Oil and impurity removal treatment process for oilfield reinjection water

Abstract

The invention discloses an oil and impurity removal treatment process for oilfield reinjection water, and belongs to the technical field of wastewater treatment.The treatment equipment adopted by the treatment process comprises a treatment tank, a drainage pipe is arranged on the side wall of the treatment tank, an oil discharge pipe is arranged at the top of the treatment tank, a mud discharge pipe is arranged at the bottom of the treatment tank, and a centrifugal tank is arranged in the treatment tank; a liquid supply box is arranged on the side wall of the centrifugal tank, an oil discharge tank is arranged at the top of the centrifugal tank and fixedly connected with the treatment tank, a sewage discharge tank is arranged at the bottom of the centrifugal tank, and a water inlet pipe extending into the centrifugal tank is arranged on the side wall of the treatment tank. Through the design of the driving blade and the first sliding block, when water flow in the centrifugal tank, the pollution discharge tank and the oil discharge tank is guided to rotate, the driving blade continuously and automatically cleans the inner side wall of the centrifugal tank in a water inlet area, and oil liquid and impurity deposition is avoided; and through cooperation of the first sliding block and the first magnetic block, the first sliding block reciprocates to automatically clean oil stains on the surface of the driving blade.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a process for removing oil and impurities from oilfield reinjection water. Background Art

[0002] Oilfield reinjection water refers to the water separated from the produced crude oil after treatment, which is re-injected into the underground oil layer, so as to maintain the formation pressure after extraction, ensure the stability of subsequent extraction, and improve safety and recovery rate. The separated reinjection water needs to be deoiled and decontaminated before it can be reinjected. The purpose of treatment is to prevent the oil and impurities in the water from clogging the formation pores, affecting the water injection effect and oil well production capacity, and can also reduce the pollution of groundwater resources and the environment by the reinjection water.

[0003] At present, the reinjection water of oil fields is mainly treated by a cyclone diverter for rapid oil and impurity removal. By applying centrifugal force, the light phase oil and heavy phase impurities are made to float and sink respectively, thereby achieving rapid oil and impurity removal. However, when the prior art uses a cyclone diverter to remove oil and impurities from the reinjection water, since the reinjection water contains oil, when the reinjection water is injected from a specific position and angle inside the separation device for a long time, the oil in the water impacts and contacts with the inner wall of the device, causing the oil in the reinjection water to gradually accumulate near this area under the action of the inner wall of the device, so that an oil film is formed on the inner wall of the device, which is not only easy to absorb the oil in the water and affect the oil removal effect, but the attached oil is also easy to re-mix into the water in the subsequent process to cause secondary pollution, which not only affects the treatment efficiency of the reinjection water, but also leads to more frequent maintenance and cleaning, increasing operating costs.

[0004] How to invent an oilfield reinjection water deoiling and impurity removal process to improve these problems has become an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0005] In order to make up for the above deficiencies, the present invention provides a process for removing oil and impurities from oilfield reinjection water, aiming to improve the problems raised by the prior art.

[0006] The present invention is achieved in that: The present invention provides a process for removing oil and impurities from oilfield reinjection water. The processing equipment used in the process includes a processing tank, a drainage pipe is arranged on the side wall of the processing tank, an oil drainage pipe is arranged on the top of the processing tank, a mud drainage pipe is arranged on the bottom of the processing tank, a centrifugal tank is arranged inside the processing tank, a liquid supply box is arranged on the side wall of the centrifugal tank, an oil drainage tank is arranged on the top of the centrifugal tank, the oil drainage tank is fixedly connected with the processing tank, a sewage tank is arranged on the bottom of the centrifugal tank, a water inlet pipe extending to the inside of the centrifugal tank is arranged on the side wall of the processing tank, a cleaning mechanism is arranged inside the centrifugal tank, and the cleaning mechanism includes a centrifugal tank arranged on the side wall of the processing tank. A sealing ring on the side wall of the tank, a swivel one is rotatably connected inside the sealing ring, a driving blade is provided on the swivel one, the driving blade extends to the inside of the sewage tank and the oil drain tank, and the driving blade is in contact with the inner side walls of the centrifugal tank, the sewage tank and the oil drain tank, a slider one is slidably connected to the side wall of the driving blade, the slider one is provided with a magnetic block six in contact with the inner side wall of the centrifugal tank, a magnetic block one matching the magnetic block six is ​​provided on the outer side wall of the centrifugal tank, a filtering mechanism for further removing impurities from the oil-water mixture entering the oil drain tank is provided inside the oil drain tank, and a spray mechanism for assisting the removal of impurities from the reinjection water is provided inside the swivel one; The treatment process includes the following steps: S1: Inject reinjection water into the centrifugal tank through the water inlet pipe. The reinjection water rotates inside the centrifugal tank. Under the action of centrifugal force, the light phase oil floats up into the oil drain tank, and the heavy phase impurities sink into the sewage tank; S2: After the light phase oil enters the oil drain tank, the centrifugal force increases, and the oil mixture is further separated and impurities are removed. The separated oil continues to float up and is sucked out through the oil drain pipe; S3: After the heavy phase mixture enters the sewage tank, it settles to the bottom of the treatment tank under the action of centrifugal force and gravity and is discharged through the mud discharge pipe.

