Carbon dioxide flooding well corrosion inhibitor filling device

Abstract

The embodiment of the invention provides a carbon dioxide flooding well corrosion inhibitor filling device, and relates to the field of oil exploitation. Comprising a frame, a mixing mechanism, a water return device and a cleaning mechanism, the material mixing mechanism is mounted in the frame; the water return device is mounted on the side wall of the frame; the cleaning mechanism is connected with the water return device; the water return device comprises a water tank, a water return pump, a feeding pipe and an extraction pipe; the water tank is installed on the side wall of the frame and is of a hollow structure with the top open. The water return pump is mounted on the cleaning mechanism; and one end of the feeding pipe is mounted at the output end of the water return pump. The corrosion inhibitor and water can be mixed, a corrosion inhibitor solution can be rapidly formed, meanwhile, the corrosion inhibitor solution in an oil well can be sucked out, filtering is carried out, impurities in the backflow solution are scraped and collected, and follow-up cleaning is facilitated; and the solution output proportion can be automatically adjusted according to the solution amount change, so that stable supply of the oil well corrosion inhibitor solution is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of oil extraction, and specifically refers to an inhibitor injection device for carbon dioxide flooding wells. Background Art

[0002] With the vigorous development of the global economy, the demand for oil resources continues to climb and remains at a high level. Against this background, a series of enhanced oil recovery technologies have emerged one after another to effectively improve the crude oil recovery rate. Among them, carbon dioxide flooding, as a highly potential technology, involves precisely injecting carbon dioxide gas into the reservoir. By virtue of the complex physical and chemical interactions between carbon dioxide and crude oil, it aims to reduce the viscosity of crude oil, cause the volume of crude oil to expand, and enhance the fluidity of crude oil, thereby significantly increasing the crude oil recovery rate.

[0003] However, during the process of carbon dioxide flooding, the problem of equipment corrosion has become a major obstacle. In view of this, the application of inhibitors has become an effective way to solve this problem. Inhibitors are essentially a class of chemical substances that can adsorb and react on the metal surface to form a dense protective film, which can effectively prevent or significantly slow down the corrosion process of the metal. In the operation scenario of carbon dioxide flooding wells, injecting inhibitors into the well can significantly reduce the corrosion rate of carbon dioxide on oil well equipment such as pipes, valves, and pumps, effectively ensuring the extension of the service life of the equipment and ensuring the safe, stable, and continuous production of the oil well.

[0004] At the current stage, the structural design of the existing inhibitor injection devices is generally relatively simple. Usually, a metering pump is used to inject the inhibitor in the chemical agent tank into the pipeline connected to the wellhead. To optimize the effectiveness of the inhibitor, some devices adopt a continuous injection / reflux circulation mode, that is, on the one hand, continuously inject the inhibitor solution into the well, and on the other hand, use the return pipe to extract the inhibitor solution in the well to form a circulation system of the inhibitor solution.

[0005] However, such existing devices have obvious defects. When extracting the reflux inhibitor solution, due to the complex oil well environment, the solution often contains impurities such as sediment and crude oil particles. These impurities flow back with the solution, and the existing devices at the current stage fail to effectively filter and clean this part of the inhibitor solution mixed with impurities, making it difficult to achieve reuse. This not only causes serious waste of the inhibitor but also may affect the normal operation of the device due to the accumulation of impurities.

[0006] Based on this, the present invention is proposed. Summary of the Invention

[0007] According to an embodiment of the present invention, an inhibitor injection device for carbon dioxide flooding wells is provided. It is used to solve the problems in the existing background.

[0008] In a first aspect of the present invention, a corrosion inhibitor injection device for a carbon dioxide enhanced oil recovery well is provided.

[0009] The corrosion inhibitor injection device for the carbon dioxide enhanced oil recovery well includes: a frame, a mixing mechanism, a water return device, and a cleaning mechanism; The mixing mechanism is installed inside the frame; the water return device is installed on the side wall of the frame; the cleaning mechanism is connected to the water return device; The water return device includes: a water tank, a water return pump, a delivery pipe, and a suction pipe; the water tank is installed on the side wall of the frame, and the water tank is a hollow structure with an open top; the water return pump is installed on the cleaning mechanism; one end of the delivery pipe is installed at the output end of the water return pump, and the other end of the delivery pipe corresponds to the water tank; the suction pipe is installed at the suction end of the water return pump; The mixing mechanism includes: a mixing tank and a water outlet pipe; the mixing tank is installed inside the frame, and the water outlet pipe is installed on the mixing tank; A flow control mechanism is installed between the mixing mechanism and the water return device, and the flow control mechanism can control the output ratio of the fluids in the mixing mechanism and the water return device.

[0010] Preferably, it includes: a first bracket, a second bracket, a hopper, and a water storage tank; Both the first bracket and the second bracket are installed on the frame; the hopper is installed on the second bracket, and the water storage tank is installed on the first bracket; the hopper and the water storage tank are respectively connected to the top of the mixing tank through connecting pipes.

[0011] Preferably, the water return device further includes: a mesh plate, a baffle, and an overflow trough; The mesh plate is installed on the top of the water tank, and a plurality of mesh holes are arranged in an array on the mesh plate; the baffle is installed on the water tank, and an overflow trough is formed between the baffle and the outer wall of the water tank.

