A device and method for measuring dissolved hydrogen content in high-temperature and high-pressure steam

Abstract

The present invention relates to a dissolved hydrogen content measuring device and method, and belongs to the field of monitoring. The present invention comprises a sampling and flow control unit, a sodium resin column, a stainless steel tee, an injection pump, a desalted water tank, a dissolved oxygen meter circulation pool, a palladium catalytic resin column, a dissolved oxygen meter and a programmable controller, the sampling and flow control unit comprises a sampling pipeline, a needle valve and a flow meter, the sodium resin column is connected to the sampling and flow control unit, the dissolved oxygen meter circulation pool comprises a dissolved oxygen meter circulation pool 1 and a dissolved oxygen meter circulation pool 2, one end of the stainless steel tee is connected to the sodium resin column, and the other two ends are respectively connected to the dissolved oxygen meter circulation pool 1 and the injection pump outlet, the other end of the injection pump is connected to the desalted water tank, the dissolved oxygen meter is connected to the dissolved oxygen meter circulation pool, and the injection pump is connected to the programmable controller. The present invention simultaneously measures the dissolved oxygen and dissolved hydrogen contents in the water sample, and the dissolved oxygen meter accurately measures to ensure the accuracy of the dissolved hydrogen measurement result, and the measurement result is not affected by dissolved oxygen.

Description

Technical Field

[0001] The present invention relates to a device and a method, in particular to a device and a method for measuring dissolved hydrogen content in high-temperature and high-pressure steam, and belongs to the technical field of over-temperature monitoring of tube walls of superheaters and reheaters in power plants. Background Art

[0002] For the metal materials of the heating surface that operate for a long time under actual working conditions, real-time and accurate monitoring of the high-temperature oxidation of the heating surface and controlling the oxidation rate of the steam meter in a safe state are the key technologies to prevent the explosion of the superheater and reheater. However, the high-temperature oxidation of the steam meter of the superheater and reheater is difficult to be monitored online, and its oxidation process can only be characterized by indirect measurement. The change in the dissolved hydrogen content in the steam can be used to measure the reaction rate between the high-temperature water vapor and the inner wall of the superheater and reheater. When the inner wall of the superheater and reheater is locally overheated or the oxide layer begins to scale due to overheating, the dissolved hydrogen content in the steam will increase significantly. The dissolved hydrogen content can reflect the actual situation of the high-temperature oxidation of the steam meter of the superheater and reheater, and is more sensitive than the wall temperature index and the steam temperature index. However, it was found in actual use that the measurement accuracy of the dissolved hydrogen meter was poor, especially when the boiler feed water was treated with oxygen, which greatly weakened the indication effect of dissolved hydrogen on the excessive wall temperature.

[0003] At present, the measurement of dissolved hydrogen in the main steam and reheat steam of power plants is mainly based on online dissolved hydrogen meters. The working principle of this instrument is similar to that of the dissolved oxygen meter, which is a test technology based on the potential-current method. Under the condition of a certain voltage, the current is linearly related to the dissolved hydrogen in the water sample. However, compared with the dissolved oxygen meter, the dissolved hydrogen meter using the potential-current method has no clear inspection and calibration, and the accuracy of the instrument measurement cannot be guaranteed.

[0004] At present, some manufacturers use the standard gas method to check and calibrate the dissolved oxygen meter, but it is found that the measurement value of the calibrated dissolved hydrogen meter has a large drift and poor reproducibility, which cannot meet the requirements of measuring low-content dissolved hydrogen. On the other hand, some manufacturers use the electrolysis method for inspection and calibration, but the consistency of electrolysis efficiency cannot be guaranteed, and the accuracy of standard water samples cannot be ensured. Therefore, this method is also very controversial and cannot meet actual requirements.

