Automatic water cutting device for oil storage tank

Abstract

The application provides an automatic water cutting device for an oil storage tank, and particularly relates to the technical field of petroleum and chemical industry, and comprises a vertically arranged buffer cylinder one, which is connected with the oil storage tank through a suction assembly and an oil return assembly, and is connected with an oil-water separation assembly in a detachable mode on the inner side; the oil-water separation assembly comprises a filter assembly arranged in the buffer cylinder one, a rotating structure connected with the filter assembly, and a lifting structure connected with the rotating structure; the lifting structure is movably arranged on a track assembly, and a plurality of oil-water separation assemblies are arranged on the track assembly; a plurality of oil content detection controllers are arranged in the oil storage tank in a detachable mode. The automatic water cutting device for the oil storage tank can efficiently and quickly realize oil-water separation, avoids the deposition of impurities such as oil sludge and sand at the bottom of a dehydrator, basically realizes dehydration in the oil storage tank, and basically realizes a complete oil return process in the dehydrator.

Description

Technical Field

[0001] This invention belongs to the field of petrochemical technology, specifically relating to an automatic water-cutting device for oil storage tanks. Background Technology

[0002] The media stored in petrochemical tanks generally contain oil and water. The water gradually settles to the bottom and must be removed promptly to avoid affecting production and product quality. The water cutter is a new generation product developed to meet the current dehydration needs of petrochemical tanks. Made of stainless steel, it features a reasonable design, simple structure, large drainage capacity, fast oil return speed, strong corrosion resistance, and convenient, safe, and reliable operation. Used in the petroleum and chemical industries, it replaces manual water cutting in oil tanks, achieving automatic water cutting. This significantly reduces the labor intensity of operators and the risk of hydrogen sulfide poisoning that occurs during manual water cutting, while also reducing oil waste and environmental pollution. Furthermore, it meets the regulatory requirements for underground drainage and pipeline systems in petrochemical systems.

[0003] However, the current water cutters still have the following technical problems in use:

[0004] (1) At present, most dehydrators are buffer tank type structures. Water and oil at the bottom of the oil tank enter the buffer tank, settle, and form an oil-water interface. The dehydration valve is controlled by detecting the height of the oil-water interface. However, during the dehydration process, impurities such as sludge and sand at the bottom of the oil tank will also enter the dehydrator and settle at the bottom of the dehydrator. Regular cleaning is required, resulting in a large amount of maintenance.

[0005] (2) When the density difference between oil and water is not significant, the time required to establish the oil-water interface is relatively long, which affects the dehydration rate. For example, the density of heavy crude oil is greater than or equal to 0.931 and less than 0.998 g / cm³. 3 The density of extra-heavy crude oil is greater than or equal to 0.998 g / cm³. 3 This results in water at the bottom of the oil storage tank not being able to completely enter the dehydrator for dehydration, causing a small amount of water to accumulate at the bottom of the oil storage tank, making it impossible to achieve complete dehydration; at the same time, some oil will be mixed in inside the dehydrator and cannot be completely returned to the oil storage tank.

[0006] This solution provides an automatic water-cutting device for oil storage tanks to address the aforementioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to provide an automatic water-cutting device for oil storage tanks, which solves the technical problem of how to achieve oil-water separation efficiently and quickly, avoids the deposition of impurities such as sludge and sand at the bottom of the dehydrator, and basically achieves dehydration in the oil storage tank and a complete oil return process in the dehydrator.

[0008] An automatic water-cutting device for an oil storage tank includes a vertically arranged buffer cylinder. The buffer cylinder is connected to the oil storage tank via a suction assembly and an oil return assembly. The inner side of the buffer cylinder is separately connected to an oil-water separation assembly. The oil-water separation assembly includes a filter assembly disposed inside the buffer cylinder, a rotating structure connected to the filter assembly, and a lifting structure connected to the rotating structure. The lifting structure is movably mounted on a track assembly, and multiple oil-water separation assemblies are disposed on the track assembly.

[0009] It also includes several oil content detection controllers 1 that are separately installed in the oil storage tank and oil content detection controller 2 that are positioned on the filter assembly.

