High viscosity heavy oil heat exchange device based on spin current twist tube

Abstract

This invention discloses a high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube, comprising a shell, tube-side inlet and outlet, and shell-side inlet and outlet; a heat exchange tube bundle connected between the tube-side inlet and outlet, the heat exchange tube bundle being composed of multiple U-shaped spin-flow tortuous tubes arranged side by side; each spin-flow tortuous tube includes a tortuous tube inlet, a spiral guide rib, a tortuous tube outlet, and a vibration-damping support ring, the spiral guide rib being disposed on the inner wall of the vibration-damping support ring, the pitch of the spiral guide rib increasing linearly along the heavy oil flow direction; multiple baffles are uniformly arranged circumferentially on the heat exchange tube bundle, each baffle having multiple tube holes, the spin-flow tortuous tubes passing through the tube holes of the baffles and fitting with the clearance; an online cleaning device is installed on the shell, the online cleaning device monitoring the scaling condition through an acoustic wave monitor, and the control unit controlling a pulse generator to emit pulse waves to clean the scaling. This invention can achieve efficient and stable heat exchange of high-viscosity heavy oil under low energy consumption conditions, while simultaneously solving the performance degradation problem caused by scaling through an intelligent cleaning system.

Description

Technical Field

[0001] This invention relates to the field of heat exchange equipment technology, and specifically to a high-viscosity heavy oil heat exchange device based on a spin-flow twisted tube. Background Technology

[0002] Shell-and-tube heat exchangers are core heat exchange equipment in industries such as petrochemicals and energy power, and are widely used in the heat exchange process of high-viscosity heavy oil. However, due to its high viscosity, poor fluidity, and tendency to scale, high-viscosity heavy oil tends to form a laminar flow state when flowing in traditional smooth tube heat exchangers, resulting in a low heat transfer coefficient and difficulty in improving heat exchange efficiency. At the same time, components such as gums and asphaltenes in heavy oil are prone to precipitate and form scale on the tube walls when the temperature changes, which further increases the thermal resistance and causes a sharp deterioration in heat exchange performance. In existing technologies, methods such as increasing the heat exchange area, increasing the flow rate, or periodic shutdown for cleaning all suffer from problems such as large equipment size, high energy consumption, and impact on production continuity. Ordinary enhanced heat transfer tubes still face limitations such as easy clogging and difficult cleaning. Therefore, it is necessary to develop a heat exchange device that can achieve low-energy and high-efficiency heat dissipation, and can achieve online tube wall cleaning to avoid high thermal resistance caused by tube wall scaling, specifically targeting the characteristics of high-viscosity heavy oil. Summary of the Invention

[0003] To address the technical challenges of low heat transfer efficiency, easy scaling, high energy consumption, and difficult cleaning of high-viscosity heavy oil, and to improve the heat transfer performance, operational stability, and cleaning efficiency of heat exchange equipment, this invention provides a high-viscosity heavy oil heat exchange device based on a swirl-flow twisted tube.

[0004] The technical solution of this application is as follows:

[0005] A high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube includes a shell, a tube-side inlet connected to the shell, a tube-side outlet, a shell-side inlet, and a shell-side outlet. A heat exchange tube bundle connects the tube-side inlet and the tube-side outlet, and the heat exchange tube bundle consists of multiple U-shaped spin-flow tortuous tubes arranged side-by-side. Each spin-flow tortuous tube includes a tortuous tube inlet, a spiral guide rib, a tortuous tube outlet, and a vibration-damping support ring. The spin-flow tortuous tube is a one-piece molded structure, and the spiral guide rib is disposed on the inner wall of the vibration-damping support ring. The spiral guide rib extends along... The pitch of the heavy oil flow increases linearly; the inlet and outlet of the swirl-flow twisted tube are connected to the tube sheet; multiple baffles are evenly arranged circumferentially on the heat exchange tube bundle, and multiple tube holes are correspondingly arranged on the baffles; the swirl-flow twisted tube passes through the tube holes of the baffles and is clearance-fitted with the baffles; an online cleaning device is installed on the shell, which monitors the scaling inside the swirl-flow twisted tube through an acoustic wave monitor, and controls a pulse generator to emit pulse waves to clean the scaling inside the swirl-flow twisted tube through a control unit.

