Double-pipe heat exchanger, anti-corrosion device of double-pipe heat exchanger, potential control method, electronic equipment and heat exchange unit

Abstract

The embodiment of the invention discloses a double-pipe heat exchanger, an anti-corrosion device of the double-pipe heat exchanger, a potential control method, electronic equipment and a heat exchange unit, and belongs to the field of heat exchangers. The potential control method comprises the following steps: acquiring the electrode potential of the inner tube after the input voltage of the flexible anode is cut off; potential control processing is selectively performed according to whether the electrode potential is in a protection potential interval. By adopting the embodiment of the invention, the uniformity of cathode protection current can be improved, the electrode potential can be quickly adjusted to a protection potential interval, and the cathode protection effect is improved.

Description

Technical Field

[0001] The present application relates to the field of heat exchangers, and in particular to a shell-and-tube heat exchanger and an anti-corrosion device thereof, a potential control method, an electronic device and a heat exchange unit. Background Art

[0002] In order to effectively protect the shell and tube heat exchanger, reduce or avoid the risk of corrosion perforation, and ensure the long-term safe operation of the shell and tube heat exchanger, appropriate anti-corrosion measures need to be taken. Cathodic protection is to connect the anode to the positive pole of the power supply, and the protected metal as the cathode to the negative pole of the power supply. A current will be formed between the anode and the cathode. When the power is turned on, the anode loses electrons as the positive pole, and the protected metal gains electrons as the negative pole. This impressed current cathodic protection current can effectively compensate for the corrosion caused by coating defects.

[0003] However, it is difficult for the existing shell and tube heat exchanger to keep the electrode potential in the shell and tube heat exchanger in the optimal potential protection range, and the protection effect is poor. Summary of the invention

[0004] The embodiments of the present application provide a shell and tube heat exchanger and an anti-corrosion device thereof, a potential control method, an electronic device and a heat exchange unit, so as to at least solve the technical problem of poor cathodic protection effect in the shell and tube heat exchanger.

[0005] According to a first aspect of an embodiment of the present application, an anti-corrosion device for a shell and tube heat exchanger is provided. The shell and tube heat exchanger comprises an inner tube and an outer tube sleeved outside the inner tube. The anti-corrosion device comprises:

[0006] A flexible anode extending into the inner tube of the shell and tube heat exchanger and matching the length and shape of the inner tube, the flexible anode comprising a reference electrode segment located at the water inlet end of the shell and tube heat exchanger and a current output segment extending into the shell and tube heat exchanger, the current output segment having a conductive coating, and the reference electrode segment not having a conductive coating;

[0007] A power source has a positive electrode connected to the flexible anode and a negative electrode connected to the inner tube.

[0008] In combination with the first aspect, in an optional implementation of the embodiment of the present application, the anti-corrosion device further includes:

[0009] A tripod is embedded in the inner tube and is used to fix the flexible anode in the inner tube.

[0010] In combination with the first aspect, in an optional implementation of the embodiment of the present application, the tripod is a polygon whose vertices are in contact with the inner circumferential wall of the inner tube, or the tripod is a circle whose outer periphery is in contact with the inner circumferential wall of the inner tube;

[0011] The tripod has a positioning rod extending from the edge of the tripod to the inside of the tripod, and one end of the positioning rod extending into the inside of the tripod has a fixing portion for fixing the flexible anode;

[0012] The center line of the inner tube passes through the fixing portion.

[0013] According to a second aspect of an embodiment of the present application, a potential control method for a shell and tube heat exchanger is provided, wherein the shell and tube heat exchanger has the anti-corrosion device according to the first aspect of the embodiment of the present application, and the method comprises:

[0014] When the electrode potential is not within the protection potential interval, the potential control process is performed; and / or when the electrode potential is within the protection potential interval, the potential control process is not performed.

[0015] Wherein, when the electrode potential is within the protection potential interval, the target operating time is continuously operated based on the input voltage, and the input voltage and the target operating time are recorded.

[0016] In combination with the second aspect, in an optional implementation of the embodiment of the present application, when the electrode potential is not within the protection potential interval, performing the potential control process includes:

[0017] When the electrode potential is less than the minimum value of the protection potential interval, determining the reduction amplitude of the input voltage according to the difference between the minimum value and the electrode potential, and adjusting the input voltage according to the reduction amplitude; and / or,

[0018] When the electrode potential is greater than the maximum value of the protection potential interval, the increase amplitude of the input voltage is determined according to the difference between the electrode potential and the maximum value, and the input voltage is adjusted according to the increase amplitude.

