Saturated steam preparing and conveying device for simulating fuel cell tail emission test

Abstract

The utility model discloses a saturated steam producing and conveying device for simulating a fuel cell tail emission test, which comprises a producing container, an electric heater, a conveying pipeline and a heat tracing band, the producing container is connected with the electric heater, the output end of the producing container is connected with the conveying pipeline, and the heat tracing band is wrapped on the outer side of the conveying pipeline. The electric heater is arranged in the steam tank to produce high-temperature saturated steam, constant-temperature heat tracing treatment can be carried out on the conveying pipeline through the arrangement of the heat tracing belt, heat provided by heat tracing can make up for temperature drop and phase change latent heat loss caused by pressure reduction, and the condensation phenomenon is avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to hydrogen fuel cell test research technical field more particularly to a kind of saturated steam preparation and delivery device for simulating fuel cell tail exhaust testing. BACKGROUND

[0002] The tail gas after reaction of hydrogen fuel cell system mainly includes unreacted hydrogen, oxygen, water vapor;Among them, water vapor is generated due to the chemical reaction inside the fuel cell, that is, water generated by the reaction of hydrogen and oxygen;This part of water vapor exists in gaseous form in tail gas and the component proportion is relatively high, and a large amount of heat is released simultaneously with the reaction, so that the tail gas discharged from the tail exhaust port of fuel cell is in a high-temperature and high-humidity state.

[0003] According to the principle of thermodynamics, when the temperature of saturated gaseous water vapor decreases below the dew point temperature, condensation will begin. In a low-temperature environment, high-temperature steam will inevitably undergo phase change from gaseous to liquid due to the decrease in ambient temperature, and then a large amount of condensed water (white mist) will be produced in the tail exhaust. In order to prevent the accumulation of liquid water caused by the condensation of a large amount of high-temperature water vapor during the test of the fuel cell system, the liquid water will flow back to the laboratory tail exhaust pipeline and corrode the pipeline or freeze in a low-temperature environment. Therefore, during the test of the fuel cell, a steam condenser needs to be installed on the tail exhaust port of the fuel cell to condense and dehumidify the high-temperature saturated steam in the tail exhaust gas for pretreatment. The verification test of the tail exhaust steam condenser requires a stable high-temperature saturated steam source for supply and control delivery. SUMMARY

[0004] The technical problem to be solved by the utility model lies in how to improve the stability of saturated steam output.

[0005] The utility model solves the above technical problem by the following technical scheme: a saturated steam preparation and delivery device for simulating fuel cell tail exhaust testing, comprising a preparation container, an electric heater, a delivery pipeline and a heat tracing band. The preparation container is connected with the electric heater. The output end of the preparation container is connected with the delivery pipeline. The delivery pipeline is wrapped with the heat tracing band on the outside.

[0006] As a preferred technical scheme, a pressure reducing valve is arranged on the delivery pipeline.

[0007] As a preferred technical scheme, a flow controller is arranged on the delivery pipeline.

[0008] As a preferred technical scheme, the heat tracing band is wrapped with thermal insulation cotton on the outside.

[0009] As a preferred technical scheme, a first temperature sensor and a first pressure sensor are connected to the preparation container.

[0010] As a preferred technical scheme, the output end of the preparation container is connected with a venting unloading valve.

[0011] As a preferred technical scheme, the conveying pipeline is provided with a second pressure sensor, and the second pressure sensor is located downstream of the pressure reducing valve.

[0012] As a preferred technical scheme, the conveying pipeline is provided with a second temperature sensor and a third pressure sensor, the second temperature sensor is located downstream of the second pressure sensor, and the third pressure sensor is located upstream of the flow controller.

[0013] As a preferred technical scheme, the preparation container is connected with a water supplement pipeline and a water drainage pipeline, the water supplement pipeline is provided with a pure water supply valve, and the water drainage pipeline is provided with a water drainage hand valve.

[0014] As a preferred technical scheme, the preparation container comprises a steam tank, the steam tank is provided with a first liquid level sensor and a second liquid level sensor, and the plane where the second liquid level sensor is located is higher than the plane where the first liquid level sensor is located.

[0015] The beneficial effects of the utility model lie in:

[0016] (1) In the utility model, high-temperature saturated water vapor is prepared by arranging an electric heater in the steam tank, the conveying pipeline is subjected to constant temperature heat tracing treatment through the arrangement of the heat tracing band, and the heat provided by heat tracing can make up for the temperature drop and latent heat loss caused by pressure reduction, so that the condensation phenomenon is avoided.

