A method for cleaning quartz sand for fracturing

Abstract

The invention relates to the technical field of quartz sand cleaning, and discloses a method for cleaning quartz sand for fracturing. The invention solves the problem that when cleaning quartz sand, due to the gravity of the quartz sand itself, the quartz sand is deposited at the bottom of a scrubbing machine, which easily causes a poor cleaning effect of the quartz sand. When the connecting rod 1 descends, it drives the material-dispensing mechanism to move downward as a whole, so that the rotating gear drives the rotating shaft and the S-shaped rotating paddle to rotate 90 degrees, and the quartz sand accumulated at the bottom of the stirring shell is turned over by the arc surface of the lower end of the S-shaped rotating paddle. When the connecting ring 1 moves upward, the S-shaped rotating paddle moves upward at an angle tending to a plane, and the quartz sand turned over to the upper end of the S-shaped rotating paddle is lifted to the upper end. When the connecting ring 1 moves downward for the second time, it drives the one-way gear to rotate 90 degrees for the second time, and turns the quartz sand at the upper end of the rotating paddle to the other side, so that the quartz sand settled at the bottom of the stirring shell is fully turned over and cleaned.

Description

Technical Field

[0001] The invention relates to the field of quartz sand cleaning technology, in particular to a method for cleaning fracturing quartz sand. Background Art

[0002] In the oil field, fracturing refers to a method of using hydraulic force to form cracks in oil and gas layers during oil or gas production, also known as hydraulic fracturing. Hydraulic fracturing technology refers to pumping fracturing fluid into an oil well under high pressure, resulting in high pressure at the bottom of the well. When the pressure is sufficient to fracture the rock formation, cracks will be generated in the formation and expand forward to a certain space. In order to keep the cracks open, proppants need to be filled into the cracks along with the fracturing fluid after the rock formation is fractured. After the proppants are delivered, the viscosity of the fracturing fluid is reduced and it is refluxed, so that cracks with high conductivity are generated.

[0003] At present, the petroleum fracturing proppants used at home and abroad are generally divided into three categories: quartz sand, expanded clay proppants and coated proppants. In recent years, with the continued sluggishness of oil and gas prices, cost reduction and efficiency improvement have become the main theme of shale gas development. In addition to speeding up drilling and completion and increasing efficiency, North America has greatly reduced the use of expanded clay, while increasing the proportion of quartz sand in fracturing construction, and even eliminating expanded clay, which has greatly reduced the cost of fracturing materials and achieved efficient development of shale gas under low oil and gas prices.

[0004] The existing Chinese patent with publication number CN111822428A discloses a cleaning device and a cleaning method for quartz sand processing. By arranging a first material trough, a second material trough and a third material trough in a rotating cylinder, and correspondingly arranging a first screen and a second screen, the quartz sand can be screened while being cleaned or drained, and is located in different material troughs. By arranging tables of different heights on the bottom plate and cooperating with different material troughs, the three material troughs can be unloaded separately, so that the screened quartz sand can be unloaded and collected in turn, which is convenient for subsequent processing.

[0005] When the device cleans the quartz sand, the quartz sand is concentrated and piled up in the cleaning equipment, and the quartz sand is cleaned in batches. The cleaning efficiency is low and the time consumption is long, which greatly affects the cleaning efficiency.

[0006] The existing Chinese patent with publication number CN219401268U discloses a quartz sand scrubbing machine. By starting a driving motor, the operation of the driving motor will drive the first stirring blade to stir the quartz sand through the stirring rod, and then the first gear will drive the rotating rod to rotate through the second gear, so that the second stirring blade will rotate in an offset manner with the first stirring blade to stir the quartz sand, thereby greatly improving the stirring efficiency of the quartz sand, thereby improving the effect of the scrubbing machine to remove dirt on the surface of the quartz sand particles, and thus achieving the purpose of a good scrubbing effect; at the same time, when the above-mentioned stirring blades are staggered to stir the quartz sand, part of the quartz sand will be stirred to move toward the inner wall of the scrubbing bucket. When this part of the quartz sand moves to the inner wall of the scrubbing bucket, it collides with the scrubbing protrusions on the inner wall of the scrubbing bucket, further improving the scrubbing effect of the quartz sand.

[0007] When the device cleans the quartz sand, due to the gravity of the quartz sand itself, the quartz sand may be deposited at the bottom of the scrubber, and efficient cleaning cannot be performed, which may easily cause poor cleaning effect of the quartz sand and affect the cleaning efficiency.

[0008] Therefore, a method for cleaning fracturing quartz sand is needed. Summary of the invention

[0009] In order to solve all or part of the above problems, the purpose of the present invention is to provide a method for cleaning fracturing quartz sand, so as to solve the problem proposed in the above-mentioned comparative document technology that when cleaning quartz sand, due to the gravity of the quartz sand itself, the quartz sand may be deposited at the bottom of the scrubber, and efficient cleaning cannot be performed, which easily leads to poor cleaning effect of the quartz sand.

