Air-cooled island full life cycle anti-corrosion system and method

Abstract

This invention provides a full life-cycle corrosion prevention system and method for air-cooled islands, relating to the field of corrosion prevention technology in the power industry, and aims to solve the problem of poor corrosion prevention effects of existing measures for air-cooled islands. It includes hydrogen peroxide supply pipelines and ethanolamine supply pipelines. The hydrogen peroxide supply pipeline is sequentially equipped with a hydrogen peroxide solution tank, a first dosing pump, and a hydrogen peroxide on / off valve. The ethanolamine supply pipeline is sequentially equipped with an ethanolamine solution tank, a second dosing pump, and an ethanolamine on / off valve. A corrosion rate monitoring module is installed in the main exhaust pipe, including a sensing electrode and a corrosion rate monitoring instrument electrically connected to the sensing electrode. The sensing electrode is installed inside the main exhaust pipe at its L-shaped bend. The outlet of the air-cooled island is connected to a fine treatment system via an output pipeline. The output pipeline is equipped with a condensate pump, and an online hydrogen conductivity meter and a first online hydrogen peroxide meter are installed at the outlet of the condensate pump. This invention provides good corrosion prevention effects.

Description

Technical Field

[0001] This invention relates to the field of corrosion prevention technology in the power industry, and more specifically, to a full life-cycle corrosion prevention system and method for air-cooled islands. Background Technology

[0002] Air-cooled islands are devices that use air as a cooling medium to cool high-temperature steam. They are mainly composed of fans and can save water resources and reduce environmental pollution. Reheated steam passes through a low-pressure cylinder to form exhaust steam, which then enters the main exhaust pipe. At this point, a two-phase flow (vapor-liquid ratio) forms in the main exhaust pipe, with a vapor-liquid ratio of 5–10:1. Because the vapor-liquid ratio in the main exhaust pipe is higher than that in the air-cooled island, liquid-phase corrosion is most severe in the main exhaust pipe. When the boiler uses ammonia to adjust the pH, due to the large vapor-liquid distribution coefficient of ammonia, when a two-phase flow exists in the main exhaust pipe and the air-cooled island, ammonia is mainly distributed in the vapor phase, with very little ammonia in the liquid phase. This results in a lower liquid-phase pH, thus exacerbating corrosion at the vapor-liquid flow points in the main exhaust pipe and the air-cooled island.

[0003] Currently, the corrosion prevention measures adopted at the main exhaust pipe and the air-cooled island's vapor-liquid two-phase flow section involve increasing the ammonia dosage to raise the feedwater pH to around 9.4. This approach results in a short operating cycle for the fine treatment process, which not only increases the workload of fine treatment regeneration but also generates a large amount of wastewater. Furthermore, due to the vapor-liquid distribution coefficient of ammonia, the pH increase of the liquid phase at the vapor-liquid two-phase flow section of the main exhaust pipe and the air-cooled island is very low, resulting in negligible effects. Summary of the Invention

[0004] The first objective of this invention is to provide a full life-cycle corrosion protection system for air-cooled islands, in order to solve the technical problem that the existing measures for corrosion protection of air-cooled islands are ineffective.

[0005] The air-cooled island full life-cycle corrosion prevention system provided by this invention includes a hydrogen peroxide supply pipeline and an ethanolamine supply pipeline, both connected to the main exhaust pipe. The hydrogen peroxide supply pipeline is sequentially equipped with a hydrogen peroxide solution tank, a first dosing pump, and a hydrogen peroxide on / off valve. The ethanolamine supply pipeline is sequentially equipped with an ethanolamine solution tank, a second dosing pump, and an ethanolamine on / off valve. The main exhaust pipe is equipped with a corrosion rate monitoring module, which includes a sensing electrode and a corrosion rate monitoring instrument electrically connected to the sensing electrode. The main exhaust pipe is L-shaped, and the sensing electrode is installed inside the main exhaust pipe at its L-shaped bend. The outlet of the main exhaust pipe is connected to the inlet of the air-cooled island. The outlet of the air-cooled island is connected to a fine treatment system via an output pipeline. The output pipeline is equipped with a condensate pump, and an online hydrogen conductivity meter and a first online hydrogen peroxide meter are installed at the outlet of the condensate pump.

[0006] Furthermore, the hydrogen peroxide supply pipeline is also provided with a hydrogen peroxide storage tank and a first metering pump in sequence upstream of the hydrogen peroxide solution tank. The hydrogen peroxide solution tank is provided with a first water inlet. The first water inlet is connected to the demineralized water tank through a first water supply pipeline. The first water inlet pipeline is provided with a first valve. The hydrogen peroxide solution tank is provided with a second online hydrogen peroxide meter for monitoring the internal hydrogen peroxide concentration.

[0007] The ethanolamine supply pipeline is also provided with an ethanolamine storage tank and a second metering pump upstream of the ethanolamine solution tank. The ethanolamine solution tank has a second water inlet, which is connected to the demineralized water tank through a second water supply pipeline. The second water inlet pipeline is equipped with a second valve. The ethanolamine solution tank is equipped with an online conductivity meter for monitoring the internal ethanolamine concentration.

