Generator hydrogen dehumidification device and isolation method

Abstract

The invention relates to the technical field of hydrogen cooling systems of generator sets, and provides a hydrogen dehumidification device of a generator, which comprises: a, an inlet for receiving hydrogen; b, an outlet for discharging the treated hydrogen; the internal structure is used for reducing the humidity of the hydrogen when the hydrogen flows through the internal structure; the isolation system is used for overhauling an isolation device under the condition of no shutdown; e. A control system for monitoring and controlling the flow of hydrogen and the operating state of the device; the control system comprises: i. A pressure monitoring unit for monitoring the pressure of the inlet and the outlet; ii. A temperature monitoring unit for monitoring the temperature of hydrogen; iii. A flow control unit for adjusting the flow of hydrogen; iv, a safety interlocking device; the isolation system comprises: i, a valve for controlling the inlet and outlet of hydrogen; ii. A gas replacement unit; and iii. A maintenance interface. By means of the technical scheme, the problems that in the related technology, the workload is large, and hydrogen is wasted are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen cooling systems of thermal power units, and in particular relates to an isolation method for a hydrogen dehumidification device. Background Art

[0002] Excessive water content in hydrogen will cause many adverse effects on the generator. Usually, a dedicated hydrogen dryer is installed outside the generator. Its hydrogen inlet pipeline is connected to the high-pressure side of the rotor fan, and its hydrogen return pipeline is connected to the low-pressure side of the fan, so that the hydrogen inside the generator can continuously flow into the dryer to obtain dry hydrogen. When the hydrogen dehumidification device fails, it cannot be directly disassembled for maintenance because there is hydrogen inside. When it is directly disassembled, the internal hydrogen will contact the external air, which may cause a hydrogen explosion accident. Generally, the hydrogen dehumidification device can only be repaired after the generator is shut down and the entire hydrogen cooling system is replaced with hydrogen.

[0003] However, failure of the hydrogen dehumidification device will cause the hydrogen humidity to exceed the standard, further leading to reduced insulation of the generator rotor and even grounding accidents. When this happens, hydrogen can only be frequently discharged and replenished, and new dry hydrogen must be used to replace the humid hydrogen, which is labor-intensive and results in waste of hydrogen. Summary of the invention

[0004] The present invention provides an isolation method for a hydrogen dehumidification device of a generator, which solves the problems of large workload and waste of hydrogen in the related art.

[0005] The technical solution of the present invention is as follows:

[0006] A generator hydrogen dehumidification device, comprising:

[0007] a. an inlet for receiving hydrogen;

[0008] b. an outlet for discharging the treated hydrogen;

[0009] c. an internal structure for reducing the humidity of hydrogen gas as it flows through;

[0010] d. An isolation system for isolating the unit for maintenance without stopping the machine;

[0011] e. a control system for monitoring and controlling the flow of hydrogen and the operating status of the device;

[0012] The control system comprises:

[0013] i. a pressure monitoring unit for monitoring the pressure of the inlet and the outlet;

[0014] ii. A temperature monitoring unit for monitoring the temperature of hydrogen;

[0015] iii. A flow control unit, used to adjust the flow of hydrogen;

[0016] iv. Safety interlock device to automatically cut off the hydrogen supply when an abnormal situation is detected;

[0017] The isolation system comprises:

[0018] i. One or more valves for controlling the inlet and outlet of hydrogen;

[0019] ii. A gas replacement unit to safely replace hydrogen with other gases before maintenance;

[0020] iii. A maintenance interface to allow maintenance personnel to safely enter the interior of the unit after isolation system operation.

[0021] A method for isolating a generator hydrogen dehumidification device, using the generator hydrogen dehumidification device according to claim 1, comprising:

[0022] S1. Work preparation: Use copper tools to perform all maintenance and operation operations, and check that there is no hot work in the turbine room;

[0023] S2, system isolation: shut down the generator hydrogen dehumidification device, close the inlet and outlet, isolate and shut down the temperature detection unit;

[0024] S3, dehumidification device gas replacement: adjust the gas replacement unit, and perform gas replacement through the replacement inlet door and the replacement outlet door;

[0025] S4. Dehumidification device maintenance: maintenance personnel perform maintenance on the dehumidification device through the maintenance interface;

[0026] S5. System recovery and startup: After confirming that the maintenance and replacement are completed, open the valve of the hydrogen dehumidification device and start the hydrogen dehumidification device.

