A comprehensive anticorrosion method for a heat supply and heat storage tank during shutdown

Abstract

The application provides a comprehensive anticorrosion method for a heat supply and heat storage tank during a shutdown period, which comprises the following steps: opening a cold water isolation valve of the heat storage tank, injecting water into the heat storage tank, a heat storage tank water pipe, and a heat storage tank upper water distributor through a heat storage tank cold water pipe and a heat storage tank lower water distributor, storing heat in the heat storage tank, and discharging gas through a heat storage tank overflow pipe, a water seal tank, and a water seal tank overflow pipe; opening a nitrogen supply cutoff door, automatically starting a heat storage tank nitrogen supply self-adjusting valve, and replacing nitrogen at the top of the heat storage tank; opening a slow-release anticorrosive isolation door, adding a slow-release anticorrosive into heat supply circulating water, and releasing heat in the heat storage tank; keeping a high water level for isolation after the heat release in the heat storage tank is completed, locking the heat storage tank cold water isolation valve and the heat storage tank hot water isolation valve, and keeping water in the heat storage tank, which contains the slow-release anticorrosive, so that corrosion of the equipment in the water part of the heat storage tank can be prevented. Nitrogen is used for sealing, and due to the inertness of nitrogen, corrosion of the equipment at the top of the heat storage tank during the shutdown period can be prevented.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the technical field of heat storage tanks, and particularly relates to a comprehensive anticorrosion method for a heat supply heat storage tank during a shutdown period. BACKGROUND

[0002] In the process of high-quality heat supply, deep adjustment of a unit, peak-shaving of a unit, and repair of a unit and a heat supply device, a heat storage tank has become an indispensable part of a heat supply system and has been widely applied in a heat supply unit. If no anticorrosion work is performed, corrosion will occur in the heat storage tank during a 5-7 month shutdown period after a heat supply period, which will reduce the service life of the equipment, cause serious corrosion, and make the equipment unable to operate, thereby seriously affecting the safety of equipment operation. SUMMARY

[0003] The present application mainly provides a comprehensive anticorrosion method for a heat supply heat storage tank during a shutdown period to solve the technical problems in the background.

[0004] The present application solves the above technical problems by adopting the following technical solutions:

[0005] A comprehensive anticorrosion method for a heat supply heat storage tank during a shutdown period, comprising the following steps:

[0006] Step one, opening a cold water isolation valve of the heat storage tank, injecting water into the heat storage tank, a hot water pipe of the heat storage tank, and a water distributor above the heat storage tank through a cold water pipe of the heat storage tank and the water distributor below the heat storage tank, storing heat in the heat storage tank, and discharging gas through an overflow pipe of the heat storage tank, a water seal tank, and an overflow pipe of the water seal tank;

[0007] Step two, opening a nitrogen supply cutoff door, automatically opening a nitrogen supply self-regulating valve of the heat storage tank, and replacing nitrogen at the top of the heat storage tank, wherein, in the process, the purity of the nitrogen is observed, a water seal tank water supply valve is automatically opened, the water seal tank is automatically supplied with water to a required liquid level and then closed, and the pressure at the top of the heat storage tank is automatically closed when reaching 2 kpa;

[0008] Step three, opening a slow-release anticorrosive agent isolation door, adding a slow-release anticorrosive agent to heat supply circulating water, and releasing heat in the heat storage tank, wherein, in the process of releasing heat, the heat storage tank is replaced with the heat supply circulating water containing the slow-release anticorrosive agent, and a water seal is established to prevent nitrogen from overflowing outside;

[0009] Step four, keeping a high water level isolation after the heat release in the heat storage tank is completed, closing and locking the cold water isolation valve and the hot water isolation valve of the heat storage tank, and preventing corrosion of equipment in the water part of the heat storage tank by the slow-release anticorrosive agent.