[0005] At present, some high-parameter and large-capacity generators are equipped with main steam or reheat steam dissolved hydrogen meters to achieve online monitoring of dissolved hydrogen, but the meters cannot be inspected and calibrated, and the validity of the measurement data cannot be guaranteed, which makes the meters lose their due role. On the other hand, it is found in the actual operation process that the measurement value of the dissolved hydrogen meter is significantly affected by the dissolved oxygen in the water sample, which is particularly prominent in some oxygenation units, resulting in large changes in the measurement value of the dissolved hydrogen meter, which cannot play the role of indicating that the wall temperature exceeds the standard.

[0006] A Chinese patent with a publication date of October 26, 2016 and a publication number of CN106053673A discloses an invention patent entitled "A method for determining the hydrogen content in water of a boiler system and its application". The patent includes: (1) sampling water from a boiler water vapor system to obtain a sample; (2) degassing the sample obtained in step (1) to collect a balance gas; (3) determining the volume of the balance gas, and using gas chromatography to determine the concentration of hydrogen in the balance gas obtained by degassing; (4) determining the solubility coefficient of hydrogen in water by degassing, and determining the original concentration of dissolved hydrogen in the water of the boiler system according to the solubility coefficient of hydrogen in water, the hydrogen concentration in the balance gas, the volume of the balance gas in step (2) and the volume of the sample obtained in step (1); the present invention also relates to the application of the above method. The invention uses gas chromatography to analyze dissolved hydrogen in water, which is different from the method used in the present application. Summary of the invention

[0007] The purpose of the present invention is to overcome the above-mentioned shortcomings in the prior art and to provide a device and method for measuring the dissolved hydrogen content in high-temperature and high-pressure steam. The device has a reasonable structural design and can simultaneously measure the dissolved oxygen and dissolved hydrogen contents in a water sample. Accurate measurement of the dissolved oxygen meter can ensure the accuracy of the dissolved hydrogen measurement result, and the measurement result is not affected by the dissolved oxygen.

[0008] The technical solution adopted by the present invention to solve the above-mentioned problem is: the device for measuring the content of dissolved hydrogen in high-temperature and high-pressure steam comprises a sampling and flow control unit for controlling the flow of a water sample to be measured, wherein the sampling and flow control unit comprises a sampling pipeline, a needle valve and a flow meter connected in sequence, and is characterized in that it also comprises a sodium resin column, a stainless steel tee, an injection pump, a desalted water tank, a dissolved oxygen meter circulation pool, a palladium catalytic resin column, a dissolved oxygen meter and a programmable controller, wherein the sodium resin column is connected to the sampling and flow control unit, and the dissolved oxygen meter circulation pool comprises a dissolved oxygen meter circulation pool 1 and a dissolved oxygen meter circulation pool 2. Second, one end of the stainless steel tee is connected to the sodium type resin column, and the other two ends are respectively connected to the dissolved oxygen meter circulation pool 1 and the injection pump outlet. The other end of the injection pump is connected to the desalted water tank. The dissolved oxygen meter is connected to the dissolved oxygen meter circulation pool through electrodes and electrode lines. The injection pump is connected to the programmable controller through a signal line. The palladium catalytic resin column is located between the two dissolved oxygen meter circulation pools. The water from the dissolved oxygen meter circulation pool 2 enters the unit drainage trough. The two dissolved oxygen electrodes share a transmitter. The transmitter and the injection pump are connected to the programmable controller through a signal line and receive control signals from the programmable controller.

[0009] Preferably, the sodium-type resin column of the present invention is a sodium-type cation exchange column, which is installed between the flow meter and the stainless steel tee. The exchange column is made of plexiglass, the sodium ion exchange resin is a macroporous color-changing resin, the length of the exchange column is not less than 0.6m, the water sample flow rate in the exchange column is not more than 18m / h, and an automatic exhaust valve is installed on the top of the exchange column.

[0010] Preferably, the palladium-catalyzed resin column of the present invention is installed between two dissolved oxygen circulation pools, the exchange column is made of organic glass, the length of the exchange column is not less than 0.6m, and the flow rate of the water sample in the exchange column is not more than 18m / h.

[0011] Preferably, the working error of the dissolved oxygen meter of the present invention is no more than 3.0 μg / L.