[0010] To achieve the above object, the present invention provides the following technical solution: a method for cleaning fracturing quartz sand, comprising the following steps:

[0011] S1: Put the fracturing quartz sand to be cleaned into the scrubber for cleaning, add cleaning liquid into the scrubber, start the stirring device to drive the transmission mechanism and the material-dispensing mechanism to move up and down, and clean the fracturing quartz sand in the scrubber for 30-60 minutes. The scrubber cleaning is divided into two stages; the scrubber can effectively remove clay, mud impurities and some fine-grained iron impurities on the surface of the quartz sand. At the same time, during the scrubbing process, the particle size of the quartz sand is adjusted and optimized to a certain extent to make its particle size distribution more uniform, so that the surface of the quartz sand particles is fully cleaned, and its purity and quality are improved. Start cleaning During washing, the stirring device starts to operate, driving the cleaning liquid and quartz sand to mix fully, and the cleaning liquid is poured into the scrubbing machine. In this process, the hydroxide ions in the alkaline cleaning liquid react with the acidic oxide impurities, and the hydrogen ions in the acidic cleaning liquid react with the carbonate impurities. The surfactant reduces the surface tension and enhances the emulsification and dispersion of the dirt. After the cleaning is completed, water is added for secondary cleaning to prevent the residual substances in the cleaning liquid from reacting with the quartz sand impurities, such as the calcium and magnesium salts remaining after the acidic cleaning liquid cleans the carbonate impurities in the quartz sand. Crystallize on the surface of the quartz sand during subsequent drying. After scrubbing, the quality of the quartz sand is significantly improved, so that it can meet higher standards of industrial application requirements;

[0012] S2: Pour the sludge generated during the cleaning process into the belt filter press for 15-30 minutes of squeezing treatment, and recycle the separated water; the belt filter press is used for sludge treatment, which can greatly reduce the water content of the sludge and reduce its volume, making it easier to transport and dispose of the sludge; the separated water can be recycled to improve water utilization;

[0013] S3: The cleaned fracturing quartz sand is transferred to the dewatering screen for dehydration treatment, and the dehydration time is 10-20 minutes; the dewatering screen can quickly and effectively reduce the water content in the quartz sand. For the fracturing quartz sand dehydration operation with higher requirements, a dewatering screen with precise aperture and adjustable screen angle is selected to ensure that most of the water can be separated from the quartz sand, so that the water content of the dehydrated quartz sand meets the requirements of subsequent treatment. The aperture of the screen is between 0.1-1 mm. For fracturing quartz sand with smaller particle size, a screen with an aperture of 0.1-0.3 mm can be selected; and for quartz sand with slightly larger particle size, the aperture of the screen can be appropriately increased to 0.5-1 mm. The screen material is usually stainless steel or polyurethane. The stainless steel screen has higher strength and wear resistance, while the polyurethane screen has better flexibility and anti-clogging performance.

[0014] S4: The dehydrated fracturing quartz sand is transported to the conveyor and dried by the dryer. The drying time is 30-60 minutes and the drying temperature is 150-250℃. The waste gas generated during the drying process enters the desulfurization tower for purification. The dryer can quickly and effectively reduce the water content in the quartz sand to reach the specified dryness to meet the requirements of subsequent production processes or applications. During the drying process, sulfur dioxide in industrial waste gas is effectively absorbed and removed by chemical or physical methods to reduce the pollution of sulfur dioxide to the atmospheric environment. At the same time, other acidic gases, dust and impurities that may exist in the waste gas can be removed at the same time to achieve comprehensive gas purification.

[0015] S5: The dried fracturing quartz sand is screened by a square swing screen and graded according to particle size. The screening time is 20-40 minutes. The screened fracturing quartz sand enters the PLC automatic packaging machine for metering and packaging to complete the cleaning of the fracturing quartz sand. The square swing screen can perform high-precision grading and screening of quartz sand. According to different particle size requirements, the quartz sand can be accurately divided into multiple particle size levels. The multi-level fracturing quartz sand after screening is accurately measured and controlled by the PLC automatic packaging machine. The weight of each bag of quartz sand is ensured to meet the prescribed standards, reduce errors, achieve efficient and fast packaging operations, greatly improve packaging efficiency, and meet the needs of large-scale production.

[0016] Furthermore, the ratio of the cleaning fluid to the fracturing quartz sand is 2:1. The cleaning fluid serves to disperse the quartz sand particles and prevent them from agglomerating. When the ratio of the cleaning fluid to the fracturing quartz sand is 2:1, the buoyancy and fluidity of the cleaning fluid can allow the quartz sand particles to be dispersed more evenly therein, so that each particle can be fully cleaned. If there is too little cleaning fluid, the quartz sand will easily stick to each other, resulting in cleaning dead corners; too much cleaning fluid will cause the quartz sand particles to be too dispersed.

