In-line static mixer

Abstract

The present disclosure provides an in-line static mixer (100) comprising an outer tube (112) and an inner tube (104) positioned inside the outer tube and disposed coaxially with respect to the outer tube, with a space (104) between the inner tube and the outer tube. The inner tube is operable to receive and convey a hydrocarbon stream, and the outer tube is operable to receive and convey a diluent stream. At least one baffle (114) extends from the inner tube toward the outer tube and passes through at least a portion of the space operable to create a twisted flow of diluent from the flow of diluent. The twisted diluent stream and the hydrocarbon stream are mixed downstream of the outlet of the inner tube, where the twisted diluent stream forms a boundary layer along the inner surface of the outer tube to minimize fouling of liquids or droplets from the hydrocarbon stream after mixing.

Description

Background Art Technical Field

[0001] The present disclosure relates generally to static mixers, and more particularly, but not exclusively, to in-line static mixers having flow twisters for mixing fluid streams.

[0002] Description of the Prior Art

[0003] Static mixers are known for use in petrochemical processing, and in particular for the production of ethylene and / or propylene. Conventional static mixers mix two fluid streams, such as a gaseous diluent stream and a feed stream that is liquid, partially liquid and partially vaporous, or contains droplets. The combined feed-diluent mixture is then provided to a heater to produce a heated feed-diluent mixture for further processing.

[0004] Existing mixer designs mix the streams at or immediately after the mechanical components. More specifically, such designs mix the diluent and hydrocarbon feedstock by direct contact within the mixing device, and then indirectly heat the mixture in the tubes of the convection section. In fact, the liquid or droplets do not vaporize immediately, but require a certain distance to reach thermal equilibrium, so that the liquid will inevitably contact the heated walls of the convection section tubes and leave scaling deposits. In other words, if there are any droplets, the droplets will hit the mechanical components or contact surfaces of the mechanical components downstream of the mixer, which will cause scaling over time. Such deposits must be cleaned and removed regularly, which will increase operating costs, reduce yields over time, and increase maintenance downtime. Alternatively, such deposits may restrict flow and reduce the throughput of the heater, thereby reducing yield. In addition, some static mixers can cause high pressure drops, which can reduce production or increase compressor operating costs to change the pressure to obtain the desired yield. In response, certain solutions have been proposed, but these solutions have various defects and disadvantages.

[0005] For example, one solution is a device that promotes mixing at different stages along the fluid flow to help provide a more uniform mixing of the single-phase flow. In such examples, the concentration profile or temperature profile of the fluid in the direction of flow is constant. However, fouling deposits may still occur at various mixing stages, and individual stages may also result in high pressure drops.

[0006] Alternative solutions promote mixing of two or a single stream by creating stronger turbulence through the device and changing the flow area along the flow path. However, this solution also creates a high pressure drop. Other solutions include coaxial static mixers, where the two streams are in contact inside the device, but such solutions are also prone to leaving fouling deposits. In some variations, coaxial static mixers create two counter-rotating streams, which result in more mixing with each other, but applicability may be limited to streams that do not have fouling potential.

[0007] Other mixers promote the mixing of single streams. Such mixers contain spoilers that exert forces on the fluid stream from an external source to produce wave-like mixing. Such solutions increase the overall complexity of the mixer and may produce high pressure drops. In some variations, the single stream fluid flow is instead divided into different parts. In the direction of flow, the flow area of ​​each part changes, which changes the flow rate, which is higher in some parts and lower in others. The streams from the various parts meet and mix with each other, but fouling may occur at the location of this mutual mixing.

[0008] Some existing static mixers have a stack of mixing elements or similar structures. As the fluid flows through the elements, adjacent elements will direct the flow in opposite directions. While this solution can reduce fouling for a single stream, it is prone to high pressure drops associated with the change in flow direction.