[0008] Furthermore, the air-cooled island's full life-cycle corrosion protection system also includes a dilution water pump, the inlet of which is connected to the demineralized water tank, and both the first water supply pipeline and the second water supply pipeline are connected to the outlet of the dilution water pump.

[0009] Furthermore, the first water inlet is located at the top of the hydrogen peroxide solution tank, and the second water inlet is located at the top of the ethanolamine solution tank.

[0010] Furthermore, the corrosion rate monitoring module also includes a hollow cylindrical shell, one end of which is a closed end and the other end of which is an open end. The shell is fixedly disposed on the main exhaust pipe, with the closed end located inside the main exhaust pipe and the open end located outside the main exhaust pipe. The sensing electrode is fixedly disposed on the closed end and is connected to the corrosion rate monitor via a wire, which is housed within the inner cavity of the shell.

[0011] Furthermore, the sensing electrode includes a working electrode and an auxiliary electrode, both of which are fixedly disposed at the closed end. The working electrode is directly opposite to the steam flow direction inside the main exhaust pipe, and the auxiliary electrode is disposed on the outer periphery of the working electrode and is parallel to the steam flow direction inside the main exhaust pipe. The distance between the working electrode and the auxiliary electrode is 2 mm.

[0012] Furthermore, the main exhaust pipe has a threaded hole in its wall, and the housing has an external thread that is helically engaged with the threaded hole.

[0013] The beneficial effects of the air-cooled island full life-cycle corrosion prevention system of this invention are:

[0014] During the operation of this air-cooled island's full life-cycle corrosion prevention system, the hydrogen peroxide on / off valve can be kept in the off state during unit startup and shutdown to disconnect the hydrogen peroxide supply pipeline from the main exhaust pipe, while the ethanolamine on / off valve is kept in the open state to connect the ethanolamine supply pipeline to the main exhaust pipe. At this time, under the action of the second dosing pump, the ethanolamine solution from the ethanolamine solution tank will enter the main exhaust pipe through the ethanolamine supply pipeline. During this process, the internal condition of the main exhaust pipe is monitored using the sensing electrodes of the corrosion rate monitoring module, and the monitored parameters are output to the corrosion rate monitoring instrument to obtain the current corrosion rate of the main exhaust pipe. When the corrosion rate is greater than the first rate, the dosing frequency of the second dosing pump can be increased; when the corrosion rate is greater than the second rate but less than or equal to the first rate, the dosing frequency of the second dosing pump can be kept unchanged; when the corrosion rate is less than or equal to the second rate, the dosing frequency of the second dosing pump can be decreased.

[0015] When the unit is operating normally and the value monitored by the online hydrogen conductivity meter is less than the set hydrogen conductivity, it indicates that the water quality is normal. The hydrogen peroxide on / off valve can be opened to connect the hydrogen peroxide supply pipeline to the main exhaust pipe, while the ethanolamine on / off valve is closed to disconnect the ethanolamine supply pipeline from the main exhaust pipe. At this time, under the action of the first dosing pump, the hydrogen peroxide solution from the tank will enter the main exhaust pipe through the hydrogen peroxide supply pipeline. During this process, when the first online hydrogen peroxide meter detects a hydrogen peroxide concentration less than the first concentration, the dosing frequency of the first dosing pump can be increased; when the first online hydrogen peroxide meter detects a hydrogen peroxide concentration greater than or equal to the first concentration and less than the second concentration, the dosing frequency of the first dosing pump can be kept unchanged; when the first online hydrogen peroxide meter detects a hydrogen peroxide concentration greater than or equal to the second concentration, the dosing frequency of the first dosing pump can be decreased.

[0016] When the unit is operating normally and the value monitored by the online hydrogen conductivity meter is greater than or equal to the set hydrogen conductivity, it indicates that the water quality is abnormal. Ethanolamine is then added to the main exhaust pipe. The logic for adding ethanolamine is the same as that for adding ethanolamine during unit startup and shutdown.

[0017] In this full-lifecycle corrosion prevention system for air-cooled islands, the sensing electrode of the corrosion rate monitoring module is installed at the L-shaped bend of the main exhaust pipe. This in-situ installation of the sensing electrode allows for timely and accurate monitoring of the location of the most severe corrosion on the main exhaust pipe, effectively preventing corrosion of the air-cooled island. Furthermore, this invention utilizes ethanolamine as an alkalizing agent to increase the pH value and hydrogen peroxide as an oxidizing agent, achieving different corrosion prevention treatments throughout the entire service life of the air-cooled island, effectively inhibiting corrosion.

[0018] The second objective of this invention is to provide a method for corrosion prevention throughout the entire life cycle of an air-cooled island, in order to solve the technical problem that the existing measures for corrosion prevention of air-cooled islands are ineffective.

[0019] The air-cooled island full life cycle corrosion prevention method provided by this invention uses the above-mentioned air-cooled island full life cycle corrosion prevention system for corrosion prevention treatment, and includes the following steps:

[0020] When starting and stopping the unit, disconnect the hydrogen peroxide on / off valve and open the ethanolamine on / off valve, and use the second dosing pump to add ethanolamine from the ethanolamine solution tank to the main exhaust pipe.

