Oil-water separation

Abstract

A system includes a vessel, a module, and a skimming trough. The vessel includes a feed inlet distributor. The feed inlet distributor includes an inlet pipe, a housing, and a plurality of vanes disposed within the housing. The inlet pipe is configured to receive a feed stream including oil and water. The housing defines a plurality of perforations. The vanes are configured to direct flow of the feed stream through the perforations out of the housing. The module is disposed within the vessel downstream of the feed inlet distributor. The module includes a plurality of coalescer plates and a set of baffle plates disposed within the vessel downstream of the coalescer plates. The set of baffle plates includes a first underflow baffle plate, an overflow baffle plate, and a second underflow baffle plate. The second underflow baffle plate defines a plurality of perforations. The skimming trough spans the vessel longitudinally.

Description

[0001] Priority Statement

[0002] This application claims priority to U.S. Patent Application No. 16 / 912,429, filed June 25, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to phase separation, particularly oil-water separation. Background Technology

[0004] Oil and gas production processes may generate substantial amounts of water as a byproduct. This produced water is treated so that it can be safely discharged into water bodies or reinjected into storage facilities, for example. Produced water treatment can include various processes to separate unwanted substances from the produced water. Some examples include oil removal, total dissolved solids removal, and softening. Summary of the Invention

[0005] Certain aspects of the subject matter can be implemented as an oil-water separation system. The system includes a vessel, a module, and an oil skimmer. The vessel includes a feed inlet distributor. The feed inlet distributor includes an inlet pipe, a housing, and multiple blades arranged within the housing. The inlet pipe is configured to receive a feed flow. The feed flow includes oil and water. The outlet of the inlet pipe is connected to the housing. The cross-sectional area of ​​the housing is larger than the cross-sectional area of ​​the inlet pipe relative to the flow of the feed flow. The larger cross-sectional area of ​​the housing is configured to slow the flow of the feed flow, thereby facilitating the separation of the oil and water. The housing defines multiple perforations. These blades are configured to guide the flow of the feed flow through these perforations and out of the housing. The module is arranged within the vessel, downstream of the feed inlet distributor. The module includes multiple coalescing plates. These coalescing plates are configured to facilitate the coalescence of the oil. The module includes a set of baffles. The set of baffles includes a first underflow baffle, a second underflow baffle, and an overflow baffle, the overflow baffle being disposed between the first and second underflow baffles. The first underflow baffle is configured to guide flow below it. The overflow baffle is configured to be submerged below the liquid level in the vessel and guide fluid flow above it. The second underflow baffle is downstream of the first underflow baffle and defines a plurality of perforations. The second underflow baffle is configured to guide fluid flow below it and through the perforations. An oil skimmer is disposed within the vessel. The oil skimmer extends longitudinally across the vessel and slopes downward relative to gravity toward the inner surface of the vessel. The oil skimmer is configured to skim oil from the oil-water interface layer formed within the vessel.

[0006] This aspect and other aspects may include one or more of the following features.

[0007] In some embodiments, the module includes a porous or perforated wall disposed within the vessel, between the feed inlet dispenser and the coalescing plates.

[0008] In some embodiments, the system includes multiple modules. In some embodiments, each of these modules is longitudinally spaced apart from the others within the vessel.

[0009] In some implementations, each of these coalescing plates is parallel to each other and tilted upwards relative to gravity.

[0010] In some embodiments, one or more of the first underflow baffle, the second underflow baffle, or the overflow baffle include rounded ends.

[0011] In some embodiments, the distance between the first underflow baffle and the overflow baffle and the distance between the overflow baffle and the second underflow baffle are substantially the same.

[0012] In some embodiments, the system includes a plurality of guide vanes arranged between the first underflow baffle and the second underflow baffle and above the overflow baffle relative to gravity. In some embodiments, these guide vanes are configured to be submerged below the liquid level within the vessel.

[0013] In some implementations, these guide vanes extend from the overflow baffle to the second underflow baffle.

[0014] In some implementations, these guide vanes extend from the first underflow baffle to the second underflow baffle.

[0015] In some embodiments, the outlet of the inlet pipe is connected to the lower portion of the housing of the feed inlet distributor. In some embodiments, the perforations defined by the housing of the feed inlet distributor are on the upper portion of the housing of the feed inlet distributor.

[0016] In some embodiments, the scraper groove extends longitudinally across the vessel over the area covering the housing of the feed inlet dispenser, the first module, and the second module.

[0017] In some embodiments, the module includes a porous or perforated wall immediately upstream of these coalescing plates. In some embodiments, the module is a first module. In some embodiments, the system includes a second module disposed within the vessel, downstream of the first module. In some embodiments, the second module is substantially identical to the first module. In some embodiments, the skimmer longitudinally spans the vessel over the area covering the housing of the feed inlet dispenser, the first module, and the second module.

[0018] In some embodiments, the housing of the feed inlet dispenser is configured to be submerged below the liquid level within the vessel.

[0019] In some embodiments, these coalescing plates are corrugated. In some embodiments, for each of these coalescing plates, the contact angle between the oil droplet and the surface of the corresponding coalescing plate is greater than 90 degrees.

