A monitoring method, system and device for waste heat recovery system

Abstract

The present invention discloses a monitoring method, system and device for a waste heat recovery system, including: reading the surface temperature T of the heat exchange tube in the riser heat exchanger; judging whether the surface temperature T of the heat exchange tube satisfies T1‑A≤T≤T1; if the surface temperature T of the heat exchange tube satisfies T1‑A≤T≤T1, outputting a prompt that the circulating water volume of the riser heat exchanger is too large, and reducing the opening of the water inlet valve of the riser heat exchanger. The technical solution of the present invention can monitor the operating state of the riser heat exchanger in real time, and adjust the operating condition of the riser heat exchanger in real time according to the operating state of the riser heat exchanger. The solution provided by the present invention solves the problem that the operating condition of the riser heat exchanger cannot be monitored and adjusted in the prior art, and reduces or prevents the generation of graphite on the inner wall of the riser heat exchanger while ensuring the heat recovery efficiency, thereby reducing the equipment maintenance cost of the coking plant and improving the economic benefits of the coking plant.

Description

Technical Field

[0001] The present invention relates to the technical field of coking, and in particular to a monitoring method, system and device for a waste heat recovery system. Background Art

[0002] In the current coking field, coking coal is usually heated to about 1000℃ under the condition of being isolated from air, and coke is made through pyrolysis, carbonization, coking and other conversions. In order to recover a large amount of unused sensible heat in the coke oven, the waste heat in the raw coal gas is recovered through the waste heat recovery system for the coking plant's own use.

[0003] During the coke oven carbonization chamber turnover cycle, the temperature of the raw gas changes dramatically, resulting in a poor working environment for the waste heat recovery system, which in turn makes the waste heat recovery system prone to failure. In the relevant technology, there is no corresponding technical means to effectively monitor the status of the waste heat recovery system. Summary of the invention

[0004] The embodiments of the present application solve the technical problem that the operating conditions of the waste heat recovery system cannot be monitored in real time in the prior art by providing a monitoring method, system and device for the waste heat recovery system, thereby realizing real-time monitoring of the waste heat recovery system and adjusting the operating status of the waste heat recovery system according to the operating conditions of the waste heat recovery system.

[0005] In a first aspect, the present application provides a method for monitoring a waste heat recovery system, the method comprising:

[0006] Read the surface temperature T of the heat exchange tube in the riser heat exchanger;

[0007] Determine whether the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1;

[0008] If the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1, a prompt is output that the circulating water volume of the riser heat exchanger is too large, and the opening of the water inlet valve of the riser heat exchanger is reduced, where A is the water leakage alarm coefficient of the coke oven where the riser heat exchanger is located, and T1 is the saturation temperature of the steam drum in the riser heat exchanger at the corresponding operating pressure.

[0009] Furthermore, the method further comprises:

[0010] Determine whether the surface temperature T of the heat exchange tube satisfies T>T1+B;

[0011] If the surface temperature T of the heat exchange tube satisfies T>T1+B, a prompt is output that the circulating water volume of the riser heat exchanger is too small, and the opening of the water inlet valve of the riser heat exchanger is increased, where B is the overheat alarm coefficient of the coke oven where the riser heat exchanger is located.

[0012] Furthermore, the overheat alarm coefficient B of the riser heat exchanger is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger is located.

[0013] Furthermore, the method further comprises:

[0014] Determine whether the surface temperature T of the heat exchange tube satisfies T<T1-A;

[0015] If the surface temperature T of the heat exchange tube satisfies T<T1-A, a prompt of water leakage or burst of the heat exchange tube in the riser heat exchanger is output, and an audible and visual alarm signal is issued.

[0016] Furthermore, the water leakage alarm coefficient A of the riser heat exchanger is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger is located.

[0017] Furthermore, the method further comprises:

[0018] Determine whether the surface temperature T of the heat exchange tube satisfies T1<T≤T1+B;

[0019] If the surface temperature T of the heat exchange tube satisfies T1<T≤T1+B, a prompt indicating that the riser heat exchanger is operating normally is output.

[0020] Furthermore, the saturation temperature T1 of the steam drum of the riser heat exchanger is positively correlated with the operating pressure of the steam drum in the riser heat exchanger.

[0021] In a second aspect, the present application provides a monitoring system for a waste heat recovery system, the system comprising:

[0022] The temperature measuring device is used to measure the surface temperature T of the heat exchange tube in the riser heat exchanger;

[0023] The controller is connected to the temperature measuring device and is used to execute the method provided by the first aspect.