[0009] Therefore, there is a need for a static mixer that overcomes the drawbacks and disadvantages of known static mixers. Summary of the invention

[0010] The present disclosure generally relates to in-line static mixing devices, systems and methods for hydrocarbon processing applications. In particular, the mixer of the present disclosure may include a flow twisting device, which is arranged in any one or both of the tubes with a spiral blade shape factor for generating a swirl in the mixer, which forms a boundary layer with a high dilution steam content and a low hydrocarbon content along the mechanical components. Such an arrangement advantageously mixes the streams without a significant pressure drop, while also minimizing contact between hydrocarbons and mechanical components to reduce scaling or impurity deposits. In particular, the concept of the present disclosure minimizes any potential hydrocarbon scaling or any impurity deposits on the inner surface of the heating coil.

[0011] In one or more embodiments, a method for introducing a liquid or partially liquid hydrocarbon feedstock into a cracking heater together with a diluent to produce a superheated feedstock-diluent mixture is provided. The diluent stream and the hydrocarbon stream are coaxially introduced into a convection section, with the vapor diluent on the outside and the liquid or partially liquid hydrocarbon stream on the inside. A swirl may be applied to either or both of the hydrocarbon or diluent streams. The cracking heater has a heating surface in the convection section to preheat the hydrocarbon feedstock. Dilution steam is applied to the hydrocarbon to ideally promote vaporization of the hydrocarbons of the liquid feed to the heater and to reduce the hydrocarbon partial pressure in the stream to obtain an optimal yield, such as ethylene and / or propylene yield.

[0012] In one or more embodiments, the mixing device includes an in-line flow twisting device. The mixing device is installed in a straight line with the hydrocarbon stream and includes a branch connection for mixing dilution steam with hydrocarbons. Before the steam mixes with the hydrocarbons, the device generates a vortex near the inner surface of the heating coil and forms a boundary layer with a high dilution steam content and a low hydrocarbon content. The boundary layer delays, prevents or minimizes hydrocarbon droplets from contacting the inner surface of the heater coil before the hydrocarbons are fully vaporized. At the same time, the twisted dilution steam flow will promote the flow mixing between the desired hydrocarbons and the dilution steam. It is preferred to fully vaporize the droplets before the droplets enter the heat receiving surface section to reduce scaling and impurity deposits. In one or more embodiments of the device, any residual hydrocarbon droplets will be separated by the dilution steam boundary layer and fully vaporized before reaching the heat receiving surface section. Therefore, the device minimizes the risk of surface scaling caused by heavy hydrocarbon components or impurities. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figures 1A to 1C is a schematic diagram of a known static mixer.

[0014] Figure 2 and Figure 3 is a schematic diagram of an embodiment of an in-line flow twister with spiral baffles according to the present disclosure.

[0015] Figure 4 is a schematic diagram of an embodiment of an inline flow mixer without helical baffles according to the present disclosure.

[0016] Figure 5 is a schematic diagram of an embodiment of an in-line flow twister having a twister plate inside the inner tube of the mixer according to the present disclosure.

[0017] Figure 6 is a schematic diagram of an embodiment of an in-line flow twister having a twister plate inside the inner tube of the mixer and baffles according to the present disclosure.

[0018] 7A to 7C is a schematic diagram of the installation location and orientation of an in-line flow twister according to the present disclosure.

[0019] Figures 8 to 10 is a computational fluid dynamics simulation of flow through an embodiment of a mixer according to the present disclosure. DETAILED DESCRIPTION

[0020] The present disclosure will continue to describe certain non-limiting examples of technologies that may be particularly advantageous for petrochemical processing and refining, such as at least with respect to the production of ethylene and / or propylene using steam cracking heaters. However, it should be understood that the concepts of the present disclosure can be applied to a wide range of technologies and industries. In particular, the concepts of the present disclosure can be equally applied to any industry or technology that utilizes a firing or heating process that involves mixing two streams and is particularly used for two-phase streams in order to completely vaporize the streams after mixing. These concepts can be installed in new heaters, or the technology can be used to retrofit existing heaters to improve heater performance and reduce heater downtime for maintenance.

