Method and device for evaluating the corrosion prevention effect of boiler shutdown protection for thermal power generation units

Abstract

A method and apparatus for evaluating the anti-corrosion effect of boiler shutdown protection of a thermal power generation unit, the method including the steps of measuring a cumulative flow rate at a condensate pump outlet during a start-up phase of the unit, measuring the mass content of iron in steam associated with a boiler heat receiving surface during the start-up phase of the unit and calculating an average value of the iron content in the steam associated with the corresponding boiler heat receiving surface, calculating the total iron content during the start-up phase of the unit using a preset total iron content fitting equation based on the cumulative flow rate and the average iron content, and evaluating the anti-corrosion effect of boiler shutdown protection prior to the current start-up of the unit using the total iron content as an evaluation index.

Description

Cross-references to related applications

[0001] This application is filed based on a Chinese patent application having application number 202111327974.7 and filing date November 10, 2021, and claims priority to the Chinese patent application, the entire contents of which are incorporated by reference into this application. [Technical field]

[0002] This disclosure relates to a boiler Preventing corrosion in steam systems The present invention relates to a method and apparatus for evaluating the corrosion prevention effect of boiler shutdown protection in a thermal power generation unit. [Background technology]

[0003] In recent years, with the successive introduction of nuclear power, hydroelectric power, wind power and photovoltaic power generation units, thermal power generation units are faced with the strict control of operation time, longer and longer shutdown states and more and more start-up and shutdown times. Therefore, in order to avoid the occurrence of a large amount of corrosion during the shutdown period of the coal-fired boiler, ensure that the coal-fired boiler of the unit can be started safely and reliably at any time, and maintain normal, safe and stable operation for a long period of time, and avoid accidents such as pipe burst during the operation of the coal-fired boiler caused by corrosion during shutdown, the corrosion protection requirements for the shutdown protection of the coal-fired boiler of the thermal power generation unit are also becoming more and more stringent.

[0004] At present, there are many records in relevant standards about the corrosion prevention methods for shutdown protection of coal-fired boilers in thermal power generation units. However, there is no method for evaluating the corrosion prevention effect of shutdown protection of coal-fired boilers, so it is impossible to evaluate the corrosion prevention effect of shutdown protection of coal-fired boilers, and it is impossible to grasp the corrosion prevention situation of the huge coal-fired boiler steam system under shutdown protection state. It is impossible to express whether the adopted shutdown protection method of coal-fired boiler is reliable and trustworthy. Inappropriate shutdown protection will cause corrosion of the coal-fired boiler, creating a risk of pipe bursting during subsequent operation. Summary of the Invention

[0005] In order to solve the problems existing in the related art, the embodiments of the present disclosure provide a method and apparatus for evaluating the corrosion prevention effect of boiler shutdown protection of a thermal power unit, which is easy to operate and implement, and can effectively grasp the corrosion prevention situation in the piping of a huge coal-fired boiler steam system under boiler shutdown protection state, and judge whether the currently adopted coal-fired boiler shutdown protection method is reliable and effective.

[0006] In order to achieve the above objectives, the present disclosure provides the following technical solutions:

[0007] An embodiment of a first aspect of the present disclosure provides a method for evaluating anti-corrosion effect due to boiler shutdown protection of a thermal power generation unit, the method including the steps of: measuring a cumulative flow rate at an outlet of a condensate pump during a start-up phase of a unit; measuring a mass content of iron in steam associated with a boiler heat receiving surface during the start-up phase of the unit and calculating an average value of the iron content in the steam associated with the corresponding boiler heat receiving surface; calculating a total iron content during the start-up phase of the unit using a preset total iron content fitting equation based on the cumulative flow rate and the average iron content; and evaluating an anti-corrosion effect due to boiler shutdown protection before the current start-up of the unit using the total iron content as an evaluation index.