[0021] When the unit is operating normally and the value monitored by the online hydrogen conductivity meter is less than the set hydrogen conductivity, open the hydrogen peroxide on / off valve, close the ethanolamine on / off valve, and use the first dosing pump to add hydrogen peroxide from the hydrogen peroxide solution tank to the main exhaust pipe.

[0022] When the unit is operating normally and the value monitored by the online hydrogen conductivity meter is greater than or equal to the set hydrogen conductivity, disconnect the hydrogen peroxide on / off valve, open the ethanolamine on / off valve, and use the second dosing pump to add ethanolamine from the ethanolamine solution tank to the main exhaust pipe.

[0023] Furthermore, the step of adding ethanolamine from the ethanolamine solution tank to the main exhaust pipe using the second dosing pump also includes monitoring the current corrosion rate of the main exhaust pipe using a corrosion rate monitoring module.

[0024] When the corrosion rate is greater than the first rate, increase the dosing frequency of the second dosing pump;

[0025] When the corrosion rate is greater than the second rate and less than or equal to the first rate, the dosing frequency of the second dosing pump remains unchanged;

[0026] When the corrosion rate is less than or equal to the second rate, reduce the dosing frequency of the second dosing pump;

[0027] The first speed is greater than the second speed.

[0028] Furthermore, the step of adding hydrogen peroxide from the hydrogen peroxide solution tank to the main exhaust pipe using the first dosing pump also includes monitoring the hydrogen peroxide concentration using a first online hydrogen peroxide meter:

[0029] When the hydrogen peroxide concentration is lower than the first concentration, increase the dosing frequency of the first dosing pump;

[0030] When the hydrogen peroxide concentration is greater than or equal to the first concentration and less than the second concentration, the dosing frequency of the first dosing pump remains unchanged;

[0031] When the hydrogen peroxide concentration is greater than or equal to the second concentration, reduce the dosing frequency of the first dosing pump;

[0032] The first concentration is less than the second concentration.

[0033] The beneficial effects of the air-cooled island's full life-cycle corrosion prevention method of this invention are:

[0034] The air-cooled island full life cycle corrosion prevention method adopts the above-mentioned air-cooled island full life cycle corrosion prevention system for corrosion prevention treatment. Accordingly, the air-cooled island full life cycle corrosion prevention method has all the advantages of the above-mentioned air-cooled island full life cycle corrosion prevention system, which will not be elaborated here. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of the air-cooled island full life-cycle corrosion protection system provided in an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of the corrosion rate monitoring module of the air-cooled island full life cycle corrosion prevention system provided in this embodiment of the invention, installed on the main exhaust pipe;

[0038] Figure 3 This is a partial structural diagram of the corrosion rate monitoring module of the air-cooled island full life cycle corrosion prevention system provided in an embodiment of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 100-Main exhaust pipe; 200-Hydrogen peroxide supply pipeline; 300-Ethanolamine supply pipeline; 400-Corrosion rate monitoring module; 500-Air cooling island; 600-Output pipeline; 700-Fine treatment system; 800-Demineralized water tank; 900-Dilution water pump;

[0041] 210 - Hydrogen peroxide storage tank; 220 - First metering pump; 230 - Hydrogen peroxide solution tank; 231 - First inlet; 240 - First dosing pump; 250 - Hydrogen peroxide on / off valve; 260 - First water supply pipeline; 270 - First valve; 280 - Second online hydrogen peroxide meter;

[0042] 310 - Ethanolamine storage tank; 320 - Second metering pump; 330 - Ethanolamine solution tank; 331 - Second water inlet; 340 - Second dosing pump; 350 - Ethanolamine on / off valve; 360 - Second water supply pipeline; 370 - Second valve; 380 - Online conductivity meter;

[0043] 410 - Induction electrode; 411 - Working electrode; 412 - Auxiliary electrode; 420 - Corrosion rate monitor; 430 - Housing; 431 - External thread; 440 - Wire;

[0044] 610 - Condensate pump; 620 - Online hydrogen conductivity meter; 630 - First online hydrogen peroxide meter. Detailed Implementation

[0045] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0046] Figure 1 This is a structural diagram of the full life-cycle corrosion protection system for the air-cooled island provided in this embodiment. Figure 1 As shown, this embodiment provides a full life-cycle corrosion prevention system for an air-cooled island, including a hydrogen peroxide supply pipeline 200 and an ethanolamine supply pipeline 300, both connected to the main exhaust pipe 100. The hydrogen peroxide supply pipeline 200 is sequentially equipped with a hydrogen peroxide solution tank 230, a first dosing pump 240, and a hydrogen peroxide on / off valve 250. The ethanolamine supply pipeline 300 is sequentially equipped with an ethanolamine solution tank 330, a second dosing pump 340, and an ethanolamine on / off valve 350. The main exhaust pipe 100 is equipped with a corrosion rate monitoring module 400, which includes a sensing electrode 410 and a corrosion rate monitoring instrument 420 electrically connected to the sensing electrode 410.