[0010] Further, in step three, the water seal is established to prevent nitrogen from overflowing outside, comprising the following substeps:

[0011] The first step, in the process of heat storage tank heat release, the top steam of heat storage tank gradually cools down, the pressure of the top of heat storage tank drops to 1kpa, the heat storage tank nitrogen supply self-adjusting valve automatically opens, when the heat storage tank stops and reaches the ambient temperature, the nitrogen pressure of the heat storage tank is higher than 2kpa, the heat storage tank nitrogen supply self-adjusting valve automatically closes, and the nitrogen supply cut-off door is closed to maintain the pressure.

[0012] The second step, the water seal tank water supply valve is automatically put into operation to ensure the liquid level of the water seal tank to establish the water seal.

[0013] Further, in the second step, the required automatic water supply of the water seal tank to the required liquid level is 1.5m.

[0014] Further, in the second step, the required liquid level of the water seal tank is 1.5m.

[0015] Further, in the first step to the fourth step, the top end of the heat storage tank is connected with a heat storage tank cold water isolation valve, a heat storage tank nitrogen seal pressure gauge, a nitrogen purity detector and two heat storage tank breather valves, when the nitrogen pressure of the heat storage tank is-0.75-3kpa, the heat storage tank breather valve is automatically opened.

[0016] Further, in the first step to the fourth step, the bottom end of the heat storage tank is connected with a heat storage tank cold water pipe, the top end of the heat storage tank is connected with a heat storage tank hot water pipe, the gas inlet end of the heat storage tank is connected with a nitrogen supply pipe, and the heat storage tank is connected with the water seal tank through a heat storage tank overflow pipe.

[0017] Further, in the first step to the fourth step, the water outlet end of the water seal tank is connected with a water seal tank overflow pipe.

[0018] Further, in the first step to the fourth step, one end of the heat storage tank hot water pipe is connected with a water seal tank water supply pipeline, a water seal tank water supply valve is connected on the shell of the water seal tank water supply pipeline, and the water seal tank water supply valve is connected with the water seal tank.

[0019] Further, in the first step to the fourth step, a transmitter is connected on the shell of the heat storage tank hot water pipe.

[0020] Further, in the first step to the fourth step, a water seal tank liquid level switch and a slow-release preservative isolation door are sequentially connected on the shell of the heat storage tank cold water pipe.

[0021] Compared with the prior art, the beneficial effects of the present application are:

[0022] Firstly, the present application uses nitrogen sealing, which can prevent corrosion of the equipment at the top of the heat storage tank during the stop period due to the inertness of nitrogen.

[0023] Secondly, the application proposes to configure a water seal groove at the lower part of the overflow pipe of the heat storage tank, which can seal the nitrogen gas at the top and prevent the high-temperature water vapor from overflowing, and a water supplement device is configured to prevent the water in the water seal groove from evaporating and failing to maintain the liquid level, so as to achieve the sealing effect.

[0024] Thirdly, the application proposes a hot-state positive pressure nitrogen filling and corrosion prevention method, when the heat storage tank is in a hot state (storing water at 90-98 DEG C), the water vapor at the top of the heat storage tank is replaced by nitrogen gas and a positive pressure is maintained, and after the heat storage tank is cooled and stopped, the water vapor is condensed and only nitrogen gas is left, so that the purity of the nitrogen gas can be maintained and a micro-positive pressure isolation can be maintained, thereby improving the corrosion prevention effect.

[0025] Fourthly, the application proposes to add a slow-release corrosion inhibitor into the heating circulating water before the heat storage tank is cooled, and the water in the tank is replaced by the heating circulating water with the slow-release corrosion inhibitor during the cooling process, so that a high water level isolation can be maintained after the tank is stopped to prevent corrosion, thereby saving the loss of the stored water (≥25,000 tons) in the heat storage tank and effectively preventing corrosion.

[0026] The application will be described in detail below in combination with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The figure is a structural schematic diagram of the application.