[0007] Preferably, the inner diameters of the oil drain tank, centrifugal tank and sewage tank decrease successively, the inner wall of the sewage tank is rotatably connected with a swivel ring 2, the swivel ring 2 is connected to the driving blade, and a stirring blade coaxial with the swivel ring 2 is arranged at the bottom of the swivel ring 2.

[0008] Preferably, the top of the slider 1 is provided with an oblique angle toward the driving blade.

[0009] Preferably, the magnetic block 1 is in the form of a single closed loop on the outer wall of the centrifuge tank. Starting from the lowest point, the magnetic block 1 gradually rises one grid to reach the highest point, and then descends from the highest point to the lowest point in a grid-by-grid manner, forming a distribution pattern with a single undulation and connected end to end.

[0010] Preferably, the liquid spraying mechanism comprises a slider four slidably connected to the inside of the rotating ring one, a liquid supply box is arranged on the outer wall of the centrifuge tank, a flocculant is arranged inside the liquid supply box, a medicine tube is connected to the bottom of the liquid supply box, a spring is arranged between the slider four and the inside of the rotating ring one, a piston protrusion which is in contact with the inner wall of the rotating ring one is arranged on the outer wall of the rotating ring one, a liquid inlet and a liquid discharge port are arranged at the bottom of the rotating ring one, the liquid inlet is close to the slider four, the outlet of the medicine tube extends to the inside of the rotating ring one and is close to the liquid inlet, and the medicine tube and the liquid inlet are located on the same side of the slider four, and the liquid discharge port is located on the other side of the slider four, and the inner wall of the centrifuge tank is provided with a nozzle of a height and number corresponding to the highest position of the magnetic block one, and the nozzle and the liquid discharge port are connected.

[0011] Preferably, the filtering mechanism comprises a swivel three rotatably connected to the oil drain tank, the swivel three is connected to the driving blade, the interior of the swivel three is provided with a sealing chamber one and a sealing chamber two, the interior of the sealing chamber two is sleeved with a piston rod, the bottom of the piston rod extends to the outside of the swivel three and the bottom of the piston rod is connected to a filter screen one, the top of the filter screen one is provided with a filter screen two, a spring one is provided between the filter screen one and the filter screen two, the top of the swivel three is rotatably connected to a blade group, the rotating shaft of the blade group is also connected to a convex shaft, and the interior of the swivel three is provided with a spring that is opposite to the convex shaft A piston block 2 should be set, the interior of the sealing chamber 1 is sleeved with the piston block 1, a spring 2 is set between the piston block 1 and the sealing chamber 1, a liquid supply pipe is set between the sealing chamber 1 and the sealing chamber 2, a pressure relief port is opened on the side wall of the sealing chamber 2, the interior of the swivel 3 is sleeved with a slider 3 corresponding to the liquid supply pipe, the interior of the swivel 3 is sleeved with a slider 2 corresponding to the pressure relief port, the interior of the swivel 3 is sleeved with a shielding cylinder corresponding to the blade group, a magnetic block 3 is set at the bottom of the swivel 3, and a magnetic block 2 corresponding to the magnetic block 3 is set on the top of the filter screen 2.

[0012] Preferably, both ends of slider three and slider two are designed with magnets, the top and bottom of the inner cavity of sealed chamber one are provided with magnetic block five corresponding to slider three, and the top and bottom of the inner cavity of sealed chamber two are provided with magnetic block four corresponding to slider two, a magnet is provided at the top of the piston rod, and the piston rod is designed to cooperate with magnetic block four.

[0013] Preferably, the shielding cylinder is provided with a connecting groove matching the blade assembly, a spring three is provided between the inner side of the shielding cylinder and the rotating ring three, and a push rod extending into the interior of the sealing chamber two is provided at the bottom of the shielding cylinder.

[0014] Preferably, a raised filter screen is provided in the middle of filter screen two, the raised filter screen is spirally designed, a notch matching the raised filter screen is provided on the surface of filter screen one, and filter screens one and filter screen two are connected through the notch.

[0015] In summary, the beneficial effects of the present invention are: 1. Through the design of the driving blades and the slider 1, when guiding the internal water flow of the centrifugal tank, the sewage tank and the oil discharge tank to rotate, the driving blades continuously and automatically clean the inner wall of the centrifugal tank in the water inlet area to avoid the deposition of oil and impurities. Through the cooperation of the slider 1 and the magnetic block 1, the slider 1 reciprocates to automatically clean the oil on the surface of the driving blade. At the same time, in conjunction with the spray mechanism, the piston protrusion continuously impacts the slider 1 and the driving blade that have run to the highest point with the mixed liquid of water and flocculant, further reducing the accumulation of oil and impurities after cleaning, reducing the influence of residual oil on subsequent oil-impurity separation and erosion and damage to the centrifugal tank, improving service life, extending maintenance cycle and reducing maintenance cost. After the impact of the mixed flocculant solvent and the driving blade, a stronger disturbance will be generated, which improves the dispersion effect of the flocculant, improves the contact effect with impurity particles, improves the flocculation reaction efficiency and the separation and removal efficiency of impurities in the reinjection water.