[0047] Figure 2 This is a schematic diagram showing the installation of the corrosion rate monitoring module 400 of the air-cooled island's full life-cycle corrosion protection system provided in this embodiment on the main exhaust pipe 100. Please continue to refer to... Figure 1 and combined Figure 2 The main exhaust pipe 100 is L-shaped, and the induction electrode 410 is installed inside the main exhaust pipe 100 and located at its L-shaped bend. The outlet of the main exhaust pipe 100 is connected to the inlet of the air-cooled island 500. The outlet of the air-cooled island 500 is connected to the fine treatment system 700 through the output pipe 600. The output pipe 600 is equipped with a condensate pump 610. An online hydrogen conductivity meter 620 and a first online hydrogen peroxide meter 630 are installed at the outlet of the condensate pump 610 in the output pipe 600.

[0048] During the operation of the air-cooled island's full life-cycle corrosion prevention system, when the unit starts up and stops, the hydrogen peroxide on / off valve 250 can be in the off state to cut off the connection between the hydrogen peroxide supply pipeline 200 and the main exhaust pipe 100, and the ethanolamine on / off valve 350 can be in the open state to connect the ethanolamine supply pipeline 300 and the main exhaust pipe 100. At this time, under the action of the second dosing pump 340, the ethanolamine solution in the ethanolamine solution tank 330 will enter the main exhaust pipe 100 through the ethanolamine supply pipeline 300. During this process, the induction electrode 410 of the corrosion rate monitoring module 400 is used to monitor the internal condition of the main exhaust pipe 100, and the monitored relevant parameters are output to the corrosion rate monitoring instrument 420 to obtain the current corrosion rate of the main exhaust pipe 100. When the corrosion rate is greater than the first rate, the dosing frequency of the second dosing pump 340 can be increased; when the corrosion rate is greater than the second rate but less than or equal to the first rate, the dosing frequency of the second dosing pump 340 can be kept unchanged; when the corrosion rate is less than or equal to the second rate, the dosing frequency of the second dosing pump 340 can be decreased.

[0049] When the unit is operating normally and the value monitored by the online hydrogen conductivity meter 620 is less than the set hydrogen conductivity, it indicates that the water quality is normal. The hydrogen peroxide on / off valve 250 can be opened to connect the hydrogen peroxide supply pipeline 200 to the main exhaust pipe 100, while the ethanolamine on / off valve 350 is closed to disconnect the ethanolamine supply pipeline 300 from the main exhaust pipe 100. At this time, under the action of the first dosing pump 240, the hydrogen peroxide solution in the hydrogen peroxide solution tank 230 will be supplied through the hydrogen peroxide supply... Pipeline 200 enters the main exhaust pipe 100. During this process, when the first online hydrogen peroxide meter 630 detects that the hydrogen peroxide concentration is less than the first concentration, the dosing frequency of the first dosing pump 240 can be increased; when the first online hydrogen peroxide meter 630 detects that the hydrogen peroxide concentration is greater than or equal to the first concentration and less than the second concentration, the dosing frequency of the first dosing pump 240 can be kept unchanged; when the first online hydrogen peroxide meter 630 detects that the hydrogen peroxide concentration is greater than or equal to the second concentration, the dosing frequency of the first dosing pump 240 can be decreased.

[0050] When the unit is operating normally and the value monitored by the online hydrogen conductivity meter 620 is greater than or equal to the set hydrogen conductivity, it indicates that the water quality is abnormal. Ethanolamine is added to the main exhaust pipe 100. The logic for adding ethanolamine is the same as the logic for adding ethanolamine during unit startup and shutdown.

[0051] In this full-lifecycle corrosion prevention system for the air-cooled island, by installing the sensing electrode 410 of the corrosion rate monitoring module 400 at the L-shaped bend of the main exhaust pipe 100, i.e., by installing the sensing electrode 410 in situ, the location of the main exhaust pipe 100 with the greatest corrosion can be monitored in a timely and accurate manner, effectively preventing corrosion of the air-cooled island 500. Furthermore, this invention utilizes ethanolamine as an alkalizing agent to increase the pH value and hydrogen peroxide as an oxidizing agent, achieving different corrosion prevention treatments throughout the entire service life of the air-cooled island 500, which can effectively inhibit corrosion of the air-cooled island 500.

[0052] Please continue to refer to Figure 1 In this embodiment, a hydrogen peroxide storage tank 210 and a first metering pump 220 are sequentially arranged upstream of the hydrogen peroxide solution tank 230 in the hydrogen peroxide supply pipeline 200. The hydrogen peroxide solution tank 230 has a first inlet 231, which is connected to the demineralized water tank 800 through a first water supply pipeline 260. The first water supply pipeline is equipped with a first valve 270. The hydrogen peroxide solution tank 230 is equipped with a second online hydrogen peroxide meter 280 for monitoring the internal hydrogen peroxide concentration.