[0028] In the figure: 10, heat storage tank; 11, heat storage tank cold water isolation valve; 12, heat storage tank breather valve; 13, heat storage tank nitrogen seal pressure gauge; 14, nitrogen purity detector; 20, water seal groove; 30, heat storage tank cold water pipe; 31, slow-release corrosion inhibitor isolation door; 32, water seal groove liquid level switch; 40, heat storage tank hot water pipe; 41, transmitter; 50, heat storage tank overflow pipe; 60, water seal groove water supplement pipeline; 61, water seal groove water supplement valve; 70, nitrogen supply pipe; 71, nitrogen supply cut-off door; 72, heat storage tank nitrogen supply self-adjusting valve; 80, water seal groove overflow pipe. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the application, the application will be described more fully below in combination with the related drawings, and several embodiments of the application are given in the drawings, but the application can be realized in different forms and is not limited to the embodiments described in the text, on the contrary, these embodiments are provided to make the disclosed content of the application more thorough and comprehensive.

[0030] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can be a middle element, and when an element is referred to as being "connected to" another element, it can be directly connected to the other element or there can be a middle element, and the terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for illustrative purposes.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. The use herein of the terms "including", "comprising", "having" and the like are meant to encompass the items listed thereafter as well as other items.

[0032] Embodiments, please refer to the attached Figure 1 A comprehensive corrosion prevention method for heat storage tank during shutdown period, comprising the following steps:

[0033] Step one, open the cold water isolation valve 11 of the heat storage tank, inject water into the heat storage tank 10, heat storage tank hot water pipe 40, heat storage tank upper water distributor through the heat storage tank cold water pipe 30 and heat storage tank lower water distributor, store heat in the heat storage tank 10, and exhaust through the heat storage tank overflow pipe 50, water seal tank 20 and water seal tank overflow pipe 80;

[0034] Step two, open the nitrogen supply cutoff door 71, and automatically open the heat storage tank nitrogen supply self-regulating valve 72, replace the nitrogen at the top of the heat storage tank 10, and observe the purity of nitrogen in the process. The water seal tank water supply valve 61 is automatically opened, and the water seal tank 20 is automatically filled to the required liquid level and then closed. The pressure at the top of the heat storage tank 10 reaches 2kpa and is automatically closed;

[0035] Step three, open the slow-release corrosion inhibitor isolation door 31, and add slow-release corrosion inhibitor to the heat supply circulating water. The heat storage tank 10 releases heat, and in the process of releasing heat, the heat storage tank 10 is replaced with heat supply circulating water containing slow-release corrosion inhibitor, and a water seal is established to prevent nitrogen from overflowing;

[0036] Step four, after the heat release of the heat storage tank 10 is completed, keep the high water level isolation, close the heat storage tank cold water isolation valve 11 and the heat storage tank hot water isolation valve, and the part of the heat storage tank 10 with water contains slow-release corrosion inhibitor, which can prevent corrosion of the equipment in the part of the heat storage tank 10 with water.

[0037] Further, in step three, the water seal is established to prevent nitrogen from overflowing, which comprises the following sub-steps:

[0038] First, during the heat release process of the heat storage tank 10, the steam at the top of the heat storage tank 10 gradually cools down, and the pressure at the top of the heat storage tank 10 drops to 1kpa. The heat storage tank nitrogen supply self-regulating valve 72 is automatically opened, and when the heat storage tank 10 is stopped and reaches the ambient temperature, the nitrogen pressure of the heat storage tank 10 is higher than 2kpa. The heat storage tank nitrogen supply self-regulating valve 72 is automatically closed, and the nitrogen supply cutoff door 71 is closed to maintain the pressure;

[0039] Second, the water seal tank water supply valve 61 is automatically opened to ensure the liquid level of the water seal tank 20 to establish a water seal;

[0040] Further, in the second step, the required liquid level of the water seal tank 20 is 1.5 m;

[0041] Further, in the second step, the required liquid level of the water seal tank 20 is 1.5 m;