[0024] In a third aspect, the present application provides a monitoring device for a waste heat recovery system, the device comprising:

[0025] A reading module is used to read the surface temperature T of the heat exchange tube in the riser heat exchanger;

[0026] A judgment module, used to judge whether the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1;

[0027] The output module is used to output a prompt that the circulating water volume of the riser heat exchanger is too large when the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1, and to reduce the opening of the water inlet valve of the riser heat exchanger, wherein A is the water leakage alarm coefficient of the riser heat exchanger at the riser of the coke oven, and T1 is the saturation temperature of the steam drum in the riser heat exchanger at the riser of the coke oven at the corresponding operating pressure.

[0028] In a fourth aspect, the present application provides a controller comprising one or more processors and one or more memories, wherein at least one program code is stored in the one or more memories, and the at least one program code is loaded and executed by one or more processors to implement operations performed by a method provided in the first aspect.

[0029] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0030] The embodiment of the present application uses a monitoring system to read the surface temperature T of the heat exchange tube in the riser heat exchanger, and determines the temperature range of the surface temperature T. The waste heat recovery system is adjusted according to the range of the surface temperature T to improve the working condition of the riser heat exchanger. For example, if the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1, a prompt that the circulating water volume of the riser heat exchanger is too large is output, and the opening of the water inlet valve of the riser heat exchanger is reduced. The method provided by this embodiment solves the problem that the operating condition of the riser heat exchanger cannot be monitored and adjusted in the prior art. While ensuring the heat recovery efficiency, it also reduces or prevents the amount of graphite generated on the inner wall of the riser heat exchanger, reduces the equipment maintenance cost of the coking plant, and improves the economic benefits of the coking plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic diagram of the structure of a monitoring system for a waste heat recovery system provided in this application, specifically: Figure 2 An enlarged schematic diagram of the area marked by the middle circle;

[0033] Figure 2 for Figure 1 A schematic diagram of the positional relationship between the monitoring system and the riser heat exchanger provided in;

[0034] Figure 3 A schematic diagram of a flow chart of a monitoring method for a waste heat recovery system provided in this application;

[0035] Figure 4 An example flow chart of a monitoring method for a waste heat recovery system provided in this application;

[0036] Figure 5 It is a schematic diagram of the temperature variation of the raw coal gas at the inlet of the riser in each stage of the coke oven turnover cycle in the conventional technology;

[0037] Figure 6 This is a schematic diagram of the temperature change at the 21# riser heat exchanger in the example;

[0038] Figure 7 This is a schematic diagram of the temperature change at the 140# riser heat exchanger in the example;

[0039] Figure 8 A schematic diagram of the structure of a monitoring device for a waste heat recovery system provided in this application.

[0040] Reference numerals:

[0041] 1-riser tube heat exchanger, 2-thermocouple mounting base, 3-thermal insulation protective cover, 4-heat exchange tube, 5-thermocouple, 6-analog-to-digital conversion module, 7-riser tube. DETAILED DESCRIPTION

[0042] The embodiment of the present application solves the problem in the prior art that the operating status of the riser heat exchanger 1 cannot be monitored by providing a monitoring method for a waste heat recovery system.

[0043] The technical solution of the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows:

[0044] A monitoring method for a waste heat recovery system comprises: reading a surface temperature T of a heat exchange tube 4 in a riser heat exchanger 1; judging whether the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1; if the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1, outputting a prompt that the circulating water volume of the riser heat exchanger 1 is too large, and reducing the opening of a water inlet valve of the riser heat exchanger 1, wherein A is a water leakage alarm coefficient of a coke oven where the riser heat exchanger 1 is located, and T1 is a saturation temperature corresponding to the steam drum in the riser heat exchanger 1 at a corresponding operating pressure.

[0045] The embodiment of the present application uses a monitoring system to read the surface temperature T of the heat exchange tube 4 in the riser heat exchanger 1, and determines the temperature range of the surface temperature T. The waste heat recovery system is adjusted according to the range of the surface temperature T to improve the working condition of the riser heat exchanger 1. For example, if the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1, a prompt indicating that the circulating water volume of the riser heat exchanger 1 is too large is output, and the opening of the water inlet valve of the riser heat exchanger 1 is reduced. The method provided by this embodiment solves the problem that the operating condition of the riser heat exchanger 1 cannot be monitored and adjusted in the prior art. While ensuring the heat recovery efficiency, it also reduces or prevents the amount of graphite generated on the inner wall of the riser heat exchanger 1, reduces the equipment maintenance cost of the coking plant, and improves the economic benefits of the coking plant.

[0046] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0047] First of all, the term "and / or" in this article is only a description of the association relationship of the 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, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0048] This application provides Figure 1 The waste heat recovery system monitoring system shown includes:

[0049] A temperature measuring device, used to measure the surface temperature T of the heat exchange tube 4 in the riser heat exchanger 1;

[0050] The controller is connected to the temperature measuring device and can execute a waste heat recovery system monitoring method, which will be described later and will not be described in detail here.

