INLINE STATIC MIXER
20230405536 ยท 2023-12-21
Inventors
- Baozhong Zhao (Bloomfield, NJ, US)
- Xueping Li (Bloomfield, NJ, US)
- Kishan Thakurdin (Bloomfield, NJ, US)
- Alejandro Carrillo (Bloomfield, NJ, US)
- Richard Jibb (Bloomfield, NJ, US)
Cpc classification
B01F25/313
PERFORMING OPERATIONS; TRANSPORTING
B01F25/435
PERFORMING OPERATIONS; TRANSPORTING
B01F23/232
PERFORMING OPERATIONS; TRANSPORTING
B01F2025/913
PERFORMING OPERATIONS; TRANSPORTING
B01F2215/0422
PERFORMING OPERATIONS; TRANSPORTING
International classification
B01F25/435
PERFORMING OPERATIONS; TRANSPORTING
B01F25/431
PERFORMING OPERATIONS; TRANSPORTING
B01F23/232
PERFORMING OPERATIONS; TRANSPORTING
Abstract
An inline static mixer includes an outer tube and an inner tube positioned inside the outer tube and arranged coaxially with respect to the outer tube with a space between the inner and outer tubes. 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 extends from the inner tube toward the outer tube and through at least a portion of the space that is operable to generate a twisted diluent flow from the diluent stream. The twisted diluent flow and the hydrocarbon stream are mixed downstream of an outlet of the inner tube with the twisted diluent flow forming a boundary layer along an internal surface of the outer tube to minimize fouling from liquid or liquid droplets of the hydrocarbon stream after mixing.
Claims
1. A mixer, including: an outer tube; a nozzle in communication with the outer tube; an inner tube inside the outer tube and having an inlet, the inner tube operable to receive a hydrocarbon stream through the inlet and convey the hydrocarbon stream along a flow path through the inner tube from the inlet to an outlet of the inner tube; a space between the inner tube and the outer tube, the outer tube 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 operable to generate a twisted diluent flow from the diluent stream, wherein the twisted diluent flow and the hydrocarbon stream are configured to be mixed downstream of the outlet of the inner tube with the twisted diluent flow forming a boundary layer along an internal surface of the outer tube.
2. The mixer of claim 1, wherein the inner tube is arranged coaxially with respect to the outer tube, the inner tube having a length that is less than a length of the outer tube, the boundary layer operable to prevent or minimize liquid in the hydrocarbon stream from contacting an internal 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 relative a flow axis through the inner tube between and including 30 degrees and 45 degrees.
4. The mixer of claim 1, wherein the inner tube includes 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 exterior 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 internal surface of the outer tube.
7. A mixer, including: an outer tube; an inner tube inside the outer tube and arranged coaxially with respect 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 along a flow path through the inner tube from the inlet to an outlet of the inner tube, the outlet of the inner tube positioned inside the outer tube; and a space between the inner tube and the outer tube, the outer tube 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 with the diluent stream forming a boundary layer along an internal surface of the outer tube to prevent liquid or liquid droplets from the hydrocarbon stream from contacting the internal surface of the outer tube.
8. The mixer of 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 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 relative a flow axis through the inner tube between and including 30 degrees and 45 degrees.
10. The mixer of claim 8, wherein the inner tube includes at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.
11. The mixer of claim 10, wherein a direction of rotation of the twisted diluent flow is the same as a direction of rotation of the twisted hydrocarbon flow.
12. The mixer of claim 10, wherein a direction of rotation of the twisted diluent flow is opposite a direction of rotation of the twisted hydrocarbon flow.
13. The mixer of claim 7, wherein the inner tube includes at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.
14. A mixer, comprising: an outer tube; an inner tube arranged within 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 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 with the diluent stream configured to produce a boundary layer along an internal surface of the outer tube to prevent or minimize liquid or liquid droplets from the hydrocarbon stream from contacting the internal surface of the outer tube.