[0021] Figures 1A to 1C is a schematic diagram of a known static mixer 20 to provide additional background regarding the benefits and advantages of the concepts of the present disclosure. In the known static mixer 20, a hydrocarbon stream 22 (stream A) and a dilution stream 24 (stream B) are mixed via a direct pipe connection. Figures 1A to 1C The change of mixing position and mixer orientation is provided. The combined mixture is then provided to the heat receiving surface 28 along the pipeline 26 to heat the mixture for further downstream processing. When the hydrocarbon stream 22 contains heavy components or impurities, droplets, especially droplets from the hydrocarbon stream 22, can wet the inner surface of the pipeline 26 and accumulate. When the liquid moves to the heat receiving surface 28, the combination of the incident heat and the liquid in the pipeline 26 causes scaling, which eventually restricts the flow through the pipeline 26 and the heat receiving surface 28 (which can also be the pipeline 28). As used herein, "scaling" can refer to insoluble materials or precipitates accumulated on mechanical components, and includes but is not limited to scale, corrosion, sludge and debris, and the evaporation of higher molecular weight components of hydrocarbon raw materials at the heated surface to form deposits, which gradually accumulate and harden over time, resulting in high pressure drop and poor heat transfer in the heat receiving section. In response, the mixer 20 and the entire system may need to be shut down for cleaning and maintenance, or the heater throughput may be reduced due to the reduction of fluid flow.

[0022] Known mixers, such as mixer 20, perform mixing at the turbulators or produce mixing that does not prevent droplets from contacting downstream mechanical surfaces. As a result, operation of known mixers is highly likely to result in fouling of mechanical components and the disadvantages associated therewith.

[0023] In contrast, the concepts of the present disclosure keep the two streams separate to prevent or minimize droplet vaporization before the flow pattern is fully formed. Once the flow pattern is formed, the two streams mix, but the stream with the droplets is kept away from the mechanical surface, or contact with the mechanical surface is delayed (if any) to minimize potential fouling.

[0024] Figure 2 and Figure 3 is a schematic diagram of one or more embodiments of an inline flow twister 100 (which may also be referred to herein as an inline mixer 100 or mixer 100) according to the present disclosure. A hydrocarbon stream 102 (stream A), which may contain droplets, flows through one or more inner tubes 104. A diluent stream 106 (stream B) flows through a nozzle 108 and flows through a space 110 between the inner tube 104 and an outer tube 112. In one embodiment, the diluent stream is a gaseous stream, such as, for example, steam, which causes vaporization of the mixed hydrocarbon stream 102, as further described herein. The diluent stream 106 flows through and around a plurality of spiral baffles 114. In some embodiments, the mixer 100 includes 3 or more baffles 114, or more preferably, includes between 6 and 8 baffles 114. Of course, the mixer 100 may also include a selected number of baffles 114 that is more or less than the above non-limiting examples.

[0025] The baffle 114 can be disposed about and coupled to the inner tube 104 and extend in a complete and continuous spiral rotation about the inner tube 104 along at least a portion of the length of the inner tube 104. In one embodiment, the baffle 114 extends along less than half, half, more than half, and up to the entire length of the inner tube 104. In addition, the baffle 114 can have a selected height relative to the inner tube 104 and the outer tube 112 (i.e., the baffle 114 extends from the inner tube 104 through a selected amount of the space 110 between the inner tube 104 and the outer tube 112). In some embodiments, the baffle 114 is longitudinally (i.e., at a selected height) extending from the inner tube 104 to the outer tube 112. Figure 2 In the vertical direction in the orientation of the inner tube 104, the baffle 114 may extend to less than half, half, more than half, or through any entirety of the space 110 (in this case, the baffle 114 is in contact with the inner tube 104 and in contact with or very close to the outer tube 112). In one embodiment, the baffle 114 is welded only to the inner tube 104, and there is a manufacturing or manufacturing tolerance between the outer peripheral edge of the baffle 114 and the inner surface of the outer tube 112. In addition, the baffle 114 may be located at one end of the inner tube 104 closest to the mixing interface between the streams 102 and 106, such as Figure 3 The baffle 114 may be aligned with a flow axis 118 defined by the hydrocarbon stream 102 (i.e., at Figure 2The spiral baffles 114 are angularly aligned with the tubes 104, 112 and the horizontal axis passing through the center of the inner tube in the orientation of the spiral baffles 114, which is preferably between 30 and 45 degrees, including all intermediate values ​​with at least two decimal places, and including the extreme values. In some embodiments, the angle 116 is less than 30 degrees or greater than 45 degrees. In addition, each baffle 114 may have a selected spacing relative to other baffles 114, which may be as low as 6 inches to 1 foot or may be greater than one foot, such as at least 3 feet, 4 feet, 5 feet, or more. The angular alignment of the spiral baffles 114 relative to the tubes 104, 112 and the spacing between the plates 114 achieve a twisted flow of the diluent stream 106 along the space 110 during operation.