[0012] Preferably, the cleaning mechanism includes: a fixing plate, a mounting frame, a reciprocating lead screw, a first motor, a sliding block, a slider, a moving frame, a chute, a scraper, a driving rod, and a blind groove; There are two fixing plates, which are symmetrically installed at the top of the water tank; the mounting frames are symmetrically installed at the top of the water tank, and the straight line passing through the centers of the two fixing plates and the straight line passing through the centers of the two mounting frames are perpendicular to each other; both ends of the reciprocating lead screw are rotatably installed on the two mounting frames; the first motor is installed on one of the mounting frames, and one end of the reciprocating lead screw is connected to the output end of the first motor; the sliding block is installed on the reciprocating lead screw; the slider is fixedly connected to the sliding block; the chute is opened in the moving frame, and the slider is slidably installed in the chute; the scraping plate is installed on the lower surface of the moving frame; there are two driving rods, which are symmetrically installed on both sides of the moving frame; there are two blind slots, which are symmetrically opened on the opposite sides of the two fixing plates respectively, and the two driving rods are slidably installed in the two blind slots respectively.

[0013] Preferably, a limiting rod is also installed between the two mounting frames, and the limiting rod passes through the sliding block.

[0014] Preferably, the blind slot includes: a translation section, a first transition section, a second transition section, a return section, a third transition section and a flexible baffle; The translation section, the first transition section, the second transition section, the return section and the third transition section are connected in sequence; The flexible baffle is obliquely installed between the first transition section and the second transition section.

[0015] Preferably, the mixing mechanism further includes: a stirring paddle, a housing, a first gear, a second gear, a toothed belt and a second motor; The mixing tank is installed in the frame, and the hopper and the water storage tank are respectively connected to the top of the mixing tank through connecting pipes; there are two stirring paddles, which are respectively rotatably installed in the mixing tank; the housing is installed on the mixing tank; the first gear and the second gear are respectively rotatably installed in the housing, and the first gear and the second gear are respectively connected to the two stirring paddles; the toothed belt is installed between the first gear and the second gear; the second motor is installed on the housing, and the output end of the second motor is connected to the first gear; the water outlet pipe is installed on the mixing tank.

[0016] Preferably, the mixing mechanism further includes: a limiting wheel, and there are several limiting wheels, which are respectively rotatably installed in the housing and are in rolling contact with the toothed belt.

[0017] Preferably, the diameter of the first gear is smaller than the diameter of the second gear.

[0018] Preferably, a flow control mechanism is installed between the water outlet pipe and the water tank, and the flow control mechanism can control the output ratio of the fluid in the mixing tank and the water tank.

[0019] Preferably, the flow control mechanism includes: a flow control box, a first inlet, an outlet, an output pump, a side box body, a floating cylinder, an extension rod, a cross bar, a turntable, a swing rod, a compensation groove, a valve plate, a through hole, a branch pipe and a second inlet; One end of the water outlet pipe far away from the mixing tank extends into the flow control box; the end of the water outlet pipe extending into the flow control box is the first inlet; the outlet is installed on the flow control box; the output pump is installed in the frame, and the suction end of the output pump is connected to the outlet; the side box body is installed on the side wall of the water tank, and the side box body is communicated with the inner cavity of the water tank; the floating cylinder is slidably installed in the side box body; the extension rod is installed at the top of the floating cylinder, and the extension rod slidably extends out of the top of the side box body; the cross bar is hinged to the extension rod; the turntable is rotatably installed on the flow control box; the swing rod is installed on the turntable; the compensation groove is opened on the swing rod, and the cross bar is slidably installed in the compensation groove; the valve plate is rotatably installed in the flow control box, and the valve plate is connected to the turntable; there are two through holes, which are respectively opened on the valve plate; one end of the branch pipe is connected to the water tank, and the other end of the branch pipe extends into the flow control box; the end of the branch pipe extending into the flow control box is the second inlet; The valve plate fits with the first inlet and the second inlet.

[0020] One or more technical solutions provided in the present application have at least the following technical effects or advantages: 1. A corrosion inhibitor injection device for a carbon dioxide flooding well provided by the present invention can realize the mixing of the corrosion inhibitor and water through the mixing mechanism, ensure that the corrosion inhibitor solution can be quickly formed, and at the same time, through the differential rotation of the two stirring paddles, the mixing can be accelerated.

[0021] 2. The water return pump in the present invention sucks out the corrosion inhibitor solution in the oil well and filters it by using the mesh plate. At the same time, the cleaning mechanism can scrape off the sundries mixed in the returned corrosion inhibitor solution and collect the sundries centrally for easy cleaning.

[0022] 3. The flow control mechanism in the present invention can automatically adjust the output ratio of the solution in the mixing tank and the water tank according to the change of the solution volume in the water tank, ensure that when the amount of the corrosion inhibitor solution in the oil well is sufficient, the corrosion inhibitor solution in the water tank participates in all cycles, and when the solution volume in the water tank decreases, the solution in the mixing tank can be automatically supplemented to ensure the stable supply of the corrosion inhibitor solution in the oil well.

[0023] In summary, the present invention can mix the corrosion inhibitor with water to quickly form a corrosion inhibitor solution. At the same time, it can suck out the corrosion inhibitor solution in the oil well, filter it, and scrape and collect the sundries in the reflux solution, which is convenient for subsequent cleaning. It can also automatically adjust the solution output ratio according to the change in the solution volume to ensure the stable supply of the corrosion inhibitor solution for the oil well.