[0016] 2. The oil-impurity mixture that has been initially separated increases the frequency of friction and collision through the rotation cooperation with the raised filter screen, realizes dynamic separation and filtration, accelerates the separation of oil and impurities, realizes further separation and impurity removal of oil, and improves the efficiency and quality of oil-impurity separation. At the same time, when the raised filter screen becomes congested and the fluidity becomes low, the filter screen 1 can be driven to move up through the change of fluidity and the change of buoyancy and force, and the filter screen 1 can be reset through the accumulation and release of spring 2. During the resetting process, the side wall of the raised filter screen is automatically cleaned by filter screen 1, realizing a self-cleaning effect, effectively ensuring the efficiency and operation stability of further filtering and impurity removal of the oil after initial separation, and improving the efficiency and quality of oil and impurity removal of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the interior of a processing tank provided in an embodiment of the present invention.

[0019] Figure 2 It is a schematic diagram of the interior of a centrifugal tank, a sewage tank and an oil discharge tank provided in an embodiment of the present invention.

[0020] Figure 3 It is a schematic diagram of overall disassembly provided by an embodiment of the present invention.

[0021] Figure 4 It is a schematic diagram of the interior of a centrifuge tank provided in an embodiment of the present invention.

[0022] Figure 5 It is a schematic diagram of the interior of a swivel provided in an embodiment of the present invention.

[0023] Figure 6 It is a schematic diagram of a driving blade and a slider provided in an embodiment of the present invention.

[0024] Figure 7 It is a schematic diagram of the distribution of a slider 1 and a magnetic block 1 provided in an embodiment of the present invention.

[0025] Figure 8 It is an overall schematic diagram of the swivel three provided in an embodiment of the present invention.

[0026] Fig. 9 It is a schematic diagram of the combination of filter screen 1 and filter screen 2 provided in an embodiment of the present invention.

[0027] Fig.10 It is a schematic diagram of the interior of swivel three provided in an embodiment of the present invention.

[0028] Fig.11 It is an overall schematic diagram of the shielding tube provided in an embodiment of the present invention.

[0029] Legend: 100, treatment tank; 101, water inlet pipe; 102, drainage pipe; 103, mud discharge pipe; 104, oil discharge pipe; 200, centrifugal tank; 201, driving blade; 202, sealing ring; 203, swivel one; 204, liquid supply box; 205, slider one; 206, magnetic block one; 207, reagent tube; 208, slider four; 209, piston bump; 210, liquid inlet; 211, liquid discharge port; 212, nozzle; 213, magnetic block six; 300, sewage tank; 301, stirring blade; 302, swivel two; 400, oil discharge tank; 401, swivel Ring three; 402, filter screen one; 403, filter screen two; 404, spring one; 405, raised filter screen; 406, magnet block two; 407, piston rod; 408, shielding tube; 409, slider two; 410, magnet block three; 411, magnet block four; 412, pressure relief port; 413, slider three; 414, liquid supply pipe; 415, magnet block five; 416, piston block one; 417, spring two; 418, piston block two; 419, convex shaft; 420, blade group; 421, sealing chamber one; 422, sealing chamber two; 423, connecting groove; 424, spring three. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Reference Figure 1-11 The present invention provides a process for removing oil and impurities from reinjected water in an oil field. The processing equipment used in the process includes a processing tank 100, a drainage pipe 102 is arranged on the side wall of the processing tank 100, an oil drainage pipe 104 is arranged on the top of the processing tank 100, a mud drainage pipe 103 is arranged on the bottom of the processing tank 100, a centrifugal tank 200 is arranged inside the processing tank 100, a liquid supply box 204 is arranged on the side wall of the centrifugal tank 200, and the liquid supply box 204 is also provided with a group of hoses extending to the outside of the processing tank 100 for liquid supply, an oil drainage tank 400 is arranged on the top of the centrifugal tank 200, and the oil drainage tank 400 is fixedly connected to the processing tank 100, a sewage tank 300 is arranged at the bottom of the centrifugal tank 200, a water inlet pipe 101 extending to the inside of the centrifugal tank 200 is arranged on the side wall of the processing tank 100, and a cleaning mechanism is arranged inside the centrifugal tank 200. The processing mechanism includes a sealing ring 202 arranged on the side wall of the centrifugal tank 200, the sealing ring 202 is rotatably connected with a swivel 203 inside, the swivel 203 is provided with a driving blade 201, the driving blade 201 extends to the inside of the sewage tank 300 and the oil drain tank 400, and the driving blade 201 is fitted with the inner side walls of the centrifugal tank 200, the sewage tank 300 and the oil drain tank 400, the side wall of the driving blade 201 is slidably connected with a slider 205, the slider 205 is provided with a magnetic block 6 213 fitted with the inner side wall of the centrifugal tank 200, the outer side wall of the centrifugal tank 200 is provided with a magnetic block 206 matched with the magnetic block 6 213, the inside of the oil drain tank 400 is provided with a filtering mechanism for further removing impurities from the oil-water mixture entering the oil drain tank 400, and the inside of the swivel 203 is provided with a spray mechanism for auxiliary reinjection water impurity removal; The treatment process includes the following steps: S1: Inject reinjection water into the centrifugal tank 200 through the water inlet pipe 101. The reinjection water rotates inside the centrifugal tank 200. Under the action of centrifugal force, the light phase oil floats up into the oil drain tank 400, and the heavy phase impurities sink into the sewage tank 300; S2: After the light phase oil enters the oil drain tank 400, the centrifugal force increases, and the oil mixture is further separated and impurities are removed. The separated oil continues to float up and is sucked out through the oil drain pipe 104; S3: After the heavy phase mixture enters the sewage tank 300, it settles to the bottom of the treatment tank 100 under the action of centrifugal force and gravity, and is discharged through the mud discharge pipe 103.