[0020] Certain aspects of the subject matter can be implemented as a method. A feed stream comprising oil and water is received through an inlet pipe. This feed stream is discharged from the outlet of the inlet pipe into a housing. The cross-sectional area of ​​the housing is larger than that of the inlet pipe relative to the direction of fluid flow. The housing is arranged within a vessel. The feed stream is guided by multiple blades arranged within the housing through multiple perforations defined by the housing and exits the housing. A module is arranged within the vessel, downstream of the housing. Oil droplets are coalesced by multiple coalescing plates of the module. The coalesced oil droplets are guided by these coalescing plates in an upward tilting direction opposite to gravity. The module includes a set of baffles arranged within the vessel, downstream of these coalescing plates. This set of baffles includes a first underflow baffle, an overflow baffle, and a second underflow baffle. Fluid flow is directed below the first underflow baffle. Fluid flow is directed above the overflow baffle. The overflow baffle is downstream of the first underflow baffle. Fluid flow is directed below the second underflow baffle. The second underflow baffle is downstream of the overflow baffle. The coalesced oil droplets are guided towards the inner surface of the vessel by an oil skimmer. The oil skimmer is arranged inside the vessel and extends longitudinally across it. The oil skimmer slopes downwards relative to gravity towards the inner surface of the vessel. Water is drained from the vessel.

[0021] This aspect and other aspects may include one or more of the following features.

[0022] In some implementations, the feed stream comprises up to about 10% by volume of oil.

[0023] In some embodiments, the oil concentration of the water discharged from the vessel is less than 50 parts by weight per million parts by weight.

[0024] In some embodiments, coalescing these oil droplets includes receiving the oil droplets through these coalescing plates, and the oil droplets coalescing together as they pass through these coalescing plates.

[0025] Details of one or more embodiments of the subject matter disclosed herein are set forth in the accompanying drawings and description. Other features, aspects, and advantages of the subject matter will become apparent from the description, drawings, and claims. Attached Figure Description

[0026] Figure 1A This is a schematic diagram of an example phase separator.

[0027] Figure 1B This is a schematic diagram of an example phase separator, which includes a representation of fluid flow through the phase separator.

[0028] Figure 2A It is possible Figure 1A An example of implementation in a phase separator is given by a side view of the feed inlet distributor.

[0029] Figure 2B yes Figure 2A A front view of the feed inlet distributor.

[0030] Figure 3A It is possible Figure 1A A cross-sectional view of an example set of coalescing plates implemented in a phase separator.

[0031] Figure 3B It is possible Figure 1A A cross-sectional view of an example set of coalescing plates implemented in a phase separator.

[0032] Figure 3C It is possible Figure 1A A cross-sectional view of an example set of coalescing plates implemented in a phase separator.

[0033] Figure 3D This is a schematic diagram of an example configuration of multiple coalescing plates.

[0034] Figure 3E This is a schematic diagram of an example oil droplet on a coalescing plate.

[0035] Figure 4A It is possible Figure 1A A schematic diagram of an example set of baffles implemented in a phase separator.

[0036] Figure 4B It is possible Figure 1A A schematic diagram of an example set of baffles implemented in a phase separator.

[0037] Figure 4C It is possible Figure 1A A schematic diagram of an example set of baffles implemented in a phase separator.

[0038] Figure 4D It is possible Figure 1A A schematic diagram of an example set of baffles implemented in a phase separator.

[0039] Figure 4E It is possible Figure 1A A schematic diagram of an example set of baffles implemented in a phase separator.

[0040] Figure 5A It is possible Figure 1A A cross-sectional view of an example oil skimmer implemented in a phase separator.

[0041] Figure 5B It is possible Figure 1A A cross-sectional view of an example oil skimmer implemented in a phase separator.

[0042] Figure 6A This is a schematic diagram of an example phase separator.

[0043] Figure 6B This is a schematic diagram of an example phase separator.

[0044] Figure 6C This is a schematic diagram of an example phase separator.

[0045] Figure 7A It means Figure 1A A flowchart illustrating the process and function of a phase separator.

[0046] Figure 7B This is a flowchart of an example method for phase separation. Detailed Implementation

[0047] This disclosure describes oil-water separation. Specifically, it describes the separation of oil and water in an oily water stream, where the oil phase is dispersed within a large volume of water. Oil-water separation includes fluid flow rate reduction, flow regulation, droplet coalescence, and oil separation and collection. The subject matter described in this disclosure can be implemented in specific embodiments to achieve one or more of the following advantages: Processing capacity and effluent yield can be increased while maintaining stable oil removal compared to conventional separators. Modular components of fluid dynamic control elements for functions such as rate reduction, flow distribution, oil coalescence, oil separation / scraping, surge protection control, and level control contribute to increased capacity. The described concepts can be implemented as retrofit options for existing separator vessels, increasing their capacity by more than 50% and reducing the oil concentration in treated water to 50 parts by weight per million parts by weight (ppm). The described concepts can be implemented in new oil-water separator vessels. The oil-water separator includes multiple modules that facilitate oil-water separation. Large-scale recirculation in the oil-water separator can be mitigated. The streamlines (general direction of fluid flow) are primarily parallel to the longitudinal axis of the oil-water separator. Compared to conventional separators, the top-down rotating and downward flow patterns within the oil-water separator are reduced. The advantages mentioned above also allow for an increased oil skimming rate within the oil-water separator. The residence time distribution in the oil-water separator is narrower compared to conventional separators. Guide vanes located between the baffles reduce lateral fluid flow near the oil-water interface and also distribute the fluid flow longitudinally across the vessel. The longitudinal skimming channels absorb flow surges that may be caused by rapid inlet feed fluctuations, thereby mitigating the negative impacts on oil skimming and removal.