[0051] During the coking process, coking coal is loaded into the coke oven carbonization chamber, where it is isolated from the air and distilled to generate a large amount of raw coal gas. After leaving the carbonization chamber, the raw coal gas passes through the riser, tee, and bridge pipe to the gas collecting pipe and is then transported to the gas purification process. Among them, the temperature of the raw coal gas when leaving the carbonization chamber is 650℃~950℃, and the high-temperature raw coal gas is cooled to about 80℃~85℃ by spraying circulating ammonia water at the bridge pipe. The temperature of the raw coal gas is reduced from 650℃~950℃ to 80℃~85℃, resulting in a large amount of sensible heat being wasted.

[0052] In order to reduce the waste rate of sensible heat, the riser is replaced with a riser heat exchanger 1 to recover the waste heat. The riser 7 and the heat exchanger can be combined in any form. For example, the heat exchanger can be arranged on the surface of the riser 7 in a winding manner to increase the contact area with the riser 7, thereby increasing the heat exchange area and improving the heat exchange efficiency. Figure 2 , which is a schematic diagram of the positional relationship between the monitoring system and the riser heat exchanger 1 provided in this embodiment. Specifically, the heat exchanger is wrapped around the surface of the riser 7 to achieve the purpose of covering the heat exchanger on the surface of the riser 7, thereby realizing waste heat recovery.

[0053] like Figure 1 As shown, the riser heat exchanger 1 is composed of a riser tube 7 and a heat exchanger, and the heat exchanger contains a heat exchange tube 4. A thermocouple mounting base 2 is provided on the middle shell of the riser heat exchanger 1, and the measuring end of the thermocouple 5 reaches the heat exchange tube 4 of the riser heat exchanger 1 through the heat insulation protective sleeve 3, and the surface temperature T of the heat exchange tube 4 is measured in real time. The measured temperature signal is converted into a digital signal by the analog-to-digital conversion module 6 and transmitted to the control system.

[0054] The heat exchange medium in the heat exchange tube 4 can be water or heat transfer oil. Using water as the heat exchange medium in the heat exchange tube 4 can prevent the leakage of the heat exchange tube 4 from causing environmental pollution; using heat transfer oil as the heat exchange medium in the heat exchange tube 4, compared with water as the heat exchange medium in the heat exchange tube 4, the heat transfer oil has better thermal stability, less coking, and longer service life, but when the heat exchange tube 4 leaks, it is easy to cause a fire accident and pollute the environment. The heat exchange medium can be selected according to the actual situation. This embodiment only takes water as an example for subsequent description.

[0055] The temperature measuring device can be set at any position on the surface of the riser heat exchanger 1, for example, it can be set at the upper, middle or lower part of the riser heat exchanger 1. The riser heat exchanger 1 is located at the top or upper part of the coke oven carbonization chamber, and the height of the coke oven carbonization chamber is relatively high. If the temperature measuring device is set at the upper part of the riser heat exchanger 1, additional lifting equipment is required to assist the maintenance personnel to rise to the position where the temperature measuring device is located when the temperature measuring device is inspected and maintained, which is not conducive to equipment inspection and maintenance. If the temperature measuring device is arranged at the lower part of the riser heat exchanger 1, the bottom of the riser is close to the raw gas inlet and the temperature is high, which makes the environment for maintenance personnel relatively bad. In addition, the temperature measuring device is in a high temperature environment for a long time, which may shorten the service life of the temperature measuring device. Moreover, when the heat exchange tube 4 in the riser heat exchanger 1 leaks, the temperature at the bottom of the riser 7 is high, resulting in no obvious temperature change when leaking. This embodiment mainly relies on the change amplitude of the temperature measured by the temperature measuring device to monitor the status of the riser heat exchanger 1. If the temperature change is not obvious, it is not conducive to the status monitoring of the riser heat exchanger 1.

[0056] Preferably, the temperature measuring device can be arranged in the middle of the riser heat exchanger 1 (i.e., the middle of the riser 7, see Figure 2 ), the height of the middle part of the riser 7 is similar to the height of a person, so the temperature measuring device can be inspected and repaired without relying on a lifting tool, and the temperature of the middle part of the riser 7 is moderate. If the riser heat exchanger 1 leaks, the leaked water can evaporate quickly and take away a large amount of heat, which will lead to a large temperature change. The abnormal state of the riser heat exchanger 1 can be detected more quickly through temperature monitoring, shortening the response time of maintenance, and reducing the negative impact of leakage on the furnace wall of the carbonization chamber to a certain extent.