[0008] In some embodiments, the step of measuring the cumulative flow rate at the outlet of the condensate pump during the startup phase of the unit includes measuring a first cumulative flow rate of the unit during a phase from the start of steady-state operation after startup of the condensate pump to the end of thermal cleaning, and measuring a second cumulative flow rate of the unit during a phase from the start of rotation of the steam turbine rotor to the incorporation of the steam turbine into a power generation unit.

[0009] In some embodiments, measuring the mass iron content in the steam associated with the boiler heat receiving surface during the start-up phase of the unit includes measuring the iron content of the condensate, the iron content of the feedwater, the iron content of the boiler water or start-up separator effluent, and the iron content of the superheated steam.

[0010] In some embodiments, calculating an average iron content in the steam associated with the corresponding boiler heat receiving surface includes calculating the average iron content based on a mass content of the iron in the steam associated with the boiler heat receiving surface within a detection period.

[0011] In some embodiments, the preset total iron fitting equation is: M 総鉄量 =V 熱洗浄終了時 ×c 復水の鉄含有量平均値 +V 熱洗浄終了時 ×c 給水の鉄含有量平均値 +V 熱洗浄終了時 ×c ボイラ水又は起動分離器排水の鉄含有量平均値 +V 蒸気タービンのローター回転段階から併入まで ×c 過熱蒸気の鉄含有量平均値 , M 総鉄量 is the total iron content of the unit during the start-up phase, and V 熱洗浄終了時 is the first cumulative flow rate from the start of steady-state operation after the condensate pump is started to the end of thermal cleaning, and V 蒸気タービンのローター回転段階から併入まで is the second cumulative flow rate of the unit from the start of rotation of the steam turbine rotor to the joining of the steam turbine to the power generation unit, and c 復水の鉄含有量平均値 is the average iron content of the condensate, and c 給水の鉄含有量平均値 is the average iron content of the feed water, and c ボイラ水又は起動分離器排水の鉄含有量平均値 is the average iron content of the boiler water or the start-up separator wastewater, and c 過熱蒸気の鉄含有量平均値 is the average iron content of the superheated steam.

[0012] In some embodiments, the method for evaluating corrosion protection effectiveness of boiler outage protection of a thermal power unit further comprises adding ammonia to the condensate and adding ammonia to the feedwater during the start-up phase.

[0013] An embodiment of a second aspect of the present disclosure provides an evaluation device for evaluating anti-corrosion effect due to boiler shutdown protection of a thermal power generation unit, the device comprising: an iron content measurement module for measuring a cumulative flow rate at an outlet of a condensate pump during a startup phase of a unit; an iron content measurement module for measuring a mass content of iron in steam associated with the boiler heat receiving surface during the startup phase of the unit, the iron content measurement module including a calculation unit for calculating an average value of the iron content in the steam associated with a corresponding boiler heat receiving surface; a total iron content calculation module for calculating a total iron content during the startup phase of the unit using a preset total iron content fitting equation based on the cumulative flow rate and the average iron content; and an evaluation module for evaluating anti-corrosion effect due to boiler shutdown protection before the current startup of the unit using the total iron content as an evaluation index.

[0014] In some embodiments, the cumulative flow measurement module includes a first stage measurement module for measuring a first cumulative flow of the unit from the start of steady-state operation after the start of the condensate pump to the end of thermal cleaning, and a second stage measurement module for measuring a second cumulative flow of the unit from the start of rotation of the steam turbine rotor to the incorporation of a power generation unit into the steam turbine.

[0015] In some embodiments, the iron content measurement module comprises a first measurement module for measuring the iron content of the condensate, a second measurement module for measuring the iron content of the feedwater, a third measurement module for measuring the iron content of the boiler water or start-up separator effluent, and a fourth measurement module for measuring the iron content of the superheated steam.

