Desulfurization and corrosion prevention treatment system and process for oilfield produced wastewater

Abstract

The present application relates to oilfield wastewater treatment technical field, disclose a desulfurization corrosion prevention treatment system and process of oilfield produced wastewater, the treatment system includes tower body, tower plate, float valve, counterweight sleeve and flow guide, the tower body is provided with exhaust port, liquid outlet, liquid inlet and air inlet; The tower plate is arranged in the tower body, and the tower plate is provided with valve hole; The float valve includes sliding rod and valve plate, the sliding rod is arranged on the valve plate and is arranged on the tower plate, and the valve plate is located above the valve hole; The counterweight sleeve is arranged on the sliding rod, and the weight increases gradually according to the set level, and the counterweight sleeve can be separated from the tower plate; The elastic push assembly is arranged between the sliding rod and the counterweight sleeve, and the elastic push assembly provides the lifting force for the counterweight sleeve; The outlet weir is located on the liquid outflow side of the tower plate, the inlet weir is located on the liquid inflow side of the lower tower plate, and the flow guide is arranged on the tower plate and is used to guide the liquid flow on the tower plate.The present application can reduce the opening difference of the float valve on the tower plate, make the float valve air outlet more uniform, and be beneficial to the stable operation of gas-liquid mass transfer.

Description

Technical Field

[0001] This invention relates to the field of oilfield wastewater treatment technology, specifically to a desulfurization and corrosion prevention treatment system and process for oilfield produced wastewater. Background Technology

[0002] Oilfield wastewater is characterized by high oil and solids content and a tendency to scale. Steam stripping is a common treatment method for oilfield wastewater. Floating valve plate towers are highly efficient gas-liquid mass transfer devices for treating sulfides (such as H2S) in oilfield wastewater, and are widely used in the stripping desulfurization process for sulfur-containing wastewater in the petrochemical industry. They use steam or air as the gaseous medium to achieve countercurrent contact with the wastewater within the tower, transferring volatile sulfides from the liquid phase to the gas phase, thereby completing the removal.

[0003] The floating valve plate tower features large valve orifices and strong anti-clogging ability, allowing oil-sulfur mixtures to pass smoothly through the valve orifices. When treating oilfield wastewater by stripping, the floating valves in the floating valve plate tower can automatically adjust their opening, providing high operational flexibility (50%-120%) and adapting to fluctuations in water volume. Furthermore, the tower plates inside the tower are removable for cleaning, making maintenance convenient and avoiding frequent shutdowns.

[0004] However, existing floating valve plate towers also have some drawbacks. For example, when oilfield wastewater flows through a single-layer tray in a floating valve plate tower, it must overcome the resistance caused by multiple floating valves on the tray, which will result in a certain slope of the liquid surface on the tray. Specifically, a certain liquid level gradient will appear on the liquid inlet and outlet sides of the tray. This will cause the floating valves at higher liquid levels to open less when the gas opens, while the floating valves at lower liquid levels will open more, resulting in a large difference in the opening of the floating valves at the two locations. This large difference in the opening of the floating valves can affect the gas output at the corresponding locations, thus making the gas output at each floating valve on the tray inconsistent. It is not easy to maintain uniform gas output from each floating valve. Uneven gas output from the floating valves may lead to a deterioration in the mass transfer effect between the gas and the oilfield wastewater, affecting the stable operation of gas-liquid mass transfer, and consequently, the desulfurization effect of the oilfield wastewater on the tray at different floating valves. Summary of the Invention

[0005] This invention provides a desulfurization and corrosion prevention treatment system and process for oilfield produced wastewater, which can reduce the opening difference of the float valve on the tower plate, making the gas outlet of the float valve more uniform, which is conducive to maintaining stable operation of gas-liquid mass transfer.

[0006] The desulfurization and corrosion prevention treatment system for oilfield produced wastewater of the present invention adopts the following technical solution: The desulfurization and corrosion protection system for oilfield produced wastewater includes a tower body, tower plates, float valves, counterweight sleeves, elastic propulsion components, and flow guides. The tower body has exhaust and liquid outlets at the top and bottom, respectively, and liquid and air inlets on the side walls, with the liquid inlet near the top and the air inlet near the bottom. Multiple tower plates are evenly distributed within the tower body, each with multiple evenly distributed valve holes. The float valves correspond to the valve holes and include sliding rods and valve plates. Multiple sliding rods are evenly distributed around the circumference of the valve holes on the valve plates, passing through the tower plates parallel to the central axis of the valve holes. The valve plates are located above the valve holes. The counterweight sleeve is slidably mounted on the tower plate and fitted onto the counterweight sleeve. On the sliding rod, multiple counterweight sleeves are arranged in progressively heavier levels, and the counterweight sleeves are configured to detach from the top of the tray. An elastic pushing component is disposed between the sliding rod and the counterweight sleeves, and is configured to lift some or all of the counterweight sleeves when the sliding rod rises. The elastic pushing component includes a protrusion, a stepped block, and a spring. The protrusion is disposed on the inner wall of the counterweight sleeve, and a transverse groove is formed on the side wall of the sliding rod. The stepped block is slidably disposed in the transverse groove, and the spring is disposed between the transverse groove and the stepped block. The spring is configured to allow the small end face of the stepped block to extend out of the transverse groove opening. The small end face of the stepped block is located below the protrusion, and the side of the stepped block contacts the protrusion. A flow guide is disposed on the tray to guide the flow of liquid on the tray.

[0007] Furthermore, the counterweight sleeve includes a sleeve body and a counterweight ring. The sleeve body is sleeved on the sliding rod, and the counterweight ring is sleeved on the sliding rod and fixed to the top of the sleeve body. The radius of the counterweight ring is larger than the radius of the hole in the sleeve body. The outer diameters of the counterweight rings on multiple counterweight sleeves are different, and the weight of the multiple counterweight rings gradually increases according to the set weight level.