[0010] Preferably, the filter assembly includes a support box with its opening facing upwards, a cover plate that is closed and positioned above the support box by screws, a rotating cylinder whose bottom end is coaxially fixed to the center of the cover plate, and a horizontal rod that is vertically and movably connected to the top end of the rotating cylinder. The bottom end of the rotating cylinder communicates with the interior of the support box, the rotating cylinder is rotatably connected to the horizontal rod, and the upper end face of the support box is sealed to the cover plate by a sealing ring.

[0011] The top end of the rotating drum is rotatably and sealed to one end of the suction pipe, and the other end of the suction pipe is connected to an air pump.

[0012] The support box, the cover plate, and the rotating cylinder are all metal mesh structures. The outer side of the metal mesh structure is covered with a hydrophilic ceramic membrane, the outer side of the hydrophilic ceramic membrane is coated with a hydrophilic polymer, the outer side of the hydrophilic polymer is covered with a polyvinylidene fluoride microfiltration membrane, and the interior of the support box is provided with multiple hydrogel particles.

[0013] The metal mesh structure has several through holes with an inner diameter of 1-2 mm, and the metal material used is iron, aluminum, etc.

[0014] Preferably, the rotating structure includes a first synchronous pulley coaxially disposed at the upper end of the rotating drum, a second synchronous pulley coaxially connected to the drive motor, and a synchronous belt drivingly connected to the first synchronous pulley and the second synchronous pulley, wherein the drive motor is fixed on the horizontal bar.

[0015] Preferably, the lifting structure includes lifting cylinders respectively disposed at both ends of the horizontal rod, a movable seat connected to the lifting cylinders, and a power wheel disposed at the bottom end of the movable seat, wherein the free end of the lifting cylinder is fixedly connected to the end of the horizontal rod.

[0016] Preferably, the suction assembly includes a suction pump connected to the bottom of the oil storage tank, a suction pipe connected to the suction pump at one end, a filter disposed on the suction pipe, and the other end of the suction pipe connected to the buffer cylinder.

[0017] The suction pump, located at the bottom of the oil storage tank and controlled by the oil content detection controller, can effectively remove moisture from the bottom of the tank. The filter, on the other hand, pre-filters out some of the sludge and sand.

[0018] Preferably, the oil return assembly includes an oil return pipe with one end connected to the bottom end of the buffer cylinder, an oil return pump installed on the oil return pipe, the other end of the oil return pipe connected to the oil storage tank, and a valve installed on the oil return pipe.

[0019] Preferably, the outer side of the support box is provided with a plurality of scrapers arranged in a circular array, and the outer end face of the scrapers is tangent to the inner side of the buffer cylinder.

[0020] Preferably, the hydrophilic ceramic membrane is a hydrophilic modified alumina membrane or a zirconia membrane, and the hydrophilic polymer is any one of polydopamine, polyethyleneimine, polyacrylic acid, and polyethylene glycol.

[0021] Preferably, the track assembly includes two parallel tracks, the drive wheel is movably mounted on the tracks, and a buffer cylinder is provided between the two tracks.

[0022] The beneficial effects of this invention are as follows:

[0023] (1) The filtering component in this solution achieves the following technical effects:

[0024] First, the support box, cover plate and rotating cylinder in this solution are all made of metal mesh structure, which helps to increase strength. On their outer surface, hydrophilic ceramic membrane, hydrophilic polymer and polyvinylidene fluoride microfiltration membrane are coated from the inside to the outside, which can maximize the hydrophilic and oleophobic process, not only keeping the filter components relatively clean, but also making it easy to clean and replace.

[0025] Secondly, under the action of the air pump, air is drawn from the rotating drum, which helps to achieve negative pressure inside the support box and the rotating drum, thus facilitating efficient filtration of oil-water mixtures.

[0026] Third, hydrogel is provided on the inside of the support box to achieve full absorption of water molecules;

[0027] (2) It is equipped with a rotating structure and a lifting structure, which work together with the filter components to achieve the following technical effects:

[0028] Firstly, the rotation of the filter components helps to stir the oil and water in the first buffer tank, causing impurities such as sludge and sand in the first buffer tank to float up and flow back into the oil storage tank, avoiding residue in the first buffer tank. In addition, when the oil return ends, the rotation also has a centrifugal effect, which shakes off any oil that may be adhering to the filter components and lets it fall back into the first buffer tank.