[0016] In some embodiments, the apparatus for evaluating the corrosion prevention effect due to boiler shutdown protection of a thermal power unit further includes a device for adding ammonia to the condensate and a device for adding ammonia to the feedwater. Effect of the Invention

[0017] Compared with the related art, the present disclosure has the following beneficial effects: The embodiments of the present disclosure provide a method and device for evaluating the anti-corrosion effect of boiler shutdown protection of a thermal power unit, which can use any one of the boiler shutdown protection methods to protect the unit for a certain period of time, and then start up the unit to evaluate its anti-corrosion protection effect, which has a wide range of application. By measuring the cumulative flow rate at each stage of startup and the iron content of each steam system of the main heat-receiving surface of the coal-fired boiler and performing fitting calculation to obtain the corresponding total iron content in the system, the anti-corrosion situation of each steam system of the coal-fired boiler in shutdown protection can be very effectively represented, the data accuracy is high, the results are intuitive and clear, the device structure is simple, and the operation is easy to implement. The total iron content can be used to effectively grasp the anti-corrosion situation in the piping of the steam system of a huge coal-fired boiler in the boiler shutdown protection state, and can be used to judge whether the currently adopted coal-fired boiler shutdown protection method is reliable and effective, thereby avoiding the safety risks caused by corrosion due to the shutdown of the coal-fired boiler.

[0018] According to the embodiment of the present disclosure, ammonia is added to the condensate and ammonia is added to the feedwater at appropriate times during the start-up phase, and no precision treatment device is introduced during the current start-up process of the unit, thereby ensuring that the pH value of the feedwater is controlled within an appropriate range, i.e., the conductivity is controlled within a preferred range; for controlling steam by dosing during start-up and specifying precision treatment devices, the prerequisites can be standardized collectively to facilitate mutual comparison of the anti-corrosion effects of various coal-fired boiler shutdown protection methods and each coal-fired boiler shutdown protection; the change in the anti-corrosion effect of the same protection method with the change in shutdown time can be compared and observed to judge the sustainability of the protection; the protection effects of different protection methods during the same shutdown period can be compared to select a more preferred protection method, and the protection method can be further optimized, which is highly practicable. [Brief description of the drawings]

[0019] [Figure 1]1 is a process flow chart of an evaluation device according to an embodiment of the present disclosure. [Diagram 2] 1 is a flowchart of an evaluation method according to an embodiment of the present disclosure. [Diagram 3] 1 is a flowchart illustrating an evaluation method according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The present disclosure will be described in more detail below with reference to specific examples. The following examples are provided to interpret the present disclosure and are not intended to limit the present invention.

[0021] An embodiment of the present disclosure provides a method and device for evaluating the anti-corrosion effect of boiler shutdown protection of a thermal power unit based on detection data analysis of steam quality during cold start-up of a thermal power unit and test and research results, and the monitoring and control method represents the anti-corrosion effect of the coal-fired boiler shutdown protection using the total iron content in the drainage steam of each heat-receiving surface during the startup phase of the coal-fired boiler of the thermal power unit, and the lower the total iron content, the better the anti-corrosion effect of the coal-fired boiler shutdown protection.

[0022] Specifically, as shown in FIG. 2 , an embodiment of the present disclosure provides a method for evaluating the anti-corrosion effect of boiler shutdown protection of a thermal power generation unit, which includes the steps of: before the evaluation, selecting any one of the boiler shutdown protection methods to protect the unit for a preset boiler shutdown time; measuring the cumulative flow rate at the outlet of the condensate pump in the startup phase of the unit; measuring the mass content of iron in the steam associated with the boiler heat receiving surface in the startup phase of the unit and calculating the average iron content in the steam associated with the corresponding boiler heat receiving surface; calculating the total iron content in the startup phase of the unit through a preset total iron content fitting formula based on the cumulative flow rate and the average iron content; and evaluating the anti-corrosion effect of the boiler shutdown protection before the current startup of the unit using the total iron content as an evaluation index, wherein the higher the total iron content, the worse the anti-corrosion effect of the boiler shutdown protection method.

