Dry powder continuous mixing method and system

Abstract

The invention relates to the technical field of oil field fracturing operation, in particular to a dry powder continuous mixing method and system. The dry powder continuous mixing method comprises the following steps: pumping a solvent into a first liquid inlet of a first mixer, and forming first pressure at a first powder inlet of the first mixer; under the action of the first pressure, dry powder enters a first mixer from a first powder inlet through a first dry powder conveying pipeline from a first storage tank, and is mixed with a solvent at a first mixing position in the first mixer to form a first mixed solution; the first mixed solution is discharged from a first liquid outlet of the first mixer, enters a first separator through a first liquid inlet, and is mixed and further degassed to form a second mixed solution. By adopting the technical scheme, the negative pressure is formed in the first mixer to drive the dry powder in the storage tank to be mixed with the solvent in the first mixer, so that continuous preparation of the oilfield fracturing fluid is realized, and the preparation efficiency and the preparation quality can be remarkably improved.

Description

Technical Field

[0001] This application relates to the technical field of oilfield fracturing operations. Specifically, it relates to a dry powder continuous mixing method and system. Background Art

[0002] Oilfield fracturing fluid is a key working fluid for enhancing oil and gas production in oil and gas wells and water injection in water wells. It forms fractures by high-pressure injection into the formation and carries proppants to fill them, so as to improve the oil and gas flow channels. It usually includes types such as water-based fracturing fluid and oil-based fracturing fluid.

[0003] Water-based fracturing fluid is usually prepared manually by mixing dry powder such as polyacrylamide with water to obtain a solution with a specific concentration or viscosity. However, in the prior art, the preparation method of fracturing fluid has low efficiency and is prone to uneven mixing, resulting in situations such as "fish eyes" or caking, which affect the stability of the fracturing fluid.

[0004] Therefore, there is an urgent need in this field for a dry powder continuous mixing method and system to solve the above technical problems.

[0005] In view of this, this application is proposed. Summary of the Invention

[0006] The purpose of this application is to provide a dry powder continuous mixing method and system to solve at least one of the technical problems mentioned in the background art.

[0007] Specifically, in the first aspect of this application, a dry powder continuous mixing method is provided, including the steps of:

[0008] Pump the solvent into the first liquid inlet of the first mixer through a liquid inlet pump, and form a negative pressure at the first powder inlet of the first mixer, and this negative pressure is the first pressure;

[0009] Under the action of the first pressure, the dry powder enters the first mixer from the first powder inlet through the first dry powder conveying pipeline from the first storage tank, and is mixed with the solvent at the first mixing position in the first mixer to form a first mixed solution;

[0010] The first mixed solution is discharged from the first liquid outlet of the first mixer, enters the first separator through the first liquid inlet, and undergoes degassing and further mixing to form a second mixed solution. A spiral sheet is arranged in the first separator.

[0011] By adopting the above technical solution, by forming a negative pressure in the first mixer, the dry powder in the storage tank is driven to be mixed with the solvent in the first mixer, realizing continuous liquid preparation for oilfield fracturing fluid, and significantly improving the liquid preparation efficiency and liquid preparation quality.

[0012] Preferably, the first dry powder conveying pipeline is provided with a first air inlet for providing an atmospheric source for the first dry powder conveying pipeline.

[0013] Preferably, the first dry powder conveying pipeline forms a buffer bin, and the buffer bin has an internal cavity with a certain volume to ensure uniform and continuous conveying of the dry powder. The first air inlet is symmetrically distributed with the powder discharge port on the buffer bin.

[0014] Preferably, dry air is introduced into the first storage tank to fluidize the dry powder.

[0015] Preferably, the solvent enters the shunt through the liquid inlet pump to form a first path of solvent and a second path of solvent. The first path of solvent can enter the first liquid inlet of the first mixer through the first lifting pipeline, and the second path of solvent can enter the second liquid inlet of the second mixer through the second lifting pipeline.

[0016] Preferably, a first valve is provided on the first lifting pipeline, and a second valve is provided on the second lifting pipeline. The first valve and the second valve are independently controlled and are used to open or close the shunt or adjust the shunt flow rate.

[0017] Preferably, a negative pressure of the second pressure is formed at the second powder inlet of the second mixer.

[0018] Preferably, the inner diameter of the first powder inlet is smaller than that of the second powder inlet, and the inner diameter of the first liquid inlet is smaller than that of the second liquid inlet.

[0019] Preferably, the first pressure is -0.1 Mpa to 0 Mpa, and / or the second pressure is -0.1 Mpa to 0 Mpa.

[0020] More preferably, the first pressure is -0.1 Mpa to -0.05 Mpa, and / or the second pressure is -0.1 Mpa to -0.05 Mpa.

[0021] In the second aspect of the present application, a dry powder continuous mixing system is provided, including.

[0022] A dry powder storage device, including a storage tank for storing dry powder,

[0023] A fracturing fluid mixing device, including an equipment room. The equipment room includes a lifting and shunting system. The lifting and shunting system includes a first liquid inlet pipeline, a liquid inlet pump, and a first liquid supply pipeline that are connected in sequence. The liquid inlet pump pumps the liquid in the first liquid inlet pipeline to the dry powder mixing system at a higher position through the first liquid supply pipeline. The dry powder mixing system includes a first powder inlet, a first liquid inlet, and a first discharge port. The first liquid inlet is connected to the first liquid supply pipeline; the first powder inlet is connected to the storage tank through a dry powder conveying pipeline;

[0024] Among them, the dry powder mixing system includes a first mixer and a first separator that are detachably arranged in sequence. A negative pressure is formed inside the first mixer for mixing dry powder and liquid to form a first mixed solution. The first separator is used for degassing and further mixing the first mixed solution to form a second mixed solution, and discharging it from the first discharge port to the equipment room.