[0019] In combination with the second aspect, in an optional implementation of the embodiment of the present application, the reduction amplitude of the input voltage and the increase amplitude of the input voltage both satisfy: f(x)=δ·x,

[0020] Wherein, x represents the difference between the minimum value and the electrode potential, δ is a constant related to the parameters of the inner tube, and f(x) represents the reduction amplitude, or,

[0021] x represents the difference between the electrode potential and the maximum value, δ is a constant related to the parameters of the inner tube, and f(x) represents the increase amplitude.

[0022] In conjunction with the second aspect, in an optional implementation manner of the embodiment of the present application, the method further includes:

[0023] Determine the initial voltage value of the input voltage of the flexible anode according to the statistical data of historical input voltage and operation time; or,

[0024] The value of the input voltage before the most recent shutdown is used as the initial voltage value of the input voltage of the flexible anode.

[0025] In combination with the second aspect, in an optional implementation of the embodiment of the present application, determining the initial voltage value of the input voltage of the flexible anode according to the statistical data of the historical input voltage and the operating time includes:

[0026] The initial voltage value of the input voltage of the flexible anode is determined in the following manner: U = (U1t1+U2t2+...+Untn) / (t1+t2+...+tn);

[0027] Among them, U represents the initial voltage value of the input voltage of the flexible anode, Ui represents the i-th historical input voltage, ti represents the operating time corresponding to the i-th historical input voltage, 1≤i≤n, and i and n are both positive integers greater than 1.

[0028] In combination with the second aspect, in an optional implementation of the embodiment of the present application, the obtaining of the electrode potential of the inner tube after the input voltage of the flexible anode is powered off includes:

[0029] When it is determined that the electrode potential is not in the protection potential interval, or after the target operation time is continuously operated according to the input voltage, the electrode potential of the inner tube is obtained after the input voltage of the flexible anode is turned off.

[0030] According to a third aspect of an embodiment of the present application, there is provided an electronic device, including:

[0031] a memory for storing one or more computer instructions;

[0032] A processor is used to call and execute the computer instructions to implement the method described in the second aspect of the embodiment of the present application.

[0033] According to a fourth aspect of an embodiment of the present application, there is provided a shell and tube heat exchanger, comprising an inner tube;

[0034] An outer tube sleeved on the outer side of the inner tube;

[0035] And an anti-corrosion device provided according to the first aspect of an embodiment of the present application.

[0036] According to a fifth aspect of an embodiment of the present application, a heat exchange unit is provided, comprising:

[0037] A shell and tube heat exchanger, and an anti-corrosion device according to the first aspect of the embodiment of the present application; or,

[0038] The heat exchange unit includes a shell and tube heat exchanger, an anti-corrosion device provided according to the first aspect of the embodiment of the present application, and an electronic device provided according to the third aspect of the embodiment of the present application.

[0039] By adopting this embodiment, the uniformity of the cathodic protection current and the effect of cathodic protection can be improved by using a flexible anode that extends into the inner tube of the shell-and-tube heat exchanger and matches the length and shape of the inner tube. By obtaining the electrode potential of the inner tube after the input voltage of the flexible anode is turned off, and selectively performing potential control processing according to whether the electrode potential is in the protection potential interval, it is beneficial to quickly adjust the electrode potential to the protection potential interval and improve the effect of cathodic protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the structure of a shell and tube heat exchanger;

[0041] Figure 2 A structural schematic diagram of applying the anti-corrosion device provided in an embodiment of the present application to a shell and tube heat exchanger;

[0042] Figure 3 is a schematic flow chart of a potential control method for a shell and tube heat exchanger according to an embodiment of the present application;

[0043] Figure 4 It is a flow chart of a method for rapid constant potential control of a shell and tube heat exchanger according to an embodiment of the present application.

[0044] Description of labels:

[0045] 1. Positive power pole of control board; 2. Negative power pole of control board; 3. Wire; 4. Casing body; 5. Tripod; 6. Conductivity meter; 7. Power control board; 8. Flexible anode; 9. Water inlet; 10. Water outlet; 11. Reference electrode segment; 12. Built-in chip of control board. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0047] It should be understood that the "plurality" mentioned in this article refers to two or more. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second" and so on are used to distinguish between the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the words "first", "second" and so on do not limit the quantity and execution order, and the words "first", "second" and so on do not limit certain different

[0048] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or apparatus.