[0057] The temperature measuring device can be any device capable of measuring the surface temperature of the heat exchange tube 4 in the riser heat exchanger 1, and can be a high temperature resistant thermometer, an infrared thermometer, a thermocouple, etc., and can be selected according to actual conditions.

[0058] In this embodiment, a thermocouple 5 is used to measure the surface temperature T of the heat exchange tube 4. Thermocouple temperature measurement has high accuracy, is not affected by ambient temperature, has a wide temperature measurement range, and has a fast dynamic response speed, and can be used to measure temperature in real time. The temperature signal generated by the thermocouple measurement can be transmitted remotely, which is more convenient for centralized detection and automatic control.

[0059] After the temperature measuring device measures the surface temperature T of the heat exchange tube 4, the surface temperature T is sent to the controller, or the controller reads the surface temperature T from the temperature measuring device, and then monitors the state of the waste heat recovery system according to the surface temperature T and its changes. The surface temperature T collected by the temperature measuring device is an analog signal. After the controller reads the surface temperature T from the temperature measuring device, the analog-to-digital conversion module 6 provided inside the controller performs signal conversion, converts the surface temperature T of the analog signal into the surface temperature T of the digital signal, and then monitors the state of the waste heat recovery system according to the surface temperature T of the digital signal and its changes.

[0060] Usually, a coke oven is equipped with multiple riser heat exchangers 1, and each riser heat exchanger 1 needs to be tested according to its temperature change. In actual operation, the corresponding heat exchange tube 4 or temperature measuring device in each riser heat exchanger 1 can be numbered, and the temperature signal detected by the temperature measuring device carries the number of the corresponding temperature measuring device, so that the controller can determine which riser heat exchanger 1 the received temperature signal belongs to. In other words, when the controller receives the surface temperature, it also needs to identify the corresponding temperature measuring device number.

[0061] The controller of the waste heat recovery system performs the following operations for each received surface temperature T: Figure 3 The monitoring method of the waste heat recovery system shown in the figure comprises (step S11-step S15):

[0062] Step S11, reading the surface temperature T of the heat exchange tube 4 in the riser heat exchanger 1;

[0063] Step S12, judging whether the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1; if the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1, outputting a prompt that the circulating water volume of the riser heat exchanger 1 is too large, and reducing the opening of the water inlet valve of the riser heat exchanger 1, wherein A is the water leakage alarm coefficient of the coke oven where the riser heat exchanger 1 is located, and T1 is the saturation temperature corresponding to the steam drum in the riser heat exchanger 1 at the corresponding operating pressure.

[0064] Step S13, judging whether the surface temperature T of the heat exchange tube 4 satisfies T>T1+B; if the surface temperature T of the heat exchange tube 4 satisfies T>T1+B, outputting a prompt that the circulating water volume of the riser heat exchanger 1 is too small, and increasing the opening of the water inlet valve of the riser heat exchanger 1, wherein B is the overheat alarm coefficient of the coke oven where the riser heat exchanger 1 is located.

[0065] Step S14, determine whether the surface temperature T of the heat exchange tube 4 satisfies T<T1-A; if the surface temperature T of the heat exchange tube 4 satisfies T<T1-A, output a prompt of water leakage or burst of the heat exchange tube 4 of the riser heat exchanger 1, and send out an audible and visual alarm signal.

[0066] Step S15, determining whether the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B; if the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B, outputting a prompt indicating that the riser heat exchanger 1 operates normally.

[0067] Regarding step S11, the surface temperature T can be detected by a detection device in the system, such as a thermocouple or other device, which will not be described in detail here. The specific measurement method can refer to the above description of the waste heat recovery system. The reading frequency of the surface temperature T can be set according to the actual situation. For example, for the temperature measuring device of each riser heat exchanger 1, the temperature can be read once every 1 second, or once every 10 seconds. Of course, it can also be set according to the service life of the temperature measuring device or the riser heat exchanger 1. When the temperature measuring device or the riser heat exchanger 1 is a new device, the probability of the new device having problems is small, so the temperature can be read every 5 seconds or longer; and when the temperature measuring device or the riser heat exchanger 1 is a device with a long service life, the probability of the device with a long service life having problems is greater than the probability of the new device having problems, so the temperature can be read once every 1 second or shorter.

[0068] Steps S12-S15 may be executed simultaneously or in a preset order. The preset order may be set according to actual conditions and is not limited here.

[0069] According to the temperature range of the surface temperature T (temperature range includes T1-A≤T≤T1, T>T1+B, T<T1-A and T1<T≤T1+B), the following processing methods can be used:

[0070] Range 1 [T1-A≤T≤T1]

[0071] Range 1 specifically corresponds to step S12. After the monitoring system reads the surface temperature T of the heat exchange tube 4, the monitoring system executes a judgment logic of whether the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1.