[0008] Furthermore, a limiting member is provided at the bottom of the valve plate. The limiting member is configured to restrict the range of movement of the valve plate in a direction parallel to the central axis of the valve hole, and to keep the valve plate and the valve hole coaxial.

[0009] Furthermore, the limiting component includes a valve leg and a guide block. The valve leg is fixed to the bottom of the valve plate, and a limiting groove is formed on the valve hole wall. The valve leg corresponds to the limiting groove. The guide block is fixed on the side of the valve leg facing the valve hole wall, and the side of the guide block away from the valve leg is inserted into the corresponding limiting groove.

[0010] Furthermore, the float valve also includes a cleaning element disposed on the valve plate and configured to clean the valve plate when the airflow pushes the valve plate up. The cleaning element has a dead zone relief structure, which reduces the gas-liquid mass transfer dead zone above the valve plate when the cleaning element cleans the valve plate.

[0011] Furthermore, the cleaning component includes a first scraper, a support rod, and a second scraper. The first scraper is fixed to one end of the sliding rod that protrudes from the tower plate. The ends of multiple first scrapers away from their corresponding sliding rods are connected to the same first center point. The dead zone relief structure is disposed on the first scraper. The support rod passes through the valve hole, and the second scraper is connected to the end of the support rod that extends out of the valve hole. There are multiple support rods and multiple second scrapers. The multiple support rods and multiple second scrapers are evenly distributed along the circumference of the valve hole. The ends of the multiple second scrapers that are away from the corresponding support rods are connected to the same second center point. Multiple support rods correspond one-to-one with multiple sliding rods and are all parallel to the central axis of the valve hole. Multiple first scraper rods and multiple second scraper rods correspond one-to-one and are parallel to each other. The first scraper rods and their corresponding second scraper rods are spaced apart. The valve plate is clamped in the gap cavity formed by the multiple first scraper rods and multiple second scraper rods. An elastic connecting piece is provided between the support rods and their corresponding sliding rods. The elastic connecting piece is configured to make the second scraper rods and the first scraper rods tend to move closer to each other, so that the first scraper rods abut against the outer top surface of the valve plate and the second scraper rods abut against the inner bottom surface of the valve plate. The limiting slide groove is provided with multiple grooves, and the valve leg is provided with multiple valve legs. The multiple valve legs are evenly distributed around the central axis of the valve hole on the inner bottom surface of the valve plate. The limiting slide groove is a spiral groove, and multiple spiral grooves are evenly distributed along the circumference of the valve hole. The spiral grooves do not interfere with each other. The multiple spiral grooves correspond to the multiple valve legs respectively. The guide block is inserted into the spiral groove corresponding to the valve leg.

[0012] Furthermore, the dead zone mitigation structure includes a guide groove and an air hole. The guide groove is formed at the bottom of the first scraper, one end of which extends to the sliding rod and leads to the outside of the valve plate, and the other end communicates with the guide grooves on other first scrapers. The air hole is formed at the bottom of the guide groove.

[0013] Furthermore, the valve plate is a spherical panel, and the first scraper and the second scraper are arc-shaped rods adapted to the outer top surface and inner top surface of the valve plate.

[0014] The desulfurization and corrosion prevention treatment process for oilfield produced wastewater of the present invention adopts the following technical solution: The desulfurization and corrosion prevention treatment process for oilfield produced wastewater, applied to the aforementioned oilfield produced wastewater desulfurization and corrosion prevention treatment system, includes the following steps: Step 1: The air inlet is connected to an external air supply device through a pipe, the liquid inlet is connected to an external oilfield wastewater supply source through a pipe, and the exhaust port and the liquid outlet are connected to an external purification device through pipes; Step 2: The oilfield wastewater entering the tower body from the inlet enters the inlet weir, then overflows from the inlet weir and flows to the tower plate. When the liquid level of the oilfield wastewater near the outlet weir is above the outlet weir, the oilfield wastewater flows through the outlet weir to the downcomer and enters the inlet weir of the lower tower plate. The above process is repeated until it is discharged from the outlet. Step 3: The steam entering the tower body from the inlet passes through the valve holes on the multi-layer tower plates in sequence from the bottom tower plate until it enters the exhaust port. When the steam passes through the valve holes, it exerts a thrust on the valve plate.

[0015] The beneficial effects of this invention are: The desulfurization and corrosion prevention treatment system for oilfield produced wastewater of the present invention introduces oilfield wastewater and gas into the tower body in the same way as the existing floating valve plate tower introduces liquid and gas, and will not be described in detail here. When gas passes through the valve orifice, it pushes the corresponding valve plate to rise. Because the hydraulic pressure on the valve plate near the outlet weir is lower than that near the inlet weir, when the valve plate at the low liquid level rises, the hydraulic pressure on the corresponding counterweight sleeve is also lower due to the lower hydraulic pressure. Therefore, when the valve plate rises, the elastic push component can drive most or all of the counterweight sleeves to rise, resulting in a larger overall weight of the float valve at the low liquid level. Conversely, when the valve plate rises at the high liquid level, the hydraulic pressure on the corresponding counterweight sleeve is higher due to the higher hydraulic pressure. This higher hydraulic pressure causes the heavier counterweight sleeves to remain stationary, with only a portion of the lighter counterweight sleeves rising under the action of the elastic push component, resulting in a smaller overall weight of the float valve at the high liquid level. Furthermore, since the hydraulic pressure on the valve plate at the low liquid level is less than that on the valve plate at the high liquid level, the airflow can more easily push the valve plate at the low liquid level to rise, and the height it rises is also greater. However, since the overall weight of the float valve at the low liquid level is greater than that of the float valve at the high liquid level, the difference between the height the valve plate at the low liquid level rises and the height the valve plate at the high liquid level rises is smaller. Compared with existing float valve plate towers, the opening difference of the float valves in this invention is smaller, which makes the gas outlet of the float valves on the tower plate more uniform when the gas enters the upper tower plate, and thus more conducive to maintaining stable gas-liquid mass transfer operation.