[0049] A shell and tube heat exchanger is a tubular heat exchanger whose working principle mainly relies on the heat conduction between the inner and outer tubes, and the heat transfer and transfer is achieved through the flow of fluid between the inner and outer tubes. For example, a shell and tube heat exchanger is composed of two standard tubes of different sizes connected to form concentric shells, the outer one is called the shell side, and the inner one is called the tube side. This structure allows two different media to flow in the opposite direction (or in the same direction) in the shell side and the tube side to achieve the effect of heat exchange. The shell and tube heat exchanger is mainly composed of a shell (including an inner shell and an outer shell), a U-shaped elbow, a stuffing box, etc., and the tubes are generally fixed on a bracket.

[0050] In order to effectively protect the shell and tube heat exchanger, reduce or avoid the risk of corrosion perforation, and ensure the long-term safe operation of the shell and tube heat exchanger, appropriate anti-corrosion measures need to be taken. Cathodic protection is to connect the anode to the positive pole of the power supply, and the protected metal as the cathode to the negative pole of the power supply. A current will be formed between the anode and the cathode. When the power is turned on, the anode loses electrons as the positive pole, and the protected metal gains electrons as the negative pole. This impressed current cathodic protection can effectively compensate for the corrosion caused by coating defects.

[0051] However, due to the structural limitations of the existing shell and tube heat exchanger, the distribution of the cathodic protection current is not ideal, for example, the distribution of the cathodic protection current is uneven. In this regard, an embodiment of the present application provides an anti-corrosion device for a shell and tube heat exchanger to improve the uniformity of the cathodic protection current.

[0052] In addition, there is an optimal potential protection range depending on the cathode protected material. At present, copper alloy is commonly used as the cathode protected metal. When it is used as the cathode protected metal, the electrode potential is -0.5V to -0.6V (SCE) which is the optimal protection range, where SCE refers to the measured value when the reference electrode is a saturated calomel electrode. In order to ensure that the potential of the inner tube of the shell and tube heat exchanger is in the range of -0.5V to -0.6V (SCE), an embodiment of the present application provides a potential control method for a shell and tube heat exchanger.

[0053] Reference Figure 1 , is a schematic diagram of the structure of a shell and tube heat exchanger. Figure 1 The shell and tube heat exchanger comprises a shell and tube body 4, a water inlet 9 at one end (water inlet end) of the shell and tube body 4 and a water outlet 10 at the other end (water outlet end) of the shell and tube body 4. The shell and tube body 4 comprises an inner tube and an outer tube (not shown) sleeved outside the inner tube.

[0054] The embodiment of the present application provides an anti-corrosion device for a shell and tube heat exchanger, which includes a flexible anode and a power supply. The flexible anode extends into the inner tube of the shell and tube heat exchanger and matches the length and shape of the inner tube. The flexible anode includes a reference electrode segment located at the water inlet end of the shell and tube heat exchanger and a current output segment extending into the shell and tube heat exchanger, wherein the current output segment has a conductive coating, and the reference electrode segment does not have a conductive coating. The power supply has a positive electrode connected to the flexible anode and a negative electrode connected to the inner tube.

[0055] The anti-corrosion device provided in this embodiment solves the limitation that ordinary electronic anodes cannot penetrate deeply into the inner tube of the shell and tube heat exchanger through a flexible anode extending into the inner tube of the shell and tube heat exchanger and matching the length and shape of the inner tube, thereby making the distribution of cathodic protection current more uniform.

[0056] Optionally, in an implementation of this embodiment, the anti-corrosion device further includes: a bracket, embedded in the inner tube, for fixing the flexible anode in the inner tube.

[0057] The tripod is a polygon whose vertices are in contact with the inner wall of the inner tube, or a circle whose outer periphery is in contact with the inner wall of the inner tube; the tripod has a positioning rod extending from the edge of the tripod to the inside of the tripod, and one end of the positioning rod extending into the inside of the tripod has a fixing portion for fixing the flexible anode; the center line of the inner tube passes through the fixing portion. In this way, the long strip of flexible anode can be stably fixed in the center of the inner tube of the shell and tube heat exchanger by the tripod.

[0058] Illustratively, the polygon may be a triangle, a rectangle, a hexagon, or the like.