[0072] Wherein, T1 is the saturation temperature corresponding to the steam drum in the riser heat exchanger 1 at the corresponding operating pressure. The higher the pressure of the steam drum, the higher the corresponding saturation temperature. Specifically, the value of T1 can be determined by looking up the enthalpy-temperature table, as shown in Table 1, which is the relationship between the operating pressure and saturation temperature of a certain model of steam drum.

[0073] Table 1

[0074] Drum operating pressure (MPa) 0.4 0.6 1.0 1.6 2.0 2.5 T1 143 159 180 201 212 224

[0075] A is the water leakage alarm coefficient of the coke oven where the riser heat exchanger 1 is located. The coefficient A is related to the height of the coke oven carbonization chamber. The higher the height of the coke oven carbonization chamber, the greater the coefficient A. As shown in Table 2, it is the relationship between the height of different coke oven carbonization chambers and the coefficient A.

[0076] Table 2

[0077] Coke oven carbonization chamber height (m) A B 4.3～6 30～40 20～30 6～7 35～45 25～35 7～8 40～60 30～100

[0078] If the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1, it means that the amount of water in the heat exchange tube 4 is too large, a lot of water vapor is generated, and too much heat is taken away, resulting in a low temperature of the riser 7. Some high-boiling point tar fractions in the coke oven riser 7 are easily condensed by the cold inner wall. These condensates are pyrolyzed and condensed by heat transfer from the furnace top or convection heat transfer and solidify into graphite. In order to improve this situation, the monitoring system identifies the temperature measuring device number carried in the temperature signal, outputs a prompt that the circulating water volume of the riser heat exchanger 1 is too large for the riser heat exchanger 1 corresponding to the number, and adjusts the opening of the water inlet valve of the riser heat exchanger 1 to reduce the water flow in the riser heat exchange tube 4, reduce the heat taken away, increase the temperature of the riser 7, reduce the formation of graphite, and in a better case, avoid the formation of graphite on the inner wall of the riser 7.

[0079] Range 2 [T>T1+B]

[0080] Range 2 specifically corresponds to step S13. After the monitoring system reads the surface temperature T of the heat exchange tube 4, the monitoring system executes the judgment logic of whether the surface temperature T of the heat exchange tube 4 satisfies T>T1+B.

[0081] B is the overheat alarm coefficient of the coke oven where the riser heat exchanger 1 is located. The coefficient B is related to the height of the coke oven carbonization chamber. The higher the height of the coke oven carbonization chamber, the larger the coefficient B. As shown in Table 2, this is the relationship between the height of the coke oven carbonization chamber and B.

[0082] If the surface temperature T of the heat exchange tube 4 satisfies T>T1+B, it means that the amount of water in the heat exchange tube 4 is too small, the amount of steam generated is too small, and the heat taken away is small, resulting in too high temperature in the coke oven riser 7. At this time, the heat exchange efficiency is too low, and a lot of sensible heat will be wasted. In order to improve this situation, the monitoring system identifies the temperature measuring device number carried in the temperature signal, outputs a prompt that the circulating water volume of the riser heat exchanger 1 is too small for the riser heat exchanger 1 corresponding to the number, and outputs a control signal to increase the opening of the water inlet valve of the riser heat exchanger 1, increase the water flow in the heat exchange tube 4 in the riser heat exchanger 1, take away more heat in the riser 7, and improve the recovery rate of sensible heat.

[0083] Range 3 [T<T1-A]

[0084] Range 3 specifically corresponds to step S14. After the monitoring system reads the surface temperature T of the heat exchange tube 4, the monitoring system executes a judgment logic of whether the surface temperature T of the heat exchange tube 4 satisfies T<T1-A.

[0085] If the surface temperature T of the heat exchange tube 4 satisfies T<T1-A, it means that the riser heat exchanger 1 may have leaked or burst, and the leaked water quickly evaporates, taking away a large amount of heat, and the surface temperature of the heat exchange tube 4 drops rapidly. In order to quickly remind relevant personnel and reduce the amount of water leaking into the coke oven, the monitoring system identifies the temperature measuring device number carried in the temperature signal, outputs a reminder of water leakage or burst of the heat exchange tube 4 of the riser heat exchanger 1 for the riser heat exchanger 1 corresponding to the number, and sends out an audible and visual alarm signal to remind relevant personnel to cut off the water supply or take other measures as soon as possible.

[0086] Range 4 [T1<T≤T1+B]

[0087] Range 4 corresponds to step S15. After the monitoring system reads the surface temperature T of the heat exchange tube 4, the monitoring system executes the judgment logic of whether the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B.