[0032] It should be noted that the inner diameters of the oil drain tank 400, the centrifugal tank 200 and the sewage tank 300 decrease successively, and the inner wall of the sewage tank 300 is rotatably connected with a swivel 2 302, the swivel 2 302 is connected to the driving blade 201, and the bottom of the swivel 2 302 is provided with a stirring blade 301 coaxial with the swivel 2 302.

[0033] Furthermore, the top of the slider 205 is provided with an oblique angle toward the driving blade 201. It should be noted that, through the inverted angle, the oil attached to the surface of the driving blade 201 can be scraped off and guided when the slider 205 moves, so that it slides down along the inverted angle, thereby reducing oil accumulation and improving the self-cleaning effect.

[0034] Furthermore, the magnetic block 206 is in the form of a single closed loop on the outer wall of the centrifuge tank 200. Starting from the lowest point, the magnetic block 206 gradually rises one grid to reach the highest point, and then descends from the highest point to the lowest point one grid at a time, forming a distribution pattern with a single undulation and connected end to end. It should be noted that there are multiple groups of magnetic blocks 206 arranged at the highest point and they are flush. This design is for when the piston protrusion 209 passes through the slider four 208, the piston protrusion 209 and the slider four 208 cannot form a closed pressure mechanism and cannot spray liquid through the nozzle 212. Therefore, the design of multiple groups of magnetic blocks 206 is extended. When the piston protrusion 209 passes the slider four 208 and starts to squeeze and spray liquid, the slider 205 that has previously passed the highest magnetic block 206 is compensated for by the multiple groups of flush magnetic blocks 206 and the nozzle 212, thereby avoiding a blind spot for liquid spraying.

[0035] Reference Figure 2-6 The liquid spraying mechanism includes a slider 208 slidably connected to the inside of the rotating ring 203, a liquid supply box 204 is arranged on the outer wall of the centrifugal tank 200, a flocculant is arranged inside the liquid supply box 204, a medicine tube 207 is connected to the bottom of the liquid supply box 204, a spring is arranged between the slider 208 and the inside of the rotating ring 203, a piston protrusion 209 which is in contact with the inner wall of the rotating ring 203 is arranged on the outer wall of the rotating ring 203, a liquid inlet 210 and a liquid outlet 211 are arranged at the bottom of the rotating ring 203, the liquid inlet 210 is close to the slider 208, and the outlet of the medicine tube 207 extends to the rotating ring 203. The interior of the ring 1 203 is close to the liquid inlet 210, and the medicine tube 207 and the liquid inlet 210 are located on the same side of the slider 4 208, and the discharge port 211 is located on the other side of the slider 4 208. The inner wall of the centrifuge tank 200 is provided with a nozzle 212 of a height and number corresponding to the highest position of the magnetic block 1 206, and the nozzle 212 is connected to the discharge port 211. It should be noted that the medicine tube 207 and the liquid inlet 210 are provided with a one-way valve for absorbing external liquid under negative pressure, and the inside of the discharge port 211 is provided with a one-way valve for pumping out the liquid inside the rotating ring 1 203 under positive pressure.

[0036] Reference Figure 8-11 The filtering mechanism includes a swivel 401 rotatably connected to the oil drain tank 400, the swivel 401 is connected to the driving blade 201, the swivel 401 has a sealing chamber 1 421 and a sealing chamber 2 422, the sealing chamber 2 422 has a piston rod 407 sleeved therein, the bottom of the piston rod 407 extends to the outside of the swivel 401, and the bottom of the piston rod 407 is connected to a filter screen 1 402, the top of the filter screen 1 402 is provided with a filter screen 2 403, the filter screen 1 402 and the filter screen 2 403 are connected to each other, and the filter screen 1 402 and the filter screen 2 403 are connected to each other. 3, a spring 1 404 is arranged between the swivel 3, a blade group 420 is rotatably connected to the top of the swivel 3 401, the axis of the blade group 420 shaft points to the axis direction of the oil drain tank 400, the shaft of the blade group 420 is also connected to the cam 419, a piston block 2 418 corresponding to the cam 419 is arranged inside the swivel 3 401, a spring is arranged between the piston block 1 416 and the swivel 3 401, the piston block 2 418 and the cam 419 form a cam piston mechanism, and the position inside the swivel 3 401 A set of one-way liquid pipes is arranged below the piston block 418 to circulate and pump the liquid into the sealed chamber 421. The swivel ring 401 is also provided with a one-way liquid pipe to circulate and suck the liquid in the processing tank 100 into the sealed chamber 421 for the piston block 418. The sealed chamber 421 is sleeved with the piston block 416. A spring 417 is arranged between the piston block 416 and the sealed chamber 421. A liquid supply valve with a one-way valve is arranged between the sealed chamber 421 and the sealed chamber 422. Tube 414, a pressure relief port 412 with a one-way valve is provided on the side wall of the sealing chamber 2 422, a slider 3 413 corresponding to the liquid supply tube 414 is sleeved inside the swivel 3 401, a slider 2 409 corresponding to the pressure relief port 412 is sleeved inside the swivel 3 401, a shielding cylinder 408 corresponding to the blade group 420 is sleeved inside the swivel 3 401, a magnetic block 3 410 is arranged at the bottom of the swivel 3 401, and a magnetic block 2 406 corresponding to the magnetic block 3 410 is arranged on the top of the filter screen 2 403.

