A device for filtering and purifying drilling fracturing flowback fluid

Abstract

The utility model relates to the field of petroleum and natural gas engineering technology discloses a kind of drilling fracturing flowback fluid filtration purification device, including shell, the inside fixed mounting of shell has the mixing cylinder and two purification cylinders to the flowback fluid and flocculating agent mixing, one of purification cylinders is used to filter large impurities, and another purification cylinder is used to filter flocculation after the flocculation of flowback fluid and flocculating agent, two purification cylinders one end all pass through shell, and one of purification cylinders is fixedly connected with the communication frame between mixing cylinder. This kind of drilling fracturing flowback fluid filtration purification device, by setting two purification cylinders, respectively filter larger impurities and the flocculation of flowback fluid and flocculating agent after mixing formed flocculation, flowback fluid is first filtered through filter screen to remove larger particle impurities, reduce main filtration unit load;Flowback fluid mixes with flocculating agent, liquid is pumped into second purification cylinder, and the flocculation formed after reaction is filtered out;Final discharge, multistage filtration design improves water quality and purification efficiency.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas engineering technology, specifically to a drilling fracture flowback fluid filtration and purification device. Background Technology

[0002] Oil and gas engineering is a comprehensive engineering and technical field involving the exploration, development, production, storage, transportation, and comprehensive utilization of oil and gas resources. Its core objective is to achieve efficient, safe, and environmentally friendly extraction and utilization of oil and gas resources through scientific methods and advanced technologies. This field encompasses multiple sub-disciplines such as geological exploration, drilling engineering, oil and gas production engineering, oil and gas storage and transportation engineering, and oilfield chemical engineering. It involves the integration of technologies across the entire industrial chain from underground resource discovery to end product delivery. Among these, flowback fluid is a mixed liquid that is flowed back from the formation to the surface after hydraulic fracturing operations. Its composition is complex and it presents significant environmental and engineering challenges.

[0003] An existing patent (publication number: CN221821964U) discloses a flowback fluid purification device for oilfield fracturing. This utility model solves the problem that existing flowback fluid purification devices do not have the ability to screen and filter larger stones in the flowback fluid during purification. The flowback fluid purification device for oilfield fracturing includes a shell, a shell cover fixedly connected to the upper surface of the shell, a water inlet on the upper surface of the shell cover, and the water inlet communicating with the inside of the shell. A collection box is fixedly connected to the lower surface of the shell, a bracket is fixedly connected to the outer surface of the shell, a feed shell is fixedly connected to one side of the shell, and a feeding port and a feed inlet are fixedly connected to the upper surface of the feed shell. The inside of the feeding port and the feed inlet are both connected to the inside of the feed shell. A stirring mechanism for stirring the flowback fluid is connected through one side of the shell. This realizes the effect of the flowback fluid purification device in first screening and filtering larger stones in the flowback fluid before purification.

[0004] When the above-mentioned device is in use, it achieves the effect of screening and filtering larger stones in the backflow liquid before purifying it. However, during the purification process, as filter plates A and B filter larger stones, smaller impurities will adhere to filter plate B. The fixed installation of the electric push rod and filter plate B makes it difficult to clean the impurities on filter plate B, thus affecting the subsequent purification effect of the backflow liquid. Utility Model Content

[0005] To achieve the above objectives, this utility model provides the following technical solution: a drilling fracturing flowback fluid filtration and purification device, comprising a housing, wherein a mixing cylinder for mixing flowback fluid and flocculant and two purification cylinders are fixedly installed inside the housing, one purification cylinder is used to filter large impurities, and the other purification cylinder is used to filter flocculent matter after mixing with flocculant, one end of each purification cylinder passes through the housing, a connecting frame is fixedly connected between one purification cylinder and the mixing cylinder, and an L-shaped discharge frame is fixedly connected to the circumferential surface of the other purification cylinder, one end of the discharge frame passes through the housing, and a first filter plate is installed on the inner wall of the discharge frame; both purification cylinders are provided with a filtration and discharge assembly for discharging impurities; the mixing cylinder is provided with a mixing assembly for mixing flowback fluid and flocculant.