[0027] Optionally, the step S1 also includes closely monitoring the pressure inside the generator through the pressure detection unit during the replacement process, and strictly prohibiting carbon dioxide from entering the generator.

[0028] Optionally, the step S2 further includes closing all gas supply valves related to the hydrogen dehumidification device. In the step S2, it is also necessary to open the sewage discharge door at the outlet of the hydrogen dehumidification device to perform a dead corner discharge operation. In the step S2, the pressure formula for adjusting the hydrogen dehumidification device is:

[0029] P adj -P current +ΔP, where P adj is the adjusted pressure, P current is the current pressure, and ΔP is the pressure adjustment value determined according to the safety operation standard.

[0030] Optionally, the step S3 further includes adjusting the carbon dioxide bus pressure reducing valve to ensure that the pressure after the pressure reducing valve is about 0.6 MPa. The formula for calculating the carbon dioxide flow in the step S3 is:

[0031] in is the carbon dioxide flow rate, V inlet is the carbon dioxide inlet volume flow rate, A inlet is the carbon dioxide inlet cross-sectional area.

[0032] Optionally, the step S3 further comprises repeatedly performing the opening and closing operation of the valve at the replacement outlet ten times. In the step S3, the temperature formula for detecting and controlling the carbon dioxide is:

[0033] T outlet =T inlet +ΔT, where T outlet is the outlet temperature of carbon dioxide, T inlet is the carbon dioxide inlet temperature, and ΔT is the temperature increased by the heating device.

[0034] Optionally, step S5 also includes detecting whether the hydrogen pressure and purity in the generator are qualified by a pressure detection unit.

[0035] Optionally, in step S4, the formula for evaluating the purity of hydrogen is:

[0036] in, is the hydrogen purity percentage, is the actual measured hydrogen concentration, C min is the minimum acceptable hydrogen concentration, C max The highest hydrogen concentration.

[0037] Optionally, in step S5, the formula for calculating the regeneration time of the hydrogen dehumidification device is:

[0038] Among them, t regencrate is the regeneration time, V touer is the volume of the absorption tower of the dehumidification device, C regen is the carbon dioxide concentration required for regeneration, F regen is the carbon dioxide regeneration flow rate.

[0039] Optionally, in step S5, the dead angle removal time of the hydrogen dehumidification device is calculated as follows:

[0040] where t purge is the dead angle time, V dcad is the dead space volume of the dehumidification device, F purgeis the hydrogen flow rate when exhausting dead corners.

[0041] The working principle and beneficial effects of the present invention are:

[0042] In the present invention, the online isolation and maintenance of the hydrogen dehumidification device can be realized, which avoids the untimely shutdown of the unit, reduces the loss of hydrogen due to frequent exhaust and replenishment, and enhances the safety and economic benefits of the unit operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The preferred implementation modes will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present invention.

[0044] Figure 1 This is a schematic diagram of the structure of the hydrogen dehumidification device of the present invention;

[0045] Figure 2 This is the hydrogen cooling system of the present invention. DETAILED DESCRIPTION

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0047] In order to simplify the drawings, only the parts related to the invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically shown, or only one of them is marked. In this article, "one" not only means "only one", but also means "more than one", and "several" includes "two" and "more than two".

[0048] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0050] Reference Figure 1 and Figure 2 , is an embodiment of the present invention, and proposes

[0051] A generator hydrogen dehumidification device, comprising:

[0052] a. an inlet for receiving hydrogen;

[0053] b. an outlet for discharging the treated hydrogen;

[0054] c. an internal structure for reducing the humidity of hydrogen gas as it flows through;

[0055] d. An isolation system for isolating the unit for maintenance without stopping the machine;

[0056] e. a control system for monitoring and controlling the flow of hydrogen and the operating status of the device;

[0057] The control system comprises:

[0058] i. a pressure monitoring unit for monitoring the pressure of the inlet and the outlet;

[0059] ii. A temperature monitoring unit for monitoring the temperature of hydrogen;

[0060] iii. A flow control unit, used to adjust the flow of hydrogen;

[0061] iv. Safety interlock device to automatically cut off the hydrogen supply when an abnormal situation is detected;

[0062] The isolation system comprises:

[0063] i. One or more valves for controlling the inlet and outlet of hydrogen;

[0064] ii. A gas replacement unit to safely replace hydrogen with other gases before maintenance;

[0065] iii. A maintenance interface to allow maintenance personnel to safely enter the interior of the unit after isolation system operation.