[0037] It should be noted that both ends of slider three 413 and slider two 409 are designed with magnets, the top and bottom of the inner cavity of sealed chamber one 421 are provided with magnetic block five 415 corresponding to slider three 413, and the top and bottom of the inner cavity of sealed chamber two 422 are provided with magnetic block four 411 corresponding to slider two 409, and a magnet is provided at the top of the piston rod 407, and the piston rod 407 is designed in coordination with the magnetic block four 411.

[0038] Reference Fig.11 The shielding cylinder 408 is provided with a connecting groove 423 matching the blade group 420, a spring three 424 is arranged between the inner side of the shielding cylinder 408 and the rotating ring three 401, and a push rod extending to the inside of the sealing chamber two 422 is arranged at the bottom of the shielding cylinder 408.

[0039] Reference Fig. 9 A raised filter 405 is provided in the middle of the filter 2 403 , and the raised filter 405 is of spiral design. A notch matching the raised filter 405 is provided on the surface of the filter 1 402 , and the filter 1 402 and the filter 1 402 are connected through the notch.

[0040] The workflow of this oilfield reinjection water deoiling and impurity removal process is as follows: First, the reinjection water is pumped into the interior of the centrifugal tank 200 through the water inlet pipe 101 by the pump machine arranged outside. When the water flows into the interior of the centrifugal tank 200, the inclined design of the driving blade 201 can generate thrust, drive the driving blade 201 to rotate, and further drive the swivel 1 203, the stirring blade 301, and the swivel 3 401 to rotate synchronously. Through the synchronous rotation of the stirring blade 301 and the driving blade 201, the water flows inside the centrifugal tank 200, the sewage tank 300 and the oil tank 400 can be rotated synchronously. Under the centrifugal action, the centrifugal forces on the materials with different densities are different. The heavy phase impurities are thrown to the inner wall of the centrifugal tank 200 and move down along the inner wall of the centrifugal tank 200, while the light phase fluid gathers toward the center of the centrifugal tank 200 and forms an inner vortex to move upward. In this process, during the rotation of the driving blade 201, the impurities and oil stains attached to the inner wall of the centrifugal tank 200 can be scraped and cleaned through the fit between the driving blade 201 and the inner wall of the centrifugal tank 200, so that the centrifugal tank 200 can be cleaned. The oil and impurities attached to the inner wall of the centrifugal tank 200 fall off and enter the liquid flow to be separated, and the remaining oil accumulates on the surface of the driving blade 201 as the driving blade 201 rotates. At the same time, when the driving blade 201 rotates, the slider 205 on the side wall of the driving blade 201 is attracted by the magnetic force of the magnetic block 6 213 and the magnetic block 1 206. According to the distribution position characteristics of the magnetic block 1 206, the slider 1 205 gradually rises at the beginning, stays for a period of time after rising to the highest point, and then descends along the driving blade 201, and continues to rise after descending to the lowest point, and then continues this cycle. During this cycle, the oil and impurities attached to the surface of the driving blade 201 are cleaned by the automatic lifting and lowering of the slider 1 205. The oil attached to the driving blade 201 from the side wall of the centrifugal tank 200 only needs to be cleaned by the movement of the slider 1 205. Part of the oil gathers and adheres as the slider 1 205 moves and cleans, and the other part enters the liquid flow inside the centrifugal tank 200 after being cleaned and centrifugally separated.

[0041] When the driving blade 201 rotates, the rotating ring 203 rotates synchronously. When the rotating ring 203 rotates, the piston protrusion 209 rotates synchronously. Since the slider 4 208 is in contact with the side wall of the rotating ring 203, as the piston protrusion 209 moves, the pressure between the piston protrusion 209 and the liquid inlet 210 and the reagent tube 207 is reduced, and the flocculant in the liquid supply box 204 and the separated water in the treatment tank 100 are sucked into the inner cavity of the sealing ring 202 through the one-way valve inside the reagent tube 207 and the liquid inlet 210. At the same time, as the piston protrusion 209 moves, the piston protrusion The pressure between the sealing ring 202 and the drain port 211 increases, and the water flow and the flocculant mixed solvent in the sealing ring 202 are sprayed out through the nozzle 212 to impact the top and bottom of the slider 205 that has moved to the highest point. The impact of the pressurized liquid flow can impact the residual oil and impurities in the upward and downward cleaning process of the slider 205, so as to further clean the slider 205 and the driving blade 201, further reduce the accumulation of oil and impurities on the surface of the driving blade 201 and the slider 205 after cleaning, and enhance the self-cleaning effect of the driving blade 201 and the slider 205, thereby maintaining the cleaning effect. The effect of removing oil stains attached to the inner wall of the centrifugal tank 200 is proved, the long-term stable operation of the centrifugal tank 200 is ensured, the influence of residual oil stains on the subsequent oil-impurity separation and the erosion and damage to the centrifugal tank 200 are reduced, the service life is improved, the maintenance cycle is extended and the maintenance cost is reduced; at the same time, the mixed flocculant solvent is mixed with the driving blade 201 after impact, and a stronger disturbance can be generated through the impact of the flocculant and the driving blade 201. For the solution containing more impurities or a larger colloid density close to the inner wall of the centrifugal tank 200 under the centrifugal action, not only the flocculant dispersion effect is stronger, but also the impurities are separated. The stronger the contact effect with the particles, the higher the flocculation reaction efficiency, and the higher the separation and removal efficiency of impurities in the reinjected water. When the piston lug 209 rotates to pass through the slider four 208, the slider four 208 is pushed away from the contact with the swivel ring 203 through the inclined design of the side of the slider four 208 when the piston lug 209 passes. After the piston lug 209 passes through the slider four 208, the slider four 208 is reset under the action of the spring between the slider four 208 and the sealing ring 202. At this time, as the swivel ring 203 and the piston lug 209 continue to rotate, the device circulates to absorb liquid and circulates the pump liquid through the nozzle 212.