[0025] In summary, the present application has the following beneficial effects:

[0026] First, in the dry powder continuous mixing method provided by the present application, by forming a negative pressure inside the first mixer, the dry powder in the storage tank is driven to be mixed with the solvent in the first mixer, realizing continuous liquid preparation for oilfield fracturing fluid, and significantly improving the liquid preparation efficiency and quality.

[0027] Second, in the dry powder continuous mixing method provided by the present application, by setting a diverter, the solvent can be divided into two paths for transportation and solutions can be respectively prepared in different mixers, realizing the improvement of the mixing efficiency and also enhancing the adaptability of this method to oil wells.

[0028] Third, in the dry powder continuous mixing system provided by the present application, by dividing the mixing system into relatively independent storage devices and mixing devices, it is more convenient for equipment assembly and deployment. Further, by detachably arranging the mixer and separator in the dry powder mixing system, while ensuring the mixing effect of the fracturing fluid, it is more convenient for equipment maintenance and transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0030] Figure 1 It is a schematic diagram of the dry powder continuous mixing method in some embodiments of the present application;

[0031] Figure 2 It is a schematic diagram of the dry powder continuous mixing system from the first angle in some embodiments of the present application;

[0032] Figure 3 It is a schematic diagram of the dry powder continuous mixing system from the second angle in some embodiments of the present application;

[0033] Figure 4 It is a side view of the dry powder continuous mixing system in some embodiments of the present application;

[0034] Figure 5Schematic diagram of the dry powder storage device in some embodiments of the present application;

[0035] Figure 6 Schematic diagram of the lifting and diverting system and dry powder mixing system inside the equipment room at the first angle in some embodiments of the present application;

[0036] Figure 7 Schematic diagram of the lifting and diverting system and dry powder mixing system inside the equipment room at the second angle in some embodiments of the present application;

[0037] Figure 8 First side view of the fracturing fluid mixing device in some embodiments of the present application;

[0038] Figure 9 is Figure 7 Cross-sectional view at the A-A angle of;

[0039] Figure 10 Second side view of the fracturing fluid mixing device in some embodiments of the present application;

[0040] Figure 11 is Figure 9 Cross-sectional view at the C-C angle of;

[0041] Figure 12 Schematic diagram of the inside of the operation room in some embodiments of the present application;

[0042] Figure 13 Front view of the fracturing fluid mixing device in some embodiments of the present application;

[0043] Figure 14 Schematic diagram of the support method of the separator in some embodiments of the present application;

[0044] Figure 15 Cross-sectional view of the mixer in some embodiments of the present application.

[0045] Description of reference numerals

[0046] Through the above description of reference numerals, combined with the embodiments of the present application, the technical solution of the present application can be more clearly understood and described.

[0047] 100, dry powder storage device; 110, storage tank; 120, screw conveyor; 130, buffer bin; 131, first powder outlet; 132, first air inlet;

[0048] 200, fracturing fluid mixing device;

[0049] 210, equipment room;

[0050] 211. Lift shunt system; 2111. First liquid inlet pipeline; 2112. Liquid inlet pump; 2113. First liquid supply pipeline; 21131. First bending structure; 21132. Second bending structure; 21133. Straight pipe body; 2114. Upper water inlet; 2115. Shunt device; 2116. First lifting pipeline; 2117. Second lifting pipeline;

[0051] 212. Dry powder mixing system; 2121. First mixer; 21211. First powder inlet; 21212. First liquid inlet; 21213. First liquid outlet; 2122. First separator; 21221. First discharge port; 21222. First liquid inlet; 21223. First exhaust pipe; 21224. First hanging ear; 2123. Second mixer; 21231. Second powder inlet; 21232. Second liquid inlet; 21233. Second liquid outlet; 2124. Second separator; 21241. Second discharge port; 21242. Second liquid inlet; 21243. Second exhaust pipe; 21244. Second hanging ear;

[0052] 213. Lifting mechanism; 2131. Mounting frame; 21311. First cross bar; 21312. First vertical bar; 21313. Second vertical bar; 21314. First diagonal bar; 21315. Second diagonal bar; 21316. Second cross bar; 2132. First lifting rod; 21321. Fixed rod; 21322. Telescopic rod; 21323. Rocker; 2134. Second lifting rod; 2136. First cavity; 2137. Bearing shaft; 2138. First support position;

[0053] 214. Liquid addition pump;

[0054] 215. Third wall panel; 2151. First support plate; 216. Fourth wall panel; 2161. Second door body:

[0055] 220. Operation room; 221. First wall panel; 2211. First door body; 222. Second wall panel; 225. Distribution box; 226. Operation cabinet; 227. Temperature regulating device; 228. Flowmeter; 230. First partition board;

[0056] 300. Fixed frame; 310. First mounting plate;

[0057] 410. First pipe body; 411. Bending part; 4111. First opening; 4112. Second opening; 4113. First mixing position; 412. Extension part; 420. Second pipe body; 421. First pipe end; 422. Second pipe end; 430. Third pipe body;

[0058] 501. First cover body; 502. Second cover body; 503. Third cover body;

[0059] 610, the first support bracket;

[0060] 710, air compressor; 720, dryer; 730, compressed air tank;

[0061] 810, the first baffle;

[0062] 900, dry powder delivery pipeline; 910, mixed liquid delivery pipeline. Detailed implementation manners

[0063] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0064] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "the", and "said" used in the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0065] The present application will be described in detail below through embodiments.

[0066] Oilfield fracturing fluid is a key working fluid for increasing production of oil and gas wells and injection of water wells. It forms fractures by high-pressure injection into the formation and carries proppants to fill them to improve the oil and gas flow channels, and usually includes types such as water-based fracturing fluid and oil-based fracturing fluid. Water-based fracturing fluid is usually artificially prepared by mixing dry powder such as polyacrylamide with water to obtain a solution with a specific concentration or viscosity. However, in the prior art, the preparation method of fracturing fluid has low efficiency and is prone to uneven mixing, resulting in situations such as "fish eyes" or agglomeration, which affects the stability of the fracturing fluid.