[0016] Furthermore, when the valve plate is raised, it can drive the guide block to move via the valve legs, thereby causing the guide block to slide along the corresponding spiral groove. When the guide block slides along the spiral groove, it can drive the valve plate to rotate. When the valve plate rotates, it can generate relative sliding with the first scraper and the second scraper. Since the first scraper and the second scraper are in contact with the outer top surface and the inner bottom surface of the valve plate, respectively, the first scraper and the second scraper can scrape away the impurities deposited on the outer top surface and the inner bottom surface of the valve plate. This not only extends the service life of the valve plate and reduces the cost of frequent valve plate cleaning, thus reducing the treatment cost of oilfield wastewater by this invention, but also reduces the impact of impurities on the weight of the valve plate and avoids affecting the opening degree of the valve plate due to impurities.

[0017] Furthermore, when the gas enters the area above the tower plate through the valve orifice, some of the gas enters the guide groove and flows out through the air holes on the guide groove. This causes the first scraper covering the valve plate to generate bubbles, and also causes bubbles to form in the corresponding area directly above the valve plate. This improves the uniformity of gas distribution in the liquid on the tower plate, avoids the formation of a gas-liquid mass transfer dead zone directly above the valve plate due to the lack of bubble generation, and improves the gas-liquid contact efficiency in this invention, thereby improving the desulfurization efficiency of this invention. At the same time, the airflow in the guide groove can also blow away the impurities scraped off by the first scraper, reducing the residue of impurities on the valve plate.

[0018] The desulfurization and corrosion prevention treatment process for oilfield produced wastewater of the present invention has the advantages of clear steps and convenient operation. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A cross-sectional three-dimensional structural diagram of the desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the tower plate in the desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in an embodiment of the present invention. Figure 3 A top view of a tower plate in a desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in an embodiment of the present invention; Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure along the AA direction; Figure 5 for Figure 4 A magnified structural diagram of part B in the middle section; Figure 6 A schematic diagram of the structure of a float valve in a desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in an embodiment of the present invention; Figure 7 An exploded structural diagram of a float valve in an oilfield produced wastewater desulfurization and corrosion prevention treatment system provided in an embodiment of the present invention; Figure 8 A top view of a float valve in an oilfield produced wastewater desulfurization and corrosion prevention treatment system provided in an embodiment of the present invention; Figure 9 for Figure 8 A schematic diagram of the cross-sectional structure along the CC direction; Figure 10 for Figure 9 A magnified structural diagram of section D; Figure 11 A schematic diagram of the structure of a tower plate in a desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in another embodiment of the present invention; Figure 12 A schematic diagram of the structure of a float valve in a desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in another embodiment of the present invention; Figure 13 A side view of a float valve in a desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in another embodiment of the present invention.

[0021] In the picture: 100. Tower body; 101. Exhaust port; 102. Drain port; 103. Liquid inlet; 104. Air inlet; 200, Tray; 210, Valve Hole; 211, Limiting Slide Groove; 300, float valve; 310, sliding rod; 320, valve plate; 330, limiting component; 331, valve leg; 332, guide block; 340, first scraper; 341, guide groove; 342, air hole; 350, support rod; 360, second scraper; 370, elastic connecting piece; 400. Counterweight sleeve; 410. Sleeve body; 420. Counterweight ring; 510. Protrusion; 520. Step block; 530. Spring; 610. Outlet weir; 620. Inlet weir; 630. Downcomer. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] like Figures 1 to 13 As shown in the figure, the desulfurization and corrosion prevention treatment system for oilfield produced wastewater provided in this embodiment of the invention includes a tower body 100 and tower plates 200. The tower body 100 can be a closed cylindrical structure. An exhaust port 101 and a liquid drain port 102 are respectively provided at the top and bottom of the tower body 100. An inlet 103 and an air inlet 104 are provided on the side wall of the tower body 100. The inlet 103 is located near the top of the tower body 100, and the air inlet 104 is located near the bottom of the tower body 100. The exhaust port 101 and the liquid drain port 102 can be connected to an external purification device via pipes. The external purification device can be any existing equipment capable of cleaning and purifying wastewater and exhaust gas. The inlet 103 is connected to an external oilfield wastewater supply device via a pipe, and the air inlet 104 is connected to an external air supply device via a pipe. Multiple tower plates 200 are provided, and these multiple tower plates 200 can be evenly arranged within the tower body 100 along its length.

[0026] When the tower body 100 is in a vertical position, all the tower plates 200 are in a horizontal position. Valve holes 210 are provided on the tower plates 200, and there are multiple valve holes 210 evenly distributed on the tower plates 200.

[0027] The present invention also includes a float valve 300, a counterweight sleeve 400, an elastic actuation assembly, and a flow guide.

[0028] Multiple float valves 300 are provided, each corresponding to a plurality of valve holes 210. Each float valve 300 includes a sliding rod 310 and a valve plate 320. One end of the sliding rod 310 is fixed to the edge of the valve plate 320, and the other end passes through the tray 200 along a direction parallel to the central axis of the valve hole 210 (e.g., ...). Figures 11 to 13 (As shown). The valve plate 320 is located above the valve hole 210 and is coaxially arranged with the valve hole 210.