[0042] After the initial separation of the oil after centrifugation, it floats up into the oil drain tank 400 and contacts with the filter screen 1 402, the filter screen 2 403 and the raised filter screen 405. With the synchronous rotation of the swivel ring 3 401, the filter screen 1 402, the filter screen 2 403 and the raised filter screen 405 rotate synchronously. In the initial state, under the elastic restraint of the spring 1 404, the filter screen 1 402 and the filter screen 2 403 are close to each other, and the raised filter screen 405 extends through the bottom of the filter screen 1 402. After the initial separation of the oil contacts with the raised filter screen 405, with the continuous rotation of the filter screen 1 402 and the raised filter screen 405, part of the oil is filtered by the raised filter screen 405 and the filter screen 1 402 and then floats up, and is finally returned through the oil drain pipe 104. The oil particles are collected, while some of the oil containing impurity particles will be blocked by the filter screen 402 and the raised filter screen 405. With the rotation of the raised filter screen 405 and the spiral design of the raised filter screen 405, the oil particles will be subjected to centrifugal force and will also drive the oil in the gap of the raised filter screen 405 to be continuously thrown out in the direction away from the center of the raised filter screen 405. At this time, due to the continuous friction and collision between the oil and the raised filter screen 405, dynamic separation and filtration are realized, which accelerates the separation of the oil and impurities, so that the oil floats up and is collected after filtration, and the impurities in the oil are separated after further filtration and thrown to the outer wall of the oil drain tank 400 under the action of centrifugal force and gravity, and then settle and are collected under the action of gravity.

[0043] When the raised filter screen 405 has been working for a long time, the side wall of the raised filter screen 405 becomes congested and clogged with impurities, and the permeability of the raised filter screen 405 is reduced, resulting in the accumulation of oil and dirt in the raised filter screen 405 and the filter screen 1 402 area, and the buoyancy thrust of the filter screen 1 402 increases. At the same time, due to the lower permeability, when the oily wastewater is discharged through the oil discharge pipe 104, the force exerted on the filter screen 1 402 and the raised filter screen 405 by the water flow will also increase, causing the filter screen 1 402 to gradually move up. When the filter screen 1 402 moves up, the piston rod 407 moves up inside the sealing chamber 2 422. When the piston rod 407 moves up to be close to the magnetic block 411 at the top of the sealing chamber 2 422, the magnetic block 411 attracts the piston rod 407 under the action of the magnetic force. 07 moves up, pushing the shielding cylinder 408 upward, so that the shielding cylinder 408 moves up, and at the same time, the filter screen 1 402 and the filter screen 2 403 move up, and the magnetic block 2 406 contacts and attracts the magnetic block 3 410. At this time, the connecting groove 423 corresponds to the position of the blade group 420. At this time, as the rotating ring 3 401 rotates, the water flows through the connecting groove 423 to act on the blade group 420, driving the blade group 420 to rotate, and the rotation of the blade group 420 drives the convex shaft 419 to rotate. Further, by cyclically pushing the piston block 2 418, the liquid inside the processing tank 100 can be continuously pumped into the sealing chamber 1 421, pushing the piston block 1 416 downward, and the spring 2 417 is compressed. When the piston block 1 416 moves down to contact the slider 3 413 and pushes the slider 3 41 When the slider 3 moves downward, since the magnet at the top of the slider 3 413 is in contact and attracted with the magnetic block 5 415 at the top of the sealed chamber 1 421 in the initial state, and the liquid supply pipe 414 is blocked, when the slider 3 413 moves downward for a short distance, the slider 3 413 is out of contact with the magnetic block 5 415 above, the magnetic force decreases as the distance increases, and the magnetic force increases as the distance between the slider 3 413 and the magnetic block 5 415 below decreases, so that the slider 3 413 is out of contact with the magnetic block 5 415 above and then moves downward quickly to attract the magnetic block 5 415 below, exposing the liquid supply pipe 414. At this time, under the elastic reset action of the spring 2 417, the piston block 1 416 moves upward, and the liquid in the sealed chamber 1 421 is pumped into the sealed chamber 2 422 through the liquid supply pipe 414, pushing the piston Rod 407 moves downward, further driving filter screen 1 402 and filter screen 2 403 to move downward and reset. During the process of filter screen 1 402 moving downward and resetting, due to the attraction of magnetic block 2 406 and magnetic block 3 410, filter screen 2 403 begins to remain motionless, filter screen 1 402 moves downward, spring 1 404 is stretched, and at this time, through the relative movement of filter screen 1 402 and filter screen 2 403, filter screen 1 402 can produce relative movement with raised filter screen 405, and the spiral grooves matching filter screen 1 402 and raised filter screen 405 are used to scrape and clean the side wall of raised filter screen 405, scrape off the oil and impurities attached to the side wall of raised filter screen 405, restore the fluidity of raised filter screen 405, and realize the self-cleaning effect of raised filter screen 405. When filter screen 1 402 continues to move downward,After the spring 1 404 is stretched to the limit, it can drive the magnet 2 406 to break away from the magnet 3 410 and reset, so that the filter 2 403 moves down and recovers to be close to the filter 1 402, and the filter 1 402 and the filter 2 403 are reset, so that when the raised filter 405 is congested and the flowability becomes low, the device can drive the filter 1 402 to move up through the change of flowability and the change of buoyancy and force, and reset the filter 1 402 through the accumulation and release of the spring 2 417, and automatically clean the side wall of the raised filter 405 through the filter 1 402 during the reset process, so as to achieve the self-cleaning effect, effectively ensure the efficiency and stability of further filtering and impurity separation of the oil after the initial separation, and improve the efficiency of the device in removing oil and impurities.

