CN117414727A - Preparation method and device for clean fracturing fluid - Google Patents

Abstract

The invention discloses a preparation method and a device of clean fracturing fluid, wherein the preparation device comprises a reaction kettle, a driving unit and a control unit, a mixing chamber, a screening chamber and a filter pressing chamber are sequentially arranged in the reaction kettle from top to bottom, a first-stage discharge port is arranged between the mixing chamber and the screening chamber, a second-stage discharge port is arranged between the screening chamber and the filter pressing chamber, a first electronic valve is arranged in the first-stage discharge port, a heating and stirring assembly is arranged in the mixing chamber, a screening assembly is arranged in the screening chamber, and a filter pressing assembly is arranged in the filter pressing chamber; the filter-pressing assembly is used for filtering part of insoluble impurities in the water-based fracturing fluid, discharging the filtered insoluble impurities out of the reaction kettle, and carrying out adsorption filtration on the residual insoluble impurities in the water-based fracturing fluid, so that the residue content in the water-based fracturing fluid can be reduced, clean fracturing fluid is prepared, and the permeability of a reservoir and the diversion capacity of cracks are improved.

Description

Preparation method and device for clean fracturing fluid

Technical field

The invention relates to a preparation method and device for clean fracturing fluid, belonging to the technical field of fracturing fluid preparation devices.

Background technique

Fracturing fluid plays the role of transmitting pressure and carrying proppant during fracturing construction. Currently, the fracturing fluid widely used at home and abroad is water-based fracturing fluid with natural vegetable gum as the thickener. Water-based fracturing fluid is made of It is composed of polymer thickener (vegetable gum, guar gum, coumarin gum, etc.), cross-linking agent, gel breaker, pH adjuster, bactericide, clay stabilizer and drainage aid, mostly cross-linked gel. The system, adding additives to help protect the formation, is relatively economical, suitable for continuous or batch mixing, suitable for oil wells, gas wells, water injection wells, and also suitable for sandstone or limestone formations; among them, plant gum fracturing liquids represented by guar gum derivatives It accounts for 90% of the entire fracturing fluid and has been playing an important role in improving oil and gas well recovery; however, the water-insoluble residue content of guanidine collagen powder is relatively large (about 19%-25%), and after the gel breaks The residue content is relatively high, which can reach 7%-10%. Therefore, during the preparation process of existing fracturing fluids, only the impurities in the reaction raw materials are filtered, and the residue content in the water-based fracturing fluid prepared is still relatively high. , which will lead to a decrease in reservoir permeability and fracture conductivity.

Contents of the invention

In view of this, the object of the present invention is to provide a preparation method and device for clean fracturing fluid to solve the technical problems mentioned in the prior art.

A preparation device for clean fracturing fluid, including:

Reaction kettle, the interior of the reaction kettle is provided with a mixing chamber, a screening chamber and a filter pressure chamber in order from top to bottom, and a first-level discharge port is provided between the mixing chamber and the screening chamber. , a secondary discharge port is provided between the screening chamber and the filter press chamber, and a first electronic valve is installed in the primary discharge port;

The mixing chamber is provided with a heating and stirring component. The heating and stirring component is used to heat and stir the reaction raw materials added to the mixing chamber, so that the reaction raw materials in the mixing chamber are fully mixed to obtain a water-based pressure. Crack the liquid and perform gel breaking reaction;

A screening assembly is provided in the screening chamber. The screening assembly is used to filter some insoluble impurities in the water-based fracturing fluid and discharge the filtered insoluble matter out of the reaction kettle. ;

A filter press component is provided in the filter press chamber, and a buffer tank is reserved at the bottom of the filter press component. The filter press component is used to adsorb and filter the remaining insoluble impurities in the water-based fracturing fluid. Obtain clean fracturing fluid, and pour the clean fracturing fluid into the buffer tank for storage;

A driving unit, the driving unit is used to drive the stirring assembly, the screening assembly and the filter press assembly to rotate synchronously;

A control unit, the control unit is respectively connected to the first electronic valve and the driving unit, and is used to control the opening and closing of the first electronic valve, and to control the starting and stopping of the driving unit.

Optionally, the heating stirring assembly includes:

Stirring rod, one end of the stirring rod penetrates the top of the mixing chamber and extends to the outside of the reaction kettle to be connected to the output end of the drive unit, and the other end of the stirring rod is connected to the mixing chamber The bottom end of the rotary connection;

A plurality of stirring blades, a plurality of stirring blades are evenly installed on the outer surface of the stirring rod in an annular shape, and the structure of each stirring blade is an arc-shaped filter plate;

A plurality of heating plates, which are evenly installed on the side walls of the mixing chamber, leaving a gap between the stirring blades and the heating plates during rotation;

A temperature sensor, the probe of which is installed at the bottom end of the mixing chamber;

The heating plate and the temperature sensor are respectively connected to the control unit.