[0067] To solve the technical problems existing in the existing dredging equipment in the background art, the inventive concept of this application is to provide a dry powder continuous mixing method to solve at least one of the technical problems mentioned in the background art. The dry powder continuous mixing method includes the steps of: pumping a solvent into the first liquid inlet of the first mixer through a liquid inlet pump, and creating a negative pressure at the first powder inlet of the first mixer, and this negative pressure is the first pressure; under the action of the first pressure, the dry powder enters the first mixer from the first storage tank through the first dry powder conveying pipeline from the first powder inlet, and is mixed with the solvent at the first mixing position in the first mixer to form a first mixed solution; the first mixed solution is discharged from the first liquid outlet of the first mixer and enters the first separator through the first liquid inlet for degassing and further mixing to form a second mixed solution, and spiral fins are arranged in the first separator.

[0068] According to this inventive concept, by creating a negative pressure in the first mixer, the dry powder in the storage tank is driven to be mixed with the solvent in the first mixer, realizing the continuous liquid preparation of the oilfield fracturing fluid, and significantly improving the liquid preparation efficiency and liquid preparation quality.

[0069] To better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the specification drawings and specific embodiments.

[0070] Based on the inventive concept of this application, in some preferred embodiments of this application, a dry powder continuous mixing method is provided for preparing oilfield fracturing fluid. The oilfield fracturing fluid is usually formed by mixing dry powder with a solvent (such as pure water) to form a solution with a certain viscosity; in some embodiments, the dry powder can be polyacrylamide.

[0071] In some preferred embodiments, the oilfield fracturing fluid further includes an additive, and the additive is selected from at least one of a crosslinking agent, a pH regulator, and a surfactant.

[0072] Specifically, as Figure 1 shown, the dry powder continuous mixing method includes the steps of:

[0073] S100, the step of controlling the mixer to generate a negative pressure:

[0074] Pump the solvent into the first liquid inlet of the first mixer through a liquid inlet pump, and create a negative pressure at the first powder inlet of the first mixer, and this negative pressure is the first pressure.

[0075] In a specific embodiment, the solvent can be pure water, and the flow rate of the solvent is controlled by a liquid inlet pump, so that after the solvent enters the first mixer, a negative pressure is generated in the cavity of the first mixer. In some preferred embodiments, the first pressure is p1, which is -0.1MPa to 0Mpa, preferably -0.1MPa to -0.05Mpa.

[0076] Furthermore, let the flow rate of the solvent in the pipeline be v1, the inner diameter of the pipeline be d1, and the cavity volume of the first mixer be V1. The above parameters satisfy the following formula:

[0077] V1 = v1 * π * (d1 / 2) 2 . By adopting the above technical solution, the applicant obtained the preferred relationship of the above parameters through experiments on the flow rate, pipeline inner diameter, and cavity volume, which can form a suitable first negative pressure in the cavity of the first mixer, so that the dry powder and the solvent meet at a suitable ratio or speed, and the obtained fracturing fluid has better mixing effect and stability.

[0078] S300, first mixing step:

[0079] Under the action of the first pressure, the dry powder enters the first mixer from the first powder storage tank through the first dry powder conveying pipeline from the first powder inlet, and is mixed with the solvent at the first mixing position in the first mixer to form a first mixed solution.

[0080] The first mixer has a first powder inlet, which is connected to the storage tank through the first dry powder conveying pipeline. Since the solvent enters the cavity at a high speed, a negative pressure is generated that can make the dry powder pass through the first dry powder conveying pipeline.

[0081] In some preferred embodiments, the first dry powder conveying pipeline has a first air inlet for increasing the external air pressure of the dry powder conveying pipeline to facilitate the conveying of the dry powder.

[0082] Furthermore, the first dry powder conveying pipeline forms a buffer bin, and the buffer bin has an internal cavity with a certain volume to ensure the uniform and continuous conveying of the dry powder. Those skilled in the art can understand that the uniform and continuous conveying does not mean the absolute uniformity of the feeding speed, but can control the variation of the feeding speed within a reasonable range.

[0083] S400, secondary mixing step:

[0084] The first mixed solution is discharged from the first liquid outlet of the first mixer, enters the first separator through the first liquid inlet, and undergoes degassing and further mixing to form a second mixed solution. A spiral sheet is arranged in the first separator.

[0085] In a specific embodiment, the first mixed solution realizes degassing and further mixing in the first separator, and is discharged into the sand mixing truck after generating the second mixed solution for use in oilfield fracturing.

[0086] By adopting the above technical solution, a negative pressure is formed in the first mixer to drive the dry powder in the storage tank and the solvent to be mixed in the first mixer, so as to realize the continuous preparation of the oilfield fracturing fluid, which can significantly improve the preparation efficiency and quality.

[0087] In some preferred embodiments, the method further includes the steps of:

[0088] S200, introducing dry air into the first storage tank to fluidize the dry powder.

[0089] In the specific implementation process, the fluidization of the dry powder is realized by a fluidized bed arranged at the bottom of the first storage tank to prevent the dry powder from clogging in the storage tank during transportation.

[0090] It can be understood that steps S100 and S200 do not limit the sequence relationship of the above two steps, and those skilled in the art can adjust the sequence of the above two steps according to actual needs.

[0091] In some preferred embodiments, the method further includes the steps of:

[0092] The solvent enters the flow divider through the feed pump to form a first path of solvent and a second path of solvent. The first path of solvent can enter the first liquid inlet of the first mixer through the first lifting pipeline, and the second path of solvent can enter the second liquid inlet of the second mixer through the second lifting pipeline.