[0053] By setting a second online hydrogen peroxide meter 280, the concentration of hydrogen peroxide inside the hydrogen peroxide solution tank 230 can be monitored. When the solution level in the hydrogen peroxide solution tank 230 is lower than the alarm level (the alarm level is higher than the minimum level), the first metering pump 220 starts and stops after a first set time to replenish hydrogen peroxide into the hydrogen peroxide solution tank 230, and the first valve 270 opens to replenish demineralized water into the hydrogen peroxide solution tank 230. When the second online hydrogen peroxide meter 280 detects that the hydrogen peroxide solution has reached the set concentration, the first valve 270 closes to prevent demineralized water from entering the hydrogen peroxide solution tank 230, thereby achieving the desired concentration of hydrogen peroxide solution in the hydrogen peroxide solution tank 230.

[0054] Please continue to refer to Figure 1 In this embodiment, an ethanolamine storage tank 310 and a second metering pump 320 are sequentially arranged upstream of the ethanolamine solution tank 330 in the ethanolamine supply pipeline 300. The ethanolamine solution tank 330 is provided with a second water inlet 331, which is connected to the demineralized water tank 800 through a second water supply pipeline 360. The second water inlet pipeline is provided with a second valve 370. The ethanolamine solution tank 330 is provided with an online conductivity meter 380 for monitoring the internal ethanolamine concentration.

[0055] By setting an online conductivity meter 380, the concentration of ethanolamine inside the ethanolamine solution tank 330 can be monitored. When the solution level in the ethanolamine solution tank 330 is lower than the alarm level (the alarm level is higher than the minimum level), the second metering pump 320 starts and stops after a second set time to replenish ethanolamine into the ethanolamine solution tank 330. At the same time, the second valve 370 opens to replenish demineralized water into the ethanolamine solution tank 330. When the online conductivity meter 380 detects that the ethanolamine solution has reached the set concentration, the second valve 370 closes to prevent demineralized water from entering the ethanolamine solution tank 330, thereby achieving the desired concentration of ethanolamine solution in the ethanolamine solution tank 330.

[0056] The air-cooled island's full life-cycle corrosion protection system, through the aforementioned design, can promptly replenish the hydrogen peroxide solution in tank 230 with the required concentration when the hydrogen peroxide solution is insufficient, and promptly replenish the ethanolamine solution in tank 330 with the required concentration when the ethanolamine solution is insufficient, thus ensuring the smooth implementation of subsequent corrosion protection processes. Moreover, this online solution replenishment process does not require unit shutdown and will not affect the unit's production capacity.

[0057] It should be noted that in this embodiment, corresponding level gauges can be installed in both the hydrogen peroxide solution tank 230 and the ethanolamine solution tank 330 to issue an alarm in time when the liquid level is insufficient.

[0058] It should also be noted that, in this embodiment, how to use the first online hydrogen peroxide meter 630 to monitor the solution concentration of the output pipeline 600, how to use the second online hydrogen peroxide meter 280 to monitor the solution concentration of the hydrogen peroxide solution tank 230, and how to use the online conductivity meter 380 to monitor the ethanolamine concentration of the ethanolamine solution tank 330 are all things that those skilled in the art can obtain based on the prior art, and are not the focus of this application's improvement, so they will not be described in detail here.

[0059] In this embodiment, the hydrogen peroxide on / off valve 250, the ethanolamine on / off valve 350, the first valve 270, and the second valve 370 can all be electrically controlled valves. Through the above-described configuration, this application enables the entire lifecycle corrosion protection system of the air-cooled island to be fully automated from the preparation process to the dosing process. This automates the operation, requires no human intervention, and has a high degree of automation.

[0060] Please continue to refer to Figure 1 In this embodiment, the air-cooled island's full life-cycle corrosion protection system may further include a dilution water pump 900, wherein the inlet of the dilution water pump 900 is connected to the demineralized water tank 800, and the first water supply pipeline 260 and the second water supply pipeline 360 ​​are both connected to the outlet of the dilution water pump 900.

[0061] The dilution pump 900 provides pumping power from the demineralized water tank 800 to the first water supply line 260 and from the demineralized water tank 800 to the second water supply line 360, so that the demineralized water in the demineralized water tank 800 can flow smoothly to the first water supply line 260 and the second water supply line 360.

[0062] Please continue to refer to Figure 1 In this embodiment, the first water inlet 231 is located at the top of the hydrogen peroxide solution tank 230.

[0063] This design allows the demineralized water to swirl into the hydrogen peroxide solution tank 230 as it is replenished through the first inlet 231, thus agitating the hydrogen peroxide already added to the tank and ensuring thorough mixing of the demineralized water and hydrogen peroxide.

[0064] Please continue to refer to Figure 1 In this embodiment, similarly, the second inlet 331 is located at the top of the ethanolamine solution tank 330.

[0065] This design allows the demineralized water to swirl into the ethanolamine solution tank 330 as it is replenished through the second inlet 331, thus agitating the ethanolamine already added to the tank and ensuring thorough mixing of the demineralized water and the ethanolamine.

[0066] Figure 3 This is a partial structural diagram of the corrosion rate monitoring module 400 of the air-cooled island full life-cycle corrosion protection system provided in this embodiment. Please continue to refer to... Figure 2 and combined Figure 3 In this embodiment, the corrosion rate monitoring module 400 may further include a hollow cylindrical shell 430, one end of which is a closed end and the other end of which is an open end. The shell 430 is fixedly disposed on the main exhaust pipe 100, with the closed end located inside the main exhaust pipe 100 and the open end located outside the main exhaust pipe 100. The sensing electrode 410 is fixedly disposed on the closed end and is connected to the corrosion rate monitor 420 via a wire 440, which is housed within the inner cavity of the shell 430.