Optionally, the screening components include:

A rotating shaft, one end of the rotating shaft passes through the top of the screening chamber and is connected to the stirring rod, and the other end of the rotating shaft is rotationally connected to the bottom end of the screening chamber;

Several conical filter cartridges are installed side by side in the screening chamber along the vertical direction, and the filter hole diameters of the several conical filter cartridges decrease in sequence from top to bottom, and each of the conical filter cartridges The open ends of the conical filter cylinder are all set downward, the middle part of the conical filter cylinder is sleeved on the outer surface of the rotating shaft, and the bottom end of the conical filter cylinder is installed in the screening chamber. on the side wall;

A waste recycling box, which is installed on the outer wall of the reactor;

A number of discharge openings are provided on the side wall of the screening chamber close to the bottom of the conical filter cartridge. Several of the discharge openings are respectively connected with the inside of the waste recycling box. The discharge openings The height is greater than the wall thickness of the conical filter cartridge, and the bottom end of the discharge port is flush with the bottom end of the conical filter cartridge;

A scraper is arranged parallel to the top side of each conical filter cartridge. One end of the scraper is installed on the outer surface of the rotating shaft, and the other end of the scraper is in contact with the conical filter cartridge. The side walls are slidingly connected; the scraper scrapes the filtered insoluble impurities on the surface of the conical filter cylinder into the discharge port, and discharges them from the discharge port into the waste recycling box;

A second electronic valve is installed at each discharge port, and the second electronic valve is connected to the control unit.

Optionally, the filter press assembly includes:

A bidirectional reciprocating screw rod. One end of the bidirectional reciprocating screw rod penetrates the top of the filter press chamber and is connected to the rotating shaft. The other end of the bidirectional reciprocating screw rod extends into the buffer groove and is connected with the buffer groove. The bottom end of the inner wall of the groove is rotationally connected;

A filter press plate, the top of the filter press plate is provided with a number of countersunk holes, and one-way membranes are respectively installed in several of the countersunk holes;

The filter press plate includes a first-stage filter press plate, a second-stage filter press plate and a third-stage filter press plate. The first-stage filter press plate, the second-stage filter press plate and the third-stage filter press plate are arranged from top to bottom. The following are arranged in the filter press chamber in sequence;

The threads of the first-stage filter press plate are installed on the outer surface of the two-way reciprocating screw rod, and the reciprocating movement range of the first-stage filter press plate is set between the top of the filter press chamber and the second-stage filter press. Between the plates, the outer surface of the first-stage filter press plate is slidingly connected to the side wall of the filter press chamber, and the first-stage filter press plate is provided with a limited hole near the side wall of the filter press chamber, so A limit rod is installed in the limit hole, one end of the limit rod is connected to the top of the filter press chamber, and the other end of the limit rod is connected to the top of the secondary filter press plate;

The two-stage filter press plate and the three-stage filter press plate are respectively sleeved on the outer surface of the two-way reciprocating screw rod, and the outer surfaces of the two-stage filter press plate and the three-stage filter press plate are installed respectively. On the side wall of the filter press chamber, an adsorption layer is filled between the opposite surfaces of the secondary filter press plate and the third-stage filter press plate.

Optionally, the one-way membrane is a cone-shaped rubber sleeve, the cone-shaped rubber sleeve is installed in the countersunk hole, and the open end of the cone-shaped rubber sleeve faces the top side of the filter press plate;

When the conical rubber sleeve is not subjected to downward extrusion force, the bottom end of the conical rubber sleeve is in a closed state;

When the conical rubber sleeve is subjected to downward extrusion force, the bottom end of the conical rubber sleeve is in an open state.

Optionally, the top of the reaction kettle is provided with a feeding port and a water injection port, and the feeding port and the water injection port are respectively connected with the mixing chamber;

The bottom end of the reaction kettle is provided with a three-stage discharge port and a sewage discharge port. The three-stage discharge port and the sewage discharge port are respectively connected with the bottom end of the side wall of the buffer tank. The three-stage discharge port A third electronic valve is installed, and the sewage outlet is installed with a fourth electronic valve. The third electronic valve and the fourth electronic valve are respectively connected to the control unit.

A method for preparing clean fracturing fluid, using the above-mentioned preparation device to prepare clean fracturing fluid, including the following steps:

Step 1) Add reaction raw materials into the mixing chamber to prepare water-based fracturing fluid, and perform gel breaking treatment on the water-based fracturing fluid;

Step 2) After the water-based fracturing fluid undergoes gel breaking treatment, the control unit controls the first electronic valve to open the first-level discharge port, so that the water-based fracturing fluid after gel breaking treatment flows into the screening chamber. In the room, the water-based fracturing fluid after gel breaking treatment is screened and filtered through a screening component;

Step 3) The water-based fracturing fluid that has been screened and filtered flows into the filtration chamber from the second outlet, and is filtered and adsorbed through the filtration assembly to obtain clean fracturing fluid.

Optionally, in step 1), after the addition of reaction raw materials in the mixing chamber is completed, the control unit controls the driving unit to start, and controls the heating plate to heat the inside of the mixing chamber, so that the driving unit controls the rotation of the stirring rod. , and drive the stirring blade to stir the reaction raw materials inside the mixing chamber, so that the reaction raw materials are fully mixed to obtain a water-based fracturing fluid. After the water-based fracturing fluid reaches the preset temperature value, a gel breaking reaction occurs with the gel breaker. , and at the same time, the temperature sensor is used to detect the temperature of the water-based fracturing fluid in the mixing chamber, until the temperature sensor detects that the temperature value of the water-based fracturing fluid reaches the preset temperature value, and sends the detection information to the control unit, so that the The control unit controls the heating plate to stop heating.

Optionally, in step 2), after the control unit controls the heating plate to stop heating, it delays for at least 30 seconds before controlling the first electronic valve to open, so that after the water-based fracturing fluid is completely broken, the The first-level discharge port flows into the screening chamber, and sequentially passes through multiple conical filter cylinders to filter some insoluble impurities in the water-based fracturing fluid, and at the same time, each part is filtered through the corresponding scraper. 1. scraping off the filtered insoluble impurities on the surface of the conical filter cylinder;

After the water-based fracturing fluid inside the mixing chamber is completely discharged, the control unit controls the first electronic valve to close and the second electronic valve to open, so that the scraper moves the conical filter cartridge under the action of centrifugal force. The insoluble impurities on the surface are thrown out from the discharge port into the waste recycling box, and the second electronic valve is closed until the first electronic valve is opened next time.