15. The mixer of claim 14, wherein the inner tube includes at least one baffle on an outer surface of the inner tube, the at least one baffle operable to generate a twisted diluent flow from the diluent stream that produces the boundary layer.
16. The mixer of claim 15, wherein the at least one baffle is arranged on the outer surface of the inner tube at an angle relative to a flow axis through the inner tube between and including 30 degrees and 45 degrees.
17. The mixer of claim 14, wherein the inner tube includes at least one twister plate.
18. The mixer of claim 14, wherein the inner tube includes at least one twister plate internal to the inner tube operable to produce a twisted hydrocarbon flow and at least one baffle external to the inner tube operable to produce a twisted diluent flow that produces the boundary layer.
19. The mixer of claim 14, wherein the inner tube is arranged coaxially with respect to the outer tube.
20. The mixer of claim 14, wherein a portion of a length of the inner tube is received within the outer tube, and the inner tube further includes a flow control device being at least one baffle or at least one twister plate, the flow control device extending along less than an entirety of the portion of the length of the inner tube.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
DETAILED DESCRIPTION
[0019] The present disclosure will proceed to describe certain non-limiting examples of the technology 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 a steam cracking heater. However, it will be appreciated that the concepts of the disclosure can be applied to a broad range of technologies and industries. In particular, the concepts of the disclosure can be applied equally to any industry or technology utilizing a fired or heating process that involves mixing of two streams and in particular, for two phases of flow in order to fully vaporize the flows after the mixing. Such concepts can be installed in new heaters, or existing heaters can be retrofitted with the technology to improve the heater performance and reduce heater downtime for maintenance.
[0020]
[0021] Known mixers, such as mixer 20, perform mixing at the flow spoiler or create mixing that does not prevent the liquid droplets from contacting downstream mechanical surfaces. As a result, operation of known mixers is highly likely to lead to fouling of the mechanical components and the disadvantages associated with the same.
[0022] In contrast, the concepts of the disclosure keep the two streams separated to prevent or minimize droplet vaporization before the flow pattern is fully developed. Once the flow pattern is developed, the two stream are mixed, but the stream with liquid droplets is kept away from mechanical surfaces, or contact with mechanical surfaces is delayed, if any, to minimize potential fouling.
[0023]
[0024] The baffle plates 114 may be arranged around, and coupled to, the inner tube 104 and extend around the inner tube 104 in complete and continuous helical revolutions along at least a portion of a length of the inner tube 104. In an embodiment, the baffle plates 114 extend along less than half, half, or more than half and up to an entirety of the length of the inner tube 104. Further, the baffle plates 114 may have a selected height relative to the inner tube 104 and the outer tube 112 (i.e., the baffle plates 114 extend 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 plates 114 extend longitudinally (i.e., in a vertical direction in the orientation of
[0025] In an embodiment, the length of the inner tube 104 is less than the length of the outer tube 112 such that the inner tube 104 terminates (i.e., has an outlet) inside the outer tube 112. The diluent stream 106 flows through the space 110 and through the baffle develops 114 to develop a twisted flow. After the twisted flow is fully developed, the two streams 102, 106 mix at the outlet of the inner tube 104. The twisted flow of the diluent stream 106 that is created by the baffles 114 travels along an interior surface 119 of the outer tube 112 and forms a boundary layer along the internal surface of the outer tube 112 that is represented in
[0026] As shown in
[0027] In an embodiment, the mixer 100 includes both twister plates 120 inside the inner tube 104, as well as the helical baffle plates 114, as shown in
[0028] The mixer 100 can be installed in various locations and orientations depending on design factors and available mechanical space. For example, in
[0029] The mixer 100 can also be installed as shown in
[0030] Where mechanical space may be limited, the mixer 100 can be installed as shown in
[0031]
[0032] In view of the above, the mixers 100 described herein have a number of benefits and advantages. For example, the mixer 100 may keep two streams separate and may form a flow pattern that keeps the liquid droplets in suspension and enables full vaporization before the droplets contact a solid surface. Further, the two streams may intentionally not be fully mixed prior to exiting the mixing device, and instead the high temperature of the convection section wall is exploited to create a boundary layer of diluent that is rapidly heated to a high temperature. Such an arrangement essentially exploits the Leidenfrost effect since the diluent is heated to a high temperature at the tube inner wall and vaporization of droplets within the mixed fluid stream is strongly favored over vaporization of droplets at the tube wall.