[0066] A method for isolating a generator hydrogen dehumidification device, using the generator hydrogen dehumidification device, comprising:

[0067] S1. Work preparation: Use copper tools to perform all maintenance and operation operations, and check that there is no hot work in the turbine room;

[0068] S2, system isolation: shut down the generator hydrogen dehumidification device, close the inlet and outlet, isolate and shut down the temperature detection unit;

[0069] S3, dehumidification device gas replacement: adjust the gas replacement unit, and perform gas replacement through the replacement inlet door and the replacement outlet door;

[0070] S4. Dehumidification device maintenance: maintenance personnel perform maintenance on the dehumidification device through the maintenance interface;

[0071] S5. System recovery and startup: After confirming that the maintenance and replacement are completed, open the valve of the hydrogen dehumidification device and start the hydrogen dehumidification device.

[0072] Optionally, the step S1 also includes closely monitoring the pressure inside the generator through the pressure detection unit during the replacement process, and strictly prohibiting carbon dioxide from entering the generator.

[0073] Optionally, the step S2 further includes closing all gas supply valves related to the hydrogen dehumidification device. In the step S2, it is also necessary to open the sewage discharge door at the outlet of the hydrogen dehumidification device to perform a dead corner discharge operation. In the step S2, the pressure formula for adjusting the hydrogen dehumidification device is:

[0074] P adj -P current +ΔP, where P adj is the adjusted pressure, P current is the current pressure, and ΔP is the pressure adjustment value determined according to the safety operation standard.

[0075] Optionally, the step S3 further includes adjusting the carbon dioxide bus pressure reducing valve to ensure that the pressure after the pressure reducing valve is about 0.6 MPa. The formula for calculating the carbon dioxide flow in the step S3 is:

[0076] in is the carbon dioxide flow rate, V inlet is the carbon dioxide inlet volume flow rate, A inlet is the carbon dioxide inlet cross-sectional area.

[0077] Optionally, the step S3 further comprises repeatedly performing the opening and closing operation of the valve at the replacement outlet ten times. In the step S3, the temperature formula for detecting and controlling the carbon dioxide is:

[0078] T outlet =T inlet +ΔT, where T outlet is the outlet temperature of carbon dioxide, T inlet is the carbon dioxide inlet temperature, and ΔT is the temperature increased by the heating device.

[0079] Optionally, step S5 also includes detecting whether the hydrogen pressure and purity in the generator are qualified by a pressure detection unit.

[0080] Optionally, in step S4, the formula for evaluating the purity of hydrogen is:

[0081] in, is the hydrogen purity percentage, is the actual measured hydrogen concentration, C min is the minimum acceptable hydrogen concentration, C max The highest hydrogen concentration.

[0082] Optionally, in step S5, the formula for calculating the regeneration time of the hydrogen dehumidification device is:

[0083] Among them, t regencrate is the regeneration time, V touer is the volume of the absorption tower of the dehumidification device, C regen is the carbon dioxide concentration required for regeneration, F regen is the carbon dioxide regeneration flow rate.

[0084] Optionally, in step S5, the dead angle removal time of the hydrogen dehumidification device is calculated as follows:

[0085] where t purge is the dead angle time, V dcad is the dead space volume of the dehumidification device, F purge is the hydrogen flow rate when exhausting dead corners.

[0086] This embodiment includes the following steps:

[0087] 1. Work preparation:

[0088] All maintenance and operation operations must be performed using copper tools;

[0089] Check and confirm that there is no hot work in the turbine room;

[0090] Add a temporary pipeline after the sewage discharge door at the outlet of the hydrogen dehumidification device for maintenance, and lead the pipeline outside the plant;

[0091] During the replacement process, the pressure inside the generator is closely monitored and it is strictly forbidden to allow carbon dioxide to enter the generator;

[0092] Contact the hydrogen station staff on duty in advance and be ready to refill hydrogen at any time.