[0012] Preferably, the stainless steel tee and desalted water tank of the present invention are made of stainless steel, the volume of the desalted water tank is 100L, the injection pump comprises two independent infusion channels, the specification of the syringe is not less than 50mL, and the two infusion channels are automatically switched and filled with liquid through the control of a programmable controller.

[0013] Preferably, the present invention further comprises a high temperature rack temperature reducing and pressure reducing device, and the sampling pipeline lead-out position is located at the outlet of the high temperature rack temperature reducing and pressure reducing device.

[0014] Preferably, the sampling pipeline and the needle valve of the present invention are both made of stainless steel.

[0015] Preferably, the flow meter of the present invention is made of organic glass, and its measuring range is 0L / h-30L / h.

[0016] Preferably, the programmable controller of the present invention analyzes the dissolved hydrogen content according to the change value measured by the dissolved oxygen meter, and controls the start, stop and switch of the injection pump at the same time.

[0017] The present invention also provides a method for measuring the content of dissolved hydrogen in high-temperature and high-pressure steam, which adopts the device for measuring the content of dissolved hydrogen in high-temperature and high-pressure steam as described in any one of claims 1 to 9, and is characterized in that the steps are as follows: sampling is performed from the outlet of the temperature reducing and pressure reducing device of the high-temperature sampling rack, and the flow rate of the water sample is adjusted by a needle valve and a flow meter; after the water sample enters the sodium type resin column, ion exchange is performed, and ammonia in the water sample is completely removed, ensuring that ammonia poisoning will not occur in the subsequent palladium catalytic resin; at the stainless steel tee, an injection pump injects saturated oxygen desalted water in the desalted water tank into the water sample to increase the dissolved oxygen content of the water sample; when the oxygenated water sample flows through the palladium catalytic resin column, the dissolved oxygen and dissolved hydrogen in the water sample react under the catalytic action of the palladium resin; the dissolved oxygen meters before and after the palladium catalytic resin column detect the change in the dissolved oxygen content before and after the reaction; the programmable controller outputs the dissolved hydrogen content in the water sample according to the measured value of the dissolved oxygen meter, thereby indicating whether the current superheater and reheater are in an over-temperature state and giving a corresponding warning signal.

[0018] Compared with the prior art, the present invention has the following advantages and effects: (1) The present invention can simultaneously measure the dissolved oxygen and dissolved hydrogen contents in a water sample. The accuracy of the dissolved oxygen meter can ensure the accuracy of the dissolved hydrogen measurement result, and the measurement result is not affected by dissolved oxygen; (2) The dissolved oxygen meter is used as a monitoring instrument to analyze the dissolved hydrogen content by the change of the dissolved oxygen content before and after the palladium catalyzed resin column, which belongs to an indirect measurement method. Compared with the direct use of dissolved hydrogen meters, the measurement technology of dissolved oxygen meters is more mature, the measurement accuracy is higher, and the dissolved oxygen meters based on optical emission basically do not require maintenance; (3) Dissolved oxygen is used as the direct monitoring object. Dissolved oxygen and dissolved oxygen have a fixed relationship of 8:1 in the catalytic reaction. Therefore, when the dissolved oxygen content change value is used to analyze the dissolved hydrogen content, the error of dissolved hydrogen is smaller, only 1 / 8 of the measurement value of the dissolved oxygen meter; (4) Compared with dissolved hydrogen meters, dissolved oxygen meters currently have mature metrological calibration methods and standards, and are traceable. The dissolved hydrogen measurement results of this device are more reliable; (5) The measurement accuracy of the dissolved hydrogen meter is affected by the dissolved oxygen content in the water sample, but the dissolved hydrogen content measurement device in high-temperature and high-pressure steam described in this application is not affected by the dissolved oxygen content in the steam. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a system of a device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to an embodiment of the present invention.