[0029] Secondly, it is equipped with a lifting structure, which can come into contact with the oil-water mixture at the top and bottom of the buffer cylinder, thereby achieving full water absorption of the upper and lower parts of the oil-water mixture and avoiding the problem of water residue in the past.

[0030] Third, it is equipped with scrapers. When the oil return is about to end, the scrapers can contact various positions on the inner side of the buffer cylinder under the action of rotation and lifting, thereby scraping the oil on the inner side of the buffer cylinder downward to achieve full oil return.

[0031] (3) A track assembly is provided. On the one hand, multiple oil-water separation components can move back and forth along the track. Under the action of the lifting structure, the filter components are removed from the first buffer cylinder, and people can remove the screws on the cover plate and replace the hydrogel in the support box. On the other hand, a second buffer cylinder can also be set between the tracks. When there are many oil storage tanks, the water cutting process of multiple oil storage tanks can be carried out at the same time.

[0032] (4) The water-cutting device set in this scheme is completely different from the existing dehydrator through the improvement design of the existing technical principle. It basically solves the technical problems raised in the background technology and has excellent technical effect. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the working state of the sealed water cutter in this invention.

[0034] Figure 2 This is a schematic diagram of the closed water cutter in this invention.

[0035] Figure 3 This is a schematic diagram of the connection structure between the filter component and the rotary lifting component in this invention.

[0036] Figure 4 This is an exploded view of the filter assembly in this invention.

[0037] Figure 5 This is a schematic diagram of the structure of the buffer cylinder and the support box in this invention.

[0038] Figure 6 This is a schematic diagram of the connection structure of the filter component, the rotary lifting component, and the buffer cylinder II in this invention.

[0039] The attached diagram is labeled as follows: 1. Track; 2. Movable seat; 3. Lifting cylinder; 4. Buffer cylinder one; 5. Return oil pump; 6. Return oil pipe; 7. Suction pipe; 8. Suction pump; 9. Oil storage tank; 10. Filter; 11. Baffle plate; 12. Air pump; 121. Discharge pipe; 13. Rotary drum; 130. Horizontal bar; 131. Cover plate; 132. Support box; 133. Scraper; 134. Screw; 14. Drive motor; 15. Buffer cylinder two. Detailed Implementation

[0040] To more clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0041] See Figures 1-6 An automatic water-cutting device for an oil storage tank includes a vertically arranged buffer cylinder 4. The buffer cylinder 4 is connected to the oil storage tank 9 through a suction component and an oil return component. The inner side of the buffer cylinder 4 is separately connected to an oil-water separation component. The oil-water separation component includes a filter component disposed inside the buffer cylinder 4, a rotating structure connected to the filter component, and a lifting structure connected to the rotating structure. The lifting structure is movably disposed on a track component, and multiple oil-water separation components are disposed on the track component.

[0042] It also includes several oil content detection controllers (I) separately installed in the oil storage tank 9, and oil content detection controllers (II) positioned on the filter assembly. For the sake of simplifying the design, oil content detection controllers I and II are not described in detail in the attached drawings, but are hereby explained.

[0043] Among them, multiple oil content detection controllers are arranged at different locations in the oil storage tank 9, and multiple oil content detection controllers are also arranged at different locations inside the buffer cylinder 4. For example, the height position of the control sensor can be adjusted by controlling the length of the sensor data line.

[0044] It should be noted that the oil content detection controller consists of a liquid column resonant oil content detection sensor and a controller. The sensor is a monolithic structure, with a vibrating plate in direct contact with the medium. It is connected to the drive element via a transmission rod, generating resonance with the medium. The resonant frequency and amplitude of the vibrating plate will change depending on the oil content in the water, thus detecting the oil content. To prevent the sensor from being contaminated by oil sludge, a diamond protective film is coated on the sensor surface. This is a prior art sensor, and its working principle will not be detailed further.

[0045] By using the oil content detection controller, the working conditions inside the oil tank can be clearly understood, and the status of the dehydration system can be judged in a timely manner, which brings convenience to production and improves work efficiency.