[0006] This invention, based on the principle of fluid boundary layer control, utilizes a swirl-flow tortuous tube structure with continuous spiral guide ribs on its inner wall to force the generation of a rotating secondary flow when high-viscosity heavy oil flows through it. This effectively disrupts the thermal boundary layer and significantly improves heat transfer efficiency. The pitch of the spiral guide ribs increases progressively along the heavy oil flow direction, with a smaller pitch at the tortuous tube inlet to enhance the rotation intensity of the heavy oil and a larger pitch at the outlet to reduce flow resistance, achieving a balance between heat transfer efficiency and pressure drop loss. The invention employs a synergistic design of a vibration-resistant support ring and a baffle plate with a clearance fit, ensuring the freedom of thermal expansion of the swirl-flow tortuous tube while suppressing its vibration, thus extending the equipment's service life. An online cleaning device is incorporated, using an acoustic monitor to detect the scaling status of the tube bundle in real time and a pulse generator to intelligently adjust the cleaning intensity and frequency, dynamically maintaining efficient heat exchanger operation. This invention enables efficient and stable heat exchange of high-viscosity heavy oil under low-energy conditions, while simultaneously addressing performance degradation caused by scaling through an intelligent cleaning system.

[0007] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube, the pitch of the spiral guide ribs at the inlet of the twisted tube is 25-35 mm; and the pitch at the outlet of the twisted tube is 45-55 mm. This design effectively forces the generation of a rotating secondary flow when high-viscosity heavy oil flows through it.

[0008] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube, the height of the arc-shaped baffle notch is 15%-35% of the shell diameter. The height of the arc-shaped baffle notch refers to the height of the flow window when the shell-side heat exchange medium passes through the baffle. This height design can achieve a balance between shell-side flow resistance and heat transfer coefficient, avoiding situations where the notch is too small and the resistance is too high, or too large and the heat transfer is insufficient.

[0009] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube, the gap between the vibration-damping support ring and the baffle tube hole is 0.5mm-1.5mm. Controlling the gap between the vibration-damping support ring and the baffle tube hole to 0.5mm-1.5mm suppresses vibration of the spin-flow tortuous tube while ensuring the freedom of thermal expansion of the tube.

[0010] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube, the shell includes a front tube box, a shell body, and a rear tube box; the tube sheet is welded and fixedly connected to the shell body. This welded and fixed connection makes the tube sheet more stable during device operation, thereby ensuring greater stability of the spin-flow tortuous tube connected to the tube sheet.

[0011] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube, the baffle plate is connected and fixed by a support rod. The support rod can further stabilize the baffle plate, preventing it from shaking during the flow and scouring of the heat exchange medium in the shell side, thereby preventing instability of the spin-flow tortuous tube.

[0012] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube, the acoustic wave monitor is arranged in a multi-sensor array, including a piezoelectric ceramic sensor, a signal conditioning module, and a feature extraction unit; the pulse frequency of the pulse generator is 1-10Hz. In this invention, the piezoelectric ceramic sensor adopts a broadband resonant design with a resonant frequency of 50kHz and a frequency response range of 20kHz-100kHz. It is uniformly distributed at key monitoring points on the housing using magnetic clamps. The signal conditioning module has a built-in preamplifier and high-pass filter, and the gain can be intelligently adjusted within the range of 60-80dB to effectively suppress low-frequency mechanical vibration interference. The feature extraction unit, based on digital signal processing technology, analyzes the attenuation coefficient, spectral energy distribution, and propagation delay characteristics of the acoustic signal in real time to establish a mapping relationship model between acoustic feature parameters and scale thickness. The working pressure of the pulse generator is linked to the acoustic monitoring results, and the pressure adjustment range is 0.5-2.0MPa. The control unit calculates the degree of scaling in real time based on the acoustic feature parameters. When the feature parameters exceed the set threshold, the cleaning program is automatically triggered, and the pulse frequency and action time are dynamically adjusted based on the scaling distribution characteristics.