[0026] In one embodiment, the length of the inner tube 104 is less than the length of the outer tube 112, so that the inner tube 104 terminates inside the outer tube 112 (i.e., has an outlet). The diluent stream 106 flows through the space 110 and flows through the baffle 114 to form a twisted flow. When the twisted flow is fully formed, the two streams 102, 106 mix at the outlet of the inner tube 104. The twisted flow of the diluent stream 106 generated by the baffle 114 travels along the inner surface 119 of the outer tube 112 and forms a boundary layer along the inner surface of the outer tube 112, which is Figure 2 104. The boundary layer 121 prevents or minimizes liquid and / or droplets in the hydrocarbon stream 102 exiting the inner tube 104 from contacting and contaminating the inner surface 119. In addition, the liquid and / or droplets reaching the boundary layer 121 may be vaporized by the twisted flow of the diluent 106, which may be heated before being provided to the outer tube 112. Because the tubes 104, 112 are coaxially arranged and the hydrocarbon stream 102 passes through the inner tube 102 without a significant change in direction, there is minimal pressure drop in the mixer 100. In addition, the twisted flow created by the baffles 114 also advantageously mixes the streams 102, 106.

[0027] like Figure 4 As shown, in some embodiments, the mixer 100 may include only two coaxial tubes, namely the inner tube 104 and the outer tube 112, without the baffle 114. Figure 5 As shown, the mixer 100 may include only a twister plate 120 (which may also be referred to herein as a twist baffle 120) inside the inner tube 104 instead of the baffle 114. In one embodiment, the twister plate 120 may have some or all of the same features as the baffle 114 described above, except for their location in the mixer 100.

[0028] In one embodiment, the mixer 100 includes both a twister plate 120 and a helical baffle 114 inside the inner tube 104, such as Figure 6The helical baffles 114 and the torsional baffles 120 may have the same or different angles relative to the flow axis 118 and may generate rotating or torsional flows in the inner coaxial tube 104 and the outer coaxial tube 112 in the same or opposite directions.

[0029] The mixer 100 may be mounted in a variety of positions and orientations depending on design considerations and available machine space. Fig. 7A In the embodiment, the mixer 100 is mounted and aligned vertically according to the ordinary meaning of "vertical" (i.e., gravity pulls objects downward along a vertical path) to have an upward flow after mixing to help suspend droplets during vaporization. In one embodiment, the tubing 122 from the mixer 100 to the heat receiving surface 124 can have a linear length of 10 to 15 times the inner diameter of the tubing 122 before any flow disturbance and a total linear length of 20 to 30 times the inner diameter to allow space for vaporization to complete before entering the heat receiving surface section 124. Fig. 7A The arrangement may provide more time for process streams containing very heavy components to fully vaporize before reaching the heat receiving surface 124 to avoid fouling.

[0030] The mixer 100 can also be used as Figure 7B The installation shown has a horizontal arrangement. In one embodiment, it is preferred to have similar straight pipe lengths and total linear pipe lengths after mixing. Such an arrangement can allow a process stream with a moderately heavy component to be fully vaporized before entering the heat receiving surface 124.