[0006] Furthermore, the filtration and emission assembly includes a rotating rod rotatably connected to the inner wall of the purification cylinder, a cleaning auger fixedly connected to the circumferential surface of the rotating rod, and a second filter plate fixedly installed on the circumferential surface of the purification cylinder. The second filter plate has an arc-shaped structure, and the cleaning auger and the second filter plate are in contact with the inner wall of the purification cylinder.

[0007] With the above solution, the cleaning auger can clean the second filter plate while being driven to rotate by the rotating rod, and at the same time push the residue attached to the second filter plate out of the purification cylinder to prevent impurities from being trapped inside the purification cylinder.

[0008] Furthermore, one end of each of the two rotating rods is connected to a pulley via a belt.

[0009] With the above scheme, the two rotating rods are connected to the belt and pulley via a belt drive, so that the cleaning augers in the two purification cylinders can rotate synchronously.

[0010] Furthermore, a conical flow frame is fixedly connected to the inner wall of the housing, and the flow frame is fixedly connected to one of the purification cylinders. A filter screen is fixedly installed on the inner wall of the flow frame.

[0011] Through the above scheme, the conical flow frame can converge and guide the backflow liquid, and the filter screen can initially filter larger particulate impurities in the backflow liquid, reducing the filtration burden on the subsequent purification cartridge.

[0012] Furthermore, the mixing assembly includes a rotating column rotatably connected to the inner wall of the housing. One end of the rotating column is connected to one of the rotating rods via a belt and pulley. The rotating column is rotatably connected to the mixing cylinder via a sealed bearing. Multiple stirring plates are fixedly connected to the circumferential surface of the rotating column, and each stirring plate is inclined about the axis of the rotating column.

[0013] With the above scheme, during the rotation of the rotating column, one of the rotating rods can be driven to rotate through the belt drive to realize the transmission of power. At the same time as the rotating column rotates, the flocculant and the return liquid in the mixing drum can be stirred by the stirring plate to make the two fully mixed. The stirring plate is set at an angle with the axis of the rotating column, which can make the return liquid flow axially during the stirring process, and can make the flocculent material generated by the mixing of impurities and flocculant flow to the end of the mixing drum.

[0014] Furthermore, the mixing assembly also includes a discharge pipe fixedly installed on the inner wall of the mixing cylinder, with multiple nozzles evenly distributed along its axis fixedly connected to the circumferential surface of the discharge pipe; a compression cylinder fixedly installed on the inner wall of the housing, with a piston slidably connected inside the compression cylinder; a spring fixedly connected between the piston and the compression cylinder; two one-way valves fixedly connected to the circumferential surface of the compression cylinder; a liquid storage frame fixedly installed at the bottom end of the housing; an inlet pipe fixedly connected to one side of the liquid storage frame; one end of the discharge pipe fixedly connected to one of the one-way valves via a pipe; and the bottom end of the liquid storage frame fixedly connected to the other one-way valve via a pipe.

[0015] With the above scheme, the two one-way valves discharge in opposite directions, enabling the compression cylinder to extract flocculant from the storage box and deliver flocculant to the discharge pipe during the piston reciprocating motion, respectively, thus ensuring a stable supply of flocculant. The nozzles, which are evenly distributed along the axis of the discharge pipe, can evenly spray the flocculant into the mixing cylinder.

[0016] Furthermore, the hybrid assembly also includes a cam fixedly connected to the circumferential surface of a rotating rod, and the end of the piston near the cam is spherical and in contact with the cam.

[0017] With the above scheme, the cam fixedly connected to the circumference of the rotating rod can periodically squeeze the piston as the rotating rod rotates, causing the piston to reciprocate inside the compression cylinder, thereby realizing the function of automatically extracting and conveying flocculant.