[0033] Further, the distribution of concentration and temperature may not be constant in the mixer, in order to favor vaporization of droplets in the main flow as opposed to at the heated surface downstream of the mixing device. In some embodiments, the two streams may only be mixed at the exit of the device once the flow is fully formed to improve vaporization.
[0034] In some embodiments, the mixers of the present disclosure mix two streams: one gaseous and the other containing liquid or liquid droplets. At the mixing point, the liquid or liquid droplets may get vaporized. During the vaporization process, any heavy components in the liquid may foul the mechanical surface, such as the internal surface of the carrying tube, vessel or the mixer components. The mixers of the disclosure include two co-axial pipes that keep the two streams separate before mixing. The non-fouling stream flows in the outer pipe and the fouling-possible stream flows in the inner pipe. Between the inner and outer pipes, the mixer may include helical baffles that will create twisted flows in the non-fouling stream before exiting the co-axial pipe section. The twisted flow will form a boundary layer that may prevent or minimize the stream with liquid and/or liquid droplets from contacting the piping surface. The liquid droplets will gradually mix with the stream near the tube surface and become vaporized to minimize the possibility of liquid contacting with the tube surface that may lead to fouling.
[0035] In an embodiment, a mixer includes: an outer tube; a nozzle in communication with the outer tube; an inner tube inside the outer tube and having an inlet, the inner tube operable to receive a hydrocarbon stream through the inlet and convey the hydrocarbon stream along a flow path through the inner tube from the inlet to an outlet of the inner tube; a space between the inner tube and the outer tube, the outer tube 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 operable to generate a twisted diluent flow from the diluent stream, wherein the twisted diluent flow and the hydrocarbon stream are mixed downstream of the outlet of the inner tube with the twisted diluent flow forming a boundary layer along an internal surface of the outer tube.
[0036] In an embodiment, the inner tube is arranged coaxially with respect to the outer tube, the inner tube having a length that is less than a length of the outer tube, the boundary layer operable to prevent or minimize liquid in the hydrocarbon stream from contacting an internal surface of the outer tube.
[0037] In an 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 relative a flow axis through the inner tube between and including 30 degrees and 45 degrees.
[0038] In an embodiment, the inner tube includes at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.
[0039] In an embodiment, the at least one baffle is a helical baffle on an exterior surface of the inner tube.
[0040] In an embodiment, the boundary layer is operable to prevent or minimize liquid in the hydrocarbon stream from contacting an internal surface of the outer tube.
[0041] In an embodiment, a mixer includes: an outer tube; an inner tube inside the outer tube and arranged coaxially with respect 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 along a flow path through the inner tube from the inlet to an outlet of the inner tube positioned inside the outer tube; and a space between the inner tube and the outer tube, the outer tube 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 with the diluent stream forming a boundary layer along an internal surface of the outer tube to prevent or minimize liquid or liquid droplets from the hydrocarbon stream from contacting the internal surface of the outer tube.
[0042] In an embodiment, the mixer further includes 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 operable to generate a twisted diluent flow from the diluent stream, wherein the twisted diluent flow forms the boundary layer.
[0043] In an 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 relative a flow axis through the inner tube between and including 30 degrees and 45 degrees.
[0044] In an embodiment, the inner tube includes at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.
[0045] In an embodiment, a direction of rotation of the twisted diluent flow is the same as a direction of rotation of the twisted hydrocarbon flow.
[0046] In an embodiment, a direction of rotation of the twisted diluent flow is opposite a direction of rotation of the twisted hydrocarbon flow.