[0088] If the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B, it means that the heat absorbed by the riser heat exchanger 1 is appropriate at this time, and graphite will not be formed on the inner wall of the riser 7, and its sensible heat recovery rate is also high. Then the monitoring system identifies the temperature measuring device number carried in the temperature signal, and can output a prompt that the riser heat exchanger 1 is operating normally for the riser heat exchanger 1 corresponding to the number, reminding relevant staff that the waste heat recovery system is operating normally.

[0089] The monitoring method provided above is repeatedly executed during the operation of the riser 7 to achieve the purpose of continuously monitoring the waste heat recovery system set up in the coke oven.

[0090] In summary, in this embodiment, the surface temperature T of the heat exchange tube 4 is detected by a temperature measuring device, and the actual operating state of the riser heat exchanger 1 is determined according to the surface temperature T. For example, when the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1, it means that the circulating water volume of the riser heat exchanger 1 is too large, and the opening of the water inlet valve of the riser heat exchanger 1 needs to be reduced; when the surface temperature T of the heat exchange tube 4 satisfies T>T1+B, it means that the circulating water volume of the riser heat exchanger 1 is too small, and the opening of the water inlet valve of the riser heat exchanger 1 needs to be increased; when the surface temperature T of the heat exchange tube 4 satisfies T<T1-A, it means that the heat exchange tube 4 in the riser heat exchanger 1 may leak or burst, and the waste heat recovery system sends out an audible and visual alarm signal to remind relevant personnel to deal with it in time; when the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B, it means that the circulating water volume of the riser heat exchanger 1 is moderate and the operating condition of the riser heat exchanger 1 is normal. This embodiment can ensure the heat recovery rate of the waste heat recovery system, and at the same time can reduce the amount of graphite formed on the inner wall of the riser 7, and even avoid the formation of graphite on the inner wall of the riser 7. In addition, it can also monitor in real time whether the riser heat exchanger 1 is in an abnormal working condition such as leakage or burst, so as to prevent damage to the furnace wall of the coke oven carbonization chamber caused by long-term leakage.

[0091] A waste heat recovery system is now taken as an example to illustrate steps S11 to S15.

[0092] An application example of using the waste heat of the 7.63m top-loading coke oven to produce 1.6MPa steam:

[0093] The 7.63-meter coke oven is a 2×70-hole top-mounted coke oven with an annual coke output of 2.06 million tons. 140 riser heat exchangers 1 equipped with the monitoring method and device of this embodiment are used to recover waste heat from raw coal gas and produce 1.5 MPa steam for the coking plant's own use. The monitoring system uses the method provided in this embodiment to realize automatic identification and judgment of the operating status of each riser heat exchanger 1, and takes corresponding control measures according to its operating status. At the same time, abnormal operating conditions such as leakage or burst of the riser heat exchanger 1 can be detected at any time to prevent damage to the furnace wall of the coke oven carbonization chamber caused by long-term leakage.

[0094] In this application example, referring to Table 1 above, when the drum operating pressure is 1.6MPa, the value of T1 is 201; referring to Table 2 above, when the height of the coke oven carbonization chamber is 7.63 meters, the value of the water leakage alarm coefficient A is 50 and the value of the overheating alarm coefficient B is 40.

[0095] The logic of waste heat recovery system operation can be found in Figure 4 .

[0096] Step 1, reading the surface temperature T of the heat exchange tube 4 in the riser heat exchanger 1 at a preset frequency, the surface temperature T being collected by a thermocouple;

[0097] Step 2, determine whether the surface temperature T of the heat exchange tube 4 satisfies 151≤T≤201; if the surface temperature T of the heat exchange tube 4 satisfies 151≤T≤201, output a prompt that the circulating water volume of the riser heat exchanger 1 is too large, and reduce the opening of the water inlet valve of the riser heat exchanger 1.

[0098] Step 3, determine whether the surface temperature T of the heat exchange tube 4 satisfies T>241; if the surface temperature T of the heat exchange tube 4 satisfies T>241, output a prompt that the circulating water volume of the riser heat exchanger 1 is too small, and increase the opening of the water inlet valve of the riser heat exchanger 1.

[0099] Step 4, determine whether the surface temperature T of the heat exchange tube 4 satisfies T<151; if the surface temperature T of the heat exchange tube 4 satisfies T<151, output a prompt of water leakage or burst of the heat exchange tube 4 of the riser heat exchanger 1, and send out an audible and visual alarm signal.

[0100] Step 5, judging whether the surface temperature T of the heat exchange tube 4 satisfies 201<T≤241; if the surface temperature T of the heat exchange tube 4 satisfies 201<T≤241, outputting a prompt indicating that the riser heat exchanger 1 operates normally.

[0101] The above steps 1-5 can be matched with the results in Table 3.