[0093] In the specific implementation process, the present application further includes a second mixer for mixing more dry powder. The second mixer is similar in structure to the first mixer, but the difference lies in the volume of the internal cavity and the sizes of the powder inlet, liquid inlet, and liquid outlet, so as to adapt to the preparation of fracturing fluids with different mixing and preparation efficiencies.

[0094] In some preferred embodiments, the first mixer and the second mixer are located at a certain height to facilitate controlling the pressure when the solvent enters the liquid inlet and also facilitate the transfer of the mixed solution.

[0095] In some preferred embodiments, a first valve is provided on the first lifting pipeline, and a second valve is provided on the second lifting pipeline. The first valve and the second valve are independently controlled and are used to open or close the branch or adjust the branch flow rate.

[0096] In the specific implementation process, the inner diameters of the first lifting pipeline and the second lifting pipeline are different and can be respectively controlled by the first valve and the second valve to realize the independent control of the two mixers for adapting to different on-site preparation requirements.

[0097] Understandably, in some other embodiments, the diverter may divide the solvent into more flow paths, such as the third solvent path, the fourth solvent path, etc., and the present application does not make further limitations thereto.

[0098] In some embodiments, the feeding speed of the dry powder is 0.5 - 100 kg / min, and the liquid feeding speed of the solvent is 0.5 - 2.5 m 3 / min; the feeding speed is the speed at which the dry powder enters the first mixer or the powder inlet of the second mixer, and the liquid feeding speed is the speed at which the solution enters the first mixer or the liquid inlet of the second mixer.

[0099] In some other embodiments of the present application, the present application further provides a dry powder continuous mixing system. Specifically, as Figures 2 - 4 shown, the dry powder continuous mixing system includes:

[0100] A dry powder storage device 100, including a storage tank 110 for storing dry powder; a fracturing fluid mixing device 200 for mixing dry powder with water to form an oilfield fracturing fluid with physical properties meeting the requirements.

[0101] In the specific implementation process, the fracturing fluid mixing device 200 and the dry powder storage device 100 are independently arranged, that is, the positions of both can be adjusted by the user according to actual needs.

[0102] In some preferred embodiments, referring to Figures 6 - 7 , the fracturing fluid mixing device 200 includes an equipment room 210, the equipment room 210 includes a lifting and diverting system 211, the lifting and diverting system 211 includes a first liquid inlet pipeline 2111, a liquid inlet pump 2112, and a first liquid feeding pipeline 2113 that are connected in sequence. The liquid inlet pump 2112 pumps the liquid in the first liquid inlet pipeline 2111 through the first liquid feeding pipeline 2113 to a dry powder mixing system 212 located at a higher position. The dry powder mixing system 212 includes a first powder inlet 21211, a first liquid inlet 21212, and a first discharge port 21221. The first liquid inlet 21212 is connected to the first liquid feeding pipeline 2113; the first powder inlet 21211 is connected to the storage tank 110 through a dry powder conveying pipeline 900.

[0103] In the specific implementation process, the dry powder mixing system 212 is farther from the bottom of the equipment room 210 relative to the liquid inlet pump 2112, that is, it is in a higher position. Such a setting is beneficial to making full use of the space of the equipment room 210, reducing the floor area, and at the same time facilitating the pipeline layout between the equipment room or it and the dry powder storage device.

[0104] In some preferred embodiments, continue to refer to Figures 6 - 7, the dry powder mixing system 212 includes a first mixing mechanism, which successively includes a detachably arranged first mixer 2121 and a first separator 2122. A negative pressure is formed inside the first mixer 2121 for mixing dry powder and liquid to form a first mixed solution; the first separator 2122 is used for degassing and further mixing the first mixed solution to form a second mixed solution, and discharging it from the first discharge port 21221 to the equipment room 210. In some embodiments, the second mixed solution will be transported to the sand mixing truck through the mixed liquid transportation pipeline 910 for the final preparation and use of the fracturing fluid.

[0105] With the above technical solutions, by dividing the mixing system into relatively independent storage devices and mixing devices, it is more convenient for the assembly and deployment of the equipment; further, by detachably arranging the mixer and separator in the dry powder mixing system, while ensuring the mixing effect of the fracturing fluid, it is more convenient for the maintenance and transportation of the equipment.

[0106] In the embodiments of the following aspects, the applicant will describe in detail the dry powder storage device 100 described in this application.

[0107] In some preferred embodiments, referring to Figure 5 , the dry powder storage device 100 further includes a screw conveyor 120 and a buffer bin 130. The screw conveyor 120 transports the dry powder in the storage tank 110 to the buffer bin 130 and enters the dry powder transportation pipeline 900 from the first powder outlet 131 of the buffer bin 130.

[0108] In the specific implementation process, the buffer bin 130 has an internal cavity with a certain volume to prevent the dry powder from being quickly extracted and causing discontinuous dry powder transportation; further, the buffer bin 130 also has a first air inlet 132, which can be arranged on the opposite side of the first powder outlet 131 to provide external atmospheric pressure for the dry powder transportation pipeline 900 and prevent the formation of negative pressure in the dry powder transportation pipeline 900, affecting the transportation of dry powder.

[0109] In some preferred embodiments, continuing to refer to Figure 5 , the storage tank 110 is approximately funnel-shaped, and a fluidized bed is arranged at its bottom for transporting the dry powder to the screw conveyor 120 and improving the transportation efficiency of the dry powder; in this embodiment, the screw conveyor 120 is arranged horizontally and includes a powder inlet communicating with the fluidized bed and a powder outlet communicating with the buffer bin 130 to reduce the influence of gravity during this section of dry powder transportation and improve the stability of dry powder transportation.