[0013] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube, a saddle-type support is provided at the bottom of the casing. The saddle-type support is used to support and fix the entire unit.

[0014] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a swirl-flow tortuous tube, the inner diameter of the swirl-flow tortuous tube is 25-30 mm. This inner diameter setting allows the heavy oil to have good flowability, avoiding clogging caused by too small a tube diameter, and also avoiding the problem of low heat exchange efficiency caused by too large a tube diameter.

[0015] Preferably, in the aforementioned high-viscosity heavy oil heat exchanger based on a spin-flow tortuous tube, the height of the spiral guide rib is 2.5-3.5 mm. The height of the spiral guide rib refers to the radial height of the spiral guide rib protruding from the inner wall of the spin-flow tortuous tube. After protruding from the inner wall, the spiral guide rib can guide and disturb the high-viscosity heavy oil flowing through the spin-flow tortuous tube, causing the heavy oil to form a rotating secondary flow, disrupting the thermal boundary layer near the tube wall, thereby improving heat exchange efficiency. If the height of the spiral guide rib is too low, the disturbance and swirl-inducing effect on the heavy oil will be insufficient; if the height is too high, it will significantly reduce the effective flow cross-sectional area inside the tube, leading to increased flow resistance and pressure drop, and even increasing the risk of blockage.

[0016] In summary, the beneficial effects of this invention are reflected in:

[0017] (1) Based on the principle of enhanced heat transfer by swirling flow, a unique spin flow tortuous tube structure design is used to actively generate a rotating secondary flow during the flow of high viscosity medium, which effectively destroys the thermal boundary layer and significantly improves the heat transfer efficiency.

[0018] (2) Set up an intelligent online cleaning system, use acoustic monitoring technology to sense the scaling status of the equipment in real time, and use adaptive pulse cleaning technology to dynamically maintain the cleanliness of the heat exchange surface, so as to ensure the long-term stable operation of the equipment;

[0019] (3) The design of vibration-resistant support and flow field optimization is adopted to optimize the shell-side medium distribution while ensuring the structural stability of the equipment, effectively suppressing vibration and eliminating flow dead zones, and comprehensively improving the reliability of equipment operation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the high-viscosity heavy oil heat exchange device based on a spin-flow twisted tube according to the present invention.

[0021] Figure 2 This is the present invention. Figure 1 Schematic diagram of section AA.

[0022] Figure 3 This is the present invention. Figure 1 Schematic diagram of the CC section.

[0023] Figure 4 This is a schematic diagram of the internal structure of the housing of the present invention and a partially enlarged view.

[0024] Figure 5 This is a schematic diagram of the cross-sectional structure of the spin flow tortuous tube of the present invention.

[0025] Figure 6 This is a schematic diagram of the principle structure of the online cleaning device system of the present invention.

[0026] The labels in the attached diagram are as follows: 1-Shell; 101-Front-end tube box; 102-Shell cylinder; 103-Rear-end tube box; 2-Tube-side inlet; 3-Tube-side outlet; 4-Shell-side inlet; 5-Shell-side outlet; 6-Spinning tortuous tube; 601-Turned tube inlet; 602-Turned tube outlet; 603-Helical guide rib; 604-Vibration-resistant support ring; 7-Baffle plate; 701-Arch-shaped baffle plate notch; 8-Support rod; 9-Tube sheet; 10-Support base; 11-Online cleaning device; 111-Pulse generator; 112-Acoustic wave monitor; 1121-Piezoelectric ceramic sensor; 1122-Signal conditioning module; 1123-Feature extraction unit; 113-Control unit. Detailed Implementation

[0027] The technical solution of the present invention will be further described in detail below through specific embodiments and with reference to the accompanying drawings, but this should not be construed as limiting the present invention. Contents not described in detail in the following embodiments are all common knowledge in the art or can be implemented using conventional technical means in the art.