[0017] Furthermore, a surfactant is added to the cleaning liquid, and the surfactant is one of sodium dodecyl sulfate and polyoxyethylene ether. The ratio of the surfactant to the cleaning liquid is 1:100. The surfactant can effectively reduce the surface tension of the cleaning liquid, so that it can better wet the surface of the quartz sand particles, enhance the emulsification and dispersion ability of dirt, and thus improve the cleaning effect.

[0018] Furthermore, the specific steps of S1 are as follows:

[0019] S11: First, pour quartz sand into the scrubber through the feed pipe, and add cleaning liquid into the liquid inlet;

[0020] S12: Then the stirring device is started to stir and clean the quartz sand in the scrubbing machine, and at the same time drives the bevel gear 1 to rotate. During the rotation process, the bevel gear 1 is driven by two sets of transmission mechanisms to drive the material diverting mechanism to move up and down;

[0021] S13: During stirring, the quartz sand is accumulated at the bottom of the scrubber under the action of gravity, and the quartz sand is turned over by the rotation of the S-shaped rotating paddle inside the material-dispensing mechanism.

[0022] Furthermore, the scrubbing machine is composed of a stirring shell, a stirring device, a feed port, supporting legs, a protective shell, a transmission mechanism, and a material shifting mechanism. A liquid inlet is provided at the upper end of the stirring shell, the liquid inlet is communicated with the interior of the stirring shell, the feed port is fixedly connected and communicated with the feed pipe, the protective shell is fixedly connected to the stirring shell, the stirring device includes a driving motor, a stirring paddle is fixedly installed at the driving end of the driving motor, a bevel gear is fixedly installed on the outer side of the stirring paddle, the stirring paddle penetrates the stirring shell and is rotatably connected thereto, the stirring paddle is driven to rotate by the driving motor, the quartz sand inside the stirring shell is stirred and cleaned, and at the same time the quartz sand is turned over by the S-shaped rotating paddle inside the material shifting mechanism.

[0023] Furthermore, the specific steps of S12 are as follows:

[0024] The stirring paddle is driven by a driving motor to rotate, thereby driving bevel gear 1 to rotate, bevel gear 1 in turn drives two sets of bevel gears 2 to rotate, bevel gear 2 in turn drives connecting column 1 to rotate, connecting column 1 in turn drives rotating rod 1 to rotate along connecting column 1 as the axis, thereby driving rotating rod 2 and connecting column 2 to slide in the square frame and driving the connecting frame to reciprocate up and down, thereby making the two sets of connecting column 2 slide up and down in the U-shaped connecting rod, realizing the up and down movement of the material diverting mechanism.

[0025] Furthermore, the transmission mechanism includes bevel gear two, which meshes with bevel gear one, a connecting column one is fixedly installed on one side of the bevel gear two, a fixing plate is rotatably installed on the outer side of the connecting column one, the lower end of the fixing plate is fixedly connected to the stirring shell, a U-shaped connecting rod is rotatably provided on one end of the connecting column one, the lower end of the U-shaped connecting rod is fixedly connected to the stirring shell, a square groove one is penetrated through the middle part of the U-shaped connecting rod, one end of the connecting column one penetrates the U-shaped connecting rod and is fixedly installed with a rotating rod one, a rotating rod two is rotatably installed on the side of the U-shaped connecting rod away from the connecting column one, one side of the rotating rod two is rotatably connected to the rotating rod one, and the rotating A connecting column 2 is fixedly installed on the other side of the second rod, a square frame is slidably provided on the outer side of the second connecting column, a connecting frame is provided on the outer side of the square frame, a square groove 2 is penetrated through the interior of the connecting frame, a rotating rod 1 is fixedly connected to the surface of the second square groove, the second square groove is the same size as the first square groove, two groups of connecting columns 2 are fixedly installed on the lower end of the connecting frame, the two groups of connecting columns 2 pass through the U-shaped connecting rod and are slidably connected to it, the lower ends of the two groups of connecting columns 2 pass through the mixing shell and are fixedly installed with a connecting plate, the connecting column 2 is slidably connected to the mixing shell, the lower end of the connecting plate is fixedly installed with a connecting rod 1, and the lower end of the connecting rod 1 is fixedly connected to the material diverting mechanism.

[0026] Furthermore, the specific steps of S13 are as follows:

[0027] During the descent process, the connecting rod drives the entire material-discharging mechanism to move downward. Because the rotating gear is in meshing state with the tooth row, the rotating gear drives the rotating shaft and the S-shaped rotating paddle to rotate 90°, and the quartz sand accumulated at the bottom of the stirring shell is turned over by the arc surface of the lower end of the S-shaped rotating paddle. When the connecting ring moves upward, under the action of the friction between the one-way gear, the rotating shaft and the connecting ring, the S-shaped rotating paddle moves upward at an angle tending to a plane, and the quartz sand turned over to the upper end of the S-shaped rotating paddle is lifted to the upper end. When the connecting ring moves downward for the second time, it drives the one-way gear to rotate 90° for the second time, and turns the quartz sand on the upper end of the rotating paddle to the other side, so that the quartz sand settled at the bottom of the stirring shell is fully turned over and cleaned.