[0023] The method and apparatus for evaluating the anti-corrosion effect of boiler shutdown protection of a thermal power unit provided by the embodiments of the present disclosure can use any one of the boiler shutdown protection methods to protect the unit for a certain period of time, and then start up the unit to evaluate its anti-corrosion protection effect, which has a wide range of application. By measuring the cumulative flow rate at each stage of startup and the iron content of each steam system of the main heat-receiving surface of the coal-fired boiler and performing fitting calculations to obtain the corresponding total iron content in the system, the anti-corrosion situation of each steam system of the coal-fired boiler in shutdown protection can be very effectively represented, the data accuracy is high, the results are intuitive and clear, the device structure is simple, and the operation is easy to implement. The total iron content can be used to effectively grasp the anti-corrosion situation in the piping of the steam system of a huge coal-fired boiler under boiler shutdown protection, and can judge whether the currently adopted coal-fired boiler shutdown protection method is reliable and effective, thereby avoiding the safety risks caused by corrosion due to the shutdown of the coal-fired boiler.

[0024] As shown in FIG. 3, the step of measuring the cumulative flow rate at the outlet of the condensate pump during the startup phase of the unit further includes a step of measuring a first cumulative flow rate during a phase from the start of steady-state operation of the unit after startup of the condensate pump to the end of thermal cleaning, and a step of measuring a second cumulative flow rate during a phase from the start of rotation of the steam turbine rotor to the incorporation of the steam turbine into the power generation unit.

[0025] Specifically, the end of the thermal cleaning and the start of rotation of the rotor of the steam turbine are the same time.

[0026] Further, the step of measuring the iron content in the steam associated with the boiler heat receiving surface during the start-up phase of the unit includes the steps of measuring the iron content of the condensate, the iron content of the feedwater, the iron content of the boiler water or start-up separator effluent, and the iron content of the superheated steam.

[0027] In an embodiment of the present disclosure, the step of measuring the average iron content in the steam associated with the boiler heat receiving surface during the start-up phase of the unit includes the step of calculating an arithmetic average iron content based on the iron content in the steam associated with the boiler heat receiving surface within a detection period.

[0028] In some embodiments, the detection period may be 1 hour, 2 hours, 3 hours, etc., and the detection period is determined according to the actual situation.

[0029] In an embodiment of the present disclosure, calculating an average iron content based on the mass content of iron in the steam associated with the boiler heat receiving surface within a detection period includes calculating an average iron content of the condensate, an average iron content of the feedwater, an average iron content of the boiler water or start-up separator effluent, and an average iron content of the superheated steam.

[0030] In the embodiment of the present disclosure, the preset total iron fitting equation is as follows: M 総鉄量 =V 熱洗浄終了時 ×c 復水の鉄含有量平均値 +V 熱洗浄終了時 ×c 給水の鉄含有量平均値 +V 熱洗浄終了時 ×c ボイラ水又は起動分離器排水の鉄含有量平均値 +V 蒸気タービンのローター回転段階から併入まで ×c 過熱蒸気の鉄含有量平均値 , Here, M 総鉄量 is the total iron content of the unit at the start-up stage, and V 熱洗浄終了時 is the first cumulative flow rate from the start of steady-state operation after the condensate pump is started to the end of thermal cleaning, and V 蒸気タービンのローター回転段階から併入まで is the second cumulative flow rate of the unit from the start of rotation of the steam turbine rotor to the joining of the steam turbine to the power generation unit, and c 復水の鉄含有量平均値 is the average iron content of the condensate, and c 給水の鉄含有量平均値 is the average iron content of the feed water, and c ボイラ水又は起動分離器排水の鉄含有量平均値 is the average iron content of the boiler water or the start-up separator wastewater, and c 過熱蒸気の鉄含有量平均値 is the average iron content of the superheated steam.

[0031] Furthermore, the method for evaluating the corrosion prevention effect of boiler outage protection of a thermal power unit according to the embodiment of the present disclosure further includes the steps of adding ammonia to the condensate and adding ammonia to the feedwater during the start-up phase.