[0020] In the figure: needle valve 1, flow meter 2, sodium type resin column 3, stainless steel tee 4, injection pump 5, desalted water tank 6, dissolved oxygen meter circulation pool 7, palladium catalytic resin column 8, sampling pipeline 9, dissolved oxygen meter 10, programmable controller 11, high temperature rack temperature and pressure reducer 12, unit drainage trough 13, dissolved oxygen meter circulation pool 1 71, dissolved oxygen meter circulation pool 2 72. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and by way of examples. The following examples are intended to explain the present invention but the present invention is not limited to the following examples.

[0022] Example

[0023] See also Figure 1The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam of this embodiment includes a sampling and flow control unit for controlling the flow of a water sample to be measured, a sodium resin column 3, a stainless steel tee 4, an injection pump 5, a desalted water tank 6, a dissolved oxygen meter circulation pool 7, a palladium catalytic resin column 8, a dissolved oxygen meter 10 and a programmable controller 11, the sampling and flow control unit includes a sampling pipeline 9, a needle valve 1 and a flow meter 2 connected in sequence, the sodium resin column 3 is connected to the sampling and flow control unit, the dissolved oxygen meter circulation pool 7 includes a dissolved oxygen meter circulation pool 1 71 and a dissolved oxygen meter circulation pool 2 72, and the stainless steel three One end of the tee 4 is connected to the sodium type resin column 3, the other end of the stainless steel tee 4 is connected to the dissolved oxygen meter circulation pool 1 71, one end of the injection pump 5 is connected to the stainless steel tee 4, the dissolved oxygen meter 10 is connected to the dissolved oxygen meter circulation pool 7, the desalted water tank 6 is connected to the injection pump 5, one end of the palladium catalyzed resin column 8 is connected to the dissolved oxygen meter circulation pool 1 71, the other end of the palladium catalyzed resin column 8 is connected to the dissolved oxygen meter circulation pool 2 72, the water from the dissolved oxygen meter circulation pool 2 72 flows into the unit drainage trough 13, and the programmable controller 11 is connected to the injection pump and the dissolved oxygen meter 10 through a signal line.

[0024] In this embodiment, the sampling pipe 9 is led out at the outlet of the high-temperature rack temperature reducer 12; the sampling pipe 9 and the needle valve 1 are both made of stainless steel; the flow meter 2 is made of organic glass, and its measuring range is 0L / h-30L / h.

[0025] The sodium-type resin column 3 in this embodiment is a sodium-type cation exchange column, which is mainly used to remove ammonia in water samples and prevent palladium-catalyzed resin poisoning. The sodium-type resin column 3 is installed after the flowmeter 2 and before the stainless steel tee 4. The exchange column is made of organic glass, and the sodium ion exchange resin is a macroporous color-changing resin. The length of the exchange column is not less than 0.6m, and the flow rate of the water sample in the exchange column is not more than 18m / h. An automatic exhaust valve is installed on the top of the exchange column.

[0026] In this embodiment, the palladium-catalyzed resin column 8 is responsible for catalyzing the reaction of dissolved hydrogen and dissolved oxygen. The palladium-catalyzed resin column 8 is installed between two dissolved oxygen circulation pools. The exchange column is made of organic glass, the length of the exchange column is not less than 0.6m, and the water sample flow rate in the exchange column is not more than 18m / h; the palladium-catalyzed resin in the exchange column is filled and compacted, and the water flow direction is bottom-in and top-out.

[0027] The dissolved oxygen meter 10 of this embodiment is an analysis and detection unit, which is suitable for measuring low-content dissolved oxygen in ultrapure water. The working error of the whole machine is required to be no more than 3.0 μg / L, and the measurement principle is based on an optical method.

[0028] In this embodiment, the stainless steel tee 4, injection pump 5 and desalted water tank 6 are auxiliary units of the measuring device, and are installed after the sodium resin column 3 and before the first dissolved oxygen sensor. The stainless steel tee 4 and the desalted water tank 6 are made of stainless steel. The volume of the desalted water tank 6 is about 100L. The injection pump 5 includes two independent infusion channels. The specification of the syringe is not less than 50mL. The two infusion channels can be automatically switched and filled by the programmable controller 11.