[0029] Specifically, the sliding rod 310 can be a long rod with its length parallel to the central axis of the valve hole 210. The tower plate 200 has through holes axially parallel to the valve hole 210, located around the valve hole 210. Multiple through holes are provided, evenly distributed around the circumference of the valve hole 210. Multiple sliding rods 310 are provided, each corresponding to one through hole and passing through the corresponding through hole, allowing the sliding rod 310 to slide axially along the corresponding through hole.

[0030] The valve plate 320 can be a cone-shaped or conical cover plate disposed above the valve hole 210, and the coverage area of ​​the valve plate 320 can cover the valve hole 210.

[0031] The counterweight sleeve 400 can be a sleeve with a certain weight. Specifically, there are multiple counterweight sleeves 400, and the weight of the multiple counterweight sleeves 400 increases progressively according to a set level. The counterweight sleeves 400 are configured to be able to detach from the top of the tray 200.

[0032] Specifically, multiple counterweight sleeves 400 are inserted into multiple perforations and can slide along the axial direction of the perforations. Each counterweight sleeve 400 is fitted onto a sliding rod 310 within its corresponding perforation. Each counterweight sleeve 400 has a baffle at its top, allowing it to be suspended from the tray 200. The baffle ensures that the counterweight sleeve 400 can only detach from the tray 200 from above, preventing it from slipping off.

[0033] An elastic pushing component is disposed between the sliding rod 310 and the counterweight sleeve 400. This component is configured to provide a lifting force to the rising counterweight sleeve 400 when the sliding rod 310 rises. The elastic pushing component may include a protrusion 510, a step block 520, and a spring 530. The protrusion 510 may be a boss, disposed on the inner wall of the counterweight sleeve 400. A transverse groove with an axial direction perpendicular to the sliding rod 310 is formed on the side wall of the sliding rod 310. The step block 520 is slidably disposed within the transverse groove along its axial direction. One end of the spring 530 is fixed to the bottom of the transverse groove, and the other end is fixed to the large end face of the step block 520. In the initial state, when no oilfield wastewater has submerged the valve plate 320 and no gas has been introduced into the tower body 100, the small end face of the ladder block 520 extends out of the slot of the transverse groove and is located below the protrusion 510 under the elastic force of the spring 530, and its side is in contact with the bottom surface of the protrusion 510.

[0034] When the oilfield wastewater flowing into the tower body 100 submerges the valve plate 320, and the valve plate 320 rises under the pressure of the gas flowing into the tower body 100, the valve plate 320 drives the sliding rod 310 to rise. When the sliding rod 310 rises, the ladder block 520 can provide an upward thrust to the protrusion 510. The thrust provided by the ladder block 520 to the protrusion 510 is affected by the elastic force of the spring 530, and the elastic force of the spring 530 is a constant value. If the counterweight sleeve 400 experiences significant hydraulic pressure and its own weight, the step block 520 will need to overcome a large compressive force with the protrusion 510 when it rises. The thrust provided by the step block 520 to the protrusion 510 (i.e., the force transmitted from the step block 520 to the protrusion 510) will be insufficient to overcome the compressive force between the protrusion 510 and the step block 520. Instead, the greater compressive force will push the step block 520 into the transverse groove, allowing the step block 520 on the sliding rod 310 to break through the protrusion 510, thus... When the counterweight sleeve 400, which has a larger self-weight, remains in place; when the hydraulic pressure and self-weight of the counterweight sleeve 400 are smaller, the squeezing force of the convex part 510 on the ladder block 520 is smaller. At this time, the thrust provided by the ladder block 520 to the convex part 510 can easily overcome the squeezing force between the convex part 510 and the ladder block 520. The ladder block 520, which is pressed against the convex part 510, can push the convex part 510 to rise axially along the sliding rod 310. The convex part 510 can drive the counterweight sleeve 400, which has a smaller self-weight, to rise synchronously.

[0035] A flow guide is installed on the tray 200 to guide the flow of liquid on the tray 200. The flow guide may include an outlet weir 610, an inlet weir 620, and a downcomer 630. Both the outlet weir 610 and the inlet weir 620 are installed on the tray 200 and are located on opposite sides of the central axis of the tray 200. The liquid outflow side of the tray 200 is the side of the tray 200 closest to the outlet weir 610, and the liquid inflow side of the tray 200 is the side of the tray 200 closest to the inlet weir 620. The downcomer 630 is installed at the bottom of the outlet weir 610 and is located above the lower inlet weir 620, with a gap between them.

[0036] In this invention, the outlet weir 610, the inlet weir 620, and the downcomer 630 are all existing technologies and are consistent with the corresponding structures in existing floating valve plate towers. Their specific functions and structures will not be elaborated further here.

[0037] It should be noted that in this invention, the multiple counterweight sleeves 400 are arranged in a certain set level, with the weight gradually increasing. The set level can be set by the user according to the actual situation. For example, there are six counterweight sleeves 400, and the weights of the six counterweight sleeves 400 are set to 5g, 6g, 7g, 8g, 9g, and 10g respectively.