[0110] In some preferred embodiments, referring to Figures 2 - 3, the dry powder continuous mixing system further includes a fixed frame 300. A first fixed plate 310 is provided at the top of the fixed frame 300, and the dry powder storage device 100 is connected to the first fixed plate 310 only through the top of the storage tank 110. Since the air pressure is relatively high during dry powder transportation, the pipeline may inevitably vibrate. The above setting can ensure that the dry powder storage device 100 has a certain deformable space at the lower part while being stably fixed, reduce the metal fatigue of the bottom structure of the dry powder storage device 100 during dry powder transportation, and improve the service life of the equipment.

[0111] In the embodiments of the following aspects, the applicant will describe the fracturing fluid mixing device 200 described in the present application in detail.

[0112] In some preferred embodiments, the fracturing fluid mixing device 200 further includes an operation room 220 adjacent to the equipment room 210. Refer to Figures 8 - 13 , the operation room 220 includes a first wall plate 221 and a second wall plate 222 arranged oppositely. The first wall plate 221 is provided with a lockable first door body 2211 for isolating the internal and external environments of the operation room 220. The equipment room 210 includes a third wall plate 215 and a fourth wall plate 216 arranged oppositely. The fourth wall plate 216 is provided with a lockable second door body 2161 for isolating the internal and external environments of the equipment room 210. The first wall plate 221 and the fourth wall plate 216 are located on two opposite sides to prevent the staff in the equipment room and the operation room from interfering with each other when entering and leaving.

[0113] In some preferred embodiments, refer to Figure 13 , the third wall plate 215 is provided with a first support plate 2151. The first support plate 2151 is hinged to the third wall plate 215 and has a first position and a second position. When the first support plate 2151 is in the first position, it is in the vertical direction. When the first support plate 2151 is in the second position, it forms a substantially perpendicular angular relationship with the third wall plate 215 for placing items, so as to place working or maintenance equipment during equipment maintenance or debugging at the oil well work site.

[0114] In some preferred embodiments, refer to Figures 8 - 13, a distribution box 225, an operation cabinet 226, a temperature adjustment device 227, and a flowmeter 228 are provided in the operation room 220; a first partition board 230 is provided between the operation room 220 and the equipment room 210, and an observation window is provided on the first partition board 230; the operation cabinet 226 is arranged close to the first partition board 230 and includes a display operation panel arranged from top to bottom, an operation platform close to the horizontal, and a cabinet body; the flowmeter 228 is arranged on the first partition board 230 and is slightly higher than the top end of the operation cabinet 226. With the above technical solution, it is possible for the staff to more conveniently observe the internal situation of the equipment room when controlling the operation cabinet, which is beneficial to early warning and improves the safety of the equipment.

[0115] Further, the temperature adjustment device 227 can be an air conditioner, which is arranged on the second wall panel 222 and is arranged opposite to the first door body 2211, so that the temperature adjustment in the operation room is more gentle and avoids adverse effects on the health of the staff.

[0116] In some preferred embodiments, the first liquid inlet pipeline 2111 is connected to at least one water inlet 2114, and a butterfly valve is arranged at the water inlet 2114 for opening and closing the water inlet 2114; the first liquid inlet pipeline 2111 is connected to the first side surface of the liquid inlet pump 2112, and the second side surface of the liquid inlet pump 2112 is connected to the first liquid supply pipeline 2113, and the first side surface and the second side surface are adjacent. The first liquid supply pipeline 2113 includes first bending structures 21131 and 21132 located at both ends and having the same bending direction, and a straight pipe body 21133 located between them. With the above technical solution, the pipeline layout inside the equipment room can be made more compact, improving the utilization rate of the space inside the equipment room.

[0117] In some embodiments, there are 4 water inlets 2114, and the 4 water inlets 2114 are arranged side by side and at intervals, and are simultaneously connected to the first liquid inlet pipeline 2111 to ensure that the liquid inlet speed meets the requirements of liquid preparation.

[0118] In some preferred embodiments, as Figures 6 - 7 shown, the first mixer 2121 includes a first powder inlet 21211, a first liquid inlet 21212, and a first liquid outlet 21213, the first separator 2122 includes a first liquid inlet 21222 and a first discharge port 21221, and the first liquid outlet 21213 is connected to the first liquid inlet 21222.

[0119] Specifically, in some embodiments, referring to Figure 15, the first mixer 2121 is composed of a first pipe body 410, a second pipe body 420, and a third pipe body 430. The first pipe body 410 includes a bent portion 411 and an extension portion 412. The bent portion 411 includes a first opening 4111 and a second opening 4112 at both ends. The extension portion 412 is connected to the bent portion 411 and extends in a direction away from the second opening 4112. A first liquid inlet 21212 is formed at the first opening 4111. The second pipe body 420 has a first pipe end 421 and a second pipe end 422 in its length direction. The first pipe end 421 extends into the cavity of the bent portion 411 through the extension portion 412 to form a first mixing position 4113. The liquid transported by the first upper liquid pipeline 2113 and the dry powder transported by the dry powder transportation pipeline 900 are fully mixed at this position. A first powder inlet 21211 is formed at the second pipe end 422. The third pipe body 430 is connected to the second opening 4112 and forms a first liquid outlet 21213 at one end.

[0120] In some embodiments, the first liquid outlet 21213 is connected to the first liquid inlet 21222 of the first separator 2122. Preferably, the two are connected by a union. A spiral guide vane is provided inside the first separator 2122 to achieve degassing and further mixing of the first mixed solution. In some preferred embodiments, the first liquid inlet 21222 and the first discharge port 21221 are eccentrically arranged to improve the degassing effect of the first mixed solution.

[0121] Furthermore, a first exhaust pipe 21223 is provided at a position near the first liquid inlet 21222 in the upper part of the first separator 2122. The first exhaust pipe 21223 is of a bent structure and extends in a direction away from the first liquid inlet 21222 to ensure the exhaust effect.