[0028] Furthermore, the material dispensing mechanism includes a connecting ring 1 fixedly connected to a connecting rod 1, a plurality of rotating shafts are penetrated and rotatably installed inside the connecting ring 1, one end of the rotating shaft is fixedly connected to an S-shaped rotating paddle, the other end of the S-shaped rotating paddle is rotatably connected to a connecting ring 2, the connecting ring 2 is slidingly connected to a stirring paddle, a rotating gear is fixedly installed on the other end of the rotating shaft, a plurality of connecting shells are fixedly installed on the inner wall of the stirring shell, a plurality of square grooves 3 are provided inside the connecting shell, a one-way gear is fixedly installed on the surface of the square groove 3, and the rotating gear is meshed with the one-way gear.

[0029] Furthermore, the S-shaped rotating paddle is divided into a lower curved surface, a middle plane, and an upper curved surface, and the lower curved surface and the upper curved surface are respectively located at the two ends of the middle plane. When the S-shaped rotating paddle turns over the quartz sand that has sunk to the bottom of the stirring shell, the quartz sand is first flipped from the lower curved surface to the middle plane, and then flipped from the middle plane to one side of the upper curved surface, thereby completing the flipping and cleaning of the quartz sand that has sunk to the bottom of the stirring shell.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides a method for cleaning quartz sand for fracturing. The method drives a stirring paddle to rotate through a driving motor, thereby driving a bevel gear 1 to rotate. The bevel gear 1 drives two sets of bevel gears 2 to rotate. The bevel gear 2 drives a connecting column 1 to rotate. The connecting column 1 drives a rotating rod 1 to rotate along the connecting column 1 as the axis, thereby driving the rotating rod 2 and the connecting column 2 to slide in a square frame and driving the connecting frame to reciprocate up and down, so that the two sets of connecting columns 2 slide up and down in the U-shaped connecting rod, thereby driving the connecting rod 1 to move up and down. The connecting rod 1 drives the entire material-pickup mechanism to move downward during the descent process. The gear row is in meshing state, so that the rotating gear drives the rotating shaft and the S-shaped rotating paddle to rotate 90 degrees, and the quartz sand accumulated at the bottom of the stirring shell is turned over by the arc surface at the lower end of the S-shaped rotating paddle. When the connecting ring moves upward, under the action of the friction between the one-way gear and the rotating shaft and the connecting ring, the S-shaped rotating paddle moves upward at an angle tending to a plane, and the quartz sand turned to the upper end of the S-shaped rotating paddle is lifted to the upper end. When the connecting ring moves downward for the second time, it drives the one-way gear to rotate 90 degrees for the second time, and turns the quartz sand on the upper end of the rotating paddle to the other side, so that the quartz sand settled at the bottom of the stirring shell is fully turned over and cleaned. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the overall process structure of the present invention;

[0033] Figure 2 It is a schematic diagram of the overall structure of the scrubbing machine of the present invention;

[0034] Figure 3 It is a schematic diagram of the internal structure of the upper end of the scrubbing machine of the present invention;

[0035] Figure 4 It is a schematic diagram of the external structure of the scrubbing machine of the present invention;

[0036] Figure 5 It is a schematic diagram of the overall internal structure of the scrubbing machine of the present invention;

[0037] Figure 6 It is a three-dimensional structural schematic diagram of the transmission mechanism of the present invention;

[0038] Figure 7It is a schematic diagram of the three-dimensional structure of the transmission mechanism of the present invention;

[0039] Figure 8 It is a schematic diagram of the transmission mechanism and the material shifting mechanism of the present invention;

[0040] Fig. 9 It is a structural schematic diagram of the material shifting mechanism of the present invention;

[0041] Fig.10 It is a partial structural schematic diagram of the material shifting mechanism of the present invention;

[0042] Fig.11 It is a schematic diagram of the internal structure of the connection shell of the present invention.

[0043] In the figure: 1, scrubber; 11, stirring shell; 111, liquid inlet; 12, stirring device; 121, driving motor; 122, stirring paddle; 1221, bevel gear 1; 13, feed inlet; 14, support leg; 15, protective shell; 16, transmission mechanism; 161, bevel gear 2; 162, connecting column 1; 163, fixing plate; 164, U-shaped connecting rod; 1641, square groove 1; 165, connecting frame; 1651, square frame; 1652, connecting column 2; 165 3. Connecting plate; 1654. Connecting rod one; 1655. Square groove two; 166. Rotating rod one; 167. Rotating rod two; 168. Connecting column two; 17. Material shifting mechanism; 171. Connecting ring one; 172. Connecting ring two; 173. S-shaped rotating paddle; 1731. Lower curved surface; 1732. Middle plane; 1733. Upper curved surface; 174. Rotating shaft; 175. Rotating gear; 176. Connecting shell; 1761. Square groove three; 1762. One-way gear; 2. Feeding pipe. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings.