[0038] The operating principle of this invention is as follows: First, oilfield wastewater is introduced into the inlet 103 of the tower body 100 through an external oilfield wastewater supply device. The oilfield wastewater first enters the inlet weir 620 and flows over the inlet weir 620 to the tower plate 200. Then it flows over the outlet weir 610 and flows from the outlet weir 610 into the downcomer 630. The downcomer 630 guides the oilfield wastewater into the inlet weir 620 on the lower tower plate 200. The above process is repeated, and finally an S-shaped flow path is formed in the tower body 100 until the oilfield wastewater is discharged from the outlet 102. The discharged oilfield wastewater is then piped to an external purification device. When the oilfield wastewater enters the inlet weir 620, the inlet weir 620 acts as a buffer to reduce the impact of the oilfield wastewater on the float valve 300, thus making the oilfield wastewater more evenly distributed on the tower plate 200. The outlet weir 610 can maintain a suitable liquid layer thickness on the tower plate 200, so that the liquid layer on the tower plate 200 is sufficient to cover the float valve 300 to form an effective liquid seal. Then, gas is introduced into the air inlet 104 on the tower body 100 through the external gas supply device. The gas can be water vapor. The water vapor passes through the valve hole 210 and pushes the valve plate 320 above the valve hole 210 from the bottom of the tower body 100 to rise, and gradually passes through the upper tower plate 200. After passing through the valve holes 210 on the multiple tower plates 200, it is finally introduced into the external purification device from the exhaust port 101. In this invention, the method of first introducing oilfield wastewater and then introducing gas is consistent with the existing method of introducing liquid and gas in floating valve plate towers, and will not be elaborated further here. When water vapor passes through multiple valve holes 210 on the tray 200, it can push multiple valve plates 320 to rise. Since the liquid level of oilfield wastewater on the tray 200 is different on the inlet side (the side near the inlet weir 620) and the outlet side (the side near the outlet weir 610), the valve plate 320 on the side near the outlet weir 610 experiences a smaller hydraulic pressure, while the valve plate 320 on the side near the inlet weir 620 experiences a larger hydraulic pressure. When the valve plate 320 at the low liquid level rises, the hydraulic pressure on the counterweight sleeve 400 at the corresponding position is relatively small. During the rise of the sliding rod 310, under the compression of the elastic pushing component, most or all of the counterweight sleeves 400 rise synchronously with the sliding rod 310. When the valve plate 320 at the high liquid level rises, the hydraulic pressure on the multiple counterweight sleeves 400 at the corresponding position is relatively large. During the rise of the sliding rod 310, under the compression of the elastic pushing component, most or all of the counterweight sleeves 400 remain in place under their own weight and high hydraulic pressure. The step block 520 on the counterweight sleeve 400 that remains in place can pass over the protrusion 510. When the valve plate 320 at the low liquid level rises and the valve plate 320 at the high liquid level rises, the overall weight formed by the valve plate 320 at the low liquid level and most or all of the counterweight sleeves 400 that are raised is higher than the overall weight formed by the valve plate 320 at the high liquid level and a small portion of the counterweight sleeves 400 that are raised. Because the hydraulic pressure on the valve plate 320 at the low liquid level is less than that on the valve plate 320 at the high liquid level, the airflow can more easily push the valve plate 320 at the low liquid level to rise, and the height it rises is also higher. However, because the overall weight of the valve plate 320 at the low liquid level and most or all of the counterweight sleeves 400 that are lifted is higher than that of the valve plate 320 at the high liquid level and a small portion of the counterweight sleeves 400 that are lifted, the difference between the height the valve plate 320 at the low liquid level and the height the valve plate 320 at the high liquid level rises is smaller. Compared with the existing floating valve plate tower, the difference in the opening degree of the valve plate 320 in the floating valve 300 of the present invention is smaller, which makes the gas outlet of the floating valve 300 on the upper tower plate 200 more uniform when the gas enters the upper tower plate 200, and thus more conducive to maintaining stable operation of gas-liquid mass transfer. When the present invention is no longer performing desulfurization operations on oilfield wastewater, the gas supply is first stopped, and then the oilfield wastewater supply is stopped. After the gas and oilfield wastewater supply to the tower body 100 are stopped, the counterweight sleeve 400, driven by the valve plate 320 through the sliding rod 310, can overcome the limitation of the elastic push component by its own weight and return to its original position, realizing the initialization of the present invention and facilitating the next desulfurization of oilfield wastewater.

[0039] It should be noted that, in this invention, the thrust provided by the gas flow intensity to the tower plate 200 on the valve body must be greater than the sum of the weight of the entire float valve 300 (including the counterweight sleeve 400) and the hydraulic pressure on the entire float valve 300 at the high liquid level, so as to better ensure that the difference in the rising height of the valve plate 320 at the high liquid level and the low liquid level is small, which is more conducive to ensuring the uniformity of the gas output from the float valve 300.

[0040] In some embodiments, the counterweight sleeve 400 includes a sleeve body 410 and a counterweight ring 420. The sleeve body 410 is located inside the perforation and is sleeved on the sliding rod 310. The counterweight ring 420 is sleeved on the sliding rod 310 and fixed to the top of the sleeve body 410. The outer diameter of the counterweight ring 420 is larger than the inner diameter of the perforation, so that the counterweight sleeve 400 hangs on the tower plate 200.

[0041] In this invention, the sleeves 410 inside the multiple counterweight sleeves 400 are completely identical, and the outer diameters of the multiple counterweight rings 420 inside the multiple counterweight sleeves 400 are different. The outer diameters of the multiple counterweight rings 420 gradually increase according to the weight of the set level. The larger the outer diameter of the counterweight ring 420, the greater the weight of the corresponding counterweight sleeve 400. The larger the outer diameter, the greater the hydraulic pressure that the counterweight ring 420 needs to overcome when it is raised.

[0042] In addition, the inner side of the counterweight ring 420 can protrude toward the central axis of the perforation, so that the inner ring of the counterweight ring 420 can act as the protrusion 510 in the elastic push assembly, thereby reducing the number of structural components in this embodiment.

[0043] In some embodiments, a limiting member 330 is provided at the bottom of the valve plate 320. The limiting member 330 can limit the range of movement of the valve plate 320 in the direction parallel to the central axis of the valve hole 210. The specific range can be 2.5-8.5mm. At the same time, the limiting member 330 can also keep the valve plate 320 and the valve hole 210 coaxially arranged.