[0032] According to the embodiment of the present disclosure, ammonia is added to the condensate and ammonia is added to the feedwater at various times during the start-up phase, and no precision treatment device is introduced during the current start-up process of the unit, thereby ensuring that the pH value of the feedwater is controlled at 9.5±0.1, that is, the conductivity is controlled within the range of 6.8μS / cm to 10.8μS / cm; for the control of steam by dosing during start-up and the provision of precision treatment device, the preconditions can be standardized collectively to facilitate the mutual comparison of the anti-corrosion effects of various coal-fired boiler shutdown protection methods and each coal-fired boiler shutdown protection; the change in the anti-corrosion effect of the same protection method with the change in shutdown time can be compared and observed to judge the sustainability of the protection; the protection effects of different protection methods during the same shutdown period can be compared to select a more preferable protection method, and the protection method can be further optimized, which is highly practicable.

[0033] FIG. 1 is a process flow chart of an evaluation device according to an embodiment of the present disclosure. As shown in FIG. 1, the evaluation device for evaluating anti-corrosion effect by boiler shutdown protection of the thermal power generation unit may include: a selection module 100 for selecting any one of the boiler shutdown protection methods before evaluation to protect the unit for a preset boiler shutdown time; an accumulated flow measurement module 110 for measuring an accumulated flow rate at an outlet of a condensate pump in a start-up phase of the unit; an iron content measurement module 120 for measuring an iron mass content in steam associated with a boiler heat receiving surface in the start-up phase of the unit, the iron content measurement module 120 including a calculation unit for calculating an average iron content in steam associated with a corresponding boiler heat receiving surface; a total iron content calculation module 130 for calculating a total iron content in the start-up phase of the unit by a preset total iron content fitting formula based on the accumulated flow rate and the average iron content; and an evaluation module 140 for evaluating the anti-corrosion effect by boiler shutdown protection before the current start-up of the unit using the total iron content as an evaluation index.

[0034] In an embodiment of the present disclosure, the cumulative flow measurement module 110 includes a first stage measurement module 111 for measuring a first cumulative flow rate of the unit from the start of steady-state operation after the start of the condensate pump to the end of thermal cleaning, and a second stage measurement module 112 for measuring a second cumulative flow rate of the unit from the start of rotation of the steam turbine rotor to the incorporation of the steam turbine power generation unit.

[0035] In an embodiment of the present disclosure, the iron content measuring module 120 includes a first measuring module 121 for measuring the iron content of the condensate, a second measuring module 122 for measuring the iron content of the feedwater, a third measuring module 123 for measuring the iron content of the boiler water or the start-up separator effluent, and a fourth measuring module 124 for measuring the iron content of the superheated steam.

[0036] In an embodiment of the present disclosure, the calculation unit is further used to calculate an arithmetic mean value of the iron content based on the iron content in the steam associated with the boiler heat receiving surface within a detection period.

[0037] In an embodiment of the present disclosure, the apparatus for evaluating the corrosion prevention effect by boiler shutdown protection of a thermal power generation unit further includes a device for adding ammonia to condensate during operation and a device for adding ammonia to feed water.

[0038] The method and apparatus provided by the embodiments of the present disclosure specifically quantifies the evaluation of the anti-corrosion effect of shutdown protection of a coal-fired boiler of a thermal power unit, and the specific data of the total iron content finally obtained can be used to compare the anti-corrosion effects of each previous shutdown protection of the unit, which can be used to compare the anti-corrosion effects of different shutdown protection methods, and can also be adopted to compare the anti-corrosion effects of shutdown protection of the same type of unit, which is an evaluation method that allows direct comparison of data. In addition, the method and apparatus provided by the embodiments of the present disclosure have clearer and more specific requirements and monitoring for monitoring of steam quality during the unit startup process, and there are rules and systems to follow.