[0046] like Figure 1-11 As shown, a method for cleaning fracturing quartz sand comprises the following steps:

[0047] Step 1: Put the fracturing quartz sand to be cleaned into the scrubber for cleaning, add cleaning liquid into the scrubber, start the stirring device 12 to drive the transmission mechanism 16 and the material-dispensing mechanism 17 to move up and down, and clean the fracturing quartz sand in the scrubber for 30-60 minutes. The cleaning of the scrubber is divided into two stages; first, pour the quartz sand into the scrubber 1 through the feed pipe 2, and add the cleaning liquid to the liquid inlet 111; then start the stirring device 12 to stir and clean the quartz sand in the scrubber 1, and at the same time drive the bevel gear 1221 to rotate, and the bevel gear 1221 is driven by two sets of transmission mechanisms 16 during the rotation process, driving the material-dispensing mechanism 17 to move up and down; during stirring, the quartz sand is accumulated at the bottom of the scrubber 1 under the action of gravity, and the quartz sand is turned over under the rotation of the S-shaped rotating slurry 173 inside the material-dispensing mechanism 17;

[0048] The scrubbing machine 1 is composed of a stirring shell 11, a stirring device 12, a feed port 13, a supporting leg 14, a protective shell 15, a transmission mechanism 16, and a material-dispensing mechanism 17. A liquid inlet 111 is provided at the upper end of the stirring shell 11, and the liquid inlet 111 is communicated with the inside of the stirring shell 11. The feed port 13 is fixedly connected and communicated with the feed pipe 2. The protective shell 15 is fixedly connected with the stirring shell 11. The stirring device 12 includes a driving motor 121. A stirring paddle 122 is fixedly installed at the driving end of the driving motor 121. A bevel gear 1221 is fixedly installed on the outer side of the stirring paddle 122. The stirring paddle 122 penetrates the stirring shell 11 and is rotatably connected thereto. The stirring paddle 122 is driven to rotate by the driving motor 121 to stir the quartz sand inside the stirring shell 11. The quartz sand is stirred and cleaned, and the S-shaped rotating paddle 173 inside the material-dispensing mechanism 17 is used to turn the quartz sand; the stirring paddle 122 is driven to rotate by the driving motor 121, thereby driving the bevel gear 1221 to rotate, the bevel gear 1221 drives the two sets of bevel gears 161 to rotate, the bevel gear 161 drives the connecting column 162 to rotate, the connecting column 162 drives the rotating rod 166 to rotate along the connecting column 162 as the axis, thereby driving the rotating rod 167 and the connecting column 168 to slide in the square frame 1651 and driving the connecting frame 165 to reciprocate up and down, so that the two sets of connecting columns 1652 slide up and down in the U-shaped connecting rod 164, and the up and down movement of the material-dispensing mechanism 17 is realized;

[0049] The transmission mechanism 16 includes a bevel gear 161, which meshes with the bevel gear 1221. A connecting column 162 is fixedly installed on one side of the bevel gear 161. A fixing plate 163 is rotatably installed on the outer side of the connecting column 162. The lower end of the fixing plate 163 is fixedly connected to the stirring shell 11. A U-shaped connecting rod 164 is rotatably provided at one end of the connecting column 162. The lower end of the U-shaped connecting rod 164 is fixedly connected to the stirring shell 11. A square groove 1641 is penetrated in the middle of the U-shaped connecting rod 164. One end of the connecting column 162 penetrates the U-shaped connecting rod 164 and is fixedly installed with a rotating rod 166. The U-shaped connecting rod 1 A rotating rod 167 is rotatably mounted on one side away from the connecting column 162, one side of the rotating rod 167 is rotatably connected to the rotating rod 166, and a connecting column 168 is fixedly mounted on the other side of the rotating rod 167. A square frame 1651 is slidably mounted on the outer side of the connecting column 168, and a connecting frame 165 is arranged on the outer side of the square frame 1651. A square groove 1655 is penetrated and opened inside the connecting frame 165. The rotating rod 166 is fixedly connected to the surface of the square groove 1655. The square groove 1655 is the same size as the square groove 1641. Two groups of connecting columns 1652 are fixedly mounted on the lower end of the connecting frame 165. The two groups of connecting columns 1652 are fixedly mounted on the lower end of the connecting frame 165. The two connecting columns 1652 penetrate the U-shaped connecting rod 164 and are slidably connected thereto. The lower ends of the two groups of connecting columns 1652 penetrate the stirring shell 11 and are fixedly installed with connecting plates 1653. The connecting columns 1652 are slidably connected to the stirring shell 11. The lower ends of the connecting plates 1653 are fixedly installed with connecting rods 1654. The lower ends of the connecting rods 1654 are fixedly connected to the material-dispensing mechanism 17. The connecting rods 1654 drive the material-dispensing mechanism 17 to move downward as a whole during the descent process. Since the rotating gear 175 is in meshing state with the tooth row 1762, the rotating gear 175 drives the rotating shaft 174 and the S-shaped rotating paddle 173 to rotate 90°. The quartz sand accumulated at the bottom of the stirring shell 11 is turned over by the arc surface at the lower end of the S-shaped rotating paddle 173. When the connecting ring 171 moves upward, under the action of the friction between the one-way gear 1762, the rotating shaft 174 and the connecting ring 171, the S-shaped rotating paddle 173 moves upward at an angle tending to a plane, and the quartz sand turned to the upper end of the S-shaped rotating paddle 173 is lifted to the upper end. When the connecting ring 171 moves downward for the second time, the one-way gear 1762 is driven to rotate 90 degrees for the second time, and the quartz sand at the upper end of the rotating paddle 173 is turned over to the other side, so that the quartz sand settled at the bottom of the stirring shell 11 is fully turned over and cleaned.