[0031] Where machine space may be limited, the mixer 100 may be Figure 7C More specifically, the mixer 100 may be mounted directly in front of a straight heat receiving tube leading to the heat receiving surface 124. In such an embodiment, it is preferred that the baffle 114 is oriented relative to the flow axis 118 ( Figure 2 ) has a greater angle 116 to provide a more torsional flow path. The more intense flow path increases the heat transfer coefficient and allows the diluent stream 106 to reach a higher temperature when mixing with the hydrocarbon stream 102 ( Figure 2 ). The larger angle will also promote stronger mixing between the streams 102, 106. The higher temperature of the diluent stream 106 and the stronger mixing will help to vaporize the droplets faster and minimize the risk of fouling at the heating surface 124.

[0032] Figures 8 to 10 is the output of a computational fluid dynamics (CFD) simulation showing the flow trajectories obtained using an embodiment of the mixer 100 described herein. The simulation confirms that the tube design of the mixer 100 effectively prevents or minimizes the center flow in the inner tube 104 from reaching the outer tube 112 ( Figure 2) to prevent or minimize fouling. In particular, embodiments that include twisted flow (whether by helical baffles 114, twisting plates 120, or both) promote faster mixing while further improving separation of the center flow from the inner surface of the outer tube 112 ( Figure 2 ).exist Figures 8 to 10 In the diagram, the boundary layer with high diluent content and low hydrocarbon content is represented by the outer black line, where the hydrocarbon stream is the inner lighter line.

[0033] In view of the above, the mixer 100 described herein has many benefits and advantages. For example, the mixer 100 can keep the two streams separated and can form a flow pattern that keeps the droplets in suspension and enables complete vaporization before the droplets contact the solid surface. In addition, the two streams can be intentionally not completely mixed before leaving the mixing device, but the high temperature of the convection section wall is used to produce a diluent boundary layer that is quickly heated to a high temperature. Such an arrangement essentially utilizes the Leidenfrost effect, because the diluent is heated to a high temperature at the inner wall of the tube, and the vaporization of the droplets in the mixed fluid stream is more favorable than the vaporization of the droplets at the tube wall.

[0034] In addition, the concentration and temperature profile may not be constant in the mixer in order to favor vaporization of droplets in the main stream rather than at heated surfaces downstream of the mixing device. In some embodiments, the two streams may be mixed only at the outlet of the device once the streams are fully formed to improve vaporization.

[0035] In some embodiments, the mixer of the present disclosure mixes two streams: one is gaseous and the other contains liquid or droplets. At the mixing point, the liquid or droplets may vaporize. During the vaporization process, any heavy components in the liquid may contaminate mechanical surfaces, such as the inner surface of a carrier tube, container, or mixer assembly. The mixer of the present disclosure includes two coaxial pipes, which keep the two streams separated before mixing. The non-fouling stream flows in the outer pipe, and the flow that may foul flows in the inner pipe. Between the inner pipe and the outer pipe, the mixer may include a spiral baffle that will produce a twisted flow in the non-fouling flow before leaving the coaxial pipe section. The twisted flow will form a boundary layer, which can prevent or minimize the flow with liquid and / or droplets from contacting the pipe surface. The droplets will gradually mix with the stream near the pipe surface and vaporize to minimize the possibility of liquid contacting the pipe surface (which may cause fouling).

[0036] In one embodiment, a mixer includes: an outer tube; a nozzle connected to the outer tube; an inner tube, which is inside the outer tube and has an inlet, the inner tube being operable to receive a hydrocarbon stream through the inlet and convey the hydrocarbon stream from the inlet of the inner tube to an outlet along a flow path through the inner tube; a space between the inner tube and the outer tube, the outer tube being operable to receive a diluent stream via the nozzle and convey the diluent stream through the space; and at least one baffle connected to the inner tube and extending from the inner tube toward the outer tube through at least a portion of the space, the at least one baffle being operable to generate a twisted diluent stream from the diluent stream, wherein the twisted diluent stream and the hydrocarbon stream are mixed downstream of the outlet of the inner tube, wherein the twisted diluent stream forms a boundary layer along the inner surface of the outer tube.

