 and stirring rods 502 are provided. The plurality of connecting rib plates 501 are circumferentially arranged between two adjacent inner ring plates 402, and the outer edge of the connecting rib plate 501 is in contact with the inner wall of the fracturing fluid return collection pipe section 1. A plurality of stirring rods 502 are equidistantly provided on each connecting rib plate 501, and the connecting rib plate 501 and the stirring rod 502 are arranged perpendicular to each other;

[0044] like Figure 2 As shown, the transmission structure 6 is composed of a transmission rod 601 and a transmission gear 602 . The transmission rod 601 is installed in the mounting hole on the connecting flange 202 through a second bearing. The transmission gear 602 is fixed on the transmission rod 601 , and the transmission gear 602 is meshed with the external teeth 404 .

[0045] In the above embodiment, the connecting structure 4, the stirring structure 5 and the transmission structure 6 form a synergistic device integrating cleaning, viscosity reduction and flocculation. When in use, the motor shaft of the dual-axis motor 3 drives the transmission rod 601 in the transmission structure 6 to rotate, and the transmission rod 601 drives the transmission gear 602 thereon to rotate. Since the transmission gear 602 is meshed with the outer teeth 404 on the outer ring plate 401 in the connecting structure 4, when the transmission gear 602 rotates, it will drive the outer ring plate 401 meshed with it to make a circular motion between the pipe sections, and the inner ring plate 402 moves synchronously with the outer ring plate 401, thereby driving the stirring structure 5 connected to the inner ring plate 402 to rotate, and the connecting rib plate 501 in the stirring structure 5 is in contact with the inner wall of the fracturing fluid return collection pipe section 1. In this way, when the connecting rib plate 501 makes a circular motion, it will play a role in scraping the wall, which is convenient for cleaning the residue in the pipe and preventing the return fluid in the pipe from adhering to the pipe wall, so as to achieve the purpose of facilitating the cleaning of the pipeline.

[0046] It should be noted that, in order to improve the collection effect of the collecting pipe, the present invention also connects a water inlet pipe (not shown in the figure) to the front end of the collecting pipe, and connects a water outlet pipe (not shown in the figure) to the rear end of the collecting pipe; the function of the water inlet pipe is to transport cleaning liquid into the collecting pipe through the water inlet pipe after the collection is completed, and discharge it to the corresponding sewage treatment system through the water outlet pipe. This structural design can fully clean the collecting pipe and maintain the cleanliness of the collecting pipe.

[0047] like Figure 2 As shown, in some embodiments, two external teeth 404 and two transmission gears 602 are respectively provided, and the external teeth 404 and the transmission gears 602 are meshed one by one; two transmission gears 602 are provided, which are respectively located on both sides of the inner ring plate 402, and the cooperation of the two symmetrically arranged transmission gears 602 and the corresponding two external teeth 404 can make the transmission more stable and reliable.

[0048] like Figure 1 As shown, in some embodiments, a control valve is respectively provided on the first liquid inlet pipe 7 and the second liquid inlet pipe 8; the provision of the control valve facilitates the implementation of liquid inlet control.

[0049] In another aspect of the present invention, the number of dual-axis motors 3, the resistance inside the tube and other factors can be increased or decreased according to the length of the collection tube. To avoid excessive resistance, the rotation speed of the connecting rib plate 501 and the stirring rod 502 in the stirring structure 5 should not be too fast to ensure the overall stable operation of the device.