[0122] In some preferred embodiments, continue to refer to Figures 6 - 7 , the dry powder mixing system 212 includes a second mixing mechanism arranged at an interval from the first mixing mechanism. The second mixing mechanism sequentially includes a second mixer 2123 and a second separator 2124 that are detachably arranged. The working principle of the second mixing mechanism is similar to that of the first mixing mechanism. Among them, the second mixer 2123 includes a second powder inlet 21231, a second liquid inlet 21232, and a second liquid outlet 21233. The second separator 2124 includes a second liquid inlet 21242, a second discharge port 21241, and a second exhaust pipe 21243. The second liquid outlet 21233 is connected to the second liquid inlet 21242.

[0123] In some preferred embodiments, the inner diameter of the first powder inlet 21211 is smaller than that of the second powder inlet 21231, and the inner diameter of the first liquid inlet 21212 is smaller than that of the second liquid inlet 21232; further, the second mixer 2123 has a second mixing position similar to the first mixing position 4113, and the inner diameter of the cavity at the first mixing position is smaller than that of the cavity at the second mixing position.

[0124] By adopting the above technical solution, by setting two sets of mixing mechanisms with different specifications, it is possible to adapt to the configuration of fracturing fluids in different scenarios and different requirements, improve the adaptability of the equipment, and when the two sets of mixing mechanisms are used simultaneously, it is also possible to improve the liquid preparation efficiency and effectively reduce the time cost of liquid preparation.

[0125] In some preferred embodiments, the first liquid supply pipeline 2113 is provided with an electric control valve and an electromagnetic flowmeter at intervals for controlling and monitoring the liquid supply flow rate.

[0126] In some preferred embodiments, continue to refer to Figures 6 - 7 , the end of the second bending structure 21132 is connected to a diverter 2115, the diverter 2115 divides the upper water into at least two paths, and sends the liquid to the first liquid inlet 21212 and the second liquid inlet 21232 respectively through the first lifting pipeline 2116 and the second lifting pipeline 2117, wherein the diameters of the first lifting pipeline 2116 and the second lifting pipeline 2117 are different. In some embodiments, the diameter of the first lifting pipeline 2116 is DN100 (100 mm), and the diameter of the second lifting pipeline 2117 is DN80 (80 mm); further, electric control valves are respectively arranged at positions close to the lower end of the first lifting pipeline 2116 and the second lifting pipeline 2117 for controlling the operation or stop of the mixing mechanism.

[0127] In some preferred embodiments, refer to Figures 8 - 11 , the equipment room 210 further includes a lifting mechanism 213 for adjusting the height of the mixing mechanism, the lifting mechanism 213 includes a driving device and a mounting frame 2131, the driving device includes a first lifting rod 2132 installed on the third wall panel 215, and a first power device for driving the first lifting rod 2132. In some embodiments, the first lifting rod 2132 includes a fixed rod 21321 and a telescopic rod 21322 that can be movably connected to the fixed rod 21321. Driven by the first power device, the telescopic rod 21322 can move relative to the fixed rod 21321 in its length direction and form at least a first position and a second position.

[0128] Furthermore, the first mixer 2121 and the second mixer 2123 are fixedly arranged at one end of the mounting frame 2131 close to the third wall panel 215, and the first separator 2122 and the second separator 2124 are fixedly arranged at one end of the mounting frame 2131 close to the fourth wall panel 216. Since the first mixer and the second mixer are to be connected to the dry powder conveying pipeline, and the dry powder conveying pipeline is arranged from bottom to top, adopting the solution in this embodiment to arrange the mixer on the side close to the third wall panel and away from the second door body can reduce the interference of the dry powder conveying pipeline to the staff when entering the equipment room, and improve the safety of the equipment operation.

[0129] Understandably, the first power device can control the telescopic rod in a conventional manner in the art. In some embodiments, the fixed rod 21321 is sleeved outside the telescopic rod 21322. The first power device includes a rocker 21323 located at the bottom end of the first lifting rod 2132. The telescopic rod 21322 is controlled by rotating the rocker 21323, and the control method can be screw drive or hydraulic drive, etc. Adopting the above solution to arrange the rocker at the bottom of the first lifting rod is convenient for the operation of the staff.

[0130] In some preferred embodiments, continue to refer to Figures 8 - 11 , the top end of the telescopic rod 21322 is fixedly connected to the mounting frame 2131, and the mounting frame 2131 is lifted by the movement of the telescopic rod 21322. In some embodiments, the mounting frame 2131 includes a first cross bar 21311, and both ends of the first cross bar 21311 are respectively connected to a first vertical bar 21312 and a second vertical bar 21313. The telescopic rod 21322 is fixedly connected to the first mounting position of the first cross bar 21311, and the mounting frame 2131 further includes a first diagonal bar 21314 and a second diagonal bar 21315. One end of the first diagonal bar 21314 is fixed to one side of the first mounting position, and the other end is fixed to the first vertical bar 21312. One end of the second diagonal bar 21315 is fixed to the other side of the first mounting position, and the other end is fixed to the second vertical bar 21313. Connecting the telescopic rod and the mounting frame in the above manner can ensure the mechanical strength of the mounting frame during the lifting process and improve the safety of the equipment.