[0047] In an embodiment, the inner tube includes at least one twister plate operable to generate a twisted hydrocarbon flow from the hydrocarbon stream.
[0048] In an embodiment, a mixer includes: an outer tube; an inner tube arranged within 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 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 with the diluent stream configured to produce a boundary layer along an internal surface of the outer tube to prevent or minimize liquid or liquid droplets from the hydrocarbon stream from contacting the internal surface of the outer tube.
[0049] In an embodiment, the inner tube includes at least one baffle on an outer surface of the inner tube, the at least one baffle operable to generate a twisted diluent flow from the diluent stream that produces the boundary layer.
[0050] In an embodiment, the at least one baffle is arranged on the outer surface of the inner tube at an angle relative to a flow axis through the inner tube between and including 30 degrees and 45 degrees.
[0051] In an embodiment, the inner tube includes at least one twister plate.
[0052] In an embodiment, the inner tube includes at least one twister plate internal to the inner tube operable to produce a twisted hydrocarbon flow and at least one baffle external to the inner tube operable to produce a twisted diluent flow that produces the boundary layer.
[0053] In an embodiment, the inner tube is arranged coaxially with respect to the outer tube.
[0054] In an embodiment, a portion of a length of the inner tube is received within the outer tube, and the inner tube further includes a flow control device being at least one baffle or at least one twister plate, the flow control device extending along less than an entirety of the portion of the length of the inner tube.
[0055] In the above description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the disclosure. However, one skilled in the art will understand that the disclosure may be practiced without these specific details. In other instances, well-known structures associated with the technology have not been described in detail to avoid unnecessarily obscuring the descriptions of the embodiments of the present disclosure.
[0056] Certain words and phrases used in the specification are set forth as follows. As used throughout this document, including the claims, the singular form a, an, and the include plural references unless indicated otherwise. Any of the features and elements described herein may be singular, e.g., a shell may refer to one shell. The terms include and comprise, as well as derivatives thereof, mean inclusion without limitation.
[0057] The use of ordinals such as first, second, third, etc., does not necessarily imply a ranked sense of order, but rather may only distinguish between multiple instances of an act or a similar structure or material.
[0058] Throughout the specification, claims, and drawings, the following terms take the meaning explicitly associated herein, unless the context clearly dictates otherwise. The term herein refers to the specification, claims, and drawings associated with the current application. The phrases in one embodiment, in another embodiment, in various embodiments, in some embodiments, in other embodiments, and other derivatives thereof 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 similarly treated.
[0059] The terms top, bottom, upper, lower, up, down, above, below, left, right, and other like derivatives take their common meaning as directions or positional indicators, such as, for example, gravity pulls objects down and left refers to a direction that is to the west when facing north in a Cardinal direction scheme. These terms are not limiting with respect to the possible orientations explicitly disclosed, implicitly disclosed, or inherently disclosed in the present disclosure and unless the context clearly dictates otherwise, any of the aspects of the embodiments of the disclosure can be arranged in any orientation.
[0060] Unless the context clearly dictates otherwise, relative terms such as approximately, substantially, and other derivatives, are construed to include an ordinary error range or manufacturing tolerance due to slight 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 that is within plus or minus 5% of the stated value, amount, quantity, or dimension. It is to be further understood that any specific dimensions of components or features provided herein are for illustrative purposes only with reference to the various embodiments described herein, and as such, it is expressly contemplated in the present disclosure to include dimensions that are more or less than the dimensions stated, unless the context clearly dictates otherwise. All ranges of dimensions or other values include all possible intervening and limit values, unless the context clearly dictates otherwise.
[0061] The present application claims priority to U.S. Provisional Application No. 63/351,755, filed Jun. 13, 2022 in the United States Patent and Trademark Office, the entire contents of which are incorporated herein by reference.
[0062] 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 the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the breadth and scope of a disclosed embodiment 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.