[0048] Figure 1A This is a schematic diagram of an oil-water separation system 100. The oil-water separation system 100 includes a vessel 101. The vessel 101 includes a feed inlet distributor 102. The feed inlet distributor 102 includes an inlet pipe 103 and a housing 104. The oil-water separation system 100 includes a module 150 and an oil skimmer 110, each of which is arranged within the vessel 101. The module 150 is arranged within the vessel 101, downstream of the feed inlet distributor 102, and includes a plurality of coalescing plates and a set of baffles 107. The set of baffles 107 is arranged within the vessel 101, downstream of the coalescing plates 105, and includes a first underflow baffle 107a, a second underflow baffle 107b, and an overflow baffle 107c. The coalescing plates 105 are configured to coalesce oil droplets together, and the set of baffles 107 is configured to separate fluid flows to facilitate oil-water separation. Despite Figure 1AThe diagram shows a single module 150, but the oil-water separation system 100 may include additional modules 150, such as two, three, or more than three modules 150. The modularity of the oil-water separation system 100 facilitates staged oil removal. In some embodiments, module 150 includes a porous or perforated wall 151 located immediately upstream of the coalescer plate 105. The porous or perforated wall 151 will be described in more detail later.

[0049] Figure 1B This is a schematic diagram of an oil-water separation system 100, including a representation of fluid flow through the system. The velocity reduction and flow regulation section of the oil-water separation system 100 includes a feed inlet distributor 102. The droplet coalescence section of the system includes a coalescer plate 105. The oil separation and collection section of the system includes a baffle 107 and an oil skimmer 110.

[0050] A feed stream comprising oil and water flows to the oil-water separation system 100. In some embodiments, the feed stream comprises up to about 10 volume percent (vol.%) of oil. An inlet pipe 103 is configured to receive the feed stream. The outlet of the inlet pipe 103 is coupled to a housing 104. The feed stream flows through the inlet pipe 103 into the housing 104. A feed inlet distributor 102 is configured to distribute the flow of the feed stream to facilitate the separation of oil and water. In cases where the feed stream comprises solid material, the solid material may fall out from the bottom of the housing 104 and then be stored (e.g., stored in a solid container) or disposed of.

[0051] The feed stream exits the housing 104 and flows through a porous or perforated plate to reach module 150. Coalescing plate 150 is configured to promote oil coalescence. For example, oil may exist in the feed stream as oil droplets dispersed in a large volume of aqueous phase. Coalescing plate 105 promotes the coalescence of these oil droplets. Due to gravity, lighter fluids (e.g., oil) tend to rise relative to denser fluids (e.g., water). Therefore, coalesced oil droplets tend to rise relative to water within the vessel. Typically, as fluid flows within vessel 101, oil tends to rise relative to water, and oil accumulates in the upper fluid layer within vessel 101. Coalescing plate 105 will be described in more detail later.

[0052] The fluid then flows from the coalescing plate 105 to the set of baffles 107. A first underflow baffle 107a is configured to direct fluid flow below it. An overflow baffle 107c is disposed between the first underflow baffle 107a and the second underflow baffle 107b. The overflow baffle 107c is configured to direct fluid flow above it. The second underflow baffle 107b is configured to direct fluid flow below it.

[0053] The tortuous flow path created by this set of baffles 107 also facilitates the separation of oil and water. Oil tends to remain upstream of the first underflow baffle 107a because it is less likely to flow below the first underflow baffle 107a compared to water. However, if oil does flow below the first underflow baffle 107a in some way along with water, it tends to remain as an upper layer in a stagnant region downstream of the first underflow baffle 107a and upstream of the second underflow baffle 107b. This set of baffles 107 will be described in more detail later.

[0054] The oil scraper 110 is configured to scrape oil from the oil-water interface layer formed within the vessel 101. As oil accumulates in the upper fluid layer within the vessel 101, the oil scraper 110 scrapes the oil from the upper fluid layer and discharges the oil from the vessel 101. The oil scraper 110 will be described in more detail later.

[0055] In some embodiments, module 150 includes a porous or perforated wall 151 immediately upstream of coalescer plate 105. The porous or perforated wall 151 includes pores, perforations, slots, mesh, or combinations thereof. The porous or perforated wall 151 can facilitate oil and water separation. For example, the porous or perforated wall 151 can slow the flow rate of fluid within vessel 101, which facilitates oil and water separation. In some embodiments, oil-water separation system 100 includes additional porous or perforated walls 151 that can be arranged between two components of the oil-water separation system 100. For example, additional porous or perforated walls 151 can be arranged between coalescer plate 105 and the set of baffles 107. In some embodiments, module 150 includes two porous or perforated walls 151 arranged immediately upstream of coalescer plate 105. In such an implementation, the open flow areas of the two porous or perforated walls 151 can be different from each other. For example, the first porous or perforated wall 151 may have a larger open flow area, larger perforations, or both compared to the second porous or perforated wall 151.