[0029] See also Figure 1 The water coming from the measuring device is the outlet water of the high temperature rack desuperheater 12, which is generally superheated steam or reheated steam after desuperheating and decompression. The water enters the needle valve 1 through the sampling pipe 9. The sampling pipe 9 is required to be made of stainless steel, but cannot contain hydrogen absorbing or hydrogen storage metals. The float flowmeter 2 is connected to the needle valve 1 to measure the water sample flow. The water sample flow is controlled to be about 20L / h by adjusting the opening of the needle valve 1.

[0030] After the water sample is adjusted in flow rate, it enters the sodium resin column 3, and all ammonia in the water sample is exchanged and removed, so as to prevent ammonia poisoning and loss of catalytic activity of the subsequent palladium catalytic resin column 8. There is an automatic exhaust valve at the top of the sodium resin column 3, which automatically removes bubbles in the water sample and eliminates the influence of bubbles on the measurement. The resin in the sodium resin column 3 adopts color-changing sodium ion exchange resin, and the state of the resin column can be judged according to the color change of the resin and the resin can be replaced in time.

[0031] In order to ensure that the dissolved oxygen content in the water sample meets the needs of complete reaction, it is necessary to ensure that the dissolved oxygen content in the water sample is at least 10 times the dissolved hydrogen content. However, in units without oxygen addition or using low oxygen treatment, the dissolved oxygen content of superheated steam or reheated steam is very low and cannot meet the requirements. Therefore, an auxiliary dosing unit is set to increase the dissolved oxygen content in the water sample. The auxiliary dosing unit consists of a dual-channel injection pump 5 and a desalted water tank 6. The volume of the desalted water tank 6 is about 100L. The injection pump 5 continuously adds saturated oxygen desalted water to the water sample to keep the dissolved oxygen content of the water sample at least 50μg / L. The auxiliary dosing unit is connected to the main measurement flow path through a stainless steel tee 4, and the channel switching of the dual-channel injection pump is jointly controlled by a programmable controller 11 and the injection pump 5.

[0032] After the water sample passes through the stainless steel tee 4 and is doped with medicine, it flows through the dissolved oxygen circulation pool 7 and the palladium catalytic resin column 8 in succession. Under the action of the palladium catalytic resin, the dissolved oxygen and dissolved hydrogen in the water sample react in a fixed ratio to generate water; due to the excessive dissolved oxygen content in the water sample, the dissolved hydrogen will react completely.

[0033] Two dissolved oxygen flow cells 7 are arranged at the inlet and outlet of the palladium catalytic resin column 8 to monitor the dissolved oxygen content of the water in and out of the palladium catalytic resin column 8 in real time.

[0034] The dissolved oxygen meter 10 of this embodiment adopts the optical measurement principle, and the dissolved oxygen circulation pool 7 is made of stainless steel; two dissolved oxygen electrodes share a dissolved oxygen meter transmitter, and the transmitter is connected to the programmable controller 11, and the two transmit signals and data with a 4-20mA current signal.

[0035] In this embodiment, the programmable controller 11 is connected to the dissolved oxygen meter 10 and the injection pump 5, and controls the switching and starting and stopping of the two channels of the injection pump 5 according to a predetermined program; the programmable controller 11 receives the measurement result of the dissolved oxygen meter 10 and calculates according to an internal formula to give the dissolved hydrogen content in the water sample, and then indicates whether the current superheater and reheater are in an over-temperature state according to the change trend of the dissolved hydrogen content and gives a corresponding warning signal.