[0059] Exemplarily, the fixing portion of the positioning rod may be a hole for the flexible anode to pass through, or a rope, a clamping piece, etc. for tying the flexible anode to the positioning rod.

[0060] Optionally, in an implementation of this embodiment, the sleeve body 4 may be made of a copper-nickel alloy material.

[0061] Reference Figure 2 , is a schematic diagram of a structure in which the anti-corrosion device provided in an embodiment of the present application is applied to a shell and tube heat exchanger. Figure 2 In addition to the casing body 4, the water inlet 9 and the water outlet 10, the combined structure of the anti-corrosion device and the casing heat exchanger also has the following structure.

[0062] The flexible anode 8 extends into the inner tube of the shell-and-tube heat exchanger and matches the length and shape of the inner tube. The flexible anode 8 has a reference electrode segment 11 (such as Figure 2 The current output section (shown in the solid line) extending into the shell and tube heat exchanger Figure 2 The reference electrode segment is used as a reference electrode when the power is off; the current output segment is used to output current when the power is on. The current output segment has a conductive coating (for example, coated with a conductive metal oxide), while the reference electrode segment does not have a conductive coating.

[0063] The power control board 7 is used to control the output of the power supply (not shown). The control board power positive electrode 1 (connected to the power positive electrode) is electrically connected to the flexible anode 8 through the wire 3, and the control board power negative electrode 2 (connected to the power negative electrode) is electrically connected to the inner tube through the wire.

[0064] In this embodiment, the flexible anode 8 (except the front end) needs to be coated with a layer of conductive metal oxide. When the power is on, the coated part serves as the flexible anode to output current, and when the power is off, the uncoated part of the front end of the flexible anode serves as the reference electrode. Furthermore, based on the structure provided in this embodiment, the electrode potential value of the inner tube of the shell and tube heat exchanger can be detected, and the input voltage can be adjusted in real time according to the detected value, thereby realizing precise control of the constant potential of the cathode metal.

[0065] In addition, in this embodiment, the flexible anode 8 can also be fixed in the inner tube by the tripod 5. The tripod 5 is arranged at intervals along the extension direction of the inner tube so that the flexible anode 8 is stably fixed in the inner tube and extends inside the inner tube along the extension direction of the inner tube so that the flexible anode 8 matches the length and shape of the inner tube.

[0066] In addition, in this embodiment, a conductivity meter 6 can also be provided. The conductivity of the electrolyte is collected by the conductivity meter 6 (for example, a portable conductivity meter). In cathodic protection, the conductivity of the electrolyte will affect the electrode potential of the cathode metal. The water quality and conductivity vary greatly in different places, but in the same place, unless the sampling point is changed or there is more extreme weather, the conductivity of the water body will not change much.

[0067] In addition, in this embodiment, a control board built-in chip 12 may be provided to store data, for example, to store historical input voltages and corresponding operating times. The control board built-in chip 12 may also be used to execute the potential control method mentioned below.

[0068] Figure 3 1 is a schematic flow chart of a potential control method for a shell and tube heat exchanger according to an embodiment of the present application, wherein the shell and tube heat exchanger has the anti-corrosion device provided in the foregoing text of the present application. Figure 3 As shown, the potential control method includes the following processing.

[0069] S300: Acquire the electrode potential of the inner tube after the input voltage of the flexible anode is turned off.

[0070] For example, after water is passed through the shell-and-tube heat exchanger, the flexible anode is powered on at an initial voltage value, and then the power is turned off and the electrode potential of the inner tube is collected.

[0071] S302: Selectively perform potential control processing according to whether the electrode potential is in a protection potential interval.

[0072] As mentioned above, there is an optimal potential protection range depending on the cathode protection material. For example, copper alloy is currently a common material for shell and tube heat exchangers. When it is used as the cathode protection metal, the electrode potential is -0.5V to -0.6V (SCE) is the optimal protection range, where SCE refers to the measured value when the reference electrode is a saturated calomel electrode.

[0073] By adopting the method provided in this embodiment, the reference electrode segment of the flexible anode is used as a reference electrode to detect the electrode potential of the inner tube of the shell and tube heat exchanger in the power-off state, and potential control processing is performed according to the detection value, which is conducive to achieving precise control of the constant potential of the cathode metal.

[0074] Optionally, in an implementation manner of this embodiment, S302 includes at least one of the following situations.

[0075] Case 1: When the electrode potential is not within the protection potential interval, the potential control process is performed to control the electrode potential within the protection potential interval.