[0037] In one embodiment, the inner tube is coaxially disposed relative to the outer tube, the inner tube has a length less than the outer tube, and the boundary layer is operable to prevent or minimize liquid in the hydrocarbon stream from contacting an inner surface of the outer tube.

[0038] In one embodiment, the at least one baffle is a plurality of helical baffles extending around the inner tube, the plurality of helical baffles having an angle of between 30 degrees and 45 degrees, inclusive, relative to a flow axis through the inner tube.

[0039] In one embodiment, the inner tube comprises at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon flow.

[0040] In one embodiment, the at least one baffle is a helical baffle on the outer surface of the inner tube.

[0041] In one embodiment, the boundary layer is operable to prevent or minimize liquid in the hydrocarbon stream from contacting the inner surface of the outer tube.

[0042] In one embodiment, a mixer includes: an outer tube; an inner tube, which is arranged inside the outer tube and coaxially relative to the outer tube, the inner tube having an inlet and being operable to receive a hydrocarbon stream through the inlet and convey the hydrocarbon stream from the inlet of the inner tube positioned inside the outer tube to an outlet along a flow path passing through the inner tube; and a space between the inner tube and the outer tube, the outer tube being operable to receive a diluent stream and convey the diluent stream through the space, wherein the diluent stream and the hydrocarbon stream are mixed downstream of the outlet of the inner tube, wherein the diluent stream forms a boundary layer along the inner surface of the outer tube to prevent or minimize liquid or droplets from the hydrocarbon stream from contacting the inner surface of the outer tube.

[0043] In one embodiment, the mixer further includes at least one baffle, which is connected to the inner tube and extends from the inner tube toward the outer tube through at least a portion of the space, and the at least one baffle is operable to generate a twisted diluent flow from the diluent feed flow, wherein the twisted diluent flow forms the boundary layer.

[0044] In one embodiment, the at least one baffle is a plurality of helical baffles extending around the inner tube, the plurality of helical baffles having an angle of between 30 degrees and 45 degrees, inclusive, relative to a flow axis through the inner tube.

[0045] In one embodiment, the inner tube comprises at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon flow.

[0046] In one embodiment, the direction of rotation of the twisted diluent flow is the same as the direction of rotation of the twisted hydrocarbon flow.

[0047] In one embodiment, the direction of rotation of the twisted diluent flow is opposite to the direction of rotation of the twisted hydrocarbon flow.

[0048] In one embodiment, the inner tube comprises at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon flow.

[0049] In one embodiment, a mixer includes: an outer tube; an inner tube arranged inside the outer tube, the inner tube being operable to receive a hydrocarbon stream and convey the hydrocarbon stream through the inner tube; and a space between the inner tube and the outer tube, the outer tube being operable to receive a diluent stream and convey the diluent stream through the space, wherein the diluent stream and the hydrocarbon stream are mixed downstream of an outlet of the inner tube, wherein the diluent stream is configured to generate a boundary layer along an inner surface of the outer tube to prevent or minimize liquid or droplets from the hydrocarbon stream from contacting the inner surface of the outer tube.

[0050] In one embodiment, the inner tube comprises at least one baffle on an outer side surface of the inner tube, the at least one baffle being operable to generate a twisted diluent flow from the diluent flow generating the boundary layer.

[0051] In one embodiment, the at least one baffle is arranged on the outer side surface of the inner tube at an angle of between 30 degrees and 45 degrees, inclusive, relative to a flow axis through the inner tube.

[0052] In one embodiment, the inner tube comprises at least one twister plate.

[0053] In one embodiment, the inner tube comprises at least one twister plate inside the inner tube operable to produce a twisted hydrocarbon flow, and at least one baffle outside the inner tube operable to produce a twisted diluent flow, the twisted diluent flow producing the boundary layer.

[0054] In one embodiment, the inner tube is arranged coaxially with respect to the outer tube.

[0055] In one embodiment, a portion of the length of the inner tube is received within the outer tube, and the inner tube further includes a flow control device, which is at least one baffle or at least one twister plate, and the flow control device extends along the entirety of the portion that is less than the length of the inner tube.