[0018] Furthermore, a pump body is fixedly installed at the bottom of the housing. The water inlet of the pump body is connected to the mixing cylinder through a pipe passing through the housing. The drain of the pump body is connected to the purification cylinder opposite to the direction of the liquid storage frame through a pipe.

[0019] With the above scheme, the pump body can quickly transport the return liquid mixed with flocculant in the mixing drum to the corresponding purification drum for filtration.

[0020] Furthermore, a protective frame for protecting the belt drive is fixedly installed on the side of the housing.

[0021] The above solution enables the protective frame to protect the belt drive components and prevent external debris from entering the belt drive system.

[0022] Compared with the prior art, the technical solution of this utility model has the following beneficial effects: A drilling fracturing flowback fluid filtration and purification device features two purification cylinders. These cylinders filter larger impurities and flocculent material formed after the flowback fluid is mixed with flocculant, respectively. First, the flowback fluid passes through a filter screen to remove larger particles, reducing the load on the main filtration unit. After mixing with flocculant, the liquid is pumped into the second purification cylinder to filter out the resulting flocculent material. Finally, the mixture is discharged. This multi-stage filtration design improves the quality and efficiency of the effluent. Second, each purification cylinder contains a filter discharge assembly consisting of a rotating rod and a cleaning auger. The cleaning auger rotates with the rod, continuously scraping and cleaning the surface of the second filter plate, while simultaneously pushing and discharging trapped solid impurities from the purification cylinder. This self-cleaning function prevents clogging of the second filter plate, which would affect the purification efficiency of the flowback fluid. Finally, a mixing assembly not only achieves uniform mixing of the flowback fluid and flocculant through a stirring plate but also automatically and quantitatively delivers flocculant from the storage container into the mixing cylinder via a cam-driven piston and a one-way valve, enabling automated quantitative drug delivery. Attached Figure Description

[0023] Figure 1 Cross-sectional view of the overall structure of this application Figure 1 ; Figure 2 This is a schematic diagram of the overall internal structure of this application. Figure 1 ; Figure 3 This is a schematic diagram of the overall internal structure of this application. Figure 2 ; Figure 4 Cross-sectional view of the overall structure of this application Figure 2 ; Figure 5 For this application Figure 4 Enlarged schematic diagram of the structure at point A; Figure 6 This is a schematic diagram of the mixing plate structure of this application; Figure 7 This is a schematic diagram of the overall structure of this application. Figure 1 ; Figure 8 This is a schematic diagram of the overall structure of this application. Figure 2 ; Figure 9 This is a schematic diagram of the emission frame structure of this application.

[0024] In the diagram: 1. Shell; 2. Mixing cylinder; 3. Purification cylinder; 4. Connecting frame; 5. Discharge frame; 6. First filter plate; 7. Filter discharge assembly; 701. Rotary rod; 702. Cleaning auger; 703. Second filter plate; 8. Mixing assembly; 801. Rotating column; 802. Stirring plate; 803. Discharge pipe; 804. Nozzle; 805. Compression cylinder; 806. Piston; 807. Spring; 808. One-way valve; 809. Cam; 810. Liquid storage box; 811. Liquid inlet pipe; 9. Flow frame; 10. Filter screen; 11. Pump body; 12. Protective frame. Detailed Implementation

[0025] 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.

[0026] Please see Figures 1-9 This embodiment of a drilling fracturing flowback fluid filtration and purification device includes a housing 1. Inside the housing 1, a mixing cylinder 2 for mixing flowback fluid and flocculant and two purification cylinders 3 are fixedly installed. The two purification cylinders 3 are symmetrically arranged. One purification cylinder 3 is used to filter large impurities, while the other purification cylinder 3 is used to filter flocculent matter after mixing with flocculant. One end of each purification cylinder 3 passes through the housing 1. One purification cylinder 3 is fixedly connected to the mixing cylinder 2 by a connecting frame 4, while the circumferential surface of the other purification cylinder 3 is fixedly connected to an L-shaped discharge frame 5. One end of the discharge frame 5 passes through the housing 1, and a first filter plate 6 is installed on the inner wall of the discharge frame 5. The mixing cylinder 2 is fixedly connected to the inner bottom wall of the housing 1. The first filter plate 6 is specifically a polypropylene filter plate. Polypropylene filter plates have good chemical stability and are resistant to acid and alkali corrosion, and can effectively filter impurities. The interior of each purification cylinder 3 is provided with a filtration and discharge assembly 7 for discharging impurities, and the interior of the mixing cylinder 2 is provided with a mixing assembly 8 for mixing flowback fluid and flocculant.