[0039] [Example 1] In this Example 1, a certain ultra-supercritical 660MW once-through boiler is selected, and boiler shutdown protection is performed for it, and the boiler shutdown protection method for the coal-fired boiler is performed by increasing the feedwater pH value. In a certain startup process, the evaluation method and device of the embodiment of the present disclosure are used to evaluate the corrosion prevention effect of coal-fired boiler shutdown protection at different boiler shutdown protection times. Specifically, in the startup process, the unit precision treatment high-speed mixed bed is not operated, and a device for adding ammonia to condensate and a device for adding ammonia to feedwater are operated, thereby maintaining the feedwater pH value between 9.5±0.1 and controlling the conductivity between 7.0μS / cm and 10.0μS / cm. Cold washDuring the entire start-up phase from ignition to unit inflow, indicators such as iron content in each steam sample are sampled and detected every two hours and at key times such as ignition, rotor start of rotation, and inflow, and the cumulative condensate flow rate is read and recorded by a cumulative flow meter installed at the outlet of the condensate pump until unit inflow.

[0040] In the first round, during the process of restarting the unit after 170 days of boiler shutdown protection, the measurement results obtained by the evaluation method of the embodiment of the present disclosure are as follows: at the end of thermal cleaning, the cumulative flow rate at the outlet of the condensate pump is 9014t, the average iron content of the condensate is 111.8μg / L, the average iron content of the feedwater is 82μg / L, the average iron content of the start-up separator discharge is 102.1μg / L; from the steam turbine rotor rotation stage to the combined flow, the cumulative flow rate at the outlet of the condensate pump is 3765t, the average iron content of the superheated steam is 30.3μg / L, and the total iron content calculated by the fitting formula provided by the embodiment of the present disclosure is 2781.3kg.

[0041] In the second round, during the process of the unit restarting after 8 days of boiler shutdown protection, the measurement results obtained by the evaluation method of the embodiment of the present disclosure are as follows: at the end of thermal cleaning, the cumulative flow rate at the outlet of the condensate pump is 7514t, the average iron content of the condensate is 24μg / L, the average iron content of the feedwater is 9.5μg / L, the average iron content of the start-up separator discharge is 12.5μg / L; from the steam turbine rotor rotation stage to the combined flow, the cumulative flow rate at the outlet of the condensate pump is 5327t, the average iron content of the superheated steam is 5.5μg / L, and the total iron content calculated by the fitting formula provided by the embodiment of the present disclosure is 375.0kg.

[0042] As can be seen from the evaluation, it is clear that the amount of corrosion during a long boiler shutdown period far exceeds the amount of corrosion during a short boiler shutdown period, which indicates that the method provided by the embodiment of the present disclosure can more intuitively recognize the corrosion prevention effect of shutdown protection, and the method of boiler shutdown protection can be improved based on this.

[0043] [Example 2] A 660MW ultra-supercritical coal-fired boiler in China is protected by filling nitrogen and increasing the pH value of the feedwater before and after each shutdown. During the startup process after the two shutdowns, this method is used to evaluate the corrosion prevention effect of the coal-fired boiler shutdown protection: during the startup process, the precision treatment high-speed mixed bed unit is not operated, and the device that adds ammonia to the condensate and the device that adds ammonia to the feedwater are operated to ensure that the feedwater pH is controlled between 9.5±0.1 and the conductivity is controlled between 7.0μS / cm~10.0μS / cm. Cold wash From the time of ignition to the time of unit inflow, indicators such as iron content in each steam and water sample are sampled and detected every two hours and at key times such as ignition, rotor start of rotation, and inflow, and at the same time, the cumulative condensate flow rate up to the time of unit inflow is recorded.

[0044] When the nitrogen filling protection method is adopted, the start-up process of the unit after about 179 days of boiler shutdown protection is as follows: at the end of thermal cleaning, the cumulative flow rate at the outlet of the condensate pump is 8173t, the average iron content of the condensate is 86.9μg / L, the average iron content of the feedwater is 71.3μg / L, the average iron content of the start-up separator discharge is 80.9μg / L, the cumulative flow rate at the outlet of the condensate pump from the steam turbine rotor rotation stage to the co-injection is 3019t, and the average iron content of the superheated steam is 26.1μg / L. The total iron content obtained by the fitting formula provided by this method is 2033.0kg.