[0028] Reference to embodiments of the present invention Figures 1-6 .

[0029] A high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube includes a shell 1, which is cylindrical in shape and comprises a front tube box 101, a shell body 102, and a rear tube box 103. The front tube box 101 is a common pressure vessel head found in the market. A pressure gauge interface is located on the right side of the front tube box 101, an exhaust valve is located at the top, and a maintenance manhole is located in the middle. The pressure gauge interface, exhaust valve, and maintenance manhole are standard features in this field. The inner wall of the shell body 102 has a baffle positioning groove along its circumference. A safety valve interface is located at the top of the shell body 102, a support base 10 is located at the bottom, and an anti-impact baffle is located at the rear of the shell body 102. The anti-impact baffle has an inspection hole for observing the internal condition of the shell 1. The safety valve interface, anti-impact baffle, and inspection hole are standard features in this field. The shell body 102 is made of low-alloy steel, and its front end is fixedly connected to the tube sheet 9 by welding. The rear end pipe box 103 is generally ellipsoidal and made of low alloy steel. The rear end pipe box 103 is fixedly connected to the shell body 102 through a flange.

[0030] The outer side of the shell 1 is provided with a tube-side inlet 2, a tube-side outlet 3, a shell-side inlet 4, and a shell-side outlet 5. The tube-side outlet 3 and tube-side inlet 2 are respectively located on the upper and lower sides of the shell 1; the shell-side outlet 5 and shell-side inlet 4 are respectively located on the upper and lower sides of the shell 1. Multiple U-shaped swirl-flow twisted tubes 6 are connected between the tube-side inlet 2 and tube-side outlet 3. These multiple swirl-flow twisted tubes 6 are arranged side-by-side to form a heat exchange tube bundle. The heat exchange tube bundle is used to realize heat transfer between heavy oil and the heat exchange medium. In this invention, the tube side is used to transport heavy oil, and the shell side is used to transport the heat exchange medium. Two sets of baffles 7 are evenly arranged along the circumference of the heat exchange tube bundle. One set of baffles 7 is embedded and fixed in the baffle positioning groove on the upper inner side of the shell 1, and the other set of baffles 7 is embedded and fixed in the baffle positioning groove on the lower inner side of the shell 1. The baffles 7 have evenly distributed tube holes to pass through the multiple swirl-flow twisted tubes 6. The height H of the arc-shaped baffle notch 701 of the baffle 7 is 25% of the diameter of the shell 1. The baffle 7 is used to change the flow direction of the heat exchange medium in the shell side, prolong the heat exchange time, and improve the heat exchange efficiency. The baffle 7 is connected and fixed by the support rod 8.

[0031] The U-shaped swirl flow tortuous tube 6 is a one-piece molded structure. In this embodiment, the inner diameter of the swirl flow tortuous tube 6 is 28mm. The swirl flow tortuous tube 6 includes a tortuous tube inlet 601, a tortuous tube outlet 602, and a vibration-damping support ring 604. A spiral guide rib 603 is provided on the inner wall of the vibration-damping support ring 604 between the tortuous tube inlet 601 and the tortuous tube outlet 602. In this embodiment, the height of the spiral guide rib 603 is 3mm. The tortuous tube inlet 601 and the tortuous tube outlet 602 are fixedly connected to the tube sheet 9 by expansion joint. The pitch of the spiral guide rib 603 increases gradually along the direction of heavy oil flow. In this embodiment, the pitch of the spiral guide rib 603 is 30mm at the inlet and 50mm at the outlet. The smaller pitch at the tortuous tube inlet 601 enhances the rotation intensity of the heavy oil, while the larger pitch at the tortuous tube outlet 602 reduces the flow resistance of the heavy oil, achieving a balance between heat transfer efficiency and pressure drop loss. The outer side of the vibration-damping support ring 604 forms a clearance fit with the tube hole of the baffle plate 7, which can effectively suppress the vibration of the spin flow tortuous tube 6 induced by heavy oil flow. In this embodiment, the gap between the vibration-damping support ring 604 and the tube hole of the baffle plate 7 is 1mm. While suppressing the vibration of the spin flow tortuous tube 6, it can ensure the degree of freedom of thermal expansion of the spin flow tortuous tube 6.