[0042] Further, in the first step to the fourth step, the top end of the heat storage tank 10 is connected with a heat storage tank cold water isolation valve 11, a heat storage tank nitrogen sealing pressure gauge 13, a nitrogen purity detector 14 and two heat storage tank breather valves 12, when the nitrogen pressure of the heat storage tank 10 is-0.75-3kpa, the heat storage tank breather valve 12 is automatically opened, it needs to be explained that in the embodiment, the top pressure of the heat storage tank 10 is monitored through the heat storage tank nitrogen sealing pressure gauge 13, and the nitrogen concentration of the top of the heat storage tank 10 is monitored through the nitrogen purity detector 14;

[0043] Further, in the first step to the fourth step, the bottom end of the heat storage tank 10 is connected with a heat storage tank cold water pipe 30, the top end of the heat storage tank 10 is connected with a heat storage tank hot water pipe 40, the gas inlet end of the heat storage tank 10 is connected with a nitrogen supply pipe 70, and the heat storage tank 10 is connected with the water seal tank 20 through a heat storage tank overflow pipe 50;

[0044] Further, in the first step to the fourth step, the water outlet end of the water seal tank 20 is connected with a water seal tank overflow pipe 80;

[0045] Further, in the first step to the fourth step, one end of the heat storage tank hot water pipe 40 is connected with a water seal tank water supplement pipe 60, the shell of the water seal tank water supplement pipe 60 is connected with a water seal tank water supplement valve 61, and the water seal tank water supplement valve 61 is connected with the water seal tank 20;

[0046] Further, in the first step to the fourth step, the shell of the heat storage tank hot water pipe 40 is connected with a transmitter 41;

[0047] Further, in the first step to the fourth step, the shell of the heat storage tank cold water pipe 30 is sequentially connected with a water seal tank liquid level switch 32 and a slow-release preservative isolation door 31.

[0048] The specific operation mode of the application is as follows:

[0049] The heat storage tank cold water isolation valve 11 is opened, water is injected into the heat storage tank 10, the heat storage tank hot water pipe 40, the heat storage tank upper water distributor through the heat storage tank cold water pipe 30 and the heat storage tank lower water distributor, the heat storage tank 10 stores heat, and exhaust gas is discharged through the heat storage tank overflow pipe 50, the water seal tank 20 and the water seal tank overflow pipe 80;

[0050] When the nitrogen supply gate 71 is opened, the heat storage tank nitrogen supply self-regulating valve 72 is automatically opened, nitrogen is filled and replaced at the top of the heat storage tank 10. During this process, the purity of the nitrogen is observed, the water seal tank water supply valve 61 is automatically opened, the water seal tank 20 is automatically supplied with water to the required level, and then closed. When the pressure at the top of the heat storage tank 10 reaches 2 kPa, it is automatically closed.

[0051] The slow-release preservative isolation door 31 is opened, slow-release preservatives are added to the heat supply circulating water, and the heat storage tank 10 is discharged. During the heat discharge process, the tank is replaced with heat supply circulating water containing slow-release preservatives, and a water seal is established to prevent nitrogen from overflowing.

[0052] When the heat discharge of the heat storage tank 10 is completed, the high water level isolation is maintained, the heat storage tank cold water isolation valve 11 and the heat storage tank hot water isolation valve are closed and locked. The water in the tank contains slow-release preservatives, which can prevent corrosion of the equipment in the water part of the heat storage tank 10.

[0053] The above describes the application by way of example with reference to the accompanying drawings. It is clear that the specific implementation of the application is not limited by the above method. Any non-essential improvement or direct application of the inventive concept and technical solution to other occasions is within the scope of protection of the application.