Optionally, in step three), after the water-based fracturing fluid flows into the filter press chamber from the second outlet, the bidirectional reciprocating screw drives the first-stage filter press plate to reciprocate up and down to squeeze the filter press chamber. The water-based fracturing fluid;

When the first-stage filter press plate squeezes the water-based fracturing fluid upward, part of the water-based fracturing fluid pushes away the unidirectional membrane on the first-stage filter press plate and flows to the first-stage press plate. Between the filter plate and the secondary filter press plate;

When the first-stage filter press plate squeezes the water-based fracturing fluid downward, the water-based fracturing fluid between the first-stage filter press plate and the second-stage filter press plate is pressed into Between the second-stage filter press plate and the third-stage filter press plate, and after adsorption and filtration by the adsorption layer, the one-way membrane on the third-stage filter press plate is pushed open and flows into the buffer tank.

The beneficial effects produced by this invention include:

The preparation device for clean fracturing fluid provided by the present invention, by setting up a mixing chamber, a screening chamber and a filter pressure chamber, can filter the water-based fracturing fluid immediately after gel breaking treatment to avoid water-based fracturing fluid. After the fracturing fluid is cooled, the viscosity increases, making it difficult to separate impurities; at the same time, through the screening component, some insoluble impurities in the water-based fracturing fluid can be filtered, and the filtered insoluble impurities can be discharged out of the reactor, thereby Reduce the residue content in the water-based fracturing fluid; and by setting up a filter press component, the remaining insoluble impurities in the water-based fracturing fluid can be adsorbed and filtered to further reduce the residue content in the water-based fracturing fluid to prepare clean Fracturing fluid improves reservoir permeability and fracture conductivity.

Description of the drawings

Figure 1 is a schematic structural diagram of a preparation device for clean fracturing fluid according to the present invention;

Figure 2 is a cross-sectional view along line A-A of Figure 1 in the present invention;

Figure 3 is a sectional view taken along line B-B of Figure 1 in the present invention;

Figure 4 is an enlarged view of C in Figure 2 according to the present invention;

Figure 5 is a schematic flow chart of a preparation method of clean fracturing fluid according to the present invention;

In the picture: 1. Reactor; 2. Mixing chamber; 3. Screening chamber; 4. Press filter chamber; 5. Primary discharge port; 6. Secondary discharge port; 7. First electronic valve ; 8. Buffer tank; 9. Drive unit; 10. Stirring rod; 11. Stirring blade; 12. Heating plate; 13. Temperature sensor; 14. Rotating shaft; 15. Conical filter cartridge; 16. Waste recycling box; 17. Discharge port; 18. Scraper; 19. Second electronic valve; 20. Bidirectional reciprocating screw; 21. Primary filter press plate; 22. Secondary filter press plate; 23. Third-stage filter press plate; 24. Sinking Head hole; 25. One-way membrane; 26. Limiting rod; 27. Adsorption layer; 28. Feeding port; 29. Water injection port; 30. Third-level outlet; 31. Sewage outlet; 32. Third electronic valve; 33. The fourth electronic valve.

Detailed ways

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

Embodiment 1;

As shown in Figures 1-4, the present invention provides a preparation device for clean fracturing fluid, including:

Reactor 1. The interior of the reactor 1 is provided with a mixing chamber 2, a screening chamber 3 and a filter pressure chamber 4 in order from top to bottom. There is a first-level discharge between the mixing chamber 2 and the screening chamber 3. Port 5, a secondary discharge port 6 is provided between the screening chamber 3 and the filter pressure chamber 4, and a first electronic valve 7 is installed in the primary discharge port 5;

A heating and stirring component is installed in the mixing chamber 2. The heating and stirring component is used to heat and stir the reaction raw materials added to the mixing chamber 2. The reaction raw materials include guar gum powder, cross-linking agent, gel breaker, and pH value adjustment. agent, bactericide, clay stabilizer, drainage aid and water, so that the reaction raw materials in the mixing chamber 2 are fully mixed to obtain a water-based fracturing fluid, and after heating the water-based fracturing fluid to 70°C, the gel is broken The agent gradually dissolves and releases acidic substances to perform a gel breaking reaction on the water-based fracturing fluid;

A screening assembly is installed in the screening chamber 3. The screening assembly is used to filter some insoluble impurities in the water-based fracturing fluid and discharge the filtered insoluble impurities to the outside of the reaction kettle 1 for processing. Insoluble impurities in the water-based fracturing fluid undergo one-stage filtration to reduce the residue content in the water-based fracturing fluid, thereby improving reservoir permeability and fracture conductivity;

A filter press assembly is installed in the filter press chamber 4. A buffer tank 8 is reserved at the bottom of the filter press assembly. The filter press assembly is used to adsorb and filter the remaining insoluble impurities in the water-based fracturing fluid to further reduce the water-based pressure. The residue content in the fracturing fluid is obtained to obtain clean fracturing fluid, which improves the reservoir permeability and fracture conductivity, and the clean fracturing fluid is poured into the buffer tank 8 for storage;

Driving unit 9, the driving unit 9 is used to drive the stirring assembly, screening assembly and filter press assembly to rotate synchronously;

The control unit is connected to the first electronic valve 7 and the driving unit 9 respectively, and is used to control the opening and closing of the first electronic valve 7 and the starting and stopping of the driving unit 9.