[0067] Through the above-mentioned configuration, the corrosion rate monitoring module 400 not only enables the sensing electrode 410 to be located in the main exhaust pipe 100 to obtain the corresponding internal parameters of the main exhaust pipe 100, but also protects the connection between the wire 440 and the sensing electrode 410 by setting the wire 440 in the inner cavity of the housing 430, reducing the risk of the wire 440 becoming loose. At the same time, it can also prevent the steam inside the main exhaust pipe 100 from corroding the wire 440 and causing a short circuit.

[0068] Please continue to refer to Figure 2 and Figure 3 In this embodiment, the sensing electrode 410 may include a working electrode 411 and an auxiliary electrode 412. Both the working electrode 411 and the auxiliary electrode 412 are fixedly disposed at the closed end. The working electrode 411 is aligned with the steam flow direction inside the main exhaust pipe 100 (from...). Figure 2 (Indicated by the downward arrow) The auxiliary electrode 412 is located on the outer periphery of the working electrode 411 and is parallel to the steam flow direction inside the main exhaust pipe 100. The distance between the working electrode 411 and the auxiliary electrode 412 is 2mm.

[0069] When the air-cooled island's full life-cycle corrosion protection system is in operation, the corrosion rate monitor 420 uses the linear potential scanning method to test the total resistance between the working electrode 411 and the auxiliary electrode 412. After completing the test of the total resistance, the corrosion rate monitor 420 can be used to continuously test the solution resistance inside the main exhaust pipe 100 three times and take the average value. The polarization resistance is obtained based on the total resistance and the average resistance, so that the corrosion rate monitor 420 can calculate the corrosion rate based on the polarization resistance.

[0070] In this embodiment, by aligning the working electrode 411 of the sensing electrode 410 with the steam flow direction inside the main exhaust pipe 100, the steam can directly impact the working electrode 411 during its flow through the main exhaust pipe 100, thus improving the accuracy of the solution resistance test. Furthermore, by setting the distance between the working electrode 411 and the auxiliary electrode 412 to 2 mm, the accuracy of testing the resistance of solutions with low conductivity is also improved.

[0071] It should be noted that the working electrode 411 and the auxiliary electrode 412 of the sensing electrode 410 will undergo an electrochemical reaction during operation. The total resistance between the working electrode 411 and the auxiliary electrode 412 and the solution resistance inside the main exhaust pipe 100 are measured through this electrochemical reaction. The specific testing principle can be obtained by those skilled in the art based on the prior art, and it is not the focus of this application, so it will not be described in detail.

[0072] Please continue to refer to Figure 3 In this embodiment, the main exhaust pipe 100 has a threaded hole in its pipe wall, and the housing 430 has an external thread 431, wherein the external thread 431 is helically engaged with the threaded hole.

[0073] The installation method of the housing 430 on the main exhaust pipe 100 not only ensures installation stability, but also allows for disassembly and maintenance after a period of use, making maintenance highly convenient.

[0074] It should be noted that sealant can be applied at the connection between the housing 430 and the main exhaust pipe 100 to prevent steam leakage inside the main exhaust pipe 100.

[0075] Furthermore, this embodiment also provides a full life-cycle corrosion prevention method for air-cooled islands, employing the aforementioned full life-cycle corrosion prevention system for air-cooled islands, including the following steps: during unit startup and shutdown, disconnect the hydrogen peroxide on / off valve 250, open the ethanolamine on / off valve 350, and use the second dosing pump 340 to add ethanolamine from the ethanolamine solution tank 330 to the main exhaust pipe 100; during normal unit operation and when the value monitored by the online hydrogen conductivity meter 620 is less than the set hydrogen conductivity... When the unit is running normally and the value monitored by the online hydrogen conductivity meter 620 is greater than or equal to the set hydrogen conductivity, the hydrogen peroxide on / off valve 250 is opened, the ethanolamine on / off valve 350 is opened, and the ethanolamine solution tank 330 is added to the main exhaust pipe 100 using the first dosing pump 240.

[0076] The air-cooled island full life cycle corrosion prevention method adopts the above-mentioned air-cooled island full life cycle corrosion prevention system for corrosion prevention treatment. Accordingly, the air-cooled island full life cycle corrosion prevention method has all the advantages of the above-mentioned air-cooled island full life cycle corrosion prevention system, which will not be elaborated here.

[0077] In this embodiment, the hydrogen conductivity is set to 0.2 μS / cm.

[0078] Specifically, the above-mentioned step of adding ethanolamine from the ethanolamine solution tank 330 to the main exhaust pipe 100 using the second dosing pump 340 also includes using the corrosion rate monitoring module 400 to monitor the current corrosion rate of the main exhaust pipe 100: when the corrosion rate is greater than the first rate, the dosing frequency of the second dosing pump 340 is increased; when the corrosion rate is greater than the second rate but less than or equal to the first rate, the dosing frequency of the second dosing pump 340 is kept unchanged; when the corrosion rate is less than or equal to the second rate, the dosing frequency of the second dosing pump 340 is decreased; wherein, the first rate is greater than the second rate.