[0044] It should be noted that when the piston rod 407 moves upward to push the shielding cylinder 408, it also pushes the slider 2 409. The slider 2 409 and the slider 3 413 only need to be pushed a short distance to automatically complete the subsequent displacement stroke through the cooperation with the magnetic block 411 to achieve displacement amplification. During the downward movement and resetting process of the piston rod 407, the shielding cylinder 408 is reset under the elastic force of the spring 3 424. After the piston rod 407 moves downward and pushes the slider 2 409 downward, the pressure relief port 412 is exposed. When 407 moves upward subsequently, the moisture in the sealing chamber 2 422 can be discharged unimpeded through the pressure relief port 412. When the piston rod 407 moves upward to push the slider 2 409, the pressure relief port 412 can be blocked to prevent the loss of water pressure entering through the liquid supply pipe 414. When the piston block 1 416 is reset under the action of the upward movement of the spring 2 417, the slider 3 413 can be pushed upward to drive the slider 3 413 to move upward, thereby blocking the liquid supply pipe 414 and ensuring the next working cycle of the device.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for removing oil and impurities from oilfield reinjection water, characterized in that: The treatment process adopts a treatment device comprising a treatment tank (100), wherein a drainage pipe (102) is arranged on the side wall of the treatment tank (100), an oil drainage pipe (104) is arranged on the top of the treatment tank (100), and a mud drainage pipe (103) is arranged on the bottom of the treatment tank (100); a centrifugal tank (200) is arranged inside the treatment tank (100), a liquid supply box (204) is arranged on the side wall of the centrifugal tank (200), an oil drainage tank (400) is arranged on the top of the centrifugal tank (200), and the oil drainage tank (400) is fixedly connected to the treatment tank (100); a sewage drainage tank (300) is arranged on the bottom of the centrifugal tank (200); a water inlet pipe (101) extending into the interior of the centrifugal tank (200) is arranged on the side wall of the treatment tank (100), and a cleaning mechanism is arranged inside the centrifugal tank (200), and the cleaning mechanism comprises a sealing ring (202) arranged on the side wall of the centrifugal tank (200). ), the sealing ring (202) is rotatably connected to a rotating ring (203) inside, the rotating ring (203) is provided with a driving blade (201), the driving blade (201) extends into the interior of the sewage tank (300) and the oil drain tank (400), and the driving blade (201) is in contact with the inner side walls of the centrifugal tank (200), the sewage tank (300) and the oil drain tank (400), and the side wall of the driving blade (201) is slidably connected to a slider (2 05), the slider one (205) is provided with a magnetic block six (213) which fits with the inner wall of the centrifugal tank (200), the outer wall of the centrifugal tank (200) is provided with a magnetic block one (206) which matches with the magnetic block six (213), the oil drain tank (400) is provided with a filtering mechanism for further removing impurities from the oil-water mixture entering the oil drain tank (400), and the swivel one (203) is provided with a liquid spraying mechanism for assisting the removal of impurities from the reinjected water; The treatment process comprises the following steps: S1: injecting reinjection water into the centrifugal tank (200) through the water inlet pipe (101), the reinjection water rotates inside the centrifugal tank (200), and under the action of centrifugal force, the light phase oil floats up and enters the oil drain tank (400), and the heavy phase impurities sink and enter the sewage tank (300); S2: After the light phase oil enters the oil drain tank (400), the centrifugal force increases, and the oil mixture is further separated and impurities are removed. The separated oil continues to float up and is sucked out through the oil drain pipe (104); S3: After the heavy phase mixture enters the sewage tank (300), it settles to the bottom of the treatment tank (100) under the action of centrifugal force and gravity and is discharged through the mud discharge pipe (103).