[0024] It should be understood that the content described in the Summary of the Invention section is not intended to limit the key or important features of the embodiments of the present invention, nor to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Combined with the accompanying drawings and referring to the following detailed description, the above and other features, advantages, and aspects of the embodiments of the present invention will become more obvious. In the drawings, the same or similar reference numerals represent the same or similar elements, where: Figure 1 shows a schematic structural diagram of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 2 shows an exploded structural diagram of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 3 shows a schematic cross-sectional structure diagram of the outer shell of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 4 shows a schematic cross-sectional structure diagram of a mixing tank of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 5 shows a schematic diagram of the separation state of the cleaning mechanism and the water tank of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 6 shows a schematic structure diagram of the water tank of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 7 shows an exploded structural diagram of the cleaning mechanism of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 8 shows a right view of the exploded structure of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 9 shows a schematic structural diagram of the flow control mechanism of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 10 shows a schematic diagram of the position of the float in the flow control mechanism of a corrosion inhibitor injection device for a carbon dioxide flooding oil well according to an embodiment of the present invention; Figure 11Shows a cross-sectional view of the flow control box of the corrosion inhibitor injection device for a carbon dioxide enhanced oil recovery well according to an embodiment of the present invention; Figure 12 Shows a schematic diagram of the rotational state of the valve plate of the corrosion inhibitor injection device for a carbon dioxide enhanced oil recovery well according to an embodiment of the present invention; Figure 13 Shows a front view of the blind groove of the corrosion inhibitor injection device for a carbon dioxide enhanced oil recovery well according to an embodiment of the present invention.

[0026] The reference numerals are as follows: 1, frame; 2, first bracket; 3, second bracket; 4, hopper; 5, water storage tank; 6, mixing mechanism; 61, mixing box; 62, stirring paddle; 63, outer shell; 64, first gear; 65, second gear; 66, toothed belt; 67, second motor; 68, water outlet pipe; 69, limiting wheel; 7, water tank; 701, mesh plate; 8, baffle; 801, overflow tank; 9, return water pump; 10, delivery pipe; 11, extraction pipe; 12, cleaning mechanism; 121, fixing plate; 122, mounting frame; 123, reciprocating lead screw; 124, first motor; 125, sliding block; 1251, limiting rod; 126, slider; 127, moving frame; 128, chute; 129, scraper; 1210, driving rod; 1211, blind groove; 12111, translation section; 12112, first transition section; 12113, second transition section; 12114, return section; 12115, third transition section; 12116, flexible baffle; 13, flow control mechanism; 131, flow control box; 132, first inlet; 133, outlet; 134, output pump; 135, side box body; 136, float; 137, extension rod; 138, cross bar; 139, turntable; 1310, swing rod; 1311, compensation groove; 1312, valve plate; 1313, through hole; 1314, branch pipe; 1315, second inlet. Detailed implementation manners

[0027] To make the objectives, 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 with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] In addition, the term "and / or" in this article is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after. Example 1:

[0029] As Figure 1 and Figure 2 shown, this corrosion inhibitor injection device for carbon dioxide enhanced oil recovery wells includes: a frame 1, a first support 2, a second support 3, a hopper 4, a water storage tank 5, a mixing mechanism 6, a water return device, and a cleaning mechanism 12. The first support 2 and the second support 3 are both installed on the frame 1. The hopper 4 is installed on the second support 3, and the water storage tank 5 is installed on the first support 2. The mixing mechanism 6 is installed inside the frame 1, and the hopper 4 and the water storage tank 5 are respectively connected to the mixing mechanism 6.

[0030] As Figure 2 , Figure 3 and Figure 4 shown, the mixing mechanism 6 includes: a mixing box 61, stirring paddles 62, a housing 63, a first gear 64, a second gear 65, a toothed belt 66, a second motor 67, a water outlet pipe 68, and a limiting wheel 69. The mixing box 61 is installed inside the frame 1, and the mixing box 61 is a hollow box structure. The hopper 4 and the water storage tank 5 are respectively connected to the top of the mixing box 61 through connecting pipes, and electric valves are respectively installed on the connecting pipes connecting the hopper 4 and the water storage tank 5 to the mixing box 61. The electric valves are existing equipment and adopt electromagnetic control technology, which can open the corresponding passages according to requirements, so as to control the feeding of the materials in the hopper 4 and the water storage tank 5 into the mixing box 61, and the corrosion inhibitor is contained in the hopper 4. There are two stirring paddles 62, which are respectively rotatably installed inside the mixing box 61. During the rotation process of the stirring paddles 62, the materials and water can be fully tumbled and mixed inside the mixing box 61, improving the mixing efficiency and uniformity. The housing 63 is installed on the mixing box 61, playing a role in protecting the internal transmission components. The first gear 64 and the second gear 65 are respectively rotatably installed inside the housing 63, and the first gear 64 and the second gear 65 are respectively connected to the two stirring paddles 62. The toothed belt 66 is installed between the first gear 64 and the second gear 65, and the toothed belt 66 is meshed with the first gear 64 and the second gear 65, so as to realize the synchronous rotation of the two gears. The diameter of the first gear 64 is smaller than that of the second gear 65, ensuring that the rotation time of the first gear 64 for one circle is different from that of the second gear 65 for one circle, so that the rotation speeds of the two stirring paddles 62 are different. By using the differential rotation of the two stirring paddles 62, the chaos degree of the materials in the mixing box 61 during stirring is increased, and the mixing effect is better. In addition, there are several limiting wheels 69, which are respectively rotatably installed inside the housing 63 and are in rolling contact with the toothed belt 66. By using the limiting function of the limiting wheels 69, the toothed belt 66 can be accurately meshed with the first gear 64 and the second gear 65, avoiding tooth skipping. The second motor 67 is installed on the housing 63, and the output end of the second motor 67 is connected to the first gear 64. Starting the second motor 67 can drive the first gear 64 to rotate. The water outlet pipe 68 is installed on the mixing box 61 and is located at the bottom, for discharging the mixed solution in the mixing box 61.