[0027] The filtration and discharge assembly 7 includes a rotating rod 701 rotatably connected to the inner wall of the purification cylinder 3. A cleaning auger 702 is fixedly connected to the circumferential surface of the rotating rod 701. A second filter plate 703 is fixedly installed on the circumferential surface of the purification cylinder 3. The second filter plate 703 has an arc-shaped structure. The cleaning auger 702 and the second filter plate 703 are in contact with the inner wall of the purification cylinder 3. The cleaning auger 702 can clean the second filter plate 703 while the rotating rod 701 is driven to rotate. At the same time, it can push the residue attached to the second filter plate 703 out of the purification cylinder 3 to prevent impurities from being retained in the purification cylinder 3. One end of the two rotating rods 701 is connected to the pulley via a belt. The two rotating rods 701 are connected to the pulley via a belt, so that the cleaning augers 702 in the two purification cylinders 3 can rotate synchronously.

[0028] A conical flow frame 9 is fixedly connected to the inner wall of the housing 1. The flow frame 9 is fixedly connected to one of the purification cylinders 3. A filter screen 10 is fixedly installed on the inner wall of the flow frame 9. The conical flow frame 9 can collect and guide the backflow liquid. The filter screen 10 can initially filter larger particulate impurities in the backflow liquid, reducing the filtration burden on the subsequent purification cylinder 3.

[0029] The mixing assembly 8 includes a rotating column 801 rotatably connected to the inner wall of the housing 1. One end of the rotating column 801 is connected to one of the rotating rods 701 via a belt and pulley drive. The other end of the rotating column 801 is fixedly connected to the output end of an external motor. The rotating column 801 is rotatably connected to the mixing cylinder 2 via a sealed bearing. Multiple stirring plates 802 are fixedly connected to the circumferential surface of the rotating column 801. Each stirring plate 802 is inclined about the axis of the rotating column 801. During the rotation of the rotating column 801, it can drive one of the rotating rods 701 to rotate via belt drive, realizing the transmission of power. While the rotating column 801 is rotating, it can also drive one of the rotating rods 701 to rotate. The flocculant and backflow liquid in the mixing cylinder 2 are stirred by the stirring plate 802 to ensure thorough mixing. The stirring plate 802 is inclined about the axis of the rotating column 801, which causes axial flow of the backflow liquid during stirring, allowing the flocculent material formed by the mixing of impurities and flocculant to flow to the end of the mixing cylinder 2. The mixing assembly 8 also includes a discharge pipe 803 fixedly installed on the inner wall of the mixing cylinder 2. Multiple nozzles 804 are fixedly connected to the circumferential surface of the discharge pipe 803 and are distributed at equal intervals along its axis. A compression cylinder 805 is fixedly installed on the inner wall of the housing 1. A piston 806 is slidably connected inside the compression cylinder 805. The piston 806 and... A spring 807 is fixedly connected between the compression cylinders 805. Two one-way valves 808 are fixedly connected to the circumferential surface of the compression cylinders 805. The discharge directions of the two one-way valves 808 are opposite. A liquid storage frame 810 is fixedly installed at the bottom of the housing 1. An inlet pipe 811 is fixedly connected to one side of the liquid storage frame 810. One end of the discharge pipe 803 is fixedly connected to one of the one-way valves 808 through a pipe. The bottom end of the liquid storage frame 810 is fixedly connected to the other one-way valve 808 through a pipe. The discharge directions of the two one-way valves 808 are opposite, so that the compression cylinders 805 can extract flocculant from the liquid storage frame 810 during the reciprocating motion of the piston 806. The mixing assembly 8 also includes a cam 809 fixedly connected to the circumferential surface of a rotating rod 701. The piston 806 is spherically shaped and contacts the cam 809 at one end near the cam 809. As the rotating rod 701 rotates, the cam 809 can periodically squeeze the piston 806, causing the piston 806 to reciprocate within the compression cylinder 805, thereby realizing the function of automatically extracting and conveying flocculant.