[0076] Scenario 2: When the electrode potential is in the protection potential interval, the potential control process is not performed. At this time, the target operation time can be continuously operated based on the input voltage and the input voltage and the target operation time can be recorded. When the current electrode potential is in the protection potential interval, the current input voltage and the target and retrograde time can be recorded as a historical record for subsequent reference (to be explained below).

[0077] Among them, in the case where the electrode potential is less than the minimum value of the protection potential interval, the reduction amplitude of the input voltage is determined according to the difference between the minimum value and the electrode potential, and the input voltage is adjusted according to the reduction amplitude; and / or, when the electrode potential is greater than the maximum value of the protection potential interval, the increase amplitude of the input voltage is determined according to the difference between the electrode potential and the maximum value, and the input voltage is adjusted according to the increase amplitude.

[0078] In this way, the input voltage can be adjusted according to the deviation between the real-time electrode potential and the protection potential interval, and then the electrode potential can be adjusted so that the electrode potential falls within the protection potential interval.

[0079] Among them, the reduction amplitude of the input voltage and the increase amplitude of the input voltage both satisfy: f(x) = δ·x. Here, x represents the difference between the minimum value and the electrode potential, δ is a constant related to the parameters of the inner tube, and f(x) represents the reduction amplitude, or x represents the difference between the electrode potential and the maximum value, δ is a constant related to the parameters of the inner tube, and f(x) represents the increase amplitude. For example, the value of δ is between 0.5 and 2, which is determined based on experimental data and is related to the diameter, length, material and other parameters of the inner tube of the shell and tube heat exchanger.

[0080] In this way, the voltage amplitude that needs to be adjusted can be determined relatively accurately and the input voltage can be adjusted, thereby facilitating the rapid adjustment of the protection potential of the inner tube of the shell and tube heat exchanger to the potential protection range.

[0081] Optionally, in an implementation of this embodiment, before S300, an initial voltage value of the input voltage of the flexible anode is determined in the following manner.

[0082] Method 1: Determine the initial voltage value of the input voltage of the flexible anode based on the statistical data of the historical input voltage and the operating time. For example, the initial voltage value of the input voltage of the flexible anode is determined in the following manner: U = (U1t1+U2t2+...+Untn) / (t1+t2+...+tn). Wherein, U represents the initial voltage value of the input voltage of the flexible anode, Ui represents the i-th historical input voltage, ti represents the operating time corresponding to the i-th historical input voltage, 1≤i≤n, and i and n are both positive integers greater than 1.

[0083] Method 2: The value of the input voltage before the most recent shutdown is used as the initial voltage value of the input voltage of the flexible anode. For example, if there is no historical data within a set time (eg, 24 hours), this method 2 is used.

[0084] Even if the initial voltage value determined by the above two methods cannot make the electrode potential of the inner tube within the potential protection interval, it can make the electrode potential of the inner tube as close to the potential protection interval as possible, thereby reducing the number of times the input voltage is adjusted, saving time, and quickly adjusting the electrode potential of the inner tube of the shell and tube heat exchanger to the potential protection interval.

[0085] Optionally, in an implementation of the present embodiment, when it is determined that the electrode potential is not within the protection potential interval, or after continuously running for a target operating time according to the input voltage, the electrode potential of the inner tube is obtained after the input voltage of the flexible anode is cut off.

[0086] Figure 4 1 is a flow chart of a method for rapidly controlling a constant potential of a shell-and-tube heat exchanger according to an embodiment of the present application. Figure 4 , the method includes the following processing.

[0087] The flexible anode of the shell and tube heat exchanger is powered on. Specifically, after the flexible anode is installed on the shell and tube heat exchanger, water is passed through the flexible anode, and then the flexible anode is powered on.

[0088] Based on the collected voltage Un and operating time tn (data within 24 hours, this 24-hour period is only an example, and the statistical period can be selected according to actual needs, for example, 12 hours, 18 hours, etc.), calculate the initial voltage (that is, calculate the initial voltage value of the input voltage of the flexible anode). For example, the initial voltage U = (U1t1 + U2t2 +... + Untn) / (t1 + t2 +... + tn). Where, Ui represents the i-th historical input voltage, and ti represents the operating time corresponding to the i-th historical input voltage, 1 ≤ i ≤ n, and both i and n are positive integers greater than 1. In cathodic protection, the conductivity of the electrolyte affects the electrode potential of the cathodic metal. Water quality varies greatly in different places, and the conductivity is also different. However, in the same place, unless the sampling point is changed or extreme weather occurs, the water body conductivity will not change significantly. Therefore, collecting historical voltage values as the initial voltage value when the unit starts up can reduce the number of subsequent voltage adjustments.