[0032] An online cleaning device 11 is installed on the outer side of the housing 1. The online cleaning device 11 includes an acoustic wave monitor 112, a pulse generator 111, and a control unit 113. The acoustic wave monitor 112 adopts a multi-sensor array arrangement, including a piezoelectric ceramic sensor 1121, a signal conditioning module 1122, and a feature extraction unit 1123. The piezoelectric ceramic sensor 1121 adopts a broadband resonant design with a resonant frequency of 50kHz and a frequency response range of 20kHz-100kHz. It is evenly distributed at key monitoring points of the housing 1 by magnetic clamps. The signal conditioning module 1122 has a built-in preamplifier and a high-pass filter to enhance the signal strength. The pressure can be intelligently adjusted within the range of 60-80dB to effectively suppress low-frequency mechanical vibration interference. The feature extraction unit 1123, based on digital signal processing technology, analyzes the attenuation coefficient, spectral energy distribution, and propagation delay characteristics of the acoustic signal in real time, and establishes a mapping relationship model between acoustic characteristic parameters and scale thickness. The working pressure of the pulse generator 111 is linked to the acoustic monitoring results, and the pressure adjustment range is 0.5-2.0MPa. The control unit 112 calculates the degree of scaling in real time according to the acoustic characteristic parameters. When the characteristic parameters exceed the set threshold, the cleaning program is automatically triggered, and the pulse frequency and action time are dynamically adjusted based on the scaling distribution characteristics. In this embodiment, the pulse frequency of the pulse generator 111 is 1-10Hz.

[0033] The working process of this invention:

[0034] (1) During the heat exchange process start-up stage, high viscosity heavy oil enters the heat exchange device through the tube side inlet 2. After the heavy oil enters the spin flow twisted tube 6, it generates a strong rotating secondary flow under the guidance of the spiral guide rib 603. This rotating flow continuously destroys the thermal boundary layer at the tube wall of the spin flow twisted tube 6, significantly enhances the tube side heat transfer efficiency, and effectively inhibits the deposition of pollutants on the tube wall.

[0035] (2) The shell-side heat exchange medium enters the shell 1 of the heat exchange device from the shell-side inlet 4. Under the guidance of the baffle 7, it repeatedly scours the outer wall of the spin flow tortuous tube 6 laterally at a set flow rate and direction. The shell-side fluid forms sufficient turbulence through the optimized design of the notch height, thereby achieving shell-side heat transfer enhancement.

[0036] (3) During operation, the acoustic wave monitor 112 works continuously. Its piezoelectric ceramic sensor 1121 collects broadband acoustic wave signals through the heat exchanger shell 1. By analyzing the attenuation characteristics and spectrum changes of the acoustic wave signals, the scale state and distribution of the spin flow twisted tube 6 are monitored and diagnosed in real time.

[0037] (4) When the control unit 113 determines that the degree of scaling has reached the preset threshold based on the acoustic monitoring data, the online cleaning program is automatically started. The pulse generator 111 adjusts the working pressure and pulse frequency according to the scaling characteristics to generate a series of high-pressure pulse jets that penetrate the gap of the heat exchange tube bundle and effectively remove the scaling on the tube wall of the swirl flow tortuous tube 6. During the cleaning process, the control unit 113 dynamically optimizes the cleaning parameters of the pulse generator 111 based on the real-time data fed back by the acoustic monitor 112 to achieve adaptive and precise cleaning for different degrees of scaling, ensuring the cleaning effect while avoiding energy waste.

[0038] (5) During the entire operation, the vibration-resistant support ring 604 continuously constrains the swirl flow tortuous tube 6 through a precise clearance fit with the tube hole of the baffle plate 7, effectively suppressing the vibration induced by the heavy oil fluid and ensuring the structural integrity and reliability of the heat exchange device during long-term operation.