[0056] Figure 2AThis is a side view of the feed inlet distributor 102. The feed inlet distributor 102 includes a plurality of blades 104a arranged within a housing 104. The housing 104 defines a plurality of perforations 104b. The blades 104a are configured to guide the flow of the feed stream through the perforations 104b and out of the housing 104. In some embodiments, the blades 104a are vertical blades. In some embodiments, the blades 104a are deviated from the vertical direction (i.e., are angled). In some embodiments, some blades 104a are vertical blades, while some blades 104a are angled. The blades 104a prevent the flow from rotating (turbulent) and guide the fluid flow in a generally upward direction toward the perforations 104b. Figure 2B As shown, perforations 104b are located in the upper portion of the housing 102 relative to gravity. Flow through perforations 104b facilitates the separation of oil and water in the feed stream. In some embodiments, the diameter of perforations 104b ranges from about 5 mm to about 60 mm. The diameter of perforations 104b may be uniform, or the diameters of these perforations may be different. In some embodiments, the total open flow area of ​​perforations 104b relative to the general flow direction ranges from about 10% to about 50% of the cross-sectional area of ​​the housing 104. The feed inlet distributor 102 is configured to be completely submerged below the liquid level within the vessel 101.

[0057] Figure 2B This is a front view of the feed inlet distributor 102. The cross-sectional area of ​​the housing 104 is larger than that of the inlet pipe 103 relative to the feed flow. In some embodiments, the cross-sectional area of ​​the housing 104 is at least twice the cross-sectional area of ​​the inlet pipe 103. The larger cross-sectional area of ​​the housing 104 is configured to slow the flow of the feed flow, thereby facilitating the separation of oil and water. In some embodiments, the housing 104 defines a plurality of perforations 104c located in the lower portion of the housing 102 relative to gravity. In some embodiments, the diameter of the perforations 104c ranges from about 1 mm to about 10 mm. The diameter of the perforations 104c can be uniform, or the diameters of the perforations can be different. These perforations 104c allow solid material that may be entrained in the feed flow to fall through these perforations 104c rather than accumulate within the housing 104. In such embodiments, the outlet of the perforation 104c can be coupled to a solid container or a discharge port. Figure 1A and Figure 1B An example is shown in the image.

[0058] Figure 3A This is a cross-sectional view of an embodiment of a coalescing plate 105 arranged within a vessel 101. In some embodiments, such as Figure 3AAs shown, the coalescer plates 105 are mirror images of the centerline of the vessel 101. In some embodiments, the coalescer plates 105 are parallel to each other. The coalescer plates 105 may be angled relative to the centerline. For example, the coalescer plates 105 may be tilted upward relative to gravity in the direction of fluid flow within the vessel 101. In some embodiments, the angle (θ) between each coalescer plate and the centerline is in the range of about 30 degrees (°) to about 60 degrees. For example, the angle (θ) between each coalescer plate and the centerline is 45 degrees. In some embodiments, the vertical spacing between adjacent coalescer plates is the same for all coalescer plates 105. The vertical spacing between adjacent coalescer plates may be selected based on various parameters for coalescence, such as the target droplet size range. In some embodiments, the vertical spacing between adjacent coalescer plates is different among the coalescer plates 105. For example, starting from the bottommost coalescer plate, the vertical spacing between adjacent coalescer plates gradually decreases with each successive coalescer plate. For example, starting with the bottom coalescer plate, the vertical spacing between adjacent coalescer plates gradually increases with each successive coalescer plate.

[0059] The pressure drop of the fluid flowing across coalescer plate 105 is inversely proportional to the distance between adjacent coalescer plates. For example, as the distance between adjacent coalescer plates decreases, the pressure drop across these adjacent coalescer plates increases.

[0060] Figure 3B This is a cross-sectional view of an embodiment of a coalescing plate 105 arranged within a vessel 101. In some embodiments, such as Figure 3B As shown, the coalescer plate 105 comprises a plurality of rectangular units composed of coalescer plates distributed within the vessel 101. Each rectangular unit composed of coalescer plates includes its own set of coalescer plates, which are angled relative to a centerline. In some embodiments, each set of coalescer plates 105 comprises equidistant (i.e., vertically uniformly distributed) coalescer plates. In some embodiments, each set of coalescer plates 105 comprises coalescer plates that differ in their vertical distribution. In some embodiments, the vertical spacing between the coalescer plates 105 is the same across all sets of coalescer plates. In some embodiments, the vertical spacing between the coalescer plates 105 is different across all sets of coalescer plates 105. For example, the first set of coalescing plates 105 may include coalescing plates with a vertical spacing of 20 mm between adjacent coalescing plates, while the second set of coalescing plates 105, positioned above the first set of coalescing plates (within the vessel 101 relative to gravity), may include coalescing plates with a vertical spacing of 40 mm between adjacent coalescing plates. Figure 3A The configurations shown are similar. Figure 3B In the configuration shown, the coalescer plate 105 is mirrored across the center line of the vessel 101. Figure 3C It shows Figure 3B A portion of the embodiment is shown, along with arrows indicating the general direction of fluid (oil) flow through the coalescer plate 105.

[0061] Figure 3D This is a schematic diagram of an example configuration of multiple coalescing plates 105. In some embodiments, each coalescing plate 105 is mounted to a grid plate 106. The grid plate 106 holds each coalescing plate 105 in its individual position and also prevents the upstream flow of oil-water mixture from rising between the coalescing plates 105. The grid plate 106 can prevent water from entering the vertical channels between adjacent coalescing plates 105. For example, relative to the general direction of fluid flow within the vessel 101, the grid plate 106 prevents upstream fluid from interfering with the coalescence of oil droplets between horizontally adjacent coalescing plates 105.