[0050] The material dispensing mechanism 17 includes a connecting ring 171 fixedly connected to the connecting rod 1654, and a plurality of rotating shafts 174 are rotatably installed inside the connecting ring 171, one end of the rotating shaft 174 is fixedly connected to the S-shaped rotating paddle 173, and the other end of the S-shaped rotating paddle 173 is rotatably connected to the connecting ring 2 172, and the connecting ring 2 172 is slidably connected to the stirring paddle 122, and a rotating gear 175 is fixedly installed on the other end of the rotating shaft 174, and a plurality of connecting shells 176 are fixedly installed on the inner wall of the stirring shell 11, and a plurality of square grooves 1761 are provided inside the connecting shell 176, and the square grooves 1761 are provided inside the connecting shell 176. 1 is fixedly mounted with a one-way gear 1762, the rotating gear 175 is meshed with the one-way gear 1762, the S-shaped rotating paddle 173 is divided into a lower curved surface 1731, a middle plane 1732, and an upper curved surface 1733, the lower curved surface 1731 and the upper curved surface 1733 are respectively located at two ends of the middle plane 1732, when the S-shaped rotating paddle 173 turns over the quartz sand settled at the bottom of the stirring shell 11, the quartz sand is first turned over from the lower curved surface 1731 to the middle plane 1732, and then turned over from the middle plane 1732 to one side of the upper curved surface 1733, thereby completing the turning and cleaning of the quartz sand settled at the bottom of the stirring shell 11;

[0051] The scrubber can effectively remove clay, mud impurities and some fine-grained iron impurities on the surface of quartz sand. At the same time, during the scrubbing process, the particle size of quartz sand is adjusted and optimized to a certain extent to make its particle size distribution more uniform, so that the surface of quartz sand particles is fully cleaned and its purity and quality are improved. When cleaning begins, the stirring device starts to operate, driving the cleaning liquid and quartz sand to be fully mixed, and the cleaning liquid is poured into the scrubber. In this process, the hydroxide ions in the alkaline cleaning liquid react with the acidic oxide impurities, and the hydrogen ions in the acidic cleaning liquid react with the carbonate impurities. The surfactant reduces the surface tension and enhances the emulsification and dispersion of the dirt. The cleaning time is generally 15-30 minutes. After the cleaning is completed, water is added for secondary cleaning to prevent the residual substances in the cleaning liquid from reacting with the quartz sand impurities, such as the calcium and magnesium salts remaining after the acidic cleaning liquid cleans the carbonate impurities quartz sand, which crystallize on the surface of the quartz sand during subsequent drying. After scrubbing, the quality of quartz sand is significantly improved, so that it can meet higher standards of industrial application requirements.

[0052] Step 2: Pour the sludge generated during the cleaning process into a belt filter press for 15-30 minutes of extrusion treatment, and recycle the separated water; the belt filter press is used for sludge treatment, which can greatly reduce the water content of the sludge and reduce its volume, making it easier to transport and dispose of the sludge; the separated water can be recycled to improve water utilization.

[0053] Step 3: Transfer the cleaned fracturing quartz sand to the dewatering screen for dehydration. The dehydration time is 10-20 minutes. The dewatering screen can quickly and effectively reduce the water content in the quartz sand. For the dehydration operation of fracturing quartz sand with higher requirements, a dewatering screen with precise aperture and adjustable screen inclination is selected to ensure that most of the water can be separated from the quartz sand, so that the water content of the dehydrated quartz sand meets the requirements of subsequent treatment. The aperture of the screen is between 0.1-1 mm. For fracturing quartz sand with smaller particle size, a screen with an aperture of 0.1-0.3 mm can be selected; for quartz sand with slightly larger particle size, the aperture of the screen can be appropriately increased to 0.5-1 mm. The screen material is usually stainless steel or polyurethane. The stainless steel screen has higher strength and wear resistance, while the polyurethane screen has better flexibility and anti-clogging performance.

[0054] Step 4: The dehydrated fracturing quartz sand is transported to the conveyor and dried in a dryer for 30-60 minutes at a temperature of 150-250°C. The waste gas generated during the drying process enters the desulfurization tower for purification. The dryer can quickly and effectively reduce the water content in the quartz sand to a specified dryness level to meet the requirements of subsequent production processes or applications. During the drying process, sulfur dioxide in industrial waste gas is effectively absorbed and removed by chemical or physical methods to reduce the pollution of sulfur dioxide to the atmospheric environment. At the same time, other acidic gases, dust and impurities that may exist in the waste gas can be removed to achieve comprehensive gas purification.