[0039] (6) Finally, the heavy oil and shell heat exchange medium that have completed the heat exchange are smoothly discharged from the heat exchange device through the tube outlet and shell outlet, respectively, thus completing the entire efficient and stable heat exchange process.

[0040] The foregoing general description of the invention and its specific embodiments should not be construed as a limitation on the technical solution of the invention. Those skilled in the art, based on the disclosure of this application, can add, reduce, or combine the disclosed technical features in the foregoing general description and / or specific embodiments (including examples) without departing from the constituent elements of the invention, to form other technical solutions within the scope of protection of this invention.

Claims

1. A high-viscosity heavy oil heat exchanger based on spin current twist tube, comprising a shell (1), a tube passage inlet (2), a tube passage outlet (3), a shell passage inlet (4), and a shell passage outlet (5) connected to the shell (1); characterized in that: A heat exchange tube bundle is connected between the tube inlet (2) and the tube outlet (3). The heat exchange tube bundle is composed of multiple U-shaped swirl-flow twisted tubes (6) arranged side by side. The swirl-flow twisted tube (6) includes a twisted tube inlet (601), a spiral guide rib (603), a twisted tube outlet (602), and a vibration-damping support ring (604). The swirl-flow twisted tube (6) is an integrally formed structure. The spiral guide rib (603) is set on the inner wall of the vibration-damping support ring (604). The pitch of the spiral guide rib (603) increases linearly along the direction of heavy oil flow. The twisted tube inlet (601) of the swirl-flow twisted tube (6) is... 01) and the outlet (602) of the twisted tube are connected to the tube sheet (9); the heat exchange tube bundle is uniformly arranged with multiple baffles (7) along the circumference, and multiple tube holes are correspondingly arranged on the baffles (7). The swirl flow twisted tube (6) passes through the tube hole of the baffle (7) and is clearance-fitted with the baffle (7); an online cleaning device (11) is installed on the shell (1). The online cleaning device (11) monitors the scaling in the swirl flow twisted tube (6) through the acoustic wave monitor (112) and controls the pulse generator (111) to emit pulse waves to clean the scaling in the swirl flow twisted tube (6) through the control unit (113).

2. The high viscosity heavy oil heat exchanger based on spin current flow twisted tube according to claim 1, characterized in that: The pitch of the spiral guide rib (603) at the inlet (601) of the twisted tube is 25-35 mm; the pitch at the outlet (602) of the twisted tube is 45-55 mm.

3. The high viscosity heavy oil heat exchanger based on spin current flow twisted tube as claimed in claim 1, wherein: The height of the bow-shaped baffle notch (701) of the baffle (7) is 15%-35% of the diameter of the shell (1).

4. The high viscosity heavy oil heat exchanger based on spin current flow twisted tube as claimed in claim 1, wherein: The gap between the vibration-resistant support ring (604) and the baffle plate (7) is 0.5mm-1.5mm.

5. The high viscosity heavy oil heat exchanger based on spin current flow twisted tube as claimed in claim 1, wherein: The shell (1) includes a front tube box (101), a shell body (102) and a rear tube box (103); the tube sheet (9) is welded and fixedly connected to the shell body (102).

6. The high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube according to claim 1, characterized in that: The baffle plate (7) is connected and fixed by a support rod (8).

7. The high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube according to claim 1, characterized in that: The acoustic wave monitor (112) is arranged with a multi-sensor array, including a piezoelectric ceramic sensor (1121), a signal conditioning module (1122), and a feature extraction unit (1123); the pulse frequency of the pulse generator (111) is 1-10Hz.

8. The high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube according to claim 1, characterized in that: The bottom of the housing (1) is provided with a saddle support (10).

9. The high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube according to claim 1, characterized in that: The inner diameter of the spin flow twisted tube (6) is 25-30 mm.

10. The high-viscosity heavy oil heat exchanger based on a spin-flow twisted tube according to claim 1, characterized in that: The height of the spiral guide rib (603) is 2.5-3.5mm.

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