[0046] The filter assembly includes a support box 132 with its opening facing upwards, a cover plate 131 that is closed and positioned above the support box 132 by screws 134, a rotating cylinder 13 whose bottom end is coaxially fixed to the center of the cover plate 131, and a horizontal rod 130 that is vertically and movably connected to the top end of the rotating cylinder 13. The bottom end of the rotating cylinder 13 communicates with the inside of the support box 132, and the rotating cylinder 13 is rotatably connected to the horizontal rod 130. The upper end face of the support box 132 is sealed to the cover plate 131 by a sealing ring.

[0047] The top of the rotating drum 13 is rotatably and sealed to one end of the suction pipe, and the other end of the suction pipe is connected to the air pump 12; more preferably, a barometer is installed on the suction pipe to determine the negative pressure data.

[0048] The support box 132, cover plate 131 and rotating cylinder 13 are all metal mesh structures. The outside of the metal mesh structure is covered with a hydrophilic ceramic membrane. The outside of the hydrophilic ceramic membrane is coated with a hydrophilic polymer. The outside of the hydrophilic polymer is covered with a polyvinylidene fluoride microfiltration membrane. Multiple hydrogel particles are arranged inside the support box 132.

[0049] More preferably, a baffle plate 11 is coaxially and vertically arranged at the upper end of the rotating drum 13 to prevent oil and water from splashing in the buffer cylinder 4. The air pump 12 is connected to the discharge pipe 121 for exhausting air.

[0050] When the filter components in this solution are immersed in oil and water, their surface is covered by a strong layer of water molecules (hydration layer). Oil droplets cannot replace this water film to directly contact the material surface, thus exhibiting a very large underwater oil contact angle (usually >150°), making them very easy to roll off or be blocked.

[0051] The material itself, or the substrate used as a coating, needs to have interconnected, sufficiently large pores to allow water to flow through, while relying on the surface hydration layer rather than simply the pore size to block oil droplets.

[0052] In this design, the coating structure on the outside of the metal mesh structure allows water to continuously permeate downwards when oily wastewater comes into contact with the membrane surface, while the surface remains superoleophobic, trapping oil on the surface to achieve oil-water separation. Furthermore, due to the membrane's potential oleophobicity, oil can never contaminate the membrane surface, making it suitable for applications with low water content and high oil content.

[0053] The rotating structure includes a first synchronous pulley coaxially disposed at the upper end of the rotating drum 13, a second synchronous pulley coaxially connected to the drive motor 14, and a synchronous belt drivingly connected to the first and second synchronous pulleys. The drive motor 14 is fixed on the horizontal bar 130.

[0054] To simplify the design, synchronous pulley one and synchronous pulley two are not shown in the attached drawings, but this is easily implemented by those skilled in the art and will not be described in detail here.

[0055] The lifting structure includes lifting cylinders 3 respectively installed at both ends of the horizontal rod 130, a movable seat 2 connected to the lifting cylinders 3, and a power wheel installed at the bottom of the movable seat 2. The free end of the lifting cylinder 3 is fixedly connected to the end of the horizontal rod 130. For the sake of simplifying the design, the power wheel is not shown in the attached drawings, but this does not affect the implementation of this solution.

[0056] The suction assembly includes a suction pump 8 connected to the bottom of the oil storage tank 9, a suction pipe 7 connected to the suction pump 8 at one end, a filter 10 installed on the suction pipe 7, and the other end of the suction pipe 7 connected to the buffer cylinder 4.

[0057] The oil return assembly includes an oil return pipe 6 connected at one end to the bottom of the buffer cylinder 4, an oil return pump 5 installed on the oil return pipe 6, and the other end of the oil return pipe 6 connected to the oil storage tank 9. A valve is also installed on the oil return pipe 6.

[0058] More preferably, valve structures are installed in all the pipelines involved in this scheme. For example, valve structures are also designed on the suction pipe 7. They are not shown in the attached drawings.

[0059] Multiple scrapers 133 are arranged in a circular array on the outer side of the support box 132, and the outer end face of the scraper 133 is tangent to the inner side of the buffer cylinder 4. When the scraper 133 is working, the support box 132 is adjusted to the top of the buffer cylinder 4, and then rotated and lowered to scrape the oil on the inside of the buffer cylinder 4 into the return oil pipe 6, and finally back into the oil storage tank 9.