[0062] Figure 3E This is an enlarged schematic diagram of an example oil droplet on a coalescing plate. In some embodiments, the coalescing plate 105 is made of metal (such as stainless steel or duplex stainless steel) or polymer (such as polypropylene). In some embodiments, the coalescing plate 105 is treated or formed of a material that makes the coalescing plate oleophobic and non-stick, such that the contact angle (φ) between the oil droplet and the coalescing plate is greater than 90°. In some embodiments, the contact angle (φ) between the oil droplet and the coalescing plate is greater than 150°. This reduces the contact area between the oil droplet and the coalescing plate, reduces the resistance to the movement of the oil droplet along the surface of the coalescing plate, and reduces the apparent tackiness of the droplets to the surface of the coalescing plate, thereby making cleaning easier during periodic maintenance. In some embodiments, the coalescing plate 105 comprises a flat coalescing plate. In some embodiments, the coalescing plate 105 comprises a corrugated coalescing plate.

[0063] Figure 4AThis is a schematic diagram of an example set of baffles 107. In some embodiments, the spacing between the first underflow baffle 107a and the overflow baffle 107c and the spacing between the overflow baffle 107c and the second underflow baffle 107b are substantially the same. In some embodiments, the second underflow baffle 107b defines perforations. For example, the second underflow baffle 107b may be in the form of a porous or perforated plate or an expanded metal mesh. In some embodiments, the second underflow baffle 107b defines a vertical slot, a horizontal slot, or both. The open flow area of ​​the second underflow baffle 107b (whether or not it is composed of perforations, slots, mesh, or a combination thereof) allows fluid to flow below or through the second underflow baffle 107b. In embodiments where the longitudinal length of the vessel 101 is limited (e.g., in retrofit applications), such an open flow area can be implemented in the second underflow baffle 107b. In some embodiments, the baffles in the set of baffles 107 are made of metal (such as stainless steel or duplex stainless steel) or polymer (such as polypropylene). In some embodiments, the baffles in the set of baffles 107 are treated or formed of a material that makes the set of baffles 107 oleophobic and non-stick, such that the contact angle between the oil droplet and the baffle (107a, 107b or 107c) is greater than 90° (similar to coalescer plate 105).

[0064] In some embodiments, the oil-water separation system 100 includes guide vanes 107d. In some embodiments, such as Figure 4A As shown, guide vanes 107d are arranged between the first underflow baffle 107a and the second underflow baffle 107b and above the overflow baffle 107c. Guide vanes 107d are configured to be submerged below the liquid level within the vessel 101. In some embodiments, guide vanes 107d are submerged below the upper fluid layer composed of oil within the vessel 101. In some embodiments, such as... Figure 4A As shown, the guide vane 107d crosses from the overflow baffle 107c to the second underflow baffle 107b.

[0065] Figure 4B This is a schematic diagram of an example set of baffles 107. Figure 4B The set of baffles 107 shown is... Figure 4A The set of baffles 107 shown is substantially similar. In some embodiments, such as Figure 4B As shown, the guide vane 107d crosses from the first underflow baffle 107a to the second underflow baffle 107b.

[0066] Figure 4C This is a schematic diagram of an example set of baffles 107. Figure 4C The set of baffles 107 shown is... Figure 4A The set of baffles 107 shown is substantially similar. In some embodiments, such as Figure 4C As shown, the overflow baffle 107c includes an angled end. In some embodiments, the angle (Φ) of the angled end of the overflow baffle 107c from the vertical direction ranges from 0° to 45°. The angled end can increase the cross-sectional area for fluid flow and can also promote a reduction in fluid flow velocity as the fluid flows upward and approaches the liquid surface within the vessel 101. Flow deceleration can promote oil droplet separation and oil skimming. This contrasts with straight baffles (0° from the vertical direction), which can lead to flow separation, wall detachment, eddy current formation, or a combination of these, all of which can disrupt oil droplet separation.

[0067] Figure 4D This is a schematic diagram of an example set of baffles 107. Figure 4D The set of baffles 107 shown is... Figure 4A The set of baffles 107 shown is substantially similar. In some embodiments, such as Figure 4D As shown, the overflow baffle 107c includes a rounded end. The rounded end provides a smooth transition area to mitigate flow separation around the end of the overflow baffle 107c and also facilitates smooth fluid flow to the guide vane 107d.

[0068] Figure 4E This is a schematic diagram of an example set of baffles 107. Figure 4E The set of baffles 107 shown is... Figure 4A The set of baffles 107 shown is substantially similar. In some embodiments, such as Figure 4E As shown, each of the first underflow baffle 107a, the second underflow baffle 107b, and the overflow baffle 107c includes a rounded end. The rounded ends of these baffles 107 can facilitate smooth fluid flow around these baffles 107.