[0055] Step 5: The dried fracturing quartz sand is screened through a square swing screen and graded according to particle size. The screening time is 20-40 minutes. The screened fracturing quartz sand enters the PLC automatic packaging machine for metering and packaging to complete the cleaning of the fracturing quartz sand. The square swing screen can perform high-precision grading and screening of quartz sand. According to different particle size requirements, the quartz sand can be accurately divided into multiple particle size levels. The multi-level fracturing quartz sand after screening is accurately measured and controlled by the PLC automatic packaging machine. The weight of each bag of quartz sand is ensured to meet the prescribed standards, reduce errors, achieve efficient and fast packaging operations, greatly improve packaging efficiency, and meet the needs of large-scale production.

[0056] It should be noted that, in the description of the present application, it should be understood that the terms "length", "thickness", "inside", "outside", "axial", "radial", etc., indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0057] In addition, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises", or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article, or apparatus.

[0058] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for cleaning fracturing quartz sand, characterized in that: The steps include: S1: Put the fracturing quartz sand to be cleaned into the scrubber for cleaning, add cleaning liquid into the scrubber, start the stirring device (12) to drive the transmission mechanism (16) and the material feeding mechanism (17) to move up and down, and clean the fracturing quartz sand in the scrubber for 30-60 minutes. The cleaning of the scrubber is divided into two stages; S2: Pour the sludge generated during the cleaning process into a belt filter press for 15-30 minutes of squeezing treatment, and recycle the separated water; S3: The cleaned fracturing quartz sand is transferred to a dewatering screen for dehydration, and the dehydration time is 10-20 minutes; S4: The dehydrated fracturing quartz sand is transported to the conveyor and dried in the dryer. The drying time is 30-60 minutes and the drying temperature is 150-250°C. The waste gas generated during the drying process enters the desulfurization tower for purification. S5: The dried fracturing quartz sand is screened by a square swing screen and classified according to the particle size. The screening time is 20-40 minutes. The screened fracturing quartz sand enters the PLC automatic packaging machine for metering and packaging, completing the cleaning of the fracturing quartz sand.

2. A method for cleaning fracturing quartz sand according to claim 1, characterized in that: The ratio of the cleaning fluid to the fracturing quartz sand is 2:

1.

3. The method for cleaning fracturing quartz sand according to claim 1, characterized in that: A surfactant is added to the cleaning solution, wherein the surfactant is one of sodium lauryl sulfate and polyoxyethylene ether, and the ratio of the surfactant to the cleaning solution is 1:

100.

4. The method for cleaning fracturing quartz sand according to claim 1, characterized in that: The specific steps of S1 are as follows: S11: First, quartz sand is poured into the scrubbing machine (1) through the feed pipe (2), and cleaning liquid is added to the liquid inlet (111); S12: Then the stirring device (12) is started to stir and clean the quartz sand in the scrubbing machine (1), and at the same time, the bevel gear 1 (1221) is driven to rotate. During the rotation process, the bevel gear 1 (1221) is driven by two sets of transmission mechanisms (16) to drive the material shifting mechanism (17) to move up and down; S13: During the stirring, the quartz sand is accumulated at the bottom of the scrubbing machine (1) under the action of gravity, and the quartz sand is turned over by the rotation of the S-shaped rotating paddle (173) inside the material-dispensing mechanism (17).

5. A method for cleaning fracturing quartz sand according to claim 4, characterized in that: The scrubbing machine (1) comprises a stirring shell (11), a stirring device (12), a feed port (13), a supporting leg (14), a protective shell (15), a transmission mechanism (16), and a material dispensing mechanism (17). A liquid inlet (111) is provided at the upper end of the stirring shell (11), the liquid inlet (111) is communicated with the inside of the stirring shell (11), the feed port (13) is fixedly connected and communicated with a feed pipe (2), the protective shell (15) is fixedly connected with the stirring shell (11), the stirring device (12) comprises a driving motor (121), a stirring paddle (122) is fixedly mounted on the driving end of the driving motor (121), a bevel gear (1221) is fixedly mounted on the outer side of the stirring paddle (122), and the stirring paddle (122) passes through the stirring shell (11) and is rotatably connected thereto.

6. A method for cleaning fracturing quartz sand according to claim 4, characterized in that: The specific steps of S12 are as follows: The driving motor (121) drives the stirring paddle (122) to rotate, thereby driving the bevel gear 1 (1221) to rotate, and the bevel gear 1 (1221) drives the two sets of bevel gear 2 (161) to rotate, and the bevel gear 2 (161) drives the connecting column 1 (162) to rotate, and the connecting column 1 (162) drives the rotating rod 1 (166) to rotate along the connecting column 1 (162) as the axis, thereby driving the rotating rod 2 (167) and the connecting column 2 (168) to slide in the square frame (1651) and drive the connecting frame (165) to reciprocate up and down, so that the two sets of connecting columns 2 (1652) slide up and down in the U-shaped connecting rod (164), thereby realizing the up and down movement of the material diverting mechanism (17).