[0045] When the protection method of increasing the pH value of the feedwater is adopted, the start-up process of the unit after 170 days of boiler shutdown protection is as follows: at the end of thermal cleaning, the cumulative flow rate at the outlet of the condensate pump is 9014t, the average iron content of the condensate is 111.8μg / L, the average iron content of the feedwater is 82μg / L, the average iron content of the start-up separator discharge is 102.1μg / L, the cumulative flow rate at the outlet of the condensate pump from the steam turbine rotor rotation stage to the co-injection stage is 3765t, and the average iron content of the superheated steam is 30.3μg / L. The total iron content obtained by the fitting formula provided by this method is 2781.3kg.

[0046] As can be seen from the evaluation results, it is clear that for the same unit, the corrosion amount when the boiler shutdown protection method of filling with nitrogen is adopted during the same boiler shutdown time is smaller than the corrosion amount when the boiler shutdown protection method of improving the feedwater pH value is adopted, which indicates that the boiler shutdown protection method of filling with nitrogen has a better anti-corrosion effect for boiler shutdown protection, and the method provided by the embodiment of the present disclosure can be used to compare the anti-corrosion effects of different boiler shutdown protection methods to select a more preferred boiler shutdown protection method.

[0047] What has been described above is merely a specific embodiment of the present disclosure, and the scope of protection of the present disclosure is not limited thereto. Any changes or replacements that do not deviate from the technical scope disclosed in the present disclosure can be easily thought of by a person skilled in the art, and all of these are included in the scope of protection of the present disclosure.

[0048] All embodiments of the present disclosure may be implemented independently or in conjunction with other embodiments, all of which are considered within the scope of what the present disclosure seeks to protect. [Explanation of symbols]

[0049] 100 Selection Module 110 Accumulative Flow Measurement Module 111 First stage measurement module 111 112 Second stage measurement module 120 Iron content measurement module 121 First Measurement Module 122 Second Measurement Module 123 3rd Measurement Module 124 4th Measurement Module 130 Total Iron Content Calculation Module 140 Evaluation Modules

Claims

1. measuring the cumulative flow rate at the outlet of the condensate pump during the start-up phase of the unit; measuring the iron mass content in the water and steam associated with the boiler heat receiving surface during the start-up phase of the unit and calculating the corresponding average iron content per unit volume in the water and steam associated with the boiler heat receiving surface; calculating a total iron content of the unit during the start-up phase based on the cumulative flow rate and the average iron content value through a preset total iron content fitting equation; Evaluating the corrosion prevention effect of the boiler shutdown protection before the current start-up of the unit using the total iron content as an evaluation index; A method for evaluating the corrosion prevention effect of boiler out-of-service protection of a thermal power generation unit, including:

2. Measuring the cumulative flow rate at the outlet of a condensate pump during a start-up phase of the unit, Measuring a first cumulative flow rate of the unit from the start of steady operation after the start of the condensate pump to the end of heated cleaning; measuring a second cumulative flow rate of the unit from the start of rotation of the rotor of the steam turbine to the joining of the steam turbine with the power generation unit; A method for evaluating a corrosion prevention effect by boiler shutdown protection of a thermal power generating unit according to claim 1, comprising:

3. Measuring the mass content of iron in water and steam associated with a boiler heat receiving surface during the start-up phase of the unit, 2. A method for evaluating the corrosion prevention effect of boiler shutdown protection of a thermal power unit as described in claim 1, comprising steps of measuring the iron content of condensate, the iron content of feedwater, the iron content of boiler water or steam separator effluent applied in the start-up phase, and the iron content of superheated steam.