It should be noted that: in order to facilitate the judgment of the internal working status of the mixing chamber 2, the screening chamber 3 and the filter pressure chamber 4, an observation window is set outside the reaction kettle 1 and located in the middle and lower part of each chamber; at the same time In order to facilitate the automatic detection of whether the water-based fracturing fluid inside the mixing chamber 2 is completely discharged, a liquid level switch can be installed at the bottom of the mixing chamber 2, and the liquid level switch is connected to the control unit, so that the control unit can act according to the position of the liquid level switch. The liquid level detection information controls the opening and closing of the first electronic valve 7 .

As another embodiment of the present invention, the prepared water-based fracturing fluid and gel breaker can be directly added into the mixing chamber 2 for gel breaking treatment, and then the water-based fracturing fluid after gel breaking treatment can be The insoluble impurities contained in it are sequentially screened, filtered and adsorbed to obtain clean fracturing fluid, which can improve the preparation efficiency of clean fracturing fluid and is suitable for large-scale oil well mining construction.

Further, the heating stirring assembly includes:

Stirring rod 10, one end of the stirring rod 10 penetrates the top of the mixing chamber 2, and extends to the outside of the reactor 1 to be connected to the output end of the drive unit 9. The other end of the stirring rod 10 is rotationally connected to the bottom end of the mixing chamber 2. , in which the drive unit 9 adopts a reducer, which is installed on the top of the reactor 1 through a frame;

A number of stirring blades 11 are evenly welded to the outer surface of the stirring rod 10 in an annular shape. The structure of each stirring blade 11 is an arc-shaped filter plate. During the stirring process, through the filter holes on the arc-shaped filter plate, It helps to break up the reaction raw materials that appear to be agglomerated in the water, thereby accelerating the dissolution of the guar gum powder in the water and avoiding the agglomeration of the guar gum powder after it is added to the water;

Several heating plates 12 are evenly welded on the side walls of the mixing chamber 2, so that when the stirring blades 11 stir the reactants inside the mixing chamber 2, the heating plates 12 can provide resistance to the reactants, thereby Increase the disturbance intensity of the stirring blade 11 to the reactants and improve the mixing efficiency. At the same time, there is a gap between the stirring blade 11 and the heating plate 12 during the rotation process, which can prevent the mixing between the stirring blade 11 and the heating plate 12 during the rotation process. collision;

The temperature sensor 13, the temperature sensor 13 and the heating plate 12 are respectively connected to the control unit. The probe of the temperature sensor 13 is installed at the bottom end of the mixing chamber 2 for detecting the temperature of the reactants in the mixing chamber 2 and detecting the temperature. The temperature information is sent to the control unit, so that the control unit controls the heating plate 12 to heat the reactants in the mixing chamber 2 according to the temperature information.

Further, the screening components include:

Rotating shaft 14, one end of the rotating shaft 14 passes through the top of the screening chamber 3 and is welded to the bottom end of the stirring rod 10, and the other end of the rotating shaft 14 is rotationally connected to the bottom end of the screening chamber 3 through a bearing;

Several conical filter cylinders 15 are installed side by side in the screening chamber 3 along the vertical direction, and the filter hole diameters of the several conical filter cylinders 15 decrease in sequence from top to bottom. The open ends of the cylinder 15 are all arranged downward, the middle part of the conical filter cylinder 15 is sleeved on the outer surface of the rotating shaft 14, and the bottom end side of the conical filter cylinder 15 is fixedly installed on the side wall of the screening chamber 3. It is used for multi-stage filtration of insoluble impurities in the water-based fracturing fluid after gel breaking treatment;

The waste recycling box 16 is welded on the outer wall of the reactor 1 and is used to collect filtered insoluble impurities. At the same time, in order to facilitate the cleaning of the impurities accumulated inside the waste recycling box 16, there is a A conical discharge port is provided at the bottom, and a valve plate is installed at the bottom of the conical discharge port for regularly cleaning insoluble impurities inside the waste recycling box 16;

A number of discharge openings 17 are provided on the side wall of the screening chamber 3 close to the bottom of the conical filter cylinder 15. The several discharge openings 17 are respectively connected with the inside of the waste recycling box 16. The height of the discharge openings 17 is larger than that of the conical filter cartridge 15. The wall thickness of the cone-shaped filter cartridge 15 is such that the bottom end of the discharge port 17 is flush with the bottom end of the cone-shaped filter cartridge 15. A scraper 18 is arranged parallel to the top side of each cone-shaped filter cartridge 15. The scraper 18 One end is fixedly installed on the outer surface of the rotating shaft 14, and the other end of the scraper 18 is slidingly connected to the side wall of the conical filter cylinder 15, so that during the rotation of the rotating shaft 14, the scraper 18 is driven to filter the surface of the conical filter cylinder 15. The insoluble impurities are scraped into the discharge port 17 and thrown out from the discharge port 17 into the waste recycling box 16 to realize automatic cleaning of insoluble impurities;

A second electronic valve 19 is installed at each discharge port 17. The second electronic valve 19 is connected to the control unit. The second electronic valve 19 is closed before the first electronic valve 7 is opened to prevent the scraper 18 from centrifugal force. The water-based fracturing fluid is brought into the waste recovery box 16 from the discharge port 17 .