[0089] After powering on with the initial voltage U, power off for 40 ms to detect the electrode potential u of the inner tube of the shell-and-tube heat exchanger. That is, after powering on the flexible anode, then detect the electrode potential u of the inner tube of the shell-and-tube heat exchanger in the power-off state. Among them, 40 ms is only an example, representing the power-off duration.

[0090] Judge whether u < umin holds. If this relational expression does not hold, it indicates that there is no risk of overprotection for the shell-and-tube heat exchanger. At this time, continue to judge whether the relational expression u > umax holds. Where, umin represents the minimum value of the protection potential range, and umax represents the maximum value of the protection potential range.

[0091] If u < umin holds, it indicates that the shell-and-tube heat exchanger is overprotected, and a hydrogen evolution reaction may occur in the medium, resulting in a risk of hydrogen embrittlement for the shell-and-tube heat exchanger.

[0092] In the case of u < umin, let k = umin - u, and then control the input voltage of the flexible anode to be U = U - f(k), where f(k) = δk. The value of δ ranges from 0.5 to 2, which is specifically determined based on experimental data and is related to parameters such as the diameter, length, and material of the inner tube of the shell-and-tube heat exchanger.

[0093] Power off for 40 ms to detect the electrode potential u of the inner tube of the shell-and-tube heat exchanger.

[0094] Judge whether u ≥ umin holds at this time. If the relational expression u ≥ umin does not hold, return to the above execution step of letting k = umin - u.

[0095] If \(u\geq u_{min}\) holds, then continue to determine whether \(u > u_{max}\) holds. If the relation \(u > u_{max}\) does not hold, it indicates that the electrode potential \(u\) of the inner tube of the shell-and-tube heat exchanger is within the potential protection range of this metal material at this time, and then operate continuously for time \(t\) with the input voltage \(U\) of the flexible anode at this time.

[0096] If the relation \(u > u_{max}\) holds, it indicates that the shell-and-tube heat exchanger is in an under-protected state at this time. At this time, let \(j = u - u_{max}\), and control the input voltage of the flexible anode to be \(U = U + f(j)\), where \(f(j)=\delta j\), and detect the electrode potential \(u\) of the inner tube of the shell-and-tube heat exchanger after power-off for 40 ms.

[0097] Determine whether \(u_{min}\leq u\leq u_{max}\) is satisfied at this time. If this relation is satisfied, then operate continuously for time \(t\) with the input voltage \(U\) of the flexible anode at this time; collect the input voltage \(U_n\) and the operating time \(t_n\) of the unit, and record \(U_n\) and \(t_n\) into the chip of the flexible anode; after time \(t\), detect the electrode potential \(u\) of the inner tube of the shell-and-tube heat exchanger after power-off for 40 ms, and return to the loop to determine whether \(u_{min}\leq u\leq u_{max}\) is satisfied. Among them, \(t\) can be determined according to the change rate of water quality. After the voltage is stable, the potential is generally detected once every 5 - 10 minutes.

[0098] If \(u_{min}\leq u\leq u_{max}\) is not satisfied, then return to the execution step of determining whether \(u < u_{min}\) holds.

[0099] Adopting the above loop judgment and execution process is beneficial to quickly adjust the protection potential of the inner tube of the shell-and-tube heat exchanger to the optimal protection range.

[0100] An embodiment of the present application also provides an electronic device, which includes a memory and a processor. Among them, the memory is used to store one or more computer instructions; the processor is used to call and execute the computer instructions to implement the present application Figure 3 or Figure 4 the corresponding potential control method.

[0101] An embodiment of the present application also provides a shell-and-tube heat exchanger, which includes the anti-corrosion device provided by the embodiment of the present application, or, while including the anti-corrosion device provided by the embodiment of the present application, the shell-and-tube heat exchanger also includes the above-mentioned electronic device / employs the present application Figure 3 or Figure 4 the corresponding potential control method.