[0131] In some preferred embodiments, the driving device includes a second lifting rod 2134 installed on the fourth wall panel 216, and a second power device for driving the second lifting rod 2132. Similarly, the second lifting rod 2134 is similar to the first lifting rod 2132 and includes a fixed rod and a telescopic rod that can be movably connected to the fixed rod. Driven by the second power device, the telescopic rod can move relative to the fixed rod in its length direction and form at least two positions. The top end of the telescopic rod is fixedly connected to the mounting frame. By moving the telescopic rod, the lifting of the mounting frame is realized. The first lifting rod 2132 and the second lifting rod 2132 are fixed to the mounting frame at corresponding positions. In some embodiments, the mounting frame 2131 includes a second cross bar 21316 symmetrically arranged with the first cross bar 21311. The two ends of the second cross bar 21316 are respectively connected to two parallel vertical rods. The second lifting rod 2132 is fixedly connected to the second mounting position of the second cross bar 21316. The mounting frame 2131 further includes a third diagonal rod and a fourth diagonal rod. One ends of the third diagonal rod and the fourth diagonal rod are respectively connected to two parallel vertical rods, and the other ends are respectively fixed on both sides of the second mounting position to reinforce the second cross bar. Synchronously driving the first lifting rod 2132 and the second lifting rod 2134 can enable the mounting frame to realize the lifting function more smoothly.

[0132] In some preferred embodiments, referring to Figure 3 , the top end of the mounting frame 2131 has an adjustable baffle. The adjustable baffle includes a first cover body 501, a second cover body 502, and a third cover body 503 arranged in sequence. The first cover body 501 and the third cover body 503 are respectively hinged to the second cover body 502, so that both the first cover body 501 and the third cover body 503 can rotate away from the equipment room relative to the second cover body 502. In some embodiments, the first cover body 501 and the third cover body 503 can rotate 180°, so that in specific cases, the first cover body 501 or the third cover body 503 can be placed on the second cover body 502. The first cover body 501 corresponds to the positions of the first mixer 2121 and the second mixer 2123, and the third cover body 503 corresponds to the positions of the first separator 2122 and the second separator 2124. By adopting the above technical solutions, on the one hand, it can cover the first mixing mechanism and the second mixing mechanism to prevent external rain or dust from entering the equipment room during work and ensure the safety of the equipment during work; on the other hand, when the first cover body 501 and the third cover body 503 are opened, it is convenient to repair or replace the mixing mechanism, improving work efficiency.

[0133] In some preferred embodiments, the top ends of the mounting brackets 2131 enclose to form a first cavity 2136. The first mixer 2121 and the second mixer 2123 are disposed through the first cavity 2136, and parts of the second pipe body 420 and the third pipe body 430 are located outside the first cavity 2136, so as to facilitate their connection with the dry powder delivery pipeline and the separator. By adopting the above technical solution, the operating environment of the mixer, which is a key structure of the equipment, can be further ensured to be stable, thereby improving the mixing effect of the fracturing fluid.

[0134] In some preferred embodiments, referring to Figure 14 , one side of the mounting bracket 2131 close to the second lifting rod 2132 has a horizontally arranged bearing shaft 2137. The first separator 2122 and the second separator 2124 are respectively provided with a first hanging ear 21224 and a second hanging ear 21244 on the outer wall. The first hanging ear 21224 and the second hanging ear 21244 are sleeved on the bearing shaft 2137 and can rotate around the bearing shaft 2137.

[0135] When the mixing mechanism is working, one end of the first separator 2122 is connected to the first mixer 2121. The first hanging ear 21224 abuts against the second cross bar 21316 at the first support position 2138 and receives the supporting force of the second cross bar 21316, so that the first separator 2122 can maintain a stable position under the action of the above two points; similarly, one end of the second separator 2124 is connected to the second mixer 2123. The second hanging ear 21244 abuts against the second cross bar 21316 and receives the supporting force of the second cross bar 21316, so that the second separator 2124 can maintain a stable position under the action of the above two points.

[0136] When the mixing mechanism is not working, the first separator 2122 is disconnected from the first mixer 2121. The first separator 2122 can rotate around the bearing shaft 2137 through the first hanging ear 21224 and become a vertical state, which is convenient for its storage; similarly, the second separator 2124 is disconnected from the second mixer 2123. The second separator 2124 can rotate around the bearing shaft 2137 through the second hanging ear 21244 and become a vertical state. Since a better separation state needs to be achieved, the volume of the separator is usually large and it is difficult to directly store it in the equipment room. By adopting the above technical solution, when the mixing mechanism is not working, the connector between the separator and the mixer, such as a union, can be disassembled and the separator can be rotated so that it can be conveniently stored in the equipment room through the lifting mechanism, which is convenient for the transportation or storage of the equipment.

[0137] In some preferred embodiments, referring to Figure 10, at least one liquid addition pump 214 is further provided in the equipment chamber 210 for adding materials to the outside of the equipment chamber 210, such as the second mixed solution in the sand mixer. The liquid addition pump 214 is located near the fourth wall plate 216. A first baffle 810 is provided at a lower position of the fourth wall plate 216 away from the first wall plate 221. The first baffle 810 is hinged to the fourth wall plate 216 and includes an open state and a closed state. When it is in the open state, the liquid addition pump 214 inside the equipment chamber 210 can be connected to an external pipeline. In some embodiments, at least 4 liquid addition pumps 214 are arranged at intervals in the equipment chamber 210, namely a first liquid addition pump, a second liquid addition pump, a third liquid addition pump, and a fourth liquid addition pump, and inlet pipelines are respectively provided.

[0138] In some embodiments, the discharge pipelines of the first liquid addition pump and the second liquid addition pump are connected in parallel through an intermediate pipeline, and a gate is provided on the intermediate pipeline; a flow meter such as a mass flow meter is provided on the discharge pipeline of the first liquid addition pump. When the gate at the end of the discharge pipeline of the second liquid addition pump is closed and the gate on the intermediate pipeline is opened, the first liquid addition pump and the second liquid addition pump share the discharge pipeline of the first liquid addition pump so that they share the flow meter; when the gate at the end of the discharge pipeline of the second liquid addition pump is opened and the gate on the intermediate pipeline is closed, the second liquid addition pump is used independently. The discharge pipelines of the third liquid addition pump and the fourth liquid addition pump are independently arranged, and respective independent flow meters are configured on the discharge pipelines. The flow meters can be electromagnetic or turbine flow meters. By adopting the above technical solutions, the feeding rate of the liquid addition pump can be controlled more flexibly, and the preparation effect of the fracturing fluid can be ensured.