2. The oilfield reinjection water deoiling and impurity removal process according to claim 1, characterized in that: The inner diameters of the oil discharge tank (400), the centrifugal tank (200) and the sewage discharge tank (300) decrease in sequence; the inner side wall of the sewage discharge tank (300) is rotatably connected to a second rotating ring (302); the second rotating ring (302) is connected to a driving blade (201); and a stirring blade (301) coaxial with the second rotating ring (302) is provided at the bottom of the second rotating ring (302).

3. The oil field reinjection water deoiling and impurity removal process according to claim 1, characterized in that: The top of the sliding block 1 (205) is provided with an oblique angle facing the driving blade (201).

4. The oilfield reinjection water deoiling and impurity removal process according to claim 1, characterized in that: The magnetic block 1 (206) is in the form of a single closed loop on the outer wall of the centrifuge tank (200). Starting from the lowest point, the magnetic block 1 (206) gradually rises one grid at a time to reach the highest point, and then descends from the highest point to the lowest point in a grid-by-grid manner, forming a distribution pattern with a single undulation and connected end to end.

5. The oilfield reinjection water deoiling and impurity removal process according to claim 1, characterized in that: The liquid spraying mechanism comprises a slider block (208) slidably connected to the interior of the rotating ring (203); a liquid supply box (204) is arranged on the outer wall of the centrifugal tank (200); a flocculant is arranged inside the liquid supply box (204); a medicine tube (207) is connected to the bottom of the liquid supply box (204); a spring is arranged between the slider block (208) and the interior of the rotating ring (203); a piston protrusion (209) is arranged on the outer wall of the rotating ring (203) and is in contact with the inner wall of the rotating ring (203); and a liquid inlet (210) is arranged at the bottom of the rotating ring (203). and a liquid discharge port (211), the liquid inlet (210) being close to the slider four (208), the outlet of the medicine tube (207) extending to the interior of the rotating ring one (203) and close to the liquid inlet (210), and the medicine tube (207) and the liquid inlet (210) being located on the same side of the slider four (208), the liquid discharge port (211) being located on the other side of the slider four (208), and the inner side wall of the centrifuge tank (200) being provided with a nozzle (212) having a height and a number corresponding to the highest magnetic block one (206), and the nozzle (212) and the liquid discharge port (211) being in communication.

6. The oilfield reinjection water deoiling and impurity removal process according to claim 1, characterized in that: The filtering mechanism comprises a swivel three (401) rotatably connected to the oil drain tank (400), the swivel three (401) being connected to the driving blade (201), the swivel three (401) being provided with a sealing chamber one (421) and a sealing chamber two (422) inside, the sealing chamber two (422) being sleeved with a piston rod (407), the bottom of the piston rod (407) extending to the outside of the swivel three (401) and the piston rod (407) The bottom of the rotating ring (401) is connected to a filter screen 1 (402), the top of the filter screen 1 (402) is provided with a filter screen 2 (403), a spring 1 (404) is provided between the filter screen 1 (402) and the filter screen 2 (403), the top of the rotating ring (401) is rotatably connected to a blade group (420), the rotating shaft of the blade group (420) is also connected to a convex shaft (419), and the interior of the rotating ring (401) is provided with a spring corresponding to the convex shaft (419). The piston block 1 (418) is sleeved inside the sealing chamber 1 (421), a spring 2 (417) is arranged between the piston block 1 (416) and the sealing chamber 1 (421), a liquid supply pipe (414) is arranged between the sealing chamber 1 (421) and the sealing chamber 2 (422), a pressure relief port (412) is provided on the side wall of the sealing chamber 2 (422), and a pressure relief port (412) is sleeved inside the rotating ring 3 (401) and a pressure relief port (414) is provided on the side wall of the sealing chamber 2 (422). The third rotating ring (401) is provided with a slider three (413) corresponding to the tube (414), the interior of the third rotating ring (401) is sleeved with a slider two (409) corresponding to the pressure relief port (412), the interior of the third rotating ring (401) is sleeved with a shielding cylinder (408) corresponding to the blade group (420), the bottom of the third rotating ring (401) is provided with a magnetic block three (410), and the top of the second filter screen (403) is provided with a magnetic block two (406) corresponding to the magnetic block three (410).

7. The oilfield reinjection water deoiling and impurity removal process according to claim 6, characterized in that: Both ends of the slider three (413) and the slider two (409) are designed with magnets, the top and bottom of the inner cavity of the sealed cavity one (421) are provided with a magnetic block five (415) corresponding to the slider three (413), and the top and bottom of the inner cavity of the sealed cavity two (422) are provided with a magnetic block four (411) corresponding to the slider two (409), and a magnet is provided at the top of the piston rod (407), and the piston rod (407) is designed to cooperate with the magnetic block four (411).

8. The oilfield reinjection water deoiling and impurity removal process according to claim 6, characterized in that: The shielding cylinder (408) is provided with a connecting groove (423) matching the blade assembly (420), a spring three (424) is provided between the inner side of the shielding cylinder (408) and the rotating ring three (401), and a push rod extending into the interior of the sealing chamber two (422) is provided at the bottom of the shielding cylinder (408).

9. The oilfield reinjection water deoiling and impurity removal process according to claim 6, characterized in that: A raised filter screen (405) is provided in the middle of the filter screen 2 (403), and the raised filter screen (405) is of spiral design. A notch matching the raised filter screen (405) is provided on the surface of the filter screen 1 (402), and the filter screens 1 (402) and 2 (402) are connected via the notch.

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