Further, the filter press assembly includes:

Bidirectional reciprocating screw rod 20. One end of the bidirectional reciprocating screw rod 20 penetrates the top of the filter press chamber 4 and is welded to the bottom end of the rotating shaft 14. The other end of the bidirectional reciprocating screw rod 20 extends into the buffer tank 8 and is connected with the buffer tank 8. The bottom end of the inner wall is rotationally connected through a bearing;

The filter press plate has a number of countersunk holes 24 at the top, and one-way membranes 25 are respectively installed in the countersunk holes 24; wherein, the filter press plate includes a primary filter press plate 21 and a secondary filter press plate 22. and a three-stage filter press plate 23. The first-stage filter press plate 21, the second-stage filter press plate 22 and the third-stage filter press plate 23 are installed in the filter press chamber 4 in sequence from top to bottom.

Specifically, the primary filter press plate 21 is threadedly installed on the outer surface of the bidirectional reciprocating screw rod 20, and the reciprocating movement range of the primary filter press plate 21 is set between the top of the filter press chamber 4 and the secondary filter press plate 22. During this period, the outer surface of the first-stage filter press plate 21 is slidingly connected to the side wall of the filter press chamber 4. A limited hole is provided in the first-stage filter press plate 21 close to the side wall of the filter press chamber 4. There is a limited sliding installation in the limit hole. Position rod 26, one end of the limit rod 26 is fixedly connected to the top of the filter press chamber 4, and the other end of the limit rod 26 is fixedly connected to the top of the secondary filter press plate 22; the second-stage filter plate 22 and the third-stage filter The filter plates 23 are respectively sleeved on the outer surface of the bidirectional reciprocating screw rod 20. The outer surfaces of the secondary filter press plate 22 and the third-stage filter press plate 23 are respectively fixedly installed on the side walls of the filter press chamber 4. The opposite surfaces of the filter plate 22 and the third-stage filter press plate 23 are filled with an adsorption layer 27; during use of the filter press assembly, when the water-based fracturing fluid flows from the secondary outlet 6 into the filter press chamber 4 Finally, the bidirectional reciprocating screw rod 20 drives the primary filter plate 21 to reciprocate up and down to squeeze the water-based fracturing fluid; wherein, when the primary filter plate 21 squeezes the water-based fracturing fluid upward, part of the water-based fracturing fluid is After being squeezed into contact with the top of the filter chamber 4, the water-based fracturing fluid pushes away the one-way membrane 25 on the primary filter plate 21 and flows toward the primary filter plate 21 and the secondary filter plate 21. between the filter press plates 22; then, when the primary filter press plate 21 squeezes the water-based fracturing fluid downward, the water-based fracturing fluid between the primary filter press plate 21 and the secondary filter press plate 22 , is pressed between the secondary filter press plate 22 and the third-stage filter press plate 23, and after adsorbing and filtering the insoluble impurities in the water-based fracturing fluid through the adsorption layer 27, a clean fracturing fluid is obtained, and the clean fracturing fluid is Under the continuous pressure of the first-stage filter press plate 21, the cracking liquid pushes open the one-way membrane 25 on the third-stage filter press plate 23 and flows into the buffer tank 8.

It should be noted that in this embodiment, in order to eliminate the pressure difference formed in the chambers on the upper and lower sides of the first-stage filter press plate 21 during its up and down reciprocating movement, causing back suction and affecting the normal use of the one-way membrane 25, the The limit rod 26 is set as a hollow rod, and a number of ventilation holes are provided on the side walls of the limit rod 26 to connect the chambers on both sides of the first-stage filter plate 21; at the same time, in order to facilitate the subsequent adjustment of the limit rod 26 for maintenance, and fix and install the two ends of the limit rod 26 with bolts and other fasteners.

As a specific implementation mode of the present invention, the adsorption layer 27 in this embodiment adopts a honeycomb sandwich structure composed of activated carbon fibers. The sandwich layer is provided with at least three layers, and a steel structure skeleton is used to fix the two adjacent layers. The steel structure skeleton is sprayed with a corrosion-resistant coating.

Further, the one-way membrane 25 is a conical rubber sleeve. The conical rubber sleeve is installed in the countersunk hole 24. The open end of the conical rubber sleeve faces the top side of the filter press plate; when the conical rubber sleeve is not subjected to downward pressure, When the cone-shaped rubber sleeve is subjected to downward extrusion force, the bottom end of the cone-shaped rubber sleeve is in a closed state; when the cone-shaped rubber sleeve is subjected to downward extrusion force, the bottom end of the cone-shaped rubber sleeve is in an open state.

Further, the top of the reaction kettle 1 is provided with a feeding port 28 and a water injection port 29. The feeding port 28 and the water injection port 29 are respectively connected with the mixing chamber 2 to facilitate the addition of reaction raw materials through the feeding port 28 and the addition of water through the water injection port 29; The bottom end of the reaction kettle 1 is provided with a third-level discharge port 30 and a sewage discharge port 31. The third-level discharge port 30 and the sewage discharge port 31 are respectively connected with the bottom end of the side wall of the buffer tank 8. The third-level discharge port 30 is equipped with a third-level discharge port 30 and a sewage discharge port 31. There are three electronic valves 32, and a fourth electronic valve 33 is installed on the sewage outlet 31. The third electronic valve 32 and the fourth electronic valve 33 are respectively connected to the control unit for controlling the opening and closing of the third electronic valve 32 and the fourth electronic valve 33. .