[0044] The limiting component 330 includes a valve leg 331 and a guide block 332. The valve leg 331 can be a rod-shaped structure fixed to the bottom of the valve plate 320 with its length parallel to the central axis of the valve hole 210. The valve leg 331 is inserted into the valve hole 210 and contacts the hole wall. A limiting groove 211 corresponding to the valve leg 331 is formed on the hole wall of the valve hole 210. The limiting groove 211 can be a straight groove with a certain length and its length direction parallel to the central axis of the valve hole 210. The guide block 332 can be a block-shaped structure fixed to the side of the valve leg 331 facing the corresponding limiting groove 211. The guide block 332 is adapted to the limiting groove 211. The end of the guide block 332 away from the valve leg 331 is inserted into the limiting groove 211. When the valve plate 320 is raised, the guide block 332 can slide along the limiting groove 211. The limiting groove 211 restricts the sliding range of the guide block 332, thereby limiting the sliding space of the valve plate 320 above the tower plate 200.

[0045] In this embodiment, in the initial position, the valve plate 320 is located above the valve hole 210 and can cover the valve hole 210. The guide block 332 is located at the bottom end of the limiting slide groove 211 and elastically pushes the step block 520 in the assembly against the bottom surface of the protrusion 510.

[0046] The limiting member 330 ensures that the valve plate 320 is initially positioned above the valve hole 210 (tower plate 200). This guarantees that after gas is introduced into the tower body 100, the gas can pass through the valve hole 210 and flow through the gap between the valve plate 320 and the tower plate 200 to the top of the tower plate 200. This prevents the gas from being unable to push the valve plate 320 up due to insufficient airflow intensity, thus preventing it from passing through the valve hole 210. Simultaneously, the limiting member 330 also restricts the upward range of the valve plate 320, preventing the valve plate 320 from detaching from the float valve 300 due to excessive airflow intensity, which could cause the valve plate 320 to collide with and damage the tower plate 200.

[0047] In some embodiments, the float valve 300 further includes a cleaning element disposed on the valve plate 320. The cleaning element is configured to clean the valve plate 320 when airflow passes through the valve orifice 210 and pushes the valve plate 320 upward. The cleaning element also has a dead zone mitigation structure that reduces the liquid mass transfer dead zone above the valve plate 320 when the cleaning element cleans the valve plate 320.

[0048] Specifically, the cleaning component may include a first scraper 340, a support rod 350, and a second scraper 360. The first scraper 340, support rod 350, and second scraper 360, like the sliding rod 310, are provided in multiple units. In this embodiment, the valve plate 320 is coaxially disposed above the valve hole 210, and the sliding rod 310 is not directly connected to the valve plate 320 (e.g., Figure 6(As shown), instead, one end of multiple sliding rods 310 located above the tower plate 200 is fixedly connected to multiple first scraper rods 340 respectively.

[0049] The first scraper 340 can be a long rod adapted to the top surface of the valve plate 320, that is, the length direction of the first scraper 340 is parallel to the radial direction of the valve plate 320. The ends of multiple first scrapers 340 away from their corresponding sliding rods 310 are connected to the same first center point, and the first center point is coaxial with the central axis of the valve hole 210. Multiple first scrapers 340 are evenly arranged above the valve plate 320 and form a mesh-like structure covering the valve plate 320, with the first scrapers 340 in contact with the outer top surface of the valve plate 320. A dead zone mitigation structure is provided on the first scraper 340. When the first scraper 340 cleans the outer top surface of the valve plate 320, the dead zone mitigation structure can reduce the gas-liquid mass transfer dead zone on the top surface of the valve plate 320.

[0050] Multiple support rods 350 are inserted into the valve hole 210, and all support rods 350 are parallel to the central axis of the valve hole 210. Each support rod 350 corresponds to one sliding rod 310. The bottom end of the sliding rod 310 extends below the sleeve 410. An elastic connecting piece 370 is provided between the end of the support rod 350 below the valve hole 210 and the bottom end of the corresponding sliding rod 310. The end of the support rod 350 above the valve hole 210 is connected to the second scraper 360.

[0051] Multiple second scraper rods 360 correspond to multiple support rods 350. The length direction of the second scraper rods 360 is parallel to the length direction of the first scraper rods 340, and the ends of the multiple second scraper rods 360 away from their corresponding support rods 350 are all connected to the same second center point, which is coaxial with the central axis of the valve hole 210. The multiple second scraper rods 360 can also form a mesh-like structure, thereby forming a cone-shaped gap cavity between the mesh structure formed by the multiple first scraper rods 340 and the mesh structure formed by the multiple second scraper rods 360, and the valve plate 320 is placed in the gap cavity.

[0052] The elastic connecting piece 370 between the support rod 350 and the sliding rod 310 can be a strip-shaped spring piece. The elastic connecting piece 370 is configured to cause the first scraper 340 and the corresponding second scraper 360 to tend to move closer to each other. This causes the first scraper 340 to contact the outer top surface of the valve plate 320, and the second scraper 360 to contact the inner bottom surface of the valve plate 320.

[0053] In this embodiment, multiple limiting grooves 211 can be provided, and multiple valve legs 331 are also provided. The multiple valve legs 331 are evenly distributed around the central axis of the valve hole 210 on the inner bottom surface of the valve plate 320. The limiting grooves 211 are spiral grooves, and multiple spiral grooves are evenly distributed around the circumference of the valve hole 210, and the multiple spiral grooves do not interfere with each other. The multiple spiral grooves correspond to the multiple valve legs 331 respectively, and the guide blocks 332 on the valve legs 331 are inserted into the corresponding spiral grooves of the valve legs 331.