[0031] The water return device is installed on the side wall of the frame 1, and its core function is to pump the corrosion inhibitor solution in the oil well back into the device. During actual operation, it closely cooperates with the mixing mechanism 6 that continuously outputs the corrosion inhibitor solution, and the two work together to build a circulation system for the corrosion inhibitor solution. As the oil well operation continues, various impurities in the oil well will gradually mix into the corrosion inhibitor solution. And this water return device ensures the stable effect of the corrosion inhibitor solution in the oil well by accurately pumping the used corrosion inhibitor solution in the oil well and cooperating with the newly input clean corrosion inhibitor solution. The cleaning mechanism 12 is connected to the water return device, and the cleaning mechanism 12 is used to clean the impurities in the pumped-back corrosion inhibitor solution. Refer to Figure 2 、 Figure 5 and Figure 6As shown in the figure, the water return device includes: a water tank 7, a mesh plate 701, a baffle 8, an overflow tank 801, a water return pump 9, a delivery pipe 10, and a suction pipe 11. The water tank 7 is installed on the side wall of the frame 1. The water tank 7 is a hollow structure with an open top and can hold the back-pumped corrosion inhibitor solution. The mesh plate 701 is installed on the top of the water tank 7 and is installed by being embedded in a card slot, which is convenient for disassembly, cleaning, and maintenance. A number of mesh holes are arranged in an array on the mesh plate 701, which can effectively intercept sediment, particulate impurities, etc. in the back-pumped solution and does not affect the passage of the corrosion inhibitor solution. The baffle 8 is installed on the water tank 7, and an overflow tank 801 is formed between the baffle 8 and the outer wall of the water tank 7. The baffle 8 and the outer wall of the water tank 7 are fixedly connected by sealant to form the overflow tank 801. The use of sealant ensures the connection tightness between the baffle 8 and the water tank 7 and prevents water leakage. The overflow tank 801 is used to collect the blocked sediment. At the same time, if the flow rate of the back-pumped corrosion inhibitor solution is greater than the flow rate of the corrosion inhibitor solution passing through the mesh plate 701, the excess liquid can flow into the overflow tank 801 for collection. In addition, a cleaning pipe communicating with the outside can be added to the overflow tank 801. With the cooperation of the valve, it is convenient for cleaning. Such a design avoids water overflow from polluting the surrounding environment and at the same time maintains the stable operation of the entire water return system. In addition, the bottom of the overflow tank 801 is designed with a certain slope to facilitate the directional concentration of sludge and facilitate cleaning. At the same time, a circulating water pipe is provided on the water tank 7. By using this circulating water pipe, the filtered corrosion inhibitor can be returned to the oil well, thereby realizing the circulation of the corrosion inhibitor solution. The water return pump 9 is installed on the cleaning mechanism 12. One end of the delivery pipe 10 is installed at the output end of the water return pump 9, and the other end of the delivery pipe 10 is located at the top of the mesh plate 701 and corresponds to the mesh plate 701. The suction pipe 11 is installed at the suction end of the water return pump 9. During use, first put the solution in the mixing tank 61 into the oil well, and at the same time put the suction pipe 11 into the oil well. Turn on the water return pump 9 to pump out the corrosion inhibitor solution in the oil well and put it at the top of the mesh plate 701. The corrosion inhibitor solution enters the water tank 7 for collection, while the sundries are blocked at the top of the mesh plate 701. When the amount of solution entering and leaving the water tank 7 is sufficient, close the solution output of the mixing tank 61, and rely on the solution in the water tank 7 to complete the circulation of the corrosion inhibitor solution, and a dynamic balance state of the solution can be achieved.