[0056] In the above description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure can be practiced without these specific details. In other cases, well-known structures associated with the present technology are not described in detail to avoid unnecessarily obscuring the description of the embodiments of the present disclosure.

[0057] Certain words and phrases used in this specification are set forth below. As used throughout this document, including the claims, the singular forms "a," "an," and "the" include plural referents unless otherwise indicated. Any features and elements described herein may be singular, for example, a shell may refer to one shell. The terms "include" and "comprising" and their derivatives are meant to include, but are not limited to.

[0058] The use of ordinal numbers such as first, second, third, etc. does not necessarily imply a sequential ordering connotation but may simply distinguish multiple instances of an action or similar structures or materials.

[0059] Throughout this specification, claims, and drawings, unless the context clearly dictates otherwise, the following terms adopt the meanings explicitly associated herein. The term "herein" refers to the specification, claims, and drawings associated with the present application. The phrases "in one embodiment," "in another embodiment," "in various embodiments," "in some embodiments," "in other embodiments," and their other derivatives refer to one or more features, structures, functions, limitations, or characteristics of the present disclosure, and are not limited to the same or different embodiments, unless the context clearly dictates otherwise. As used herein, the term "or" is an inclusive "or" operator and is equivalent to the phrases "A or B, or both" or "A or B or C, or any combination thereof," and lists with additional elements are treated similarly.

[0060] The terms "top", "bottom", "upper", "lower", "up", "down", "above", "below", "left", "right" and other similar derivatives adopt their common meaning as direction or position indications, for example, gravity pulls objects downward, and left refers to the direction to the west when facing north in a cardinal direction scheme. These terms are not limited to possible orientations explicitly disclosed, implicitly disclosed, or inherently disclosed in the present disclosure, and any aspect of the embodiments of the present disclosure can be arranged in any orientation unless the context clearly dictates otherwise.

[0061] Unless the context clearly dictates otherwise, relative terms such as "approximately," "substantially," and other derivatives are interpreted to include the normal error range or manufacturing tolerance due to minor differences and variations in manufacturing, and when used to describe a value, amount, quantity, or dimension, generally refer to a value, amount, quantity, or dimension within plus or minus 5% of the value, amount, quantity, or dimension. It should also be understood that any specific dimensions of components or features provided herein are only for illustrative purposes with reference to the various embodiments described herein, and therefore, unless the context clearly dictates otherwise, dimensions greater than or less than the stated dimensions are explicitly contemplated in this disclosure. Unless the context clearly dictates otherwise, all ranges of dimensions or other values ​​include all possible intermediate values ​​and limiting values.

[0062] This application claims priority to U.S. Provisional Application No. 63 / 351,755 filed in the U.S. Patent and Trademark Office on June 13, 2022, the entire contents of which are incorporated herein by reference.

[0063] These and other changes can be made to the embodiments in light of the above detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and claims, but should be construed to encompass all possible embodiments and the full range of equivalents to which the claims are entitled. Therefore, the breadth and scope of the disclosed embodiments should not be limited by any of the above described embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims

1. A mixer, comprising: External pipe; a nozzle in communication with the outer tube; an inner tube within the outer tube and having an inlet, the inner tube being operable to receive a hydrocarbon stream through the inlet and convey the hydrocarbon stream from the inlet to an outlet of the inner tube along a flow path through the inner tube; a space between the inner tube and the outer tube, the outer tube being operable to receive a diluent stream via the nozzle and convey the diluent stream through the space; and at least one baffle coupled to the inner tube and extending from the inner tube toward the outer tube through at least a portion of the space, the at least one baffle being operable to generate a twisted diluent flow from the diluent stream, Wherein the twisted diluent flow and the hydrocarbon stream are configured to mix downstream of the outlet of the inner tube, wherein the twisted diluent flow forms a boundary layer along the inner surface of the outer tube.

2. The mixer of claim 1 , wherein the inner tube is coaxially arranged relative to the outer tube, the length of the inner tube is less than the length of the outer tube, and the boundary layer is operable to prevent or minimize liquid in the hydrocarbon stream from contacting the inner surface of the outer tube.