[0060] The hydrophilic ceramic membrane is a hydrophilic modified alumina membrane or a zirconia membrane, and the hydrophilic polymer is any one of polydopamine, polyethyleneimine, polyacrylic acid, and polyethylene glycol.

[0061] The track assembly includes two parallel tracks 1, a drive wheel that moves on the tracks 1, and a buffer cylinder 15 between the two tracks 1.

[0062] The specific working process of this invention:

[0063] Existing technologies typically employ dehydrators. In this solution, to avoid the problems present in existing dehydrators, a buffer cylinder is designed, allowing the filter components to contact the buffer cylinder separately. This results in a combination of gravity dehydration separation, filtration, and collision separation effects, leading to a separation effect superior to existing dehydrators. Experimental verification shows that the existing buffer cylinder is essentially free of sludge, sand, etc. Meanwhile, the water residue in the original oil storage tank 9 is 0.1-0.3%, and the oil residue rate in the buffer cylinder is 0.22-0.35%, essentially achieving clean oil-water separation.

[0064] In this design, a filter assembly is provided. The support box 132, cover plate 131 and rotating cylinder 13 in this design are all made of metal mesh structure, which helps to increase strength. On their outer surface, a hydrophilic ceramic membrane, a hydrophilic polymer and a polyvinylidene fluoride microfiltration membrane are coated from the inside to the outside in sequence, which can maximize the hydrophilic and oleophobic process, not only keeping the filter assembly relatively clean, but also making it easy to clean and replace.

[0065] This solution sets up a multi-layer water filtration membrane on the outside of the metal mesh structure, making full use of the oleophobic properties to achieve oil-water separation. Water molecules pass through the polyvinylidene fluoride microfiltration membrane, hydrophilic polymer, hydrophilic ceramic membrane and metal mesh structure in sequence, enter the interior of the support box 132, and then come into contact with hydrogel particles. With the effect of negative pressure, the oil-water filtration efficiency is greatly improved and oil adhesion is avoided.

[0066] When the filter assembly rotates and rises, the air pump 12 works simultaneously. Under the action of the air pump 12, air is drawn from the rotating drum 13, which helps to achieve negative pressure inside the support box 132 and the rotating drum 13, thereby facilitating efficient filtration of oil-water mixtures. At the same time, the negative pressure also makes the connection between the support box 132 and the cover plate 131 tighter, which helps to seal the seal. Hydrogel is provided on the inner side of the support box 132, which enables the full absorption of water molecules. After a certain period of time, the expanded hydrogel is replaced, and the oil-water separation work is carried out again.

[0067] Equipped with a rotating and lifting structure, it works in conjunction with the filter assembly. The rotation of the filter assembly helps to stir the oil and water in the buffer cylinder 4, causing impurities such as sludge and sand in the buffer cylinder 4 to float up and flow back into the oil storage tank 9, avoiding residue in the buffer cylinder 4. In addition, when the oil return is finished, the rotation also has a centrifugal effect, which shakes off any oil that may be adhering to the filter assembly and lets it fall back into the buffer cylinder 4.

[0068] Equipped with a lifting structure, it can contact the oil-water mixture at the top and bottom of the buffer cylinder 4, thereby achieving full water absorption of the upper and lower parts of the oil-water mixture and avoiding the problem of water residue in the past.

[0069] The system is equipped with a scraper 133. When the oil return is about to end, the scraper 133 can contact various positions on the inner side of the buffer cylinder 4 under the action of rotation and lifting, thereby scraping the oil on the inner side of the buffer cylinder 4 downward to achieve full oil return.

[0070] The system is equipped with a track assembly. On the one hand, multiple oil-water separation components can reciprocate along the track 1. Under the action of the lifting structure, the filter components are moved away from the buffer cylinder 4, and people can remove the screws 134 on the cover plate 131 to replace the hydrogel in the support box 132. On the other hand, a buffer cylinder 2 15 can also be set between the tracks 1. When there are many oil storage tanks 9, the water cutting process of multiple oil storage tanks 9 can be carried out at the same time.