[0069] Figure 5A This is a cross-sectional view of an embodiment of the oil scraper groove 110. (See attached image.) Figure 5AAs shown, the oil-water separation system 100 may include a plurality of skimmed grooves 110, such as two skimmed grooves 110. The skimmed grooves 110 slope downward relative to gravity toward the inner surface of the vessel 101. In some embodiments, each skimmed groove 110 includes curved portions that gradually slope toward the inner surface of the vessel 101. Each skimmed groove 110 may include an outlet near its bottom for discharging oil from the vessel 101. In some embodiments, the outlet discharges to an oil collection reservoir located in the head of the vessel 101. In some cases, some water may exit the vessel 101 along with the oil from the outlet of the skimmed groove 110. In some embodiments, each skimmed groove 110 longitudinally traverses a region within the vessel 101 that covers the housing 104 and module 150 (which includes a coalescer plate 105 and a set of baffles 107) (i.e., overlaps with the housing and module). In some embodiments, the oil scraper 110 is made of metal (such as stainless steel or duplex stainless steel) or polymer (such as polypropylene). Figure 5B This is a cross-sectional view of an embodiment of the oil scraper groove 110. Figure 5B The oil scraper groove 110 and Figure 5A The oil scraper grooves are basically similar, but have different shapes.

[0070] Figure 6A This is a schematic diagram of an implementation of the oil-water separation system 100. Figure 6A The oil-water separation system 100 shown is Figure 1A and Figure 1B The illustrated implementation is substantially similar, but includes copies of some components. For example, Figure 6A The oil-water separation system 100 includes multiple modules 150 (first module 150a and second module 150b). The second module 150b is downstream of the first module 150a. Although in Figure 6A The diagram shows two modules 150, but the oil-water separation system 100 may include additional modules 150, such as three or more modules 150. This also applies to any of the components mentioned above in the oil-water separation system 100. That is, the oil-water separation system 100 may include additional feed inlet distributors(s) 102, additional scraper(s) 110, or both.

[0071] Figure 6B This is a schematic diagram of an implementation of the oil-water separation system 100. Figure 6B The oil-water separation system 100 shown is Figure 6A The embodiments shown are basically similar, but the placement of the various components differs. For example, Figure 6BThe oil-water separation system 100 includes multiple modules 150 (a first module 150a and a second module 150b) arranged on opposite sides of the feed inlet distributor 102. In such an embodiment, the second module 150b is not considered (e.g.) Figure 6A (The situation is the same as in the oil-water separation system 100) downstream of the first module 150a. Instead, it passes through... Figure 6B The general fluid flow in the oil-water separation system 100 generally flows from the middle of the system outwards to both sides. Although in Figure 6B The diagram shows two modules (150a, 150b), but the oil-water separation system 100 may include additional modules 150, such as three or more modules 150. This also applies to any of the components mentioned above in the oil-water separation system 100. That is, the oil-water separation system 100 may include additional feed inlet distributors(s) 102, additional scraper(s) 110, or both.

[0072] Figure 6C This is a schematic diagram of an implementation of the oil-water separation system 100. Figure 6C The oil-water separation system 100 shown is Figure 6B The illustrated implementation is substantially similar, but includes copies of some components. For example, the oil-water separation system 100 may include a third module 150c and a fourth module 150d, the third module being downstream of the first module 150a and the fourth module being downstream of the second module 150b. In such an implementation, approximately half of the fluid entering the oil-water separation system 100 will flow through the first module 150a and then through the third module 150c, while the other half of the fluid entering the oil-water separation system 100 will flow through the second module 150b and then through the fourth module 150d. Although in Figure 6C The diagram shows four modules (150a, 150b, 150c, 150d), but the oil-water separation system 100 may include additional modules 150, such as five or more modules 150. This also applies to any of the components mentioned above in the oil-water separation system 100. That is, the oil-water separation system 100 may include additional feed inlet distributors(s) 102, additional scraper(s) 110, or both.

[0073] Figure 7AThis is a flowchart illustrating the process and function of the oil-water separation system 100. A feed stream comprising oil and water is introduced into the oil-water separation system 100. The feed stream may include, for example, oil droplets dispersed in a large volume of aqueous phase. In some embodiments, the feed stream comprises up to about 10 vol.% oil. The feed stream velocity is reduced, for example, by a feed inlet distributor 102. Oil droplets are coalesced, for example, by a coalescing plate 105. Oil is separated and collected, for example, by a set of baffles 107 and an oil skimmer 110. The collected oil is discharged from the oil-water separation system 100. The oil-water separation system 100 may include a surge compartment for retaining water separated from the feed stream. The surge compartment may be located within the vessel 101, downstream of module 150. In embodiments including multiple modules 150, the surge compartment may be located downstream of the last module 150 relative to the general direction of fluid flow through the vessel 101. Water may be discharged from the oil-water separation system 100. In some embodiments, the oil concentration of the water discharged from the oil-water separation system 100 is less than 100 ppm. In some embodiments, the oil concentration of the water discharged from the oil-water separation system 100 is less than 50 ppm.

[0074] Figure 7B This is a flowchart of an example method 700 for phase separation. Method 700 can be implemented by an oil-water separation system 100. In step 702, a feed flow comprising oil and water is received through the inlet pipe (e.g., inlet pipe 103) of the feed inlet distributor 102.

[0075] In step 704, the feed flow is discharged from the outlet of the inlet pipe 103 into the housing (e.g., housing 104) of the feed inlet distributor 102. As previously mentioned, the housing 104 is arranged inside the vessel 101 and has a larger cross-sectional area than the inlet pipe 103 relative to the direction of fluid flow.