[0030] A pump body 11 is fixedly installed at the bottom of the housing 1. The water inlet of the pump body 11 is connected to the mixing cylinder 2 through a pipe passing through the housing 1. The drain of the pump body 11 is connected to the purification cylinder 3 opposite to the direction of the liquid storage frame 810 through a pipe. The pump body 11 can quickly transport the backflow liquid mixed with flocculant in the mixing cylinder 2 to the corresponding purification cylinder 3 for filtration. A protective frame 12 is fixedly installed on the side of the housing 1 to protect the belt drive. The protective frame 12 can protect the belt drive part and prevent external debris from entering the belt drive system.

[0031] The working principle of the above embodiment is as follows: First, when purifying the backflow liquid, the operator puts the backflow liquid into the flow frame 9. During this process, larger particulate impurities in the backflow liquid are intercepted by the filter screen 10, while the backflow liquid entering the flow frame 9 flows into the purification cylinder 3 connected to the flow frame 9. Subsequently, an external motor drives the rotating column 801 to rotate, so that during the rotation of the rotating column 801, one of the rotating rods 701 can be driven to rotate via a belt, and again through the belt transmission, both rotating rods 701 rotate synchronously. During rotation, each rotating rod 701 can drive the corresponding cleaning auger 702 to move and clean the corresponding second filter plate 703. When the backflow liquid enters the purification cylinder 3 connected to the flow frame 9, it will be pushed to the second filter plate 703 by the cleaning auger 702. After being filtered by the second filter plate 703, it will flow into the mixing cylinder 2 through the connecting frame 4. During the movement, the cleaning auger 702 can push the impurities retained on the second filter plate 703 out of the purification cylinder 3, so that the second filter plate 703 maintains high-efficiency filtration performance.

[0032] The return liquid entering the mixing cylinder 2 will flow within the mixing cylinder 2 under the stirring of the stirring plate 802 driven by the rotating column 801. During rotation, the rotating column 801 drives the cam 809 to push the piston 806 to slide within the compression cylinder 805. As the piston 806 reciprocates within the compression cylinder 805, when the compression cylinder 805 is under negative pressure, the liquid flocculant in the storage frame 810 can enter the compression cylinder 805 through a pipe and the corresponding one-way valve 808. When the cam 809 squeezes the piston 806, the piston 806 compresses the spring 807 and pushes the flocculant within the compression cylinder 805, causing the flocculant to pass through another one-way valve 808. The solution is directed to valve 808, which discharges into discharge pipe 803 through a pipeline and sprays into mixing cylinder 2 through multiple nozzles 804. The stirring of stirring plate 802 causes flocculant to mix with backflow liquid to form flocculent material. Since stirring plate 802 is inclined, backflow liquid can flow axially along rotating column 801 during stirring, and drive flocculent material to the end of mixing cylinder 2. Then, pump body 11 draws flocculent material and backflow liquid from the end of mixing cylinder 2 and delivers them to purification cylinder 3 connected to discharge frame 5. After passing through first filter plate 6 and second filter plate 703, backflow liquid can be discharged through discharge frame 5, while flocculent material retained on first filter plate 6 can be pushed out of purification cylinder 3 by cleaning auger 702.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0034] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A drilling fracturing flowback fluid filtration and purification device, comprising a housing (1), characterized in that: The housing (1) is fixedly installed with a mixing cylinder (2) for mixing the backflow liquid and flocculant and two purification cylinders (3). One purification cylinder (3) is used to filter large impurities, while the other purification cylinder (3) is used to filter flocculents after mixing with flocculant. One end of each purification cylinder (3) passes through the housing (1). One purification cylinder (3) is fixedly connected to the mixing cylinder (2) with a connecting frame (4), while the circumferential surface of the other purification cylinder (3) is fixedly connected to an L-shaped discharge frame (5). One end of the discharge frame (5) passes through the housing (1), and a first filter plate (6) is installed on the inner wall of the discharge frame (5). Both purification cylinders (3) are equipped with filter discharge components (7) for discharging impurities. The mixing cylinder (2) is equipped with a mixing component (8) for mixing the backflow liquid with the flocculant.