Specifically, during use of the preparation device, the feed end of the fracturing fluid transportation pipeline is installed on the third-stage outlet 30, and the sewage outlet 31 is connected to the sedimentation tank through the sewage pipeline; wherein, when cleaning the fracturing fluid After the preparation is completed, the control unit opens the third electronic valve 32 to send the clean fracturing fluid into the fracturing fluid delivery pipeline. At the same time, in order to allow the clean fracturing fluid to flow out of the buffer tank 8 quickly, a delivery valve can be added to the fracturing fluid delivery pipeline. Pump; when the use of the preparation device is finished, or the internal adsorption layer 27 and the filter port are clogged, resulting in a reduction in the preparation efficiency of clean fracturing fluid and the need for cleaning, stop adding materials, and then close the second electronic valve 19 through the control unit and the third electronic valve 32, and open the first electronic valve 7 and the fourth electronic valve 33, then continue to inject water into the mixing chamber 2, and start the driving unit 9, so that the mixing blades 11 have not completely drained the mixing chamber 2 The water-based fracturing fluid is diluted to reduce the viscosity; at the same time, the scraper 18 uses the diluted water-based fracturing fluid to scrape off impurities on the surface of the conical filter cartridge 15, thereby accelerating the dilution of the water-based fracturing fluid from The filter holes pass through; and, under the reciprocating extrusion of the first-stage filter plate 21, the diluted water-based fracturing fluid is continuously injected into the adsorption layer 27, the surface of the adsorption layer 27 is washed, and then the washed waste is The liquid is discharged into the sedimentation tank through the sewage outlet 31 and the sewage pipe until the water discharge speed of the sewage pipe remains unobstructed, and finally the clarified liquid after sedimentation in the sedimentation tank is recycled.

Embodiment 2;

As shown in Figure 5, the present invention also provides a method for preparing clean fracturing fluid. The above-mentioned preparation device is used to prepare clean fracturing fluid, which includes the following steps:

Step 1) Add reaction raw materials into the mixing chamber 2 to prepare water-based fracturing fluid, and perform gel breaking treatment on the water-based fracturing fluid.

Specifically, when the addition of reaction raw materials into the mixing chamber 2 is completed, the control unit controls the driving unit 9 to start, and controls the heating plate 12 to heat the inside of the mixing chamber 2, so that the driving unit 9 controls the rotation of the stirring rod 10 and drives the stirring. The blade 11 stirs the reaction raw materials inside the mixing chamber 2, so that the reaction raw materials are fully mixed to obtain a water-based fracturing fluid. After the water-based fracturing fluid reaches the preset temperature value, a gel breaking reaction occurs with the gel breaker, and at the same time, the temperature The sensor 13 detects the temperature of the water-based fracturing fluid in the mixing chamber 2 until the temperature sensor 13 detects that the temperature value of the water-based fracturing fluid reaches a preset temperature value, and sends the detection information to the control unit, so that the control unit controls the heating. Plate 12 stops heating.

Step 2) After the water-based fracturing fluid undergoes gel breaking treatment, the control unit controls the first electronic valve 7 to open the primary discharge port 5 so that the water-based fracturing fluid after gel breaking treatment flows into the screening chamber 3 inside, and the water-based fracturing fluid after gel breaking treatment is screened and filtered through the screening component.

Specifically, after the control unit controls the heating plate 12 to stop heating, it delays for at least 30 seconds before controlling the first electronic valve 7 to open, so that after the water-based fracturing fluid is completely gel-breaking, it flows from the primary outlet 5 into the screening chamber. In the chamber 3, some insoluble impurities in the water-based fracturing fluid are filtered through multiple conical filter cylinders 15 in sequence, and at the same time, the filtered insoluble matter on the surface of each conical filter cylinder 15 is filtered through the corresponding scraper 18. Impurities are scraped off;

After the water-based fracturing fluid inside the mixing chamber 2 is completely discharged, the control unit controls the first electronic valve 7 to close and the second electronic valve 19 to open, so that the scraper 18 moves the surface of the conical filter cartridge 15 under the action of centrifugal force. The insoluble impurities are thrown out from the discharge port 17 into the waste recovery box 16, and the second electronic valve 19 is closed until the first electronic valve 7 is opened next time.

Step 3) The water-based fracturing fluid that has been screened and filtered flows into the filter pressure chamber 4 from the second outlet, and is filtered and adsorbed through the filter press assembly to obtain clean fracturing fluid.

Specifically, after the water-based fracturing fluid flows into the filter press chamber 4 from the second outlet, the bidirectional reciprocating screw 20 drives the primary filter plate 21 to reciprocate up and down to squeeze the water-based fracturing fluid;

When the primary filter press plate 21 squeezes the water-based fracturing fluid upward, part of the water-based fracturing fluid pushes open the one-way filter membrane on the primary filter press plate 21 and flows to the primary filter press plate 21 and the secondary pressure fracturing fluid. between filter plates 22;

When the primary filter press plate 21 squeezes the water-based fracturing fluid downward, the water-based fracturing fluid between the primary filter press plate 21 and the secondary filter press plate 22 is pressed into the secondary filter press plate 22 and the three-stage filter press plate 23, and after adsorption and filtration by the adsorption layer 27, the one-way membrane 25 on the three-stage filter press plate 23 is pushed open, and flows into the buffer tank 8.

The above are only a few embodiments of the present invention, and are not intended to limit the present invention in any way. Although the present invention is disclosed above in preferred embodiments, it is not intended to limit the present invention. Any person familiar with the art, Without departing from the scope of the technical solution of the present invention, slight changes or modifications made using the technical content disclosed above are equivalent to equivalent implementation examples and fall within the scope of the technical solution.