[0076] In step 706, the feed flow is guided by a blade (blade 104a) through a perforation (e.g., perforation 104b) defined by the housing 104 and exits the housing 104. As previously mentioned, blade 104a is arranged within the housing 104.

[0077] In step 708, oil droplets are coalesced by a coalescing plate (e.g., coalescing plate 105) disposed within the vessel 101 and downstream of the housing 104. The coalescing plate 105 receives the oil droplets, and the droplets coalesce together as they pass over the surface of the coalescing plate 105.

[0078] In step 710, the coalesced oil droplets are guided in an upward tilting direction opposite to gravity. Step 710 can be performed by the coalescing plate of the first module 105.

[0079] In step 712, the fluid flow is directed to a baffle (e.g., a first underflow baffle 107a) arranged inside the vessel 101, downstream of the coalescer plate 105.

[0080] In step 714, fluid flow is directed to a baffle (e.g., overflow baffle 107c) disposed within the vessel 101, downstream of the first underflow baffle 107a.

[0081] In step 716, fluid flow is directed to a baffle (e.g., a second underflow baffle 107b) disposed within vessel 101, downstream of overflow baffle 107c. In some embodiments, such as those where the second underflow baffle 107b has an open flow area (e.g., perforations, slots, or both), a portion of the fluid flow is directed through the second underflow baffle 107b.

[0082] In some implementations, steps 708, 710, 712, 714, and 716 are repeated based on the number of modules 150 present within the oil-water separation system 100. For example, steps 708, 710, 712, 714, and 716 are repeated for each additional module 150 present within the oil-water separation system 100. Each progression of steps 708, 710, 712, 714, and 716 can be considered as progress in oil-water separation achieved through modules 150 within the oil-water separation system 100.

[0083] In step 718, for example, the coalesced oil droplets are guided toward the inner surface of the vessel 101 by an oil scraper 110 arranged inside the vessel 101 and inclined downward relative to gravity toward the inner surface of the vessel 101.

[0084] In step 720, the water (separated from the feed stream) is discharged from vessel 101. In some embodiments, the oil concentration of the water discharged from vessel 101 in step 720 is less than 100 ppm. In some embodiments, the oil concentration of the water discharged from vessel 101 in step 720 is about 50 ppm.

[0085] Any step of method 700 may occur simultaneously with any other step of method 700. Any step of method 700 may be repeated to achieve a desired level of oil-water separation within the oil-water separation system 100.

[0086] While this specification contains numerous details of specific embodiments, these should not be construed as limiting the scope of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments. Certain features described herein, within the context of individual embodiments, may also be implemented in combination in a single embodiment. Conversely, different features described within the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments. Furthermore, although previously described features may be described as functioning in certain combinations and even initially claimed as such, in some cases, one or more features from the claimed combination may be removed from the combination, and the claimed combination may involve sub-combinations or variations of sub-combinations.

[0087] As used in this disclosure, unless the context clearly indicates otherwise, the terms “a,” “an,” or “the” are used to include one or more. Unless otherwise clearly indicated, the term “or” is used to mean a non-exclusive “or.” The expression “at least one of A and B” has the same meaning as “A, B, or A and B.” Furthermore, it should be understood that phrases or terms used in this disclosure, unless otherwise defined, are for descriptive purposes only and not restrictive. The use of any section headings is intended to aid in reading the document and should not be construed as restrictive; information relating to a section heading may appear within or outside that particular section.

[0088] As used in this disclosure, the terms “about” or “approximately” may allow for a degree of variation in the stated value or the stated range limit (e.g., within 10%, within 5%, or within 1%).

[0089] As used in this disclosure, the term “substantially” means the majority or most, such as at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more.

[0090] Values ​​expressed in range format should be interpreted flexibly to include not only the numerical values ​​explicitly stated as range limits, but also all individual numerical values ​​or subranges covered within that range, as if each numerical value and subrange were explicitly stated. For example, the range “0.1% to about 5%” or “0.1% to 5%” should be interpreted to include about 0.1% to about 5%, as well as individual values ​​(e.g., 1%, 2%, 3%, and 4%) and subranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. Unless otherwise indicated, the expression “X to Y” has the same meaning as “about X to about Y”. Similarly, unless otherwise indicated, the expression “X, Y, or Z” has the same meaning as “about X, about Y, or about Z”.

[0091] Specific embodiments of the subject matter have been described. Other embodiments, modifications, and arrangements of the described embodiments are within the scope of the appended claims and will be apparent to those skilled in the art. Although operations are depicted in a specific order in the drawings or claims, this should not be construed as requiring that such operations be performed in the specific order shown or in an ordered sequence, or requiring that all the operations shown can be performed (some operations may be considered optional) to achieve the desired result. In some cases, multitasking or parallel processing (or a combination of multitasking and parallel processing) may be advantageous and performed where deemed appropriate.

[0092] Furthermore, the separation or integration of the various system modules and components in the previously described embodiments should not be construed as requiring such separation or integration in all embodiments, but rather as meaning that the described components and systems can generally be integrated together or packaged into multiple products.

[0093] Therefore, the exemplary embodiments described above do not define or limit this disclosure. Other changes, substitutions, and modifications are possible without departing from the spirit and scope of this disclosure.