[0032] Reference Figure 2 、 Figure 5 、 Figure 7 and Figure 13As shown in the figure, the cleaning mechanism 12 includes: a fixing plate 121, a mounting frame 122, a reciprocating lead screw 123, a first motor 124, a sliding block 125, a limiting rod 1251, a slider 126, a moving frame 127, a chute 128, a scraper 129, a driving rod 1210, and a blind slot 1211. There are two fixing plates 121, which are symmetrically mounted on the top of the water tank 7. The mounting frames 122 are symmetrically mounted on the top of the water tank 7, and the straight line passing through the centers of the two fixing plates 121 and the straight line passing through the centers of the two mounting frames 122 are perpendicular to each other. The two ends of the reciprocating lead screw 123 are respectively rotatably mounted on the two mounting frames 122. The first motor 124 is mounted on one of the mounting frames 122, and one end of the reciprocating lead screw 123 is connected to the output end of the first motor 124. Turning on the first motor 124 can drive the reciprocating lead screw 123 to rotate. The sliding block 125 is mounted on the reciprocating lead screw 123. A slider adapted to the reciprocating lead screw 123 is installed in the sliding block 125, and this slider is embedded in the thread of the reciprocating lead screw 123. When the reciprocating lead screw 123 rotates, the sliding block 125 can reciprocate along the axial direction of the reciprocating lead screw 123. A limiting rod 1251 is also mounted between the two mounting frames 122, and the limiting rod 1251 passes through the sliding block 125. By the limitation of the limiting rod 1251, the sliding block 125 can be ensured to slide stably and prevent the sliding block 125 from rotating. The slider 126 is fixedly connected to the sliding block 125. The chute 128 is opened in the moving frame 127, and the slider 126 is slidably mounted in the chute 128. Both the chute 128 and the slider 126 are arranged in the up and down direction, and their sliding cooperation enables the moving frame 127 to move only in the up and down direction. The scraper 129 is mounted on the lower surface of the moving frame 127, and the scraper 129 is used to scrape off the sundries accumulated on the top of the mesh plate 701. There are two driving rods 1210, which are symmetrically mounted on both sides of the moving frame 127. There are two blind slots 1211, which are respectively symmetrically opened on the opposite sides of the two fixing plates 121. The two driving rods 1210 are respectively slidably mounted in the two blind slots 1211. When the sliding block 125 moves along the axial direction of the reciprocating lead screw 123, the driving rod 1210 can slide in the blind slot 1211. When the sliding block 125 returns, by the cooperation of the blind slot 1211 and the driving rod 1210, the scraper 129 is separated from the top of the mesh plate 701 to prevent sundries from accumulating in the corner on the side far from the overflow tank 801. The blind slot 1211 includes: a translation section 12111, a first transition section 12112, a second transition section 12113, a return section 12114, a third transition section 12115, and a flexible baffle 12116. The translation section 12111, the first transition section 12112, the second transition section 12113, the return section 12114, and the third transition section 12115 are connected in sequence. Among them, the length of the translation section 12111 is greater than the length of the water tank 7 along the axial direction of the reciprocating lead screw 123.The flexible baffle 12116 is inclined and installed between the first transition section 12112 and the second transition section 12113, and the flexible baffle 12116 is used for guiding.

[0033] The specific usage method of the above structure is as follows: When the first motor 124 starts, the reciprocating lead screw 123 rotates. Restricted by the limiting rod 1251, the sliding block 125 will perform a linear reciprocating motion along the reciprocating lead screw 123. With the movement of the sliding block 125, by using the cooperation of the slider 126 and the chute 128, the moving frame 127 and the scraper 129 can move together. By scraping the upper surface of the mesh plate 701 with the scraper 129, the sludge is pushed into the overflow tank 801. During this process, the driving rod 1210 slides in the translation section 12111 of the blind slot 1211, and during this process, the scraper 129 always adheres to the mesh plate 701. When the driving rod 1210 moves to a position near the first transition section 12112 in the translation section 12111, the scraper 129 leaves the mesh plate 701. When the sliding block 125 moves to the thread end at one end of the reciprocating lead screw 123, the driving rod 1210 moves through the first transition section 12112 into the second transition section 12113, and at the same time, it squeezes and then disengages from the flexible baffle 12116 during this process, so as to prevent the driving rod 1210 from resetting in the reverse direction by using the limit of the flexible baffle 12116. The reciprocating lead screw 123 continues to rotate, and the sliding block 125 starts to move along the return section 12114. At the same time, the scraper 129 is lifted during this process to avoid the reverse pushing of sludge and sundries until the sliding block 125 moves to the thread end at the other end of the reciprocating lead screw 123, and then the driving rod 1210 corresponds to the translation section 12111 again. Subsequently, the sliding block 125 moves back towards the first transition section 12112, and at the same time, with the self-weight of the moving frame 127, it is ensured that the driving rod 1210 can accurately enter the translation section 12111. In this way, the sundries in the continuously pushed and scraped and recycled corrosion inhibitor can be continuously removed.

[0034] By using the above structure, the rotation of the reciprocating lead screw 123 can be utilized to make the sliding block 125 reciprocate, and in cooperation with the scraper 129, the sludge on the surface of the mesh plate 701 can be continuously scraped off. In addition, through the limitation of the driving rod 1210 by each part of the blind slot 1211, the moving frame 127 can drive the scraper 129 to move up and down, ensuring that the forward movement of the scraper 129 can scrape off sundries, while avoiding pushing the sludge back to the corner during the return journey. Embodiment 2:

[0035] During the actual operation of a carbon dioxide flooding well, the corrosion inhibitor solution injected into the well will gradually be consumed as it continues to be used. When the liquid level of the corrosion inhibitor solution in the well drops to a level where it cannot fully cover the working section, its protective effect on the well equipment will be greatly reduced. However, due to the fact that the depth of the well can easily reach several hundred meters or even deeper, the downhole environment is complex and the light is dim, making it difficult for workers to directly observe the specific inventory of the corrosion inhibitor solution in the well. Therefore, it is difficult to control the timing of manually adding the corrosion inhibitor solution. In view of this, the solution of this embodiment is proposed.