Claims (10)

1. A device for preparing a clean fracturing fluid, comprising:

the reaction kettle (1), the inside of the reaction kettle (1) is provided with a mixing chamber (2), a screening chamber (3) and a filter pressing chamber (4) from top to bottom in sequence, a first-stage discharge port (5) is arranged between the mixing chamber (2) and the screening chamber (3), a second-stage discharge port (6) is arranged between the screening chamber (3) and the filter pressing chamber (4), and a first electronic valve (7) is arranged in the first-stage discharge port (5);

the mixing chamber (2) is internally provided with a heating and stirring assembly, and the heating and stirring assembly is used for heating and stirring the reaction raw materials added into the mixing chamber (2) so that the reaction raw materials in the mixing chamber (2) are fully mixed to obtain water-based fracturing fluid and carry out gel breaking reaction;

a screening component is arranged in the screening cavity (3) and is used for filtering part of insoluble impurities in the water-based fracturing fluid and discharging the filtered insoluble impurities out of the reaction kettle (1);

a filter pressing assembly is arranged in the filter pressing chamber (4), a buffer groove (8) is reserved at the bottom of the filter pressing assembly, the filter pressing assembly is used for adsorbing and filtering residual insoluble impurities in the water-based fracturing fluid to obtain clean fracturing fluid, and the clean fracturing fluid is pressed into the buffer groove (8) for storage;

the driving unit (9) is used for driving the stirring assembly, the screening assembly and the filter pressing assembly to synchronously rotate;

the control unit is respectively connected with the first electronic valve (7) and the driving unit (9) and is used for controlling the opening and closing of the first electronic valve (7) and controlling the starting and stopping of the driving unit (9).

2. The apparatus for preparing a clean fracturing fluid according to claim 1, wherein said heating and stirring assembly comprises:

one end of the stirring rod (10) penetrates through the top end of the mixing chamber (2) and extends to the outer side of the reaction kettle (1) to be connected with the output end of the driving unit (9), and the other end of the stirring rod (10) is rotationally connected with the bottom end of the mixing chamber (2);

a plurality of stirring blades (11), wherein the stirring blades (11) are annularly and uniformly arranged on the outer surface of the stirring rod (10), and each stirring blade (11) has an arc-shaped filter plate;

a plurality of heating plates (12), wherein the heating plates (12) are uniformly arranged on the side wall of the mixing chamber (2), and a gap is reserved between the stirring blades (11) and the heating plates (12) in the rotating process;

a temperature sensor (13), wherein a probe of the temperature sensor (13) is arranged at the bottom end of the mixing chamber (2);

the heating plate (12) and the temperature sensor (13) are respectively connected with the control unit.

3. The apparatus for preparing a clean fracturing fluid according to claim 2, wherein said screen assembly comprises:

the rotating shaft (14), one end of the rotating shaft (14) penetrates through the top end of the screening cavity (3) and is connected with the stirring rod (10), and the other end of the rotating shaft (14) is rotationally connected with the bottom end of the screening cavity (3);

the conical filter cartridges (15) are arranged in the screening cavity (3) in parallel along the vertical direction, the pore diameters of the filter holes of the conical filter cartridges (15) are gradually decreased from top to bottom, the opening end of each conical filter cartridge (15) is arranged downwards, the middle part of each conical filter cartridge (15) is sleeved on the outer surface of the rotating shaft (14), and one side of the bottom end of each conical filter cartridge (15) is arranged on the side wall of the screening cavity (3);

the waste recycling box (16), the waste recycling box (16) is installed on the outer side wall of the reaction kettle (1);

a plurality of discharge ports (17) are formed in one side, close to the bottom of the conical filter cylinder (15), of the side wall of the screening cavity (3), the discharge ports (17) are respectively communicated with the inside of the waste recycling bin (16), the height of each discharge port (17) is larger than the wall thickness of the conical filter cylinder (15), and the bottom end of each discharge port (17) is flush with the bottom end of the conical filter cylinder (15);

a scraping plate (18) is arranged on one side of the top end of each conical filter cylinder (15) in parallel, one end of each scraping plate (18) is arranged on the outer surface of the rotating shaft (14), and the other end of each scraping plate (18) is in sliding connection with the side wall of each conical filter cylinder (15); the scraping plate (18) scrapes insoluble impurities filtered on the surface of the conical filter cylinder (15) into the discharge port (17) and discharges the insoluble impurities into the waste recycling bin (16) from the discharge port (17);

and each discharge hole (17) is provided with a second electronic valve (19), and the second electronic valves (19) are connected with the control unit.

4. A device for preparing a clean fracturing fluid according to claim 3, wherein said press assembly comprises:

one end of the bidirectional reciprocating screw rod (20) penetrates through the top end of the filter pressing cavity (4) to be connected with the rotating shaft (14), and the other end of the bidirectional reciprocating screw rod (20) extends into the buffer groove (8) and is rotationally connected with the bottom end of the inner wall of the buffer groove (8);

a plurality of counter sunk holes (24) are formed in the top end of the filter pressing plate, and unidirectional films (25) are respectively arranged in the counter sunk holes (24);

the filter pressing plate comprises a primary filter pressing plate (21), a secondary filter pressing plate (22) and a tertiary filter pressing plate (23), wherein the primary filter pressing plate (21), the secondary filter pressing plate (22) and the tertiary filter pressing plate (23) are sequentially arranged in the filter pressing chamber (4) from top to bottom;

the primary filter press plate (21) is arranged on the outer surface of the bidirectional reciprocating screw rod (20) in a threaded manner, the reciprocating movement range of the primary filter press plate (21) is arranged between the top end of the filter press chamber (4) and the secondary filter press plate (22), the outer surface of the primary filter press plate (21) is in sliding connection with the side wall of the filter press chamber (4), a limiting hole is formed in the position, close to the side wall of the filter press chamber (4), of the primary filter press plate (21), a limiting rod (26) is arranged in the limiting hole, one end of the limiting rod (26) is connected with the top end of the filter press chamber (4), and the other end of the limiting rod (26) is connected with the top end of the secondary filter press plate (22);

the secondary filter press plate (22) and the tertiary filter press plate (23) are respectively sleeved on the outer surface of the bidirectional reciprocating screw rod (20), the outer surfaces of the secondary filter press plate (22) and the tertiary filter press plate (23) are respectively installed on the side wall of the filter press chamber (4), and an adsorption layer (27) is filled between the opposite surfaces of the secondary filter press plate (22) and the tertiary filter press plate (23).