Claims

1. An oil-water separation system, comprising: The vessel includes a feed inlet dispenser, the feed inlet dispenser comprising: An inlet pipe configured to receive a feed flow including oil and water; A housing, wherein the outlet of the inlet pipe is connected to the housing, wherein the cross-sectional area of ​​the housing is larger than the cross-sectional area of ​​the inlet pipe relative to the flow of the feed stream, and the larger cross-sectional area of ​​the housing is configured to slow down the flow of the feed stream, thereby promoting the separation of oil and water; and Multiple blades are arranged within the housing, wherein the housing defines multiple perforations, and the multiple blades are configured to guide the flow of the supplied flow through the multiple perforations and exit the housing; A module, disposed within the vessel and downstream of the feed inlet dispenser, includes: Multiple coalescing plates are configured to promote the coalescence of oil; A first underflow baffle, the first underflow baffle being configured to direct fluid flow to the area below the first underflow baffle; A second underflow baffle, downstream of the first underflow baffle, defining a second plurality of perforations, the second underflow baffle configured to guide fluid flow below and through the second plurality of perforations; and An overflow baffle, disposed between the first underflow baffle and the second underflow baffle, the overflow baffle being configured to be submerged below the liquid level within the vessel and to guide fluid flow above the overflow baffle; and An oil scraper is arranged inside the vessel, extending longitudinally across the vessel and inclined downward relative to gravity toward the inner surface of the vessel. The oil scraper is configured to scrape oil from the oil-water interface layer formed within the vessel.

2. The system as claimed in claim 1, wherein, The module includes a porous or perforated wall disposed within the vessel and between the feed inlet dispenser and the plurality of coalescing plates.

3. The system of claim 1, comprising a plurality of modules, each of the plurality of modules being longitudinally spaced apart from each other within the vessel.

4. The system as described in claim 3, wherein, Each of the multiple coalescing plates is parallel to each other and tilted upwards relative to gravity.

5. The system as claimed in claim 1, wherein, One or more of the first underflow baffle, the second underflow baffle, or the overflow baffle include rounded ends.

6. The system as claimed in claim 1, wherein, The distance between the first underflow baffle and the overflow baffle and the distance between the overflow baffle and the second underflow baffle are substantially the same.

7. The system of claim 1, comprising a plurality of guide vanes disposed between the first underflow baffle and the second underflow baffle and above the overflow baffle relative to gravity, the plurality of guide vanes being configured to be submerged below the liquid level within the vessel.

8. The system of claim 7, wherein, The multiple guide vanes extend from the overflow baffle to the second underflow baffle.

9. The system of claim 7, wherein, The multiple guide vanes cross from the first underflow baffle to the second underflow baffle.

10. The system of claim 1, wherein, The outlet of the inlet pipe is connected to the lower portion of the housing of the feed inlet distributor, and the plurality of perforations defined by the housing of the feed inlet distributor are on the upper portion of the housing of the feed inlet distributor.

11. The system of claim 1, wherein, The oil skimmer extends longitudinally across the vessel over the area covering the housing of the feed inlet dispenser and the module.

12. The system of claim 1, wherein, The module includes a porous or perforated wall immediately upstream of the plurality of coalescing plates. This module is a first module. The system also includes a second module disposed within the vessel downstream of the first module. The second module is substantially identical to the first module. The oil skimmer extends longitudinally across the vessel over the area covering the housing of the feed inlet dispenser, the first module, and the second module.

13. The system of claim 1, wherein, The housing of the feed inlet dispenser is configured to be submerged below the liquid level within the vessel.

14. The system of claim 1, wherein, The plurality of coalescing plates are corrugated, and for each of the plurality of coalescing plates, the contact angle between the oil droplet and the surface of the corresponding coalescing plate is greater than 90 degrees.

15. A method comprising: The feed stream, including oil and water, is received through the inlet pipe; The feed flow is discharged from the outlet of the inlet pipe into the housing, the cross-sectional area of ​​which is larger than that of the inlet pipe relative to the direction of fluid flow, and the housing is arranged inside the vessel; The feed flow is guided by multiple blades arranged within the housing to exit the housing through multiple perforations defined by the housing; Through modules arranged inside the vessel, downstream of the shell, The oil droplets are coalesced by multiple coalescing plates in this module; as well as The coalescing oil droplets are guided by the multiple coalescing plates in an upward tilting direction opposite to gravity; The fluid flow is guided below the first underflow baffle by the module. The overflow baffle of this module guides the fluid flow to the area above the overflow baffle, which is downstream of the first underflow baffle; as well as The fluid flow is guided to the area below the second underflow baffle of the module, which is downstream of the overflow baffle; The oil droplets that have coalesced are guided toward the inner surface of the vessel by an oil scraper groove arranged inside the vessel, running longitudinally across the vessel, and tilting downward toward the inner surface of the vessel relative to gravity. as well as Drain the water from the vessel.

16. The method of claim 15, wherein, The feed stream includes up to 10% by volume of oil.

17. The method of claim 16, wherein, The oil concentration in the water discharged from this vessel is less than 50 parts by weight per million parts by weight.

18. The method of claim 17, wherein, The coalescence of these oil droplets involves receiving the oil droplets through the plurality of coalescing plates, and the oil droplets coalescing together as they pass through the plurality of coalescing plates.

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