2. The drilling fracturing flowback fluid filtration and purification device according to claim 1, characterized in that: The filter discharge assembly (7) includes a rotating rod (701) rotatably connected to the inner wall of the purification cylinder (3), a cleaning auger (702) fixedly connected to the circumferential surface of the rotating rod (701), and a second filter plate (703) fixedly installed on the circumferential surface of the purification cylinder (3). The second filter plate (703) has an arc-shaped structure, and the cleaning auger (702) and the second filter plate (703) are in contact with the inner wall of the purification cylinder (3).

3. The drilling fracturing flowback fluid filtration and purification device according to claim 2, characterized in that: One end of each of the two rotating rods (701) is connected to a pulley via a belt.

4. The drilling fracturing flowback fluid filtration and purification device according to claim 1, characterized in that: The inner wall of the housing (1) is fixedly connected to a conical flow frame (9), which is fixedly connected to one of the purification cylinders (3). A filter screen (10) is fixedly installed on the inner wall of the flow frame (9).

5. The drilling fracturing flowback fluid filtration and purification device according to claim 1, characterized in that: The mixing component (8) includes a rotating column (801) rotatably connected to the inner wall of the housing (1). One end of the rotating column (801) is connected to one of the rotating rods (701) via a belt and pulley. The rotating column (801) is rotatably connected to the mixing cylinder (2) via a sealed bearing. Multiple stirring plates (802) are fixedly connected to the circumferential surface of the rotating column (801). Each stirring plate (802) is inclined about the axis of the rotating column (801).

6. The drilling fracturing flowback fluid filtration and purification device according to claim 1, characterized in that: The mixing assembly (8) also includes a discharge pipe (803) fixedly installed on the inner wall of the mixing cylinder (2). The circumferential surface of the discharge pipe (803) is fixedly connected to a plurality of nozzles (804) distributed at equal distances along its axis. The inner wall of the housing (1) is fixedly installed with a compression cylinder (805). The inside of the compression cylinder (805) is slidably connected with a piston (806). A spring (807) is fixedly connected between the piston (806) and the compression cylinder (805). The circumferential surface of the compression cylinder (805) is fixedly connected to two one-way valves (808). The bottom end of the housing (1) is fixedly installed with a liquid storage frame (810). One side of the liquid storage frame (810) is fixedly connected to an inlet pipe (811). One end of the discharge pipe (803) is fixedly connected to one of the one-way valves (808) through a pipe. The bottom end of the liquid storage frame (810) is fixedly connected to the other one-way valve (808) through a pipe.

7. A drilling fracturing flowback fluid filtration and purification device according to claim 5 or 6, characterized in that: The hybrid assembly (8) also includes a cam (809) fixedly connected to the circumferential surface of a rotating rod (701), and the piston (806) is spherical at one end near the cam (809) and contacts the cam (809).

8. The drilling fracturing flowback fluid filtration and purification device according to claim 1, characterized in that: The bottom end of the housing (1) is fixedly installed with a pump body (11). The water inlet end of the pump body (11) is fixedly connected to the mixing cylinder (2) through the housing (1) via a pipe. The drain end of the pump body (11) is fixedly connected to the purification cylinder (3) opposite to the direction of the liquid storage frame (810) via a pipe.

9. The drilling fracturing flowback fluid filtration and purification device according to claim 1, characterized in that: A protective frame (12) is fixedly installed on the side of the housing (1).

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