Claims

1. A comprehensive anticorrosion method for heat supply heat storage tanks during shutdown, characterized in that, It comprises the following steps: Step one, open the cold water isolation valve (11) of the heat storage tank, inject water into the heat storage tank (10), the lower water distributor of the heat storage tank, the heat storage tank water pipe (40) and the upper water distributor of the heat storage tank through the heat storage tank cold water pipe (30), store heat in the heat storage tank (10), and exhaust through the overflow pipe (50) of the heat storage tank, the water seal tank (20) and the overflow pipe (80) of the water seal tank; Step two, open the nitrogen supply gate (71), and automatically open the heat storage tank nitrogen supply self-adjusting valve (72) to replace the nitrogen in the top of the heat storage tank (10). During this process, observe the purity of nitrogen, and automatically open the water seal tank water supply valve (61). After the water seal tank (20) is automatically filled with water to the required liquid level, it is closed. When the pressure in the top of the heat storage tank (10) reaches 2kpa, it is automatically closed; Step three, open the slow-release preservative isolation door (31), add slow-release preservative to the heat supply circulating water, and release heat in the heat storage tank (10). During the heat release process, replace the water in the tank with heat supply circulating water containing slow-release preservative, and establish a water seal to prevent nitrogen from overflowing; Step four, after the heat release in the heat storage tank (10) is completed, keep the high water level isolation, close the heat storage tank cold water isolation valve (11) and the heat storage tank hot water isolation valve, and the part of the tank with water contains slow-release preservative, which can prevent corrosion of the equipment in the heat storage tank (10).

2. The method according to claim 1, wherein the method is characterized by, In step three, the water seal is established to prevent nitrogen from overflowing, which comprises the following sub-steps: First, during the heat release process of the heat storage tank (10), the steam in the top of the heat storage tank (10) gradually cools down, the pressure in the top of the heat storage tank (10) drops to 1kpa, the heat storage tank nitrogen supply self-adjusting valve (72) is automatically opened, and when the heat storage tank (10) is stopped and reaches the ambient temperature, the nitrogen pressure in the heat storage tank (10) is higher than 2kpa, the heat storage tank nitrogen supply self-adjusting valve (72) is automatically closed, and the nitrogen supply gate (71) is closed to maintain the pressure; Second, the water seal tank water supply valve (61) is automatically opened to ensure the liquid level of the water seal tank (20) to establish a water seal.

3. The method according to claim 1, wherein the method is characterized by, In step two, the required automatic water filling of the water seal tank (20) to the required liquid level is 1.5m.

4. The method according to claim 2, wherein the method is characterized by, In the second step, the required liquid level of the water seal tank (20) is 1.5m.

5. The method according to claim 1, wherein the method is characterized by, In steps one to four, the top end of the heat storage tank (10) is connected with the heat storage tank cold water isolation valve (11), the heat storage tank nitrogen seal pressure gauge (13), the nitrogen purity detector (14) and two heat storage tank breather valves (12). When the nitrogen pressure in the heat storage tank (10) is between -0.75 and 3kpa, the heat storage tank breather valve (12) is automatically opened.

6. The method according to claim 1, wherein the method is characterized by, In steps one to four, the bottom end of the heat storage tank (10) is connected with the heat storage tank cold water pipe (30), the top end of the heat storage tank (10) is connected with the heat storage tank hot water pipe (40), the gas inlet end of the heat storage tank (10) is connected with the nitrogen supply pipe (70), and the heat storage tank (10) is connected with the water seal tank (20) through the heat storage tank overflow pipe (50).

7. The method according to claim 1, wherein the method is characterized by, In steps one to four, the water outlet end of the water seal tank (20) is connected with the water seal tank overflow pipe (80).

8. The method according to claim 1, wherein the method is characterized by, In the steps one to four, one end of the hot water pipe (40) of the heat storage tank is connected with a water seal tank water supplement pipeline (60), a shell of the water seal tank water supplement pipeline (60) is connected with a water seal tank water supplement valve (61), and the water seal tank water supplement valve (61) is connected with the water seal tank (20).

9. The method according to claim 1, wherein the method is characterized by, In the steps one to four, a transmitter (41) is connected with the shell of the hot water pipe (40) of the heat storage tank.

10. The method according to claim 1, wherein the method is characterized by, In the steps one to four, a water seal tank liquid level switch (32) and a slow-release preservative isolation door (31) are connected with the shell of the cold water pipe (30) of the heat storage tank in sequence.

Images