4. calculating an average iron content per unit volume in the water and steam associated with the corresponding boiler heat receiving surface; The method for evaluating the corrosion prevention effect of boiler shutdown protection of a thermal power unit as described in claim 1, comprising a step of calculating the average iron content based on the mass content of the iron in the water and steam associated with the boiler heat receiving surface within a detection period.

5. The preset total iron amount fitting equation is as follows: M 総鉄量 = V at the end of heating and cleaning × c 復水の鉄含有量平均値 +V Heat cleaning completed ×c 給水の鉄含有量平均値 + V at the end of heating and cleaning x c Average iron content of boiler water or steam separator wastewater applied in the start-up phase + V 蒸気タービンのローター回転段階から併入まで ×c 過熱蒸気の鉄含有量平均値 , M 総鉄量 is the total iron content in the start-up stage of the unit, V is the first cumulative flow rate from the start of steady-state operation of the unit after the start of the condensate pump to the end of the heat cleaning, and V 蒸気タービンのローター回転段階から併入まで is the second cumulative flow rate of the unit from the start of rotation of the steam turbine rotor to the joining of the steam turbine to the power generation unit, and c 復水の鉄含有量平均値 is the average iron content of the condensate per unit volume, and c 給水の鉄含有量平均値 is the average iron content of the feedwater per unit volume, c is the average iron content of the boiler water or steam separator wastewater applied in the start-up phase per unit volume, c is the average iron content of the boiler water or steam separator wastewater applied in the start-up phase per unit volume, 過熱蒸気の鉄含有量平均値 The method for evaluating the corrosion prevention effect by boiler shutdown protection of a thermal power generating unit according to claim 1, wherein t is the average iron content of the superheated steam per unit volume.

6. 2. The method for evaluating the corrosion prevention effect of boiler outage protection of a thermal power unit according to claim 1, further comprising the steps of adding ammonia to the condensate and adding ammonia to the feed water during the start-up phase.

7. An apparatus for evaluating an anticorrosion effect by boiler shutdown protection of a thermal power generating unit, comprising: an accumulated flow measurement module for measuring an accumulated flow rate at the outlet of the condensate pump during the start-up phase of the unit; an iron content measurement module for measuring the iron mass content in the water and steam associated with the boiler heat receiving surface during the start-up phase of the unit, the iron content measurement module comprising a calculation unit for calculating an average iron content per unit volume in the water and steam associated with the corresponding boiler heat receiving surface; a total iron content calculation module for calculating a total iron content of the unit during the start-up phase according to the cumulative flow rate and the average iron content value through a preset total iron content fitting formula; an evaluation module for evaluating a corrosion prevention effect of the boiler shutdown protection before the current start-up of the unit using the total iron content as an evaluation index; The apparatus is provided for evaluating the corrosion prevention effect of protecting a thermal power generation unit by shutting down a boiler.

8. The cumulative flow measurement module includes: A first stage measurement module for measuring a first cumulative flow rate of the unit from the start of steady operation after the start of the condensate pump to the end of heating and cleaning; a second stage measurement module for measuring a second cumulative flow rate of the unit from the start of rotation of the rotor of the steam turbine to the joining of the steam turbine with the power generation unit; The apparatus for evaluating an anticorrosion effect by boiler shutdown protection of a thermal power generating unit according to claim 7 .

9. The iron content measurement module comprises: a first measurement module for measuring the iron content of the condensate; a second measurement module for measuring the iron content of the feedwater; a third measurement module for measuring the iron content of the boiler water or the steam separator effluent applied in the start-up phase; a fourth measurement module for measuring the iron content of the measured superheated steam; The apparatus for evaluating an anticorrosion effect by boiler shutdown protection of a thermal power generating unit according to claim 7 .

10. 8. The apparatus for evaluating the effect of corrosion prevention by boiler outage protection of a thermal power generating unit according to claim 7, further comprising a device for adding ammonia to condensate water and a device for adding ammonia to feed water.

Images