5. The preparation device of the clean fracturing fluid according to claim 4, wherein the unidirectional membrane (25) is a conical rubber sleeve, the conical rubber sleeve is arranged in the counter bore (24), and the open end of the conical rubber sleeve faces to the top end side of the filter pressing plate;

when the conical rubber sleeve is not subjected to downward extrusion force, the bottom end of the conical rubber sleeve is in a closed state;

when the conical rubber sleeve is subjected to downward extrusion force, the bottom end of the conical rubber sleeve is in an open state.

6. The preparation device of the clean fracturing fluid according to claim 1, wherein a feed port (28) and a water injection port (29) are arranged at the top end of the reaction kettle (1), and the feed port (28) and the water injection port (29) are respectively communicated with the mixing chamber (2);

the bottom of reation kettle (1) is provided with tertiary discharge gate (30) and drain (31), tertiary discharge gate (30) with drain (31) respectively with lateral wall bottom intercommunication of buffer tank (8), third electronic valve (32) are installed to tertiary discharge gate (30), fourth electronic valve (33) are installed to drain (31), third electronic valve (32) with fourth electronic valve (33) are connected with the control unit respectively.

7. A method for preparing a clean fracturing fluid, characterized in that the clean fracturing fluid is prepared by using the preparation device of any one of claims 1 to 6, and comprises the following steps:

step one), adding reaction raw materials into a mixing chamber (2) to prepare a water-based fracturing fluid, and carrying out gel breaking treatment on the water-based fracturing fluid;

step two), after the water-based fracturing fluid is subjected to gel breaking treatment, a control unit controls a first electronic valve (7) to open a first-stage discharge hole (5) so that the water-based fracturing fluid subjected to gel breaking treatment flows into a screening cavity (3), and the water-based fracturing fluid subjected to gel breaking treatment is screened and filtered through a screening component;

and step three), the water-based fracturing fluid subjected to screening and filtering treatment flows into a filter pressing chamber (4) from a second discharge hole, and filter pressing adsorption treatment is carried out through a filter pressing assembly, so that clean fracturing fluid is obtained.

8. The method for preparing the clean fracturing fluid according to claim 7, wherein in the first step), after the reaction raw materials are added into the mixing chamber, the control unit controls the driving unit (9) to start, controls the heating plate (12) to heat the inside of the mixing chamber (2), enables the driving unit (9) to control the stirring rod (10) to rotate, drives the stirring blade (11) to stir the reaction raw materials in the mixing chamber (2), enables the reaction raw materials to be fully mixed to obtain the water-based fracturing fluid, enables the water-based fracturing fluid to undergo a gel breaking reaction with a gel breaker after reaching a preset temperature value, detects the temperature of the water-based fracturing fluid in the mixing chamber (2) through the temperature sensor (13), and sends detection information to the control unit until the temperature sensor (13) detects that the temperature value of the water-based fracturing fluid reaches the preset temperature value, and enables the control unit to control the heating plate (12) to stop heating.

9. The method for preparing a clean fracturing fluid according to claim 7, wherein in the second step), after the control unit controls the heating plate (12) to stop heating, at least 30 seconds later, the first electronic valve (7) is controlled to be opened again, so that after the water-based fracturing fluid is completely broken, the water-based fracturing fluid flows into the sieving chamber (3) from the first-stage discharging port (5) and is filtered by a plurality of conical filter cartridges (15) in sequence, and meanwhile, the insoluble impurities filtered by the surface of each conical filter cartridge (15) are scraped by corresponding scrapers (18);

after the water-based fracturing fluid in the mixing chamber (2) is completely discharged, the control unit controls the first electronic valve (7) to be closed, and controls the second electronic valve (19) to be opened, so that the scraping plate (18) throws insoluble impurities on the surface of the conical filter cylinder (15) out of the discharge port (17) into the waste recovery tank (16) under the action of centrifugal force, and the second electronic valve (19) is closed until the first electronic valve (7) is opened next time.

10. The method for preparing the clean fracturing fluid according to claim 7, wherein in the third step), after the water-based fracturing fluid flows into the filter pressing chamber (4) from the second discharge port, the two-way reciprocating screw rod (20) drives the primary filter pressing plate (21) to reciprocate up and down to squeeze the water-based fracturing fluid;

when the primary filter press plate (21) upwards extrudes the water-based fracturing fluid, part of the water-based fracturing fluid pushes up a one-way film (25) on the primary filter press plate (21) and flows between the primary filter press plate (21) and the secondary filter press plate (22);

when the primary filter press plate (21) downwards extrudes the water-based fracturing fluid, the water-based fracturing fluid between the primary filter press plate (21) and the secondary filter press plate (22) is pressed between the secondary filter press plate (22) and the tertiary filter press plate (23), and after being adsorbed and filtered by the adsorption layer (27), the unidirectional film (25) on the tertiary filter press plate (23) is jacked up and flows into the buffer groove (8).