[0036] The difference between this embodiment and Embodiment 1 is that a flow control mechanism 13 is installed between the water outlet pipe 68 and the water tank 7. The flow control mechanism 13 can control the output ratio of the fluid in the mixing tank 61 and the water tank 7. When the amount of the corrosion inhibitor solution in the well is sufficient, the inventory of the corrosion inhibitor solution in the water tank 7 is sufficient for the circulation of the corrosion inhibitor solution in the well, and the solution in the mixing tank 61 will not be replenished. When the amount of the solution in the water tank 7 drops, the solution in the mixing tank 61 can be automatically replenished, and at the same time, the output flow of the water tank 7 is reduced until the amount of the corrosion inhibitor solution participating in the circulation returns to the sufficient state.

[0037] Reference Figure 8 、 Figure 9 、 Figure 10 、 Figure 11 and Figure 12As shown in the figure, the flow control mechanism 13 includes: a flow control box 131, a first inlet 132, an outlet 133, an output pump 134, a side box 135, a floating cylinder 136, an extension rod 137, a cross bar 138, a turntable 139, a swing rod 1310, a compensation groove 1311, a valve plate 1312, a through hole 1313, a branch pipe 1314, and a second inlet 1315. One end of the water outlet pipe 68 far from the mixing box 61 extends into the flow control box 131. The end of the water outlet pipe 68 extending into the flow control box 131 is the first inlet 132. The water outlet pipe 68 serves as a channel for discharging the mixed corrosion inhibitor solution from the mixing box 61, enabling the solution in the mixing box 61 to be input into the flow control box 131. The outlet 133 is installed on the flow control box 131. The output pump 134 is installed in the frame 1, and the suction end of the output pump 134 is connected to the outlet 133. The output pump 134 serves as the power core for pushing the fluid to be transported outward, capable of sucking out the solution in the flow control box 131. The output end of the output pump 134 is connected with a pipe, and this pipe is used to introduce the corrosion inhibitor solution into the oil well. The side box 135 is installed on the side wall of the water tank 7, and the side box 135 is communicated with the inner cavity of the water tank 7, forming an integral liquid storage space. The floating cylinder 136 is slidably installed in the side box 135. The floating cylinder 136 is made of lightweight and corrosion-resistant polyethylene material into a hollow cylinder structure. The overall density is less than that of the corrosion inhibitor solution, and it can float on the liquid surface of the corrosion inhibitor solution. Its outer diameter is smaller than the inner diameter of the side box 135, ensuring that it can freely slide in the vertical direction in the side box 135 and maintaining a gap with the box wall to ensure that it will not get stuck. The extension rod 137 is installed at the top of the floating cylinder 136, and the extension rod 137 slides and extends out of the top of the side box 135. The cross bar 138 is hinged to the extension rod 137. The turntable 139 is rotatably installed on the flow control box 131. The swing rod 1310 is installed on the turntable 139. The compensation groove 1311 is opened on the swing rod 1310, and the cross bar 138 is slidably installed in the compensation groove 1311. When the floating cylinder 136 moves up and down, it can utilize the cooperation of the cross bar 138 and the compensation groove 1311 to make the swing rod 1310 and the turntable 139 rotate. At the same time, the cross bar 138 slides in the compensation groove 1311 to avoid interference. One end of the branch pipe 1314 is connected to the water tank 7, and the other end of the branch pipe 1314 extends into the flow control box 131. The branch pipe 1314 can enable the solution in the water tank 7 to be input into the flow control box 131. The end of the branch pipe 1314 extending into the flow control box 131 is the second inlet 1315. The valve plate 1312 is rotatably installed in the flow control box 131, and the valve plate 1312 is connected to the turntable 139. There are two through holes 1313, which are respectively opened on the valve plate 1312. The valve plate 1312 is in contact with the first inlet 132 and the second inlet 1315. The valve plate 1312 is used to close the first inlet 132 and the second inlet 1315. When the valve plate 1312 rotates, it can enable the two through holes 1313, thereby respectively opening the first inlet 132 and the second inlet 1315.