7. A method for cleaning fracturing quartz sand according to claim 6, characterized in that: The transmission mechanism (16) comprises a second bevel gear (161), the second bevel gear (161) meshing with a first bevel gear (1221), a connecting column (162) fixedly mounted on one side of the second bevel gear (161), a fixing plate (163) rotatably mounted on the outer side of the connecting column (162), the lower end of the fixing plate (163) being fixedly connected to the stirring shell (11), a U-shaped connecting rod (164) rotatably mounted on one end of the connecting column (162), the U-shaped connecting rod (164) The lower end is fixedly connected to the stirring shell (11); a square groove (1641) is penetrated through the middle of the U-shaped connecting rod (164); one end of the connecting column (162) penetrates the U-shaped connecting rod (164) and is fixedly installed with a rotating rod (166); a rotating rod (167) is rotatably installed on the side of the U-shaped connecting rod (164) away from the connecting column (162); one side of the rotating rod (167) is rotatably connected to the rotating rod (166); and the other side of the rotating rod (167) is A second connecting column (168) is fixedly installed, a square frame (1651) is slidably arranged on the outer side of the second connecting column (168), a connecting frame (165) is arranged on the outer side of the square frame (1651), a second square groove (1655) is penetrated through the interior of the connecting frame (165), a rotating rod (166) is fixedly connected to the surface of the second square groove (1655), the second square groove (1655) is the same size as the first square groove (1641), and two sets of connecting rods are fixedly installed at the lower end of the connecting frame (165). Column 2 (1652), two groups of connecting column 2 (1652) both penetrate the U-shaped connecting rod (164) and are slidably connected thereto, the lower ends of the two groups of connecting column 2 (1652) both penetrate the stirring shell (11) and are fixedly installed with a connecting plate (1653), the connecting column 2 (1652) is slidably connected to the stirring shell (11), the lower end of the connecting plate (1653) is fixedly installed with a connecting rod 1 (1654), and the lower end of the connecting rod 1 (1654) is fixedly connected to the material dispensing mechanism (17).

8. A method for cleaning fracturing quartz sand according to claim 4, characterized in that: The specific steps of S13 are as follows: The connecting rod 1 (1654) drives the material-dispensing mechanism (17) to move downward as a whole during the descending process. Since the rotating gear (175) is in meshing state with the tooth row (1762), the rotating gear (175) drives the rotating shaft (174) and the S-shaped rotating paddle (173) to rotate 90 degrees. The quartz sand accumulated at the bottom of the stirring shell (11) is turned over by the arc surface at the lower end of the S-shaped rotating paddle (173). When the connecting ring 1 (171) moves upward, the one-way gear (1762) ) and the friction between the rotating shaft (174) and the connecting ring (171), the S-shaped rotating paddle (173) moves upward at an angle tending to a plane, and the quartz sand flipped to the upper end of the S-shaped rotating paddle (173) is lifted to the upper end. When the connecting ring (171) moves downward for the second time, the one-way gear (1762) is driven to rotate 90 degrees for the second time, and the quartz sand on the upper end of the rotating paddle (173) is flipped to the other side, so that the quartz sand settled on the bottom of the stirring shell (11) is fully flipped and cleaned.

9. A method for cleaning fracturing quartz sand according to claim 8, characterized in that: The material shifting mechanism (17) comprises a connecting ring 1 (171) fixedly connected to a connecting rod 1 (1654); a plurality of rotating shafts (174) are penetrated and rotatably mounted inside the connecting ring 1 (171); one end of the rotating shaft (174) is fixedly connected to an S-shaped rotating paddle (173); the other end of the S-shaped rotating paddle (173) is rotatably connected to a connecting ring 2 (172); the connecting ring 2 (172) is slidably connected to a stirring paddle (122); a rotating gear (175) is fixedly mounted on the other end of the rotating shaft (174); a plurality of connecting shells (176) are fixedly mounted on the inner wall of the stirring shell (11); a plurality of square grooves 3 (1761) are provided inside the connecting shell (176); a one-way gear (1762) is fixedly mounted on the surface of the square grooves 3 (1761); and the rotating gear (175) meshes with the one-way gear (1762).

10. A method for cleaning fracturing quartz sand according to claim 9, characterized in that: The S-shaped rotating paddle (173) is divided into a lower curved surface (1731), a middle plane (1732), and an upper curved surface (1733). The lower curved surface (1731) and the upper curved surface (1733) are respectively located at two ends of the middle plane (1732). When the S-shaped rotating paddle (173) turns over the quartz sand that has settled on the bottom of the stirring shell (11), the quartz sand is first turned over from the lower curved surface (1731) to the middle plane (1732), and then turned over from the middle plane (1732) to one side of the upper curved surface (1733), thereby completing the turning and cleaning of the quartz sand that has settled on the bottom of the stirring shell (11).

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