[0054] In this embodiment, when the valve plate 320 is lifted by the airflow, the guide block 332 can slide along the spiral groove, thereby causing the valve leg 331 to drive the valve plate 320 to rotate. When the valve plate 320 rotates, since neither the first scraper 340 nor the second scraper 360 can rotate, relative motion can be formed between them. When the first scraper 340 rotates relative to the valve plate 320, it can scrape off the impurities (including sulfate deposits) deposited on the outer top surface of the valve plate 320, thus cleaning the outer top surface of the valve plate 320. When the second scraper 360 rotates relative to the valve plate 320, it can scrape off the sulfur deposits, oil deposits, and biological deposits attached to the inner bottom surface of the valve plate 320, thus cleaning the inner bottom surface of the valve plate 320.

[0055] In this embodiment, the arrangement of the first scraper 340 and the second scraper 360 allows the valve plate 320 to be used for a longer period of time, thereby reducing the cost of frequent cleaning of the valve plate 320 and reducing the treatment cost of oilfield wastewater treatment according to the present invention. Simultaneously, the first scraper 340 and the second scraper 360 remove impurities from the valve plate 320, which also reduces the impact of impurities on the weight of the valve plate 320, preventing the opening degree of the valve plate 320 from being affected by impurities.

[0056] In some embodiments, the dead zone mitigation structure includes a flow channel 341 and an air hole 342. The flow channel 341 is formed at the bottom of the first scraper 340. One end of the flow channel 341 extends to the sliding rod 310 and leads to the outside of the valve plate 320, while the other end communicates with the flow channels 341 on other first scrapers 340. The air hole 342 is formed at the bottom of the flow channel 341.

[0057] The length direction of the guide groove 341 is parallel to the length direction of the first scraper 340. Multiple air holes 342 are provided at the bottom of the guide groove 341. The multiple air holes 342 are evenly distributed at the bottom of the guide groove 341 along the length direction of the guide groove 341.

[0058] In this embodiment, when the gas enters the area above the tower plate 200 through the valve hole 210, due to the arrangement of the guide groove 341, some of the gas can enter the guide groove 341 and flow out through the air hole 342 on the guide groove 341. This allows the first scraper 340 covering the valve plate 320 to generate bubbles, and also allows bubbles to be generated in the corresponding area directly above the valve plate 320. This improves the uniformity of gas distribution in the liquid on the tower plate 200, avoids the formation of a gas-liquid mass transfer dead zone directly above the valve plate 320 due to the lack of bubble generation, improves the gas-liquid contact efficiency in this invention, and thus improves the desulfurization efficiency of this invention.

[0059] In addition, the airflow can improve the cleaning efficiency of the first scraper 340 on the outer top surface of the valve plate 320 when it flows in the guide groove 341. The flowing gas can blow away the impurities scraped by the first scraper 340, reducing the residue of impurities on the valve plate 320.

[0060] In some embodiments, the valve plate 320 may be a spherical plate, and the first scraper 340 and the second scraper 360 are arc-shaped rods adapted to the outer top surface and inner top surface of the valve plate 320.

[0061] The spherical panel has a symmetrical curved surface structure, which allows gas to diffuse smoothly along the spherical surface when it flows out of the valve hole 210, forming a more uniform annular airflow, reducing local impact on the liquid layer, reducing mist entrainment, and having excellent stress dispersion ability. It can effectively resist medium pressure fluctuations and mechanical vibrations, and is not easily deformed or fatigued.

[0062] The desulfurization and corrosion prevention treatment process for oilfield produced wastewater provided in this embodiment of the invention is applied to the aforementioned desulfurization and corrosion prevention treatment system for oilfield produced wastewater.

[0063] The desulfurization and corrosion prevention treatment process for oilfield produced wastewater, applied to the aforementioned oilfield produced wastewater desulfurization and corrosion prevention treatment system, includes the following steps: Step 1: The air inlet 104 is connected to an external air supply device through a pipeline, the liquid inlet 103 is connected to an external oilfield wastewater supply source through a pipeline, and the exhaust outlet 101 and the liquid outlet 102 are connected to an external purification device through pipelines. Step 2: The oilfield wastewater entering the tower body 100 from the inlet 103 enters the inlet weir 620, then overflows from the inlet weir 620 and flows to the tower plate 200. When the liquid level of the oilfield wastewater near the outlet weir 610 exceeds the outlet weir 610, the oilfield wastewater flows through the outlet weir 610 to the downcomer 630 and enters the inlet weir 620 of the lower tower plate 200. The above process is repeated until it is discharged from the outlet 102. Step 3: Steam entering the tower body 100 from the inlet 104 passes through the valve holes 210 on the multi-layer tower plates 200 in sequence from the bottom tower plate 200 until it enters the exhaust port 101. When the steam passes through the valve holes 210, it exerts a thrust on the valve plate 320.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A desulfurization and corrosion prevention treatment system for oilfield produced wastewater, characterized in that, include: The tower body has an exhaust port and a liquid drain port at the top and bottom, respectively. The tower body sidewall has a liquid inlet and an air inlet, with the liquid inlet near the top of the tower body and the air inlet near the bottom of the tower body. The tower has multiple trays, which are evenly arranged inside the tower body. Each tray has multiple evenly distributed valve holes. The floating valve, corresponding to the valve orifice, includes a sliding rod and a valve plate. Multiple sliding rods are provided, and the multiple sliding rods are evenly arranged on the valve plate around the circumference of the valve orifice. The sliding rods pass through the tower plate in a direction parallel to the central axis of the valve orifice, and the valve plate is located above the valve orifice. The counterweight sleeve is slidably mounted on the tower plate and sleeved on the sliding rod. Multiple counterweight sleeves are arranged in a set level with progressively increasing weight. The counterweight sleeves are configured to be able to detach from the top of the tower plate. An elastic pushing component is disposed between a sliding rod and a counterweight sleeve. It is configured to drive part or all of the counterweight sleeve to rise when the sliding rod rises. The elastic pushing component includes a protrusion, a step block, and a spring. The protrusion is disposed on the inner wall of the counterweight sleeve. A transverse groove is provided on the side wall of the sliding rod. The step block is slidably disposed in the transverse groove. The spring is disposed between the transverse groove and the step block. The spring is configured to cause the small end face of the step block to extend out of the transverse groove opening. The small end face of the step block is located below the protrusion, and the side of the step block contacts the protrusion. A flow guide, installed on a tray, is used to guide the flow of liquid on the tray.

2. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 1, characterized in that: The counterweight sleeve includes a sleeve body and a counterweight ring. The sleeve body is sleeved on the sliding rod, and the counterweight ring is sleeved on the sliding rod and fixed to the top of the sleeve body. The radius of the counterweight ring is larger than the radius of the hole in the sleeve body. The outer diameter of the counterweight rings on multiple counterweight sleeves is different, and the weight of the multiple counterweight rings gradually increases according to the set weight level.

3. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 1, characterized in that: The valve plate is provided with a limiting member at its bottom. The limiting member is configured to restrict the range of movement of the valve plate in a direction parallel to the central axis of the valve hole, and to keep the valve plate and the valve hole coaxial.

4. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 3, characterized in that: The limiting component includes a valve leg and a guide block. The valve leg is fixed to the bottom of the valve plate. A limiting groove is formed on the wall of the valve hole. The valve leg corresponds to the limiting groove. The guide block is fixed on the side of the valve leg facing the wall of the valve hole. The side of the guide block away from the valve leg is inserted into the corresponding limiting groove.

5. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 4, characterized in that: The float valve also includes a cleaning element disposed on the valve plate and configured to clean the valve plate when the airflow pushes the valve plate up. The cleaning element has a dead zone relief structure, which reduces the gas-liquid mass transfer dead zone above the valve plate when the cleaning element cleans the valve plate.

6. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 5, characterized in that: The cleaning component includes a first scraper, a support rod, and a second scraper. The first scraper is fixed to one end of the sliding rod that protrudes from the tower plate. The ends of multiple first scrapers that are away from their corresponding sliding rods are connected to the same first center point. The dead zone relief structure is provided on the first scraper. The support rod passes through the valve hole, and the second scraper is connected to the end of the support rod that extends out of the valve hole. There are multiple support rods and multiple second scrapers. The multiple support rods and multiple second scrapers are evenly distributed along the circumference of the valve hole. The ends of the multiple second scrapers that are away from the corresponding support rods are connected to the same second center point. Multiple support rods correspond one-to-one with multiple sliding rods and are all parallel to the central axis of the valve hole. Multiple first scraper rods and multiple second scraper rods correspond one-to-one and are parallel to each other. The first scraper rods and their corresponding second scraper rods are spaced apart. The valve plate is clamped in the gap cavity formed by the multiple first scraper rods and multiple second scraper rods. An elastic connecting piece is provided between the support rods and their corresponding sliding rods. The elastic connecting piece is configured to make the second scraper rods and the first scraper rods tend to move closer to each other, so that the first scraper rods abut against the outer top surface of the valve plate and the second scraper rods abut against the inner bottom surface of the valve plate. The limiting slide groove is provided with multiple grooves, and the valve leg is provided with multiple valve legs. The multiple valve legs are evenly distributed around the central axis of the valve hole on the inner bottom surface of the valve plate. The limiting slide groove is a spiral groove, and multiple spiral grooves are evenly distributed along the circumference of the valve hole. The spiral grooves do not interfere with each other. The multiple spiral grooves correspond to the multiple valve legs respectively. The guide block is inserted into the spiral groove corresponding to the valve leg.

7. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 6, characterized in that: The dead zone relief structure includes a guide groove and an air hole. The guide groove is opened at the bottom of the first scraper. One end of the guide groove extends to the sliding rod and leads to the outside of the valve plate, and the other end communicates with the guide grooves on other first scrapers. The air hole is opened at the bottom of the guide groove.

8. The desulfurization and corrosion prevention treatment system for oilfield produced wastewater according to claim 6, characterized in that: The valve plate is a spherical panel, and the first scraper and the second scraper are arc-shaped rods adapted to the outer top surface and inner top surface of the valve plate.

9. A desulfurization and corrosion prevention treatment process for oilfield produced wastewater, applied to the desulfurization and corrosion prevention treatment system for oilfield produced wastewater as described in any one of claims 1-8, characterized in that, Includes the following steps: Step 1: The air inlet is connected to an external air supply device through a pipe, the liquid inlet is connected to an external oilfield wastewater supply source through a pipe, and the exhaust port and the liquid outlet are connected to an external purification device through pipes; Step 2: The oilfield wastewater entering the tower body from the inlet enters the inlet weir, then overflows from the inlet weir and flows to the tower plate. When the liquid level of the oilfield wastewater near the outlet weir is above the outlet weir, the oilfield wastewater flows through the outlet weir to the downcomer and enters the inlet weir of the lower tower plate. The above process is repeated until it is discharged from the outlet. Step 3: The steam entering the tower body from the inlet passes through the valve holes on the multi-layer tower plates in sequence from the bottom tower plate until it enters the exhaust port. When the steam passes through the valve holes, it exerts a thrust on the valve plate.

Images