[0093] 2. System isolation:

[0094] Shut down the generator hydrogen dehumidification device, switch the absorption tower of the hydrogen dehumidification device to the regeneration state and then shut down the power;

[0095] Close the generator hydrogen dehumidification device inlet valve;

[0096] Close the generator hydrogen dehumidification device outlet valve;

[0097] Isolate the generator hydrogen hygrometer and shut down the power;

[0098] Confirm that the bypass door of the motor hydrogen humidity meter is closed;

[0099] Close the secondary gas supply gate GL-21 from the #7 generator CO2 to the generator;

[0100] Close the manual secondary door GL-22 for the #7 generator CO2 to generator gas supply;

[0101] Close the manual primary door GL-43 of CO2 supply for generator #7;

[0102] 3. Gas replacement in dehumidification device #1 absorption tower:

[0103] Open the outlet valve of #1 or #2 carbon dioxide tank;

[0104] Put the primary carbon dioxide heating device into operation and open the inlet and outlet valves of the heating device;

[0105] Open the primary and secondary doors from CO2 to CO2 bus;

[0106] Open the valves before and after the CO2 bus pressure reducing valve;

[0107] Adjust the CO2 bus pressure reducing valve to ensure that the pressure after the pressure reducing valve is around 0.6MPa;

[0108] Put the carbon dioxide secondary heating device into operation and open the inlet and outlet valves of the heating device;

[0109] Open the hydrogen dehumidification device replacement inlet door GL-41;

[0110] Open the hydrogen dehumidification device replacement outlet door GL-42;

[0111] Close the cut-off valve AA003 of the hydrogen dehumidification device regeneration circuit;

[0112] Close the pressure equalizing valve AA004 of the hydrogen dehumidification device;

[0113] Switch the hydrogen dehumidification unit to the absorption tower for regeneration;

[0114] Close the hydrogen dehumidification device replacement outlet valve AA006;

[0115] Open the hydrogen dehumidification device to replace the inlet valve AA005;

[0116] Open the replacement inlet valve AA005 of the hydrogen dehumidification device. When the pressure in the hydrogen dehumidification device #1 tower reaches 0.2MPa, open the replacement outlet valve AA006 again to exhaust. After the exhaust is completed, close the replacement outlet valve AA006 of the hydrogen dehumidification device. Repeat this process ten times.

[0117] Open the hydrogen dehumidification device regeneration circuit switching valve AA003 and replace for 30 seconds;

[0118] After the replacement is completed, close the hydrogen dehumidification device and replace the inlet valve AA005;

[0119] Close the hydrogen dehumidification device replacement outlet valve AA006;

[0120] Check and confirm that the pressure in the dehumidification device absorption tower is 0;

[0121] Close all valves from the CO2 tank to the generator, and shut down the first and second level CO2 heating devices;

[0122] 4. Maintenance of dehumidification device absorption tower:

[0123] The dehumidification device absorption tower is overhauled by maintenance personnel;

[0124] If the absorption tower of the dehumidification device also needs to be overhauled, the absorption tower of the hydrogen dehumidification device should be switched to the regeneration state after the overhaul of the absorption tower is completed, and the gas in the absorption tower should be replaced according to step three, and then overhauled after the replacement is completed.

[0125] After the inspection is completed, perform the carbon dioxide replacement air operation in the dehumidification device absorption tower according to step three.

[0126] After the replacement is completed, close the CO2 tank outlet valve, the first-stage heater inlet and outlet valves, the CO2 to bus valve, the CO2 bus pressure regulating valve inlet and outlet valves, and the second-stage heater inlet and outlet valves, and shut down the first and second-stage heaters.

[0127] 5. Dead corners of hydrogen dehumidification device:

[0128] After confirming that the inspection and replacement are completed, open the bypass door of the inlet hydrogen hygrometer and the inlet door of the dehumidification device;

[0129] Open the sewage door behind the outlet door of the hydrogen dehumidification device, and the hydrogen dehumidification device will start to drain the dead corner;

[0130] It takes about 15 minutes to drain the dead corners. After the purity is qualified in the chemical test, the dead corners will be stopped.

[0131] If another absorption tower also needs to drain dead corners, the other absorption tower should be switched to the absorption state;

[0132] Close the sewage door behind the hydrogen dehumidification device outlet door, the bypass door of the inlet hydrogen humidity meter, and the dehumidification device inlet door;

[0133] 6. System recovery and startup;

[0134] Confirm that the cut-off valve AA003 of the regeneration circuit of the hydrogen dehumidification device is open;

[0135] The pressure equalizing valve AA004 of the hydrogen dehumidification device is opened two turns;

[0136] Open the inlet valve of the generator hydrogen dehumidification device;

[0137] Open the outlet valve of the generator hydrogen dehumidification device;

[0138] Open the secondary door GL-21 for the #7 generator CO2 to generator gas supply;

[0139] Open the manual secondary door GL-22 for supplying CO2 from #7 machine to the generator;

[0140] Open the manual primary door GL-43 of the CO2 supply of the #7 generator;

[0141] The hydrogen dehumidification device was powered on and put into operation, and the device was checked to be operating normally;

[0142] Check and confirm that the hydrogen pressure and purity in the generator are qualified;

[0143] This solution can realize the online isolation and maintenance of the hydrogen dehumidification device, avoid the unplanned shutdown of the unit, reduce the loss of frequent hydrogen discharge and replenishment, and enhance the safety and economic benefits of the unit operation.