[0102] Table 3

[0103] Serial number Running status Detection logic Control Methods 1 Running normally 241≥T＞201 Maintain current working conditions without making any adjustments 2 Excessive circulating water volume 151≤T≤201 Reduce the opening of the water inlet valve 3 Circulating water volume is too small T＞241 Increase the opening of the water inlet valve 4 Leaking or burst pipe T＜151 Sound and light alarm and close the water inlet and outlet valves

[0104] After the project was debugged and operated normally, T1 generally varied between 203 and 231°C, the system steam production was 24.7t / h, the steam production rate per ton of coke was 105.1kg / t, and there was no obvious graphite accumulation or black smoke on the inner wall of the riser heat exchanger 1.

[0105] like Figure 5 The figure shows the temperature variation of the raw gas at the inlet of the riser in each stage of the coke oven turnover cycle in the conventional technology (i.e., the technology without the riser heat exchanger). During the coke oven carbonization chamber turnover cycle, the temperature of the raw gas changes dramatically during the coal loading and coke pushing stages, resulting in a poor working environment for the waste heat recovery system, which in turn makes the waste heat recovery system prone to failure.

[0106] like Figure 6 As shown, this is the temperature change curve of the 21# riser heat exchanger among the 140 riser heat exchangers 1. It can be seen that after replacing the riser 7 in the coke oven with the riser heat exchanger 1, not only the heat is recovered, but also the temperature fluctuation amplitude or frequency can be reduced, the harshness of the working environment of the riser 7 is improved, and the service life of the riser heat exchanger and the monitoring system is extended.

[0107] To simulate the leakage of heat exchange tube 4 in riser heat exchanger 1, 2 liters of water were injected into the upper steam release port of 140# riser heat exchanger at one time. The T change curve is as follows: Figure 7 As shown, the monitoring system starts to automatically sound and light alarm 40 seconds after water is injected. It can be seen that the monitoring method and monitoring system provided in this embodiment can effectively monitor the working status of the riser heat exchanger and reduce the damage to the coke oven caused by water leakage of the riser heat exchanger.

[0108] To sum up, the solution provided in this embodiment can ensure the heat recovery rate of the waste heat recovery system, while also reducing the amount of graphite formed on the inner wall of the riser 7, and even avoiding the formation of graphite on the inner wall of the riser 7. At the same time, it can monitor in real time whether the riser heat exchanger 1 is in abnormal conditions such as leakage or burst, to prevent long-term leakage from causing damage to the furnace wall of the coke oven carbonization chamber.

[0109] Based on the same inventive concept, the present application provides Figure 8 A monitoring device for a waste heat recovery system is shown, the device comprising:

[0110] A reading module 41 is used to read the surface temperature T of the heat exchange tube 4 in the riser heat exchanger 1;

[0111] A judgment module 42, used to judge whether the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1;

[0112] The output module 43 is used to output a prompt that the circulating water volume of the riser heat exchanger 1 is too large when the surface temperature T of the heat exchange tube 4 satisfies T1-A≤T≤T1, and to reduce the opening of the water inlet valve of the riser heat exchanger 1, wherein A is the water leakage alarm coefficient of the riser heat exchanger 1 at the coke oven riser, and T1 is the saturation temperature corresponding to the steam drum in the riser heat exchanger 1 at the coke oven riser at the corresponding operating pressure.

[0113] Furthermore, the judging module 42 is also used to judge whether the surface temperature T of the heat exchange tube 4 satisfies T>T1+B;

[0114] The output module 43 is also used to output a prompt that the circulating water volume of the riser heat exchanger 1 is too small when the surface temperature T of the heat exchange tube 4 satisfies T>T1+B, and to increase the opening of the water inlet valve of the riser heat exchanger 1, where B is the overheat alarm coefficient of the coke oven where the riser heat exchanger 1 is located.

[0115] Furthermore, the overheat alarm coefficient B of the riser heat exchanger 1 is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger 1 is located.

[0116] Furthermore, the judging module 42 is also used to judge whether the surface temperature T of the heat exchange tube 4 satisfies T<T1-A;

[0117] The output module 43 is also used to output a prompt of water leakage or burst of the heat exchange tube 4 in the riser heat exchanger 1 and send out an audible and visual alarm signal when the surface temperature T of the heat exchange tube 4 satisfies T<T1-A.

[0118] Furthermore, the water leakage alarm coefficient A of the riser heat exchanger 1 is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger 1 is located.

[0119] Furthermore, the judging module 42 is also used to judge whether the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B;

[0120] The output module 43 is also used to output a prompt indicating that the riser heat exchanger 1 is operating normally when the surface temperature T of the heat exchange tube 4 satisfies T1<T≤T1+B.