[0079] In this embodiment, the first speed can be 0.1 mm / a, and the second speed can be 0.05 mm / a.

[0080] Through the above settings, the dosing frequency of the second dosing pump 340 can be adjusted in real time according to the corrosion rate during the operation of the air-cooled island's full life-cycle corrosion protection system. Specifically, when the corrosion rate is high, the dosing frequency of the second dosing pump 340 is increased to rapidly raise the pH value; when the corrosion rate is low, the dosing frequency of the second dosing pump 340 remains constant or decreases to allow the pH value to rise slowly. This setting achieves dynamic adjustment of the dosing frequency of the second dosing pump 340, effectively meeting the corresponding corrosion protection requirements.

[0081] Specifically, the above-mentioned step of adding hydrogen peroxide from the hydrogen peroxide solution tank 230 to the main exhaust pipe 100 using the first dosing pump 240 also includes monitoring the hydrogen peroxide concentration using the first online hydrogen peroxide meter 630: when the hydrogen peroxide concentration is less than a first concentration, the dosing frequency of the first dosing pump 240 is increased; when the hydrogen peroxide concentration is greater than or equal to the first concentration and less than the second concentration, the dosing frequency of the first dosing pump 240 remains unchanged; when the hydrogen peroxide concentration is greater than or equal to the second concentration, the dosing frequency of the first dosing pump 240 is decreased; wherein, the first concentration is less than the second concentration.

[0082] In this embodiment, the first concentration can be 0.2 mg / L and the second concentration can be 0.5 mg / L.

[0083] Through the above settings, the dosing frequency of the first dosing pump 240 can be adjusted in real time according to the hydrogen peroxide concentration during the operation of the air-cooled island's full life-cycle corrosion prevention system. Specifically, when the hydrogen peroxide concentration is low, the dosing frequency of the first dosing pump 240 is increased to rapidly raise the hydrogen peroxide concentration; when the hydrogen peroxide concentration is high, the dosing frequency of the first dosing pump 240 is decreased to allow the concentration to rise slowly. This setting achieves dynamic adjustment of the dosing frequency of the first dosing pump 240, effectively meeting the corresponding corrosion prevention requirements.

[0084] In summary, this application has at least the following advantages through the above settings: (1) The design of the sensing electrode 410 can accurately test the resistance of solutions with low conductivity; (2) By installing the sensing electrode 410 in situ, the corrosion rate monitoring module 400 can monitor the location of the main exhaust pipe 100 with the greatest corrosion in a timely and accurate manner, effectively preventing the corrosion of the air-cooled island; (3) Different anti-corrosion treatments are carried out on the entire service life of the air-cooled island, which can effectively inhibit the corrosion of the air-cooled island; (4) The entire process from drug preparation to drug addition is automated, which is simple to operate, requires no human intervention, and has a high degree of automation.

[0085] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

[0086] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the term "comprising" or any other variations thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0087] In the above embodiments, descriptions of directions such as "up", "down", and "side" are based on the accompanying drawings.

[0088] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A full life-cycle corrosion protection system for air-cooled islands, characterized in that, The system includes a hydrogen peroxide supply pipeline (200) and an ethanolamine supply pipeline (300), both connected to the main exhaust pipe (100). The hydrogen peroxide supply pipeline (200) is sequentially equipped with a hydrogen peroxide solution tank (230), a first dosing pump (240), and a hydrogen peroxide on / off valve (250). The ethanolamine supply pipeline (300) is sequentially equipped with an ethanolamine solution tank (330), a second dosing pump (340), and an ethanolamine on / off valve (350). The main exhaust pipe (100) is equipped with a corrosion rate monitoring module (400), which includes a sensing electrode (410) and a connection to the sensing electrode (410). 0) A corrosion rate monitoring instrument (420) with electrical connection, wherein the main exhaust pipe (100) is L-shaped, and the sensing electrode (410) is installed inside the main exhaust pipe (100) and located at its L-shaped bend; the outlet of the main exhaust pipe (100) is connected to the inlet of the air-cooled island (500), and the outlet of the air-cooled island (500) is connected to the fine treatment system (700) through the output pipeline (600), the output pipeline (600) is equipped with a condensate pump (610), and the output pipeline (600) is equipped with an online hydrogen conductivity meter (620) and a first online hydrogen peroxide meter (630) at the outlet of the condensate pump (610).