[0071] The technical features of this invention not described can be implemented by or using existing technology, and will not be repeated here. Of course, the above description is not a limitation of this invention, and this invention is not limited to the examples above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this invention should also be within the protection scope of this invention.

Claims

1. An automatic water-cutting device for an oil storage tank, comprising a vertically arranged buffer cylinder (4), characterized in that, The buffer cylinder (4) is connected to the oil storage tank (9) through a suction component and an oil return component. The inner side of the buffer cylinder (4) is separately connected to the oil-water separation component. The oil-water separation component includes a filter component disposed inside the buffer cylinder (4), a rotating structure connected to the filter component, and a lifting structure connected to the rotating structure. The lifting structure is movably disposed on a track component, and multiple oil-water separation components are disposed on the track component. It also includes several oil content detection controllers 1 and 2, which are separately installed in the oil storage tank (9) and positioned on the filter assembly; The filter assembly includes a support box (132) with its opening facing upwards, a cover plate (131) that is closed and positioned above the support box (132) by screws (134), a rotating cylinder (13) whose bottom end is coaxially fixed to the center of the cover plate (131), and a horizontal rod (130) that is vertically and movably connected to the top end of the rotating cylinder (13). The bottom end of the rotating cylinder (13) is connected to the inside of the support box (132), and the rotating cylinder (13) is rotatably connected to the horizontal rod (130). The upper end face of the support box (132) is sealed to the cover plate (131) by a sealing ring. The top end of the rotating cylinder (13) is rotatably and sealed to one end of the suction pipe, and the other end of the suction pipe is connected to the air pump (12). The support box (132), the cover plate (131) and the rotating cylinder (13) are all metal mesh structures. The outside of the metal mesh structure is covered with a hydrophilic ceramic membrane. The outside of the hydrophilic ceramic membrane is coated with a hydrophilic polymer. The outside of the hydrophilic polymer is covered with a polyvinylidene fluoride microfiltration membrane. The support box (132) is provided with multiple hydrogel particles inside. The rotating structure includes a first synchronous wheel coaxially disposed on the upper end of the rotating drum (13), a second synchronous wheel coaxially connected to the drive motor (14), and a synchronous belt drivingly connected to the first synchronous wheel and the second synchronous wheel. The drive motor (14) is fixed on the horizontal rod (130). The lifting structure includes lifting cylinders (3) respectively disposed at both ends of the horizontal rod (130), a movable seat (2) connected to the lifting cylinders (3), and a power wheel disposed at the bottom end of the movable seat (2). The free end of the lifting cylinders (3) is fixedly connected to the end of the horizontal rod (130).

2. The automatic water-cutting device for an oil storage tank according to claim 1, characterized in that, The suction assembly includes a suction pump (8) connected to the bottom of the oil storage tank (9), a suction pipe (7) connected to the suction pump (8) at one end, and a filter (10) set on the suction pipe (7). The other end of the suction pipe (7) is connected to the buffer cylinder (4).

3. The automatic water-cutting device for an oil storage tank according to claim 1, characterized in that, The oil return assembly includes an oil return pipe (6) with one end connected to the bottom end of the buffer cylinder (4), an oil return pump (5) installed on the oil return pipe (6), the other end of the oil return pipe (6) being connected to the oil storage tank (9), and a valve being installed on the oil return pipe (6).

4. The automatic water-cutting device for an oil storage tank according to claim 1, characterized in that, The outer side of the support box (132) is provided with a plurality of scrapers (133) arranged in a ring array, and the outer end face of the scraper (133) is tangent to the inner side of the buffer cylinder (4).

5. An automatic water-cutting device for an oil storage tank according to claim 1, characterized in that, The hydrophilic ceramic membrane is a hydrophilic modified alumina membrane or a zirconia membrane, and the hydrophilic polymer is any one of polydopamine, polyethyleneimine, polyacrylic acid, and polyethylene glycol.

6. The automatic water-cutting device for an oil storage tank according to claim 1, characterized in that, The track assembly includes two parallel tracks (1), the power wheel is moved on the track (1), and a buffer cylinder (15) is provided between the two tracks (1).

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