[0102] An embodiment of the present application also provides a heat exchange unit, the heat exchange unit includes a shell-and-tube heat exchanger, and the anti-corrosion device provided by the embodiment of the present application; or, the heat exchange unit includes a shell-and-tube heat exchanger, the anti-corrosion device provided by the embodiment of the present application and the electronic device provided by the embodiment of the present application.

[0103] In addition, the heat exchange unit may also include the following structures.

[0104] Pump group: Used to drive the fluid to circulate inside the casing to ensure the smooth progress of heat exchange. The selection and configuration of the pump group need to be determined according to parameters such as the properties, flow rate, and pressure of the fluid.

[0105] Control system: Used to monitor and control various parameters during the heat exchange process, such as temperature, pressure, flow rate, etc. The control system can automatically adjust the working state of the pump group to ensure the high efficiency and stability of the heat exchange process.

[0106] Auxiliary equipment: Such as filters, valves, pressure gauges, etc., used to ensure the cleanliness of the fluid, control the flow direction and flow rate of the fluid, and monitor various parameters during the heat exchange process.

[0107] Frame and support structure: Used to support and fix the shell-and-tube heat exchanger and other equipment to ensure the stability and safety of the entire unit.

[0108] Exemplarily, the shell-and-tube heat exchanger, the anti-corrosion device of the shell-and-tube heat exchanger, and the potential control method provided by the embodiments of the present application can be applied to units containing shell-and-tube heat exchangers such as household water machines and ground source heat pumps.

[0109] Generally speaking, in the flexible anode (except for the front end) provided by the related embodiments of the present application, a layer of conductive metal oxide is coated. When energized, the coated part acts as a flexible anode to output current, and when powered off, the uncoated part at the front end of the flexible anode acts as a reference electrode. By detecting the electrode potential value of the inner tube of the shell-and-tube heat exchanger and adjusting the magnitude of the input voltage U in real time according to the detected value, precise control of the constant potential of the cathode metal is achieved.

[0110] In the related embodiments of the present application, the electrode potential u of the shell-and-tube heat exchanger is detected in real time. According to the relationship between u, umin, and umax, when u < umin, the increased value of the input voltage is f(k) = δ(umin - u); when u > umax, the decreased value of the input voltage is f(j) = δ(u - umax). By comparing with different reference values and sampling feedback, the corresponding control quantity is obtained, and the amplitude of the change in the input voltage U is slowed down.

[0111] In the related embodiments of the present application, by collecting the values of the input voltage Un and the duration tn of the historical data of the unit (for example, the historical data within 24 hours), the weighted average value of Un is taken as the initial input voltage, that is, U = (U1t1 + U2t2 +... + Untn) / (t1 + t2 +... + tn). By collecting historical data, the protection potential of the inner tube of the shell-and-tube heat exchanger is quickly adjusted to the optimal protection interval.

[0112] In the above-mentioned embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments. The steps shown in the relevant flow chart can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flow chart, in some cases, the steps shown or described can be executed in an order different from that here. In other words, the order of steps described in the foregoing embodiments is only an example, and it is also within the scope of protection of the embodiments of the present application to reasonably adjust the order of steps based on the content of the embodiments of the present application.

[0113] The sequence of serial numbers or introduction of the embodiments of the present application is for description only and does not represent the superiority or inferiority of the embodiments.

[0114] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0115] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0116] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0117] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access, or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a digital versatile disc (DVD)), or a semiconductor medium (e.g., a solid state disk (SSD)). It is worth noting that the computer-readable storage medium mentioned in the embodiment of the present application may be a non-volatile storage medium, in other words, a non-transient storage medium.

[0118] It should be noted that the information (including but not limited to user device information, user personal information, etc.), data (including but not limited to data for analysis, stored data, displayed data, etc.) and signals involved in the embodiments of this application are all authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions. For example, the scene data of the current frame in the three-dimensional virtual scene, the device information of the client, and the scene interaction information involved in the embodiments of this application are all obtained with full authorization.

[0119] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A corrosion protection device for a shell and tube heat exchanger, the shell and tube heat exchanger comprising an inner tube and an outer tube sleeved outside the inner tube, characterized in that: The anti-corrosion device comprises: A flexible anode extending into the inner tube of the shell and tube heat exchanger and matching the length and shape of the inner tube, the flexible anode comprising a reference electrode segment located at the water inlet end of the shell and tube heat exchanger and a current output segment extending into the shell and tube heat exchanger, the current output segment having a conductive coating, and the reference electrode segment not having a conductive coating; A power source has a positive electrode connected to the flexible anode and a negative electrode connected to the inner tube.