[0050] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A fracturing flowback fluid collection system, characterized in that: The fracturing flowback fluid collection system comprises: A plurality of fracturing fluid return collection pipe sections (1) are provided, and the plurality of fracturing fluid return collection pipe sections (1) are connected in sequence to form a whole pipe for collecting fracturing fluid return fluid, wherein the first end of the whole pipe is connected to a pump (9), and the other end of the whole pipe is connected to a collection bucket (10); Two adjacent fracturing fluid return collection pipe sections (1) are connected via a flange connection structure (2); the flange connection structure (2) comprises a butt end (201) and a connection flange (202) arranged on the butt end (201); each connection structure (4) is arranged between two adjacent butt ends (201); a gap is provided between the two adjacent butt ends (201); the two adjacent connection flanges (202) are locked by bolts and nuts; and a mounting hole is also provided on the connection flange (202); A double-shaft motor (3) having two left and right motor shafts, the two motor shafts being connected via a common rotor, the double-shaft motor (3) being fixedly mounted on a fracturing fluid return collection pipe section (1); A connecting structure (4) and a stirring structure (5), wherein the stirring structure (5) is installed inside the fracturing fluid return collection pipe section (1) through the connecting structure (4), the connecting structure (4) is arranged between two adjacent fracturing fluid return collection pipe sections (1), and a sealing arrangement is provided between the connecting structure (4) and the connecting end of the fracturing fluid return collection pipe section (1); The connection structure (4) comprises an outer ring plate (401) and an inner ring plate (402), the outer ring plate (401) being mounted on two adjacent butt ends (201) via a first bearing (403), an outer wall of the outer ring plate (401) being provided with external teeth (404), the inner ring plate (402) being connected to a middle position of an inner ring wall of the outer ring plate (401), the inner ring plate (402) being arranged in a gap between two adjacent butt ends (201), and a connection between the inner ring plate (402) and the butt ends (201) being sealed via a sealing ring (405); The stirring structure (5) is composed of a connecting rib plate (501) and a stirring rod (502), and a plurality of the connecting rib plates (501) and the stirring rod (502) are provided. The plurality of connecting rib plates (501) are circumferentially arranged between two adjacent inner ring plates (402), and the outer edge of the connecting rib plate (501) is in contact with the inner wall of the fracturing fluid return collection pipe section (1). A plurality of stirring rods (502) are equidistantly arranged on each connecting rib plate (501), and the connecting rib plates (501) and the stirring rods (502) are arranged perpendicular to each other. A transmission structure (6), the transmission structure (6) being rotatably mounted on the flange connection structure (2), two transmission structures (6) being provided, and the two transmission structures (6) being respectively connected to two motor shaft ends of the dual-axis motor (3); The transmission structure (6) and the connection structure (4) are connected by means of tooth meshing, driving the connection structure (4) to perform circular motion around the central axis of the fracturing fluid return collection pipe section (1), thereby driving the stirring structure (5) connected to the connection structure (4) to stir the fracturing fluid return fluid introduced into the fracturing fluid return collection pipe section (1); The transmission structure (6) is composed of a transmission rod (601) and a transmission gear (602); the transmission rod (601) is mounted in a mounting hole on the connecting flange (202) via a second bearing; the transmission gear (602) is fixed on the transmission rod (601), and the transmission gear (602) is meshed with the external teeth (404); A first liquid inlet pipe (7), the first liquid inlet pipe (7) being connected to the fracturing fluid flowback collection pipe section (1) at the head end close to the pump (9), the first liquid inlet pipe (7) being used to introduce a coagulant into the fracturing fluid flowback collection pipe section (1) to reduce the viscosity of the fracturing fluid flowback liquid in the fracturing fluid flowback collection pipe section (1); A second liquid inlet pipe (8), the second liquid inlet pipe (8) is connected to the fracturing fluid flowback collection pipe section (1) at the middle portion, and the second liquid inlet pipe (8) is used to introduce a flocculant into the fracturing fluid flowback collection pipe section (1) to pre-flocculate the fracturing fluid flowback liquid in the fracturing fluid flowback collection pipe section (1).

2. A fracturing flowback fluid collection system according to claim 1, characterized in that: The outer teeth (404) and the transmission gear (602) are respectively provided with two, and the outer teeth (404) and the transmission gear (602) are meshed one by one.

3. A fracturing flowback fluid collection system according to claim 1, characterized in that: The first liquid inlet pipe (7) and the second liquid inlet pipe (8) are each provided with a control valve.

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