[0144] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A generator hydrogen dehumidification device, characterized in that: include: a. an inlet for receiving hydrogen; b. an outlet for discharging the treated hydrogen; c. an internal structure for reducing the humidity of hydrogen gas as it flows through; d. An isolation system for isolating the unit for maintenance without stopping the machine; e. a control system for monitoring and controlling the flow of hydrogen and the operating status of the device; The control system comprises: i. a pressure monitoring unit for monitoring the pressure of the inlet and the outlet; ii. A temperature monitoring unit for monitoring the temperature of hydrogen; iii. A flow control unit, used to adjust the flow of hydrogen; iv. Safety interlock device to automatically cut off the hydrogen supply when an abnormal situation is detected; The isolation system comprises: i. One or more valves for controlling the inlet and outlet of hydrogen; ii. A gas replacement unit to safely replace hydrogen with other gases before maintenance; iii. A maintenance interface to allow maintenance personnel to safely enter the interior of the unit after isolation system operation.

2. A method for isolating a generator hydrogen dehumidification device, using the generator hydrogen dehumidification device according to claim 1, characterized in that: include: S1. Work preparation: Use copper tools to perform all maintenance and operation operations, and check that there is no hot work in the turbine room; S2, system isolation: turn off the generator hydrogen dehumidification device, close the inlet and outlet, isolate and turn off the temperature detection unit; S3, dehumidification device gas replacement: adjust the gas replacement unit, and perform gas replacement through the replacement inlet door and the replacement outlet door; S4. Dehumidification device maintenance: maintenance personnel perform maintenance on the dehumidification device through the maintenance interface; S5. System recovery and startup: After confirming that the maintenance and replacement are completed, open the valve of the hydrogen dehumidification device and start the hydrogen dehumidification device.

3. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: The step S1 also includes a replacement process in which the pressure in the generator is closely monitored by the pressure detection unit to prevent carbon dioxide from entering the generator.

4. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: The step S2 also includes closing all gas supply valves related to the hydrogen dehumidification device. In the step S2, it is also necessary to open the sewage discharge door at the outlet of the hydrogen dehumidification device to perform a dead corner discharge operation. In the step S2, the pressure formula for adjusting the hydrogen dehumidification device is: P adj -P current +ΔP, where P adj is the adjusted pressure, P current is the current pressure, and ΔP is the pressure adjustment value determined according to the safety operation standard.

5. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: The step S3 also includes adjusting the carbon dioxide bus pressure reducing valve to ensure that the pressure after the pressure reducing valve is about 0.6 MPa. The formula for calculating the carbon dioxide flow in the step S3 is: in is the carbon dioxide flow rate, V inlet is the carbon dioxide inlet volume flow rate, A inlet is the cross-sectional area of ​​the carbon dioxide inlet.

6. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: The step S3 also includes repeatedly performing the opening and closing operation of the valve at the replacement outlet ten times. In the step S3, the temperature formula for detecting and controlling the carbon dioxide is: T outlet =T inlet +ΔT, where T outlet is the outlet temperature of carbon dioxide, T inlet is the carbon dioxide inlet temperature, and ΔT is the temperature increased by the heating device.

7. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: The step S5 also includes detecting whether the hydrogen pressure and purity in the generator are qualified by a pressure detection unit.

8. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: In step S4, the formula for evaluating the purity of hydrogen is: in, is the hydrogen purity percentage, is the actual measured hydrogen concentration, C min is the minimum acceptable hydrogen concentration, C max The highest hydrogen concentration.

9. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: In step S5, the formula for calculating the regeneration time of the hydrogen dehumidification device is: Among them, t regencrate is the regeneration time, V touer is the volume of the absorption tower of the dehumidification device, C regen is the carbon dioxide concentration required for regeneration, F regen is the carbon dioxide regeneration flow rate.

10. The isolation method of a generator hydrogen dehumidification device according to claim 2, characterized in that: In step S5, the dead angle time of the hydrogen dehumidification device is calculated as follows: where t purge is the dead angle time, V dcad is the dead space volume of the dehumidification device, F purge is the hydrogen flow rate when exhausting dead corners.

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