3. The mixer of claim 1, wherein the at least one baffle is a plurality of helical baffles extending around the inner tube, the plurality of helical baffles having an angle between 30 degrees and 45 degrees, inclusive, relative to a flow axis through the inner tube.

4. The mixer of claim 1, wherein the inner tube comprises at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.

5. The mixer of claim 1, wherein the at least one baffle is a helical baffle on an outer surface of the inner tube.

6. The mixer of claim 1, wherein the boundary layer is operable to prevent or minimize liquid in the hydrocarbon stream from contacting an inner surface of the outer tube.

7. A mixer comprising: External pipe; an inner tube disposed coaxially within and relative to the outer tube, the inner tube having an inlet and operable to receive a hydrocarbon stream through the inlet and convey the hydrocarbon stream from the inlet of the inner tube to an outlet along a flow path through the inner tube, the outlet of the inner tube being positioned within the outer tube; and a space between the inner tube and the outer tube, the outer tube being operable to receive a diluent stream and convey the diluent stream through the space, The diluent stream and the hydrocarbon stream are mixed downstream of the outlet of the inner tube, wherein the diluent stream forms a boundary layer along the inner surface of the outer tube to prevent liquid or droplets from the hydrocarbon stream from contacting the inner surface of the outer tube.

8. The mixer according to claim 7, further comprising: at least one baffle coupled to the inner tube and extending from the inner tube toward the outer tube through at least a portion of the space, the at least one baffle being operable to generate a twisted diluent flow from the diluent stream, Wherein the twisted diluent flow forms the boundary layer.

9. The mixer of claim 8, wherein the at least one baffle is a plurality of helical baffles extending around the inner tube, the plurality of helical baffles having an angle of between 30 degrees and 45 degrees, inclusive, relative to a flow axis through the inner tube.

10. The mixer of claim 8, wherein the inner tube comprises at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.

11. The mixer of claim 10, wherein the direction of rotation of the twisted diluent flow is the same as the direction of rotation of the twisted hydrocarbon flow.

12. The mixer of claim 10, wherein the direction of rotation of the twisted diluent flow is opposite to the direction of rotation of the twisted hydrocarbon flow.

13. The mixer of claim 7, wherein the inner tube comprises at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.

14. A mixer comprising: External pipe; an inner tube disposed within the outer tube, the inner tube operable to receive a hydrocarbon stream and convey the hydrocarbon stream through the inner tube; and a space between the inner tube and the outer tube, the outer tube being operable to receive a diluent stream and convey the diluent stream through the space, The diluent stream and the hydrocarbon stream are mixed downstream of the outlet of the inner tube, wherein the diluent stream is configured to create a boundary layer along the inner surface of the outer tube to prevent or minimize liquid or droplets from the hydrocarbon stream from contacting the inner surface of the outer tube.

15. The mixer of claim 14, wherein the inner tube includes at least one baffle on an outer side surface of the inner tube, the at least one baffle being operable to create a twisted diluent flow from the diluent stream that creates the boundary layer.

16. The mixer of claim 15, wherein the at least one baffle is disposed on the outside surface of the inner tube at an angle of between 30 degrees and 45 degrees, inclusive, relative to a flow axis through the inner tube.

17. The mixer of claim 14, wherein the inner tube comprises at least one twister plate.

18. A mixer according to claim 14, wherein the inner tube includes at least one twister plate inside the inner tube that is operable to produce a twisted hydrocarbon flow, and at least one baffle outside the inner tube that is operable to produce a twisted diluent flow, wherein the twisted diluent flow produces the boundary layer.

19. The mixer of claim 14, wherein the inner tube is coaxially arranged relative to the outer tube.

20. The mixer of claim 14, wherein a portion of the length of the inner tube is received within the outer tube, and the inner tube further comprises a flow control device, the flow control device being at least one baffle or at least one twister plate, the flow control device extending along an entirety of the portion that is less than the length of the inner tube.

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