2. The anti-corrosion device according to claim 1, characterized in that: The anti-corrosion device also includes: A tripod is embedded in the inner tube and is used to fix the flexible anode in the inner tube.

3. The anti-corrosion device according to claim 2, characterized in that: The tripod is a polygon whose vertices are in contact with the inner wall of the inner tube, or the tripod is a circle whose outer periphery is in contact with the inner wall of the inner tube; The tripod has a positioning rod extending from the edge of the tripod to the inside of the tripod, and one end of the positioning rod extending into the inside of the tripod has a fixing portion for fixing the flexible anode; The center line of the inner tube passes through the fixing portion.

4. A method for controlling potential of a shell and tube heat exchanger, wherein the shell and tube heat exchanger has an anti-corrosion device according to any one of claims 1 to 3, the method comprising: acquiring the electrode potential of the inner tube after the input voltage of the flexible anode is turned off; The potential control process is selectively performed according to whether the electrode potential is in the protection potential interval.

5. The potential control method according to claim 4, characterized in that: The selectively performing potential control processing according to whether the electrode potential is in the protection potential interval includes: When the electrode potential is not within the protection potential interval, the potential control process is performed; and / or when the electrode potential is within the protection potential interval, the potential control process is not performed.

6. The potential control method according to claim 5, characterized in that: The method further comprises: When the electrode potential is within the protection potential interval, the target operation time is continuously operated based on the input voltage, and the input voltage and the target operation time are recorded.

7. The potential control method according to claim 5, characterized in that: When the electrode potential is not within the protection potential interval, performing the potential control process includes: When the electrode potential is less than the minimum value of the protection potential interval, determining the reduction amplitude of the input voltage according to the difference between the minimum value and the electrode potential, and adjusting the input voltage according to the reduction amplitude; and / or, When the electrode potential is greater than the maximum value of the protection potential interval, the increase amplitude of the input voltage is determined according to the difference between the electrode potential and the maximum value, and the input voltage is adjusted according to the increase amplitude.

8. The potential control method according to claim 7, characterized in that: The reduction amplitude of the input voltage and the increase amplitude of the input voltage both satisfy: f(x)=δ·x, Wherein, x represents the difference between the minimum value and the electrode potential, δ is a constant related to the parameters of the inner tube, and f(x) represents the reduction amplitude, or, x represents the difference between the electrode potential and the maximum value, δ is a constant related to the parameters of the inner tube, and f(x) represents the increase amplitude.

9. The potential control method according to claim 4, characterized in that: The method further comprises: Determine the initial voltage value of the input voltage of the flexible anode according to the statistical data of historical input voltage and operation time; or, The value of the input voltage before the most recent shutdown is used as the initial voltage value of the input voltage of the flexible anode.

10. The potential control method according to claim 9, characterized in that: The step of determining the initial voltage value of the input voltage of the flexible anode according to the statistical data of the historical input voltage and the operating time includes: The initial voltage value of the input voltage of the flexible anode is determined in the following manner: U = (U1t1+U2t2+...+Untn) / (t1+t2+...+tn); Among them, U represents the initial voltage value of the input voltage of the flexible anode, Ui represents the i-th historical input voltage, ti represents the operating time corresponding to the i-th historical input voltage, 1≤i≤n, and i and n are both positive integers greater than 1.

11. The potential control method according to claim 4, characterized in that: The step of obtaining the electrode potential of the inner tube after the input voltage of the flexible anode is turned off includes: When it is determined that the electrode potential is not in the protection potential interval, or after the target operation time is continuously operated according to the input voltage, the electrode potential of the inner tube is obtained after the input voltage of the flexible anode is turned off.

12. An electronic device, characterized in that: The electronic device comprises: a memory for storing one or more computer instructions; A processor, configured to call and execute the computer instructions to implement the method according to any one of claims 4 to 11.

13. A shell and tube heat exchanger, comprising: Inner tube; An outer tube sleeved on the outer side of the inner tube; And the anti-corrosion device as described in any one of claims 1-3.

14. A heat exchange unit, characterized in that: The heat exchange unit comprises a shell and tube heat exchanger and an anti-corrosion device as claimed in any one of claims 1 to 3; or, The heat exchange unit comprises a shell and tube heat exchanger, an anti-corrosion device according to any one of claims 1 to 3, and an electronic device according to claim 12.

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