2. The air-cooled island full life-cycle corrosion protection system according to claim 1, characterized in that, The hydrogen peroxide supply pipeline (200) is also provided with a hydrogen peroxide storage tank (210) and a first metering pump (220) in sequence upstream of the hydrogen peroxide solution tank (230). The hydrogen peroxide solution tank (230) is provided with a first inlet (231), which is connected to the demineralized water tank (800) through a first water supply pipeline (260). The first water supply pipeline is provided with a first valve (270). The hydrogen peroxide solution tank (230) is provided with a second online hydrogen peroxide meter (280) for monitoring the internal hydrogen peroxide concentration. The ethanolamine supply pipeline (300) is further provided with an ethanolamine storage tank (310) and a second metering pump (320) upstream of the ethanolamine solution tank (330). The ethanolamine solution tank (330) is provided with a second inlet (331), which is connected to the demineralized water tank (800) through a second water supply pipeline (360). The second water supply pipeline is provided with a second valve (370). The ethanolamine solution tank (330) is provided with an online conductivity meter (380) for monitoring the internal ethanolamine concentration.

3. The air-cooled island full life-cycle corrosion protection system according to claim 2, characterized in that, The air-cooled island full life cycle corrosion protection system also includes a dilution water pump (900), the inlet of which is connected to the demineralized water tank (800), and the first water supply pipeline (260) and the second water supply pipeline (360) are both connected to the outlet of the dilution water pump (900).

4. The air-cooled island full life-cycle corrosion protection system according to claim 2, characterized in that, The first water inlet (231) is located at the top of the hydrogen peroxide solution tank (230), and the second water inlet (331) is located at the top of the ethanolamine solution tank (330).

5. The air-cooled island full life-cycle corrosion protection system according to claim 1, characterized in that, The corrosion rate monitoring module (400) further includes a hollow cylindrical shell (430), one end of which is a closed end and the other end of which is an open end. The shell (430) is fixedly disposed on the main exhaust pipe (100), with the closed end located inside the main exhaust pipe (100) and the open end located outside the main exhaust pipe (100). The sensing electrode (410) is fixedly disposed on the closed end and is connected to the corrosion rate monitor (420) via a wire (440), which is housed within the inner cavity of the shell (430).

6. The air-cooled island full life-cycle corrosion protection system according to claim 5, characterized in that, The sensing electrode (410) includes a working electrode (411) and an auxiliary electrode (412). Both the working electrode (411) and the auxiliary electrode (412) are fixedly disposed at the closed end. The working electrode (411) is directly opposite to the steam flow direction inside the main exhaust pipe (100). The auxiliary electrode (412) is disposed on the outer periphery of the working electrode (411) and is parallel to the steam flow direction inside the main exhaust pipe (100). The distance between the working electrode (411) and the auxiliary electrode (412) is 2 mm.

7. The air-cooled island full life-cycle corrosion protection system according to claim 5, characterized in that, The main exhaust pipe (100) has a threaded hole in its wall, and the housing (430) has an external thread (431) that is helically engaged with the threaded hole.

8. A method for corrosion prevention throughout the entire life cycle of an air-cooled island, characterized in that, Corrosion protection treatment using the full life-cycle corrosion protection system for air-cooled islands as described in any one of claims 1-7 includes the following steps: When the unit is started and stopped, disconnect the hydrogen peroxide on / off valve (250), open the ethanolamine on / off valve (350), and use the second dosing pump (340) to add ethanolamine from the ethanolamine solution tank (330) to the main exhaust pipe (100). When the unit is operating normally and the value monitored by the online hydrogen conductivity meter (620) is less than the set hydrogen conductivity, open the hydrogen peroxide on / off valve (250), close the ethanolamine on / off valve (350), and use the first dosing pump (240) to add hydrogen peroxide from the hydrogen peroxide solution tank (230) to the main exhaust pipe (100). When the unit is operating normally and the value monitored by the online hydrogen conductivity meter (620) is greater than or equal to the set hydrogen conductivity, disconnect the hydrogen peroxide on / off valve (250), open the ethanolamine on / off valve (350), and use the second dosing pump (340) to add ethanolamine from the ethanolamine solution tank (330) to the main exhaust pipe (100).

9. The full life-cycle corrosion prevention method for air-cooled islands according to claim 8, characterized in that, The step of adding ethanolamine from the ethanolamine solution tank (330) to the main exhaust pipe (100) using the second dosing pump (340) further includes using a corrosion rate monitoring module (400) to monitor the current corrosion rate of the main exhaust pipe (100): When the corrosion rate is greater than the first rate, increase the dosing frequency of the second dosing pump (340); When the corrosion rate is greater than the second rate and less than or equal to the first rate, the dosing frequency of the second dosing pump (340) remains unchanged; When the corrosion rate is less than or equal to the second rate, reduce the dosing frequency of the second dosing pump (340); The first speed is greater than the second speed.

10. The full life-cycle corrosion prevention method for air-cooled islands according to claim 8, characterized in that, The step of adding hydrogen peroxide from the hydrogen peroxide solution tank (230) to the main exhaust pipe (100) using the first dosing pump (240) further includes monitoring the hydrogen peroxide concentration using the first online hydrogen peroxide meter (630): When the hydrogen peroxide concentration is less than the first concentration, the dosing frequency of the first dosing pump (240) is increased; when the hydrogen peroxide concentration is greater than or equal to the first concentration and less than the second concentration, the dosing frequency of the first dosing pump (240) remains unchanged. When the hydrogen peroxide concentration is greater than or equal to the second concentration, reduce the dosing frequency of the first dosing pump (240); The first concentration is less than the second concentration.

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