[0038] The actual working principle of the above structure is as follows: In the initial stage, there is no liquid in the water tank 7, and the buoy 136 is located at the lowest position of the side box 135 due to its own gravity. At this time, the valve plate 1312 completely blocks the second inlet 1315, and one of the through holes 1313 on the valve plate 1312 just corresponds to the first inlet 132. The solution in the mixing tank 61 will pass through the water outlet pipe 68 and the first inlet 132, and smoothly enter the flow control tank 131 through this through hole 1313. After the output pump 134 is turned on, the solution is sent into the oil well through the outlet 133. Subsequently, the return water pump 9 is turned on, and the solution in the oil well is sucked into the water tank 7. As the liquid level in the water tank 7 continuously rises, the liquid level in the side box 135 communicated with the inner cavity of the water tank 7 also rises synchronously, and the buoy 136 rises accordingly under the action of buoyancy. When the buoy 136 rises, the extension rod 137 installed at its top drives the cross bar 138 to rise. The cross bar 138 slides in the compensation groove 1311 of the swing rod 1310, and the cooperation between the two causes the swing rod 1310 to swing, thereby driving the connected turntable 139 to rotate. Since the valve plate 1312 is connected to the turntable 139, the rotation of the turntable 139 causes the valve plate 1312 to rotate accordingly, and the two through holes 1313 on the valve plate 1312 also rotate. When the valve plate 1312 rotates, the through hole 1313 originally corresponding to the first inlet 132 is gradually misaligned, so that the solution flow rate entering the flow control tank 131 from the mixing tank 61 gradually decreases; at the same time, the other through hole 1313 gradually corresponds to the second inlet 1315, and the reflux solution in the water tank 7 passes through the branch pipe 1314 and the second inlet 1315, and participates in the cycle through this through hole 1313. And as the valve plate 1312 continues to rotate, the amount of solution in the water tank 7 participating in the cycle gradually increases, and the output amount of the solution in the mixing tank 61 gradually decreases. When the liquid level in the water tank 7 rises to a sufficiently high position, the buoy 136 rises to the highest position of the side box 135. At this time, the valve plate 1312 rotates to a specific position and completely blocks the first inlet 132, and the solution in the mixing tank 61 stops outputting, and all the solution participating in the cycle comes from the water tank 7. When the amount of solution decreases, that is, the liquid level in the water tank 7 drops, the buoy 136 drops accordingly under the action of gravity. Similarly, using the cooperation between the cross bar 138 and the compensation groove 1311, the swing rod 1310 drives the turntable 139 to rotate in the reverse direction, and then the valve plate 1312 rotates in the reverse direction. During the reverse rotation of the valve plate 1312, the through hole 1313 originally corresponding to the second inlet 1315 is gradually misaligned, and the amount of solution in the water tank 7 participating in the cycle decreases; while the other through hole 1313 gradually corresponds to the first inlet 132, and the new solution in the mixing tank 61 is replenished into the cycle to maintain the stability of the circulating solution amount. Through the above process, the flow control mechanism 13 can automatically adjust the output ratio of the solution in the mixing tank 61 and the water tank 7 according to the change of the solution amount in the water tank 7, and ensure the stable supply of the corrosion inhibitor solution in the oil well.

[0039] In actual use, the end of the extraction pipe 11 in the well is higher than the end of the pipe for injecting the corrosion inhibitor into the well, which is connected to the output pump 134. The end of the pipe connected to the output pump 134 extends to the bottom of the oil well, and the height difference between it and the end of the extraction pipe 11 is the coverage depth of the corrosion inhibitor in the oil well, and this depth is not less than the thickness of the downhole operation layer. Therefore, it can be understood that only when the corrosion inhibitor in the well gradually accumulates to cover the end of the extraction pipe 11 in the well, the return water pump 9 will suck the corrosion inhibitor in the well into the water tank 7. Based on this, in the initial state, the return water pump 9 is pre-opened. At this time, the floating cylinder 136 is located at the bottom end of the side box 135, and all the corrosion inhibitor injected into the well comes from the mixing tank 61; when the corrosion inhibitor in the well accumulates to the end of the extraction pipe 11, the corrosion inhibitor in the well begins to flow back to the water tank 7. As the amount of the recovered corrosion inhibitor in the water tank 7 increases, the floating cylinder 136 begins to rise, thereby causing the valve plate 1312 to rotate, reducing the flow rate of the corrosion inhibitor injected into the well by the mixing tank 61, and at the same time injecting the corrosion inhibitor in the water tank 7 into the well. Until the liquid level in the water tank 7 reaches a certain height, the floating cylinder 136 rises to the highest position, and the valve plate 1312 rotates to completely close the input channel of the mixing tank 61. At this time, all the corrosion inhibitor in the well comes from the water tank 7 and circulates. As the corrosion inhibitor in the well is gradually consumed, the liquid level in the water tank 7 drops, the floating cylinder 136 drops, causing the valve plate 1312 to reverse and reopen the input channel of the corrosion inhibitor in the mixing tank 61, and then the corrosion inhibitor can be replenished until the liquid level in the water tank 7 rises again and the output passage of the mixing tank 61 is closed again.

[0040] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A device for injecting corrosion inhibitor for carbon dioxide flooding oil wells, characterized in that: include: A frame (1), a hopper (4), a water storage tank (5), a mixing mechanism (6), a water return device and a cleaning mechanism (12); The mixing mechanism (6) is installed in the frame (1); the hopper (4) and the water storage tank (5) are connected to the mixing mechanism (6); the water return device is installed on the side wall of the frame (1); and the cleaning mechanism (12) is connected to the water return device; The water return device comprises: a water tank (7), a water return pump (9), a delivery pipe (10) and an extraction pipe (11); the water tank (7) is mounted on the side wall of the frame (1), and the water tank (7) is a hollow structure with an open top; the water return pump (9) is mounted on the cleaning mechanism (12); one end of the delivery pipe (10) is mounted on the output end of the water return pump (9), and the other end of the delivery pipe (10) corresponds to the water tank (7); the extraction pipe (11) is mounted on the suction end of the water return pump (9); The mixing mechanism (6) comprises: a mixing box (61) and a water outlet pipe (68); the mixing box (61) is installed in the frame (1), and the water outlet pipe (68) is installed on the mixing box (61); A flow control mechanism (13) is installed between the mixing mechanism (6) and the water return device, and the flow control mechanism (13) is capable of controlling the output ratio of the fluid in the mixing mechanism (6) and the water return device.

2. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 1, characterized in that: include: A first bracket (2), a second bracket (3); The first bracket (2) and the second bracket (3) are both mounted on the frame (1); the hopper (4) is mounted on the second bracket (3), and the water storage tank (5) is mounted on the first bracket (2); the hopper (4) and the water storage tank (5) are respectively connected to the top of the mixing box (61) via connecting pipes.

3. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 2, characterized in that: The water return device further comprises: a mesh plate (701), a baffle plate (8) and an overflow trough (801); The mesh plate (701) is installed on the top of the water tank (7), and a plurality of mesh holes are arranged in an array on the mesh plate (701); the baffle plate (8) is installed on the water tank (7), and an overflow groove (801) is formed between the baffle plate (8) and the outer wall of the water tank (7).

4. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 3, characterized in that: The cleaning mechanism (12) comprises: a fixed plate (121), a mounting frame (122), a reciprocating screw (123), a first motor (124), a sliding block (125), a slider (126), a moving frame (127), a sliding groove (128), a scraper (129), a driving rod (1210) and a blind groove (1211); There are two fixing plates (121), which are symmetrically mounted on the top of the water tank (7); the mounting frames (122) are symmetrically mounted on the top of the water tank (7), and the straight lines where the centers of the two fixing plates (121) and the straight lines where the centers of the two mounting frames (122) are perpendicular to each other; the two ends of the reciprocating screw (123) are rotatably mounted on the two mounting frames (122); the first motor (124) is mounted on one of the mounting frames (122), and one end of the reciprocating screw (123) is connected to the output end of the first motor (124); the sliding block (125) is mounted on the reciprocating screw The guide screw (123) is provided on the guide screw (123); the slider (126) is fixedly connected to the slider block (125); the slide groove (128) is provided in the movable frame (127), and the slider (126) is slidably installed in the slide groove (128); the scraper (129) is installed on the lower surface of the movable frame (127); there are two driving rods (1210), which are symmetrically installed on both sides of the movable frame (127); there are two blind grooves (1211), which are symmetrically provided on opposite sides of the two fixed plates (121), and the two driving rods (1210) are slidably installed in the two blind grooves (1211) respectively.

5. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 4, characterized in that: A limiting rod (1251) is also installed between the two mounting frames (122), and the limiting rod (1251) passes through the sliding block (125).

6. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 5, characterized in that: The blind groove (1211) comprises: a translation section (12111), a first transition section (12112), a second transition section (12113), a return section (12114), a third transition section (12115) and a flexible baffle (12116); The translation section (12111), the first transition section (12112), the second transition section (12113), the regression section (12114) and the third transition section (12115) are connected in sequence; The flexible baffle (12116) is installed obliquely between the first transition section (12112) and the second transition section (12113).

7. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 6, characterized in that: The mixing mechanism (6) further comprises: a stirring paddle (62), a housing (63), a first gear (64), a second gear (65), a toothed belt (66), and a second motor (67); There are two stirring paddles (62), which are rotatably mounted in the mixing box (61); the housing (63) is mounted on the mixing box (61); the first gear (64) and the second gear (65) are rotatably mounted in the housing (63), and the first gear (64) and the second gear (65) are respectively connected to the two stirring paddles (62); the toothed belt (66) is mounted between the first gear (64) and the second gear (65); the second motor (67) is mounted on the housing (63), and the output end of the second motor (67) is connected to the first gear (64).

8. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 7, characterized in that: The mixing mechanism (6) further comprises: a plurality of limiting wheels (69), each of which is rotatably mounted in the housing (63) and in rolling contact with the toothed belt (66).

9. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 8, characterized in that: The diameter of the first gear (64) is smaller than the diameter of the second gear (65).

10. The device for adding corrosion inhibitor to a carbon dioxide flooding oil well according to claim 9, characterized in that: The flow control mechanism (13) comprises: a flow control box (131), a first inlet (132), an outlet (133), an output pump (134), a side box body (135), a float (136), an extension rod (137), a cross rod (138), a rotating disk (139), a swing rod (1310), a compensation groove (1311), a valve plate (1312), a through hole (1313), a branch pipe (1314) and a second inlet (1315); The end of the water outlet pipe (68) away from the mixing box (61) extends into the flow control box (131); the end of the water outlet pipe (68) extending into the flow control box (131) is a first inlet (132); the outlet (133) is installed on the flow control box (131); the output pump (134) is installed in the frame (1), and the suction end of the output pump (134) is connected to the outlet (133); the side box body (135) is installed on the side wall of the water tank (7), and the side box body (135) is connected to the inner cavity of the water tank (7); the buoy (136) is slidably installed in the side box body (135); the extension rod (137) is installed at the top of the buoy (136), and the extension rod (137) slidably extends out of the top of the side box body (135); the cross bar (138) is hingedly installed on the side wall of the water tank (7); The extension rod (137) is mounted on the rotating disk (139) in rotation on the flow control box (131); the swing rod (1310) is mounted on the rotating disk (139); the compensation groove (1311) is provided on the swing rod (1310), and the cross rod (138) is slidably installed in the compensation groove (1311); the valve plate (1312) is mounted in rotation on the flow control box (131), and the valve plate (1312) is connected to the rotating disk (139); there are two through holes (1313), which are respectively provided on the valve plate (1312); one end of the branch pipe (1314) is connected to the water tank (7), and the other end of the branch pipe (1314) extends into the flow control box (131); the end of the branch pipe (1314) extending into the flow control box (131) is a second inlet (1315); The valve plate (1312) is in contact with the first inlet (132) and the second inlet (1315).

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