[0036] The steps of measuring the dissolved hydrogen content in high-temperature and high-pressure steam in this embodiment are as follows: sampling is performed from the outlet of the high-temperature sampling rack temperature reducer and pressure reducer, and the flow rate of the water sample is adjusted by a needle valve 1 and a flowmeter 2; after the water sample enters the sodium resin column 3, ion exchange is performed, and ammonia in the water sample is completely removed, ensuring that the subsequent palladium catalytic resin will not be poisoned by ammonia; at the stainless steel tee 4, the injection pump 5 injects saturated oxygen desalted water in the desalted water tank 6 into the water sample to increase the dissolved oxygen content of the water sample; when the oxygenated water sample flows through the palladium catalytic resin column 8, the dissolved oxygen and dissolved hydrogen in the water sample react under the catalytic action of the palladium resin; the dissolved oxygen meter 10 before and after the palladium catalytic resin column 8 detects the change in the dissolved oxygen content before and after the reaction; the programmable controller 11 outputs the dissolved hydrogen content in the water sample according to the measured value of the dissolved oxygen meter 10, thereby indicating whether the current superheater and reheater are in an over-temperature state and giving a corresponding warning signal.

[0037] The entire measuring device of this embodiment can measure the dissolved oxygen and dissolved hydrogen content in high-temperature and high-pressure steam in real time, and timely reflect the over-temperature of the superheater and reheater tube walls; in the entire measuring device, the sampling pipeline 9, the needle valve 1 and the flow meter 2 constitute a sampling and flow control unit to ensure that the water sample flow is within a reasonable range; the sodium type resin column 3 is a pre-protection unit of the redox resin column, which mainly removes ammonia in the water sample to prevent the redox resin column from being poisoned by ammonia and losing its activity; the palladium catalytic resin column 8 is the core unit of the measuring device, which is responsible for catalyzing the reaction of dissolved hydrogen and dissolved oxygen; the stainless steel tee 4, the desalted water tank 6 The injection pump 5 is an auxiliary unit of the measuring device, which adds deionized water to the online water sample in real time to increase the dissolved oxygen content, ensure that the dissolved oxygen content in the water sample to be tested is not less than 10 times the dissolved hydrogen content, and ensure that the dissolved hydrogen reacts completely in the palladium catalytic resin column 8; the auxiliary unit composed of the deionized water tank 6 and the injection pump 5 is connected to the main measuring flow path through the stainless steel tee 4; the dissolved oxygen meter 10 is a detection unit of the measuring device, which analyzes and detects the changes of dissolved oxygen in the water sample before and after the redox resin column; the dissolved oxygen meter 10 is a monitoring instrument, and the instrument is a dual-channel configuration, connecting two dissolved oxygen electrodes and a dissolved oxygen circulation pool 7. The dissolved oxygen circulation pool 7 is located after the stainless steel tee 4 and the palladium catalytic resin column 8, respectively, and directly monitors the changes of dissolved oxygen content in the water sample before and after the palladium catalytic resin column 8; the programmable controller 11 is an analysis and control unit of the measuring device, and the programmable controller 11 can simultaneously receive the signals of the dissolved oxygen meter 10 and the injection pump 5, and analyze the dissolved hydrogen content in the water sample according to the measured value of the dissolved oxygen meter 10, thereby indicating whether the current superheater and reheater are in an over-temperature state and giving a corresponding warning signal. According to the signal of the injection pump 5, the programmable controller 11 controls the start, stop and switch of the two syringes of the injection pump 5 to ensure that the injection is in a real-time drug addition state.

[0038] The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam of this embodiment can be applied to monitoring dissolved hydrogen content in main steam, reheated steam and superheated steam in power plants, and can monitor overtemperature of superheater and reheater tube walls in real time, which plays an important early warning role in preventing tube bursts in superheaters and reheaters.

[0039] Through the above description, those skilled in the art can already implement it.