[0139] It can be understood that in some embodiments, the liquid addition pump can be a cam rotor pump with a displacement of 1-10m 3 / h; further, the displacements of the first liquid addition pump and the second liquid addition pump are higher than those of the third liquid addition pump and the fourth liquid addition pump.

[0140] In some preferred embodiments, referring to Figure 9 , a first support frame 610 is provided above the liquid addition pump 214. An air compressor 710 and a dryer 720 are carried on the upper part of the first support frame 610. The air compressor 710 is connected to the dryer 720. The compressed gas enters the compressed air tank 730 located above the dryer 720 after being dried by the dryer 720. The compressed air tank 730 is fixed on the top of the equipment chamber 210. After the compressed gas enters the compressed air tank 730, it is discharged through an exhaust pipeline. An electric control valve is provided on the exhaust pipeline, and the exhaust pipeline is connected to the fluidized bed. By adopting the above technical solutions, the air compression system required by the fluidized bed is integrated in the equipment chamber, saving the occupied space of the equipment and improving the overall integration level of the equipment, which is convenient for the configuration and transportation of the equipment.

[0141] In summary, the dry powder continuous mixing method provided by the present application forms a negative pressure in the first mixer, driving the dry powder in the storage tank and the solvent to be mixed in the first mixer, realizing the continuous preparation of the oilfield fracturing fluid, solving the technical problems of low efficiency and easy uneven mixing in the existing technology for preparing the fracturing fluid, significantly improving the preparation efficiency and quality, and having good application prospects.

[0142] It should be noted that for those of ordinary skill in the art, the technical features in the above embodiments can be freely combined, and the formed technical solutions also belong to the embodiments disclosed in the present application.

[0143] Furthermore, without departing from the principle of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A dry powder continuous mixing method, characterized in that: Including the steps: Pump a solvent into the first liquid inlet of the first mixer through a liquid inlet pump, and create a negative pressure at the first powder inlet of the first mixer, and this negative pressure is the first pressure; Under the action of the first pressure, the dry powder enters the first mixer from the first powder inlet through the first dry powder conveying pipeline from the first storage tank, and is mixed with the solvent at the first mixing position in the first mixer to form a first mixed solution; The first mixed solution is discharged from the first liquid outlet of the first mixer, enters the first separator through the first liquid inlet, and undergoes degassing and further mixing to form a second mixed solution. A spiral sheet is arranged in the first separator.

2. The dry powder continuous mixing method according to claim 1, characterized in that: The first dry powder conveying pipeline is provided with a first air inlet for providing an atmospheric source for the first dry powder conveying pipeline.

3. The dry powder continuous mixing method according to claim 2, characterized in that: The first dry powder conveying pipeline forms a buffer bin, and the buffer bin has an internal cavity with a certain volume to ensure uniform and continuous conveying of the dry powder. The first air inlet is located on the buffer bin and is symmetrically distributed with the powder discharge port.

4. The dry powder continuous mixing method according to claim 1, characterized in that: Introduce dry air into the first storage tank to fluidize the dry powder.

5. The dry powder continuous mixing method according to claim 1, characterized in that: The solvent enters a flow divider through the liquid inlet pump, forming a first path of solvent and a second path of solvent. The first path of solvent can enter the first liquid inlet of the first mixer through the first lifting pipeline, and the second path of solvent can enter the second liquid inlet of the second mixer through the second lifting pipeline.

6. The dry powder continuous mixing method according to claim 5, characterized in that: A first valve is arranged on the first lifting pipeline, and a second valve is arranged on the second lifting pipeline. The first valve and the second valve are independently controlled and are used to open or close the flow path or adjust the flow rate of the flow path.

7. The dry powder continuous mixing method according to claim 6, characterized in that: Create a negative pressure of a second pressure at the second powder inlet of the second mixer.

8. The dry powder continuous mixing method according to claim 7, characterized in that: The inner diameter of the first powder inlet is smaller than that of the second powder inlet, and the inner diameter of the first liquid inlet is smaller than that of the second liquid inlet.

9. The dry powder continuous mixing method according to claim 8, characterized in that: The first pressure is -0.1MPa to 0Mpa; And, Let the flow rate of the solvent in the pipeline be v1, the inner diameter of the pipeline be d1, and the cavity volume of the first mixer be V1. The above parameters satisfy the following formula: V1 = v1 * π * (d1 / 2) 2 .

10. A dry powder continuous mixing system, characterized in that: Including: A dry powder storage device, including a storage tank for storing dry powder, A fracturing fluid mixing device includes an equipment room, and the equipment room includes a lifting and shunting system. The lifting and shunting system includes a first liquid inlet pipeline, a liquid inlet pump, and a first liquid feeding pipeline that are connected in sequence. The liquid inlet pump pumps the liquid in the first liquid inlet pipeline through the first liquid feeding pipeline to a dry powder mixing system located at a higher position. The dry powder mixing system includes a first powder inlet, a first liquid inlet, and a first discharge port. The first liquid inlet is connected to the first liquid feeding pipeline; the first powder inlet is connected to a storage tank through a dry powder conveying pipeline; wherein, the dry powder mixing system includes a first mixer and a first separator that are detachably arranged in sequence. A negative pressure is formed inside the first mixer for mixing dry powder and liquid to form a first mixed solution; the first separator is used for degassing and further mixing the first mixed solution to form a second mixed solution, and discharging the second mixed solution from the first discharge port out of the equipment room.

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