[0121] Based on the same inventive concept, the present application also provides a controller, including one or more processors and one or more memories, wherein at least one program code is stored in the one or more memories, and the at least one program code is loaded and executed by one or more processors to implement the operations performed by the aforementioned waste heat recovery system monitoring method.

[0122] Since the electronic device introduced in this embodiment is an electronic device used to implement the information processing method in the embodiment of the present application, based on the information processing method introduced in the embodiment of the present application, a person skilled in the art can understand the specific implementation of the electronic device of the present embodiment and its various variations, so how the electronic device implements the method in the embodiment of the present application is not described in detail here. As long as a person skilled in the art implements the electronic device used by the information processing method in the embodiment of the present application, it belongs to the scope of protection of this application.

[0123] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0124] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0125] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0126] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0127] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0128] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A monitoring method for a waste heat recovery system, characterized in that: The method comprises: Read the surface temperature T of the heat exchange tube in the riser heat exchanger; Determine whether the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1; If the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1, a prompt indicating that the circulating water volume of the riser heat exchanger is too large is output, and the opening of the water inlet valve of the riser heat exchanger is reduced, wherein A is the water leakage alarm coefficient of the coke oven where the riser heat exchanger is located, and T1 is the saturation temperature corresponding to the steam drum in the riser heat exchanger at the corresponding operating pressure; Determine whether the surface temperature T of the heat exchange tube satisfies T>T1+B; If the surface temperature T of the heat exchange tube satisfies T>T1+B, a prompt is outputted that the circulating water volume of the riser heat exchanger is too small, and the opening of the water inlet valve of the riser heat exchanger is increased, wherein B is the overheat alarm coefficient of the coke oven where the riser heat exchanger is located; the overheat alarm coefficient B of the riser heat exchanger is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger is located; Determine whether the surface temperature T of the heat exchange tube satisfies T<T1-A; If the surface temperature T of the heat exchange tube satisfies T<T1-A, a prompt of water leakage or tube burst in the riser heat exchanger is output, and an audible and visual alarm signal is issued; the water leakage alarm coefficient A of the riser heat exchanger is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger is located; Determine whether the surface temperature T of the heat exchange tube satisfies T1<T≤T1+B; If the surface temperature T of the heat exchange tube satisfies T1<T≤T1+B, a prompt indicating that the riser heat exchanger operates normally is output.

2. The method according to claim 1, characterized in that The saturation temperature T1 of the steam drum of the riser heat exchanger is positively correlated with the operating pressure of the steam drum in the riser heat exchanger.

3. A monitoring system for a waste heat recovery system, characterized in that: The system comprises: The temperature measuring device is used to measure the surface temperature T of the heat exchange tube in the riser heat exchanger; A controller, connected to the temperature measuring device, for executing the method according to any one of claims 1 to 2.

4. A monitoring device for a waste heat recovery system, characterized in that: The device comprises: A reading module is used to read the surface temperature T of the heat exchange tube in the riser heat exchanger; A judgment module is used to judge whether the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1; judge whether the surface temperature T of the heat exchange tube satisfies T>T1+B; judge whether the surface temperature T of the heat exchange tube satisfies T<T1-A; judge whether the surface temperature T of the heat exchange tube satisfies T1<T≤T1+B; The output module is used to output a prompt that the circulating water volume of the riser heat exchanger is too large when the surface temperature T of the heat exchange tube satisfies T1-A≤T≤T1, and reduce the opening of the water inlet valve of the riser heat exchanger, wherein A is the water leakage alarm coefficient of the riser heat exchanger at the coke oven riser, and T1 is the saturation temperature corresponding to the steam drum in the riser heat exchanger at the corresponding operating pressure; if the surface temperature T of the heat exchange tube satisfies T>T1+B, then output a prompt that the circulating water volume of the riser heat exchanger is too small, and increase the opening of the water inlet valve of the riser heat exchanger, wherein B is the The overheat alarm coefficient of the coke oven where the riser heat exchanger is located; the overheat alarm coefficient B of the riser heat exchanger is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger is located; if the surface temperature T of the heat exchange tube satisfies T<T1-A, a prompt of water leakage or burst of the heat exchange tube in the riser heat exchanger is output, and an audible and visual alarm signal is issued; the water leakage alarm coefficient A of the riser heat exchanger is positively correlated with the height of the coke oven carbonization chamber where the riser heat exchanger is located; if the surface temperature T of the heat exchange tube satisfies T1<T≤T1+B, a prompt of normal operation of the riser heat exchanger is output.

5. A controller, characterized in that: The method comprises one or more processors and one or more memories, wherein at least one program code is stored in the one or more memories, and the at least one program code is loaded and executed by one or more processors to implement the operations performed by the method according to any one of claims 1 to 2.

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