[0040] In addition, it should be noted that the shapes and names of the parts and components of the specific embodiments described in this specification may be different, and the above content described in this specification is only an example of the structure of the present invention. All equivalent changes or simple changes made based on the structure, features and principles described in the patent concept of the present invention are included in the protection scope of the patent of the present invention. Technicians in the technical field of the present invention can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A device for measuring dissolved hydrogen content in high-temperature and high-pressure steam, comprising a sampling and flow control unit for controlling the flow of a water sample to be measured, wherein the sampling and flow control unit comprises a sampling pipeline, a needle valve and a flow meter connected in sequence, characterized in that: It also includes a sodium resin column, a stainless steel tee, an injection pump, a desalted water tank, a dissolved oxygen meter circulation pool, a palladium catalytic resin column, a dissolved oxygen meter, a programmable controller and a high-temperature rack temperature and pressure reducer. The sodium resin column is connected to a sampling and flow control unit. The dissolved oxygen meter circulation pool includes a dissolved oxygen meter circulation pool 1 and a dissolved oxygen meter circulation pool 2. One end of the stainless steel tee is connected to the sodium resin column, and the other two ends are respectively connected to the dissolved oxygen meter circulation pool 1 and the injection pump outlet. The other end of the injection pump is connected to the desalted water tank. The dissolved oxygen meter is connected to the dissolved oxygen meter circulation pool through electrodes and electrode lines. The injection pump is connected to the programmable controller through a signal line. The palladium catalytic resin column is located between the two dissolved oxygen meter circulation pools. The water discharged from the dissolved oxygen meter circulation pool 2 enters the unit drainage tank. Two dissolved oxygen electrodes share a transmitter. The transmitter and the injection pump are connected to the programmable controller through a signal line and receive control signals sent by the programmable controller. The sampling pipeline lead-out position is located at the high-temperature rack temperature and pressure reducer outlet. The programmable controller analyzes the dissolved hydrogen content according to the measured change value of the dissolved oxygen meter and controls the start, stop and switch of the injection pump at the same time.

2. The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to claim 1, characterized in that: The sodium type resin column is a sodium type cation exchange column, which is installed between the flow meter and the stainless steel tee. The exchange column is made of plexiglass, the sodium ion exchange resin is a macroporous color-changing resin, the length of the exchange column is not less than 0.6m, the water sample flow rate in the exchange column is not more than 18m / h, and an automatic exhaust valve is installed on the top of the exchange column.

3. The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to claim 1, characterized in that: The palladium catalytic resin column is installed between two dissolved oxygen circulation pools. The material of the palladium catalytic resin column is organic glass. The length of the palladium catalytic resin column is not less than 0.6m. The flow rate of the water sample in the palladium catalytic resin column is not more than 18m / h.

4. The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to claim 1, characterized in that: The working error of the dissolved oxygen meter is no more than 3.0 μg / L.

5. The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to claim 1, characterized in that: The stainless steel tee and desalted water tank are made of stainless steel. The volume of the desalted water tank is 100L. The injection pump includes two independent infusion channels. The specification of the syringe is not less than 50mL. The two infusion channels are automatically switched and filled with liquid through the control of a programmable controller.

6. The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to claim 1, characterized in that: The sampling pipeline and the needle valve are both made of stainless steel.

7. The device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to claim 1, characterized in that: The flow meter is made of organic glass and has a measuring range of 0L / h-30L / h.

8. A method for measuring dissolved hydrogen content in high-temperature and high-pressure steam, using the device for measuring dissolved hydrogen content in high-temperature and high-pressure steam according to any one of claims 1 to 7, characterized in that: Here are the steps: Sampling is taken from the outlet of the high-temperature sampling rack and the temperature and pressure reducer, and the flow rate of the water sample is adjusted by a needle valve and a flow meter; after the water sample enters the sodium resin column, ion exchange is carried out, and ammonia in the water sample is completely removed to ensure that the subsequent palladium catalytic resin will not be poisoned by ammonia; at the stainless steel tee, the injection pump injects the saturated oxygen desalted water in the desalted water tank into the water sample to increase the dissolved oxygen content of the water sample; when the oxygenated water sample flows through the palladium catalytic resin column, the dissolved oxygen and dissolved hydrogen in the water sample react under the catalytic action of the palladium resin; The dissolved oxygen meters before and after the palladium catalytic resin column detect the change in dissolved oxygen content before and after the reaction; the programmable controller outputs the dissolved hydrogen content in the water sample based on the measured value of the dissolved oxygen meter, thereby indicating whether the current superheater and reheater are in an over-temperature state and giving a corresponding warning signal.

Images