[0017] (2) In the utility model, the emptying unloading valve arranged at the top end of the tank is used for safely discharging and protecting the steam pressure in the tank, and the use risk is avoided; the high-temperature steam is subjected to output constant pressure treatment by the pressure reducing valve and the heat tracing band respectively, so that the stability of the physical state of the high-temperature saturated water vapor is ensured, and the flow controller is additionally arranged on the conveying pipeline, so that the test working condition requirements under different flow rates during steam condensation test are met. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 The overall structure schematic view provided for the embodiment of the utility model;

[0019] Fig. 1 is a schematic view of the overall structure of the utility model, and Fig. 2 is a schematic view of the internal structure of the utility model. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0021] Referring to Figure 1 A saturated steam preparation and delivery device for simulating fuel cell tail exhaust test comprises a high-temperature saturated steam preparation unit, an adjusting unit and a delivery unit connected in sequence, the preparation unit comprises a preparation container, in the embodiment, a steam tank 5 is taken as an example, and of course, other forms of closed containers can also be used, the delivery unit comprises a delivery pipeline 17, and the adjusting unit comprises a pressure sensor, a temperature sensor, a valve and a flow controller 12 connected to the delivery pipeline 17, so as to adjust the temperature, flow and pressure of the output working medium, the steam tank 5 is connected with a water supply pipeline and a drainage pipeline, the water supply pipeline is provided with a pure water supply valve 1, the drainage pipeline is provided with a drainage hand valve 2, the steam tank 5 is provided with a first liquid level sensor 3 and a second liquid level sensor 4, the plane where the second liquid level sensor 4 is located is higher than the plane where the first liquid level sensor 3 is located, in the embodiment, the measured liquid levels of the first liquid level sensor 3 and the second liquid level sensor 4 are respectively taken as the set values of the low liquid level and the high liquid level;

[0022] In use, first, water is supplied through the pure water supply valve 1, and an appropriate amount of water is injected into the steam tank 5; the amount of the injected water is determined according to the volume of the heating tank and the design requirements, and considering the expansion space of the water after steam generation, the amount of the injected water generally cannot exceed the highest water level line, that is, the liquid level of the second liquid level sensor 4, so as to prevent the water from overflowing when boiling, and the specific water supply logic is as follows: when the liquid level line is at the liquid level of the first liquid level sensor 3, the pure water supply valve 1 is opened, and when the water supply liquid level reaches the liquid level of the second liquid level sensor 4, the water supply is stopped, and at this time, the pure water supply valve 1 is closed;

[0023] The steam tank 5 is connected with an electric heater 16, a conveying pipeline 17, a first temperature sensor 6, the conveying pipeline 17 is sequentially connected with a first pressure sensor 7, an emptying unloading valve 8, a pressure reducing valve 9, a second pressure sensor 10, a second temperature sensor 14, a flow controller 12, a third pressure sensor 13, and a heating band 11 is arranged outside the conveying pipeline 17, the heating band 11 is an electric heating band in the prior art, and heat preservation cotton 15 is arranged outside the heating band 11, the first temperature sensor 6 is used for measuring the steam temperature in the steam tank 5, and the first pressure sensor 7 is used for measuring the pressure in the steam tank 5; the emptying unloading valve 8 is used for emptying and unloading, preventing the steam pressure in the steam tank 5 from continuously rising abnormally or the gas pressure from fluctuating too much, so that the steam tank 5 is irreversibly damaged due to overpressure; the pressure reducing valve 9 is used for reducing the pressure of the steam at the outlet of the steam tank 5, that is, the inlet of the conveying pipeline 17, the second pressure sensor 10 is used for detecting the pressure value after the steam at the outlet of the steam tank 5 is reduced, the third pressure sensor 13 is used for monitoring the pressure value of the conveying pipeline 17, and the second temperature sensor 14 is used for detecting the temperature of the heating band 11; the second temperature sensor 14 is used as a temperature closed-loop control point of the heating band 11.

[0024] When the high-temperature steam is reduced in pressure, its state changes, according to the ideal gas state equation: PV = nRT, wherein P is pressure, V is the volume of the gas, n is the amount of substance, R is the gas constant, and T is the absolute temperature, when the pressure of the steam gas is reduced, if the volume is fixed in the pipeline container, the temperature of the steam will gradually decrease, until the saturation temperature point is reached and the condensation problem occurs, if the volume does not change and no other external heat is exchanged, in theory, the heat provided by the heating band 11 can make up for the temperature drop and the latent heat loss caused by the pressure reduction, so that the condensation phenomenon is avoided.

[0025] The high-temperature steam after pressure reduction flows to the input port of the gas flow controller 12 through the conveying pipeline 17, and the steam is output through the output port of the gas flow controller 12, the third pressure sensor 13 is used for monitoring the inlet test pressure of the high-temperature steam condenser when the gas flow controller 12 is in different output flow states, and the heat preservation cotton 15 wrapped outside the heating band 11 can reduce the heat loss of the gas in the process of conveying the high-temperature saturated steam to the greatest extent.

[0026] After the water replenishment is completed, the tester checks whether the electric heater 16 on the platform device is intact, whether the installation positions and calibration states of the first temperature sensor 6 and the first pressure sensor 7 are accurate, and whether the control valves of the water inlet and outlet and the steam outlet in the steam tank 5 are in the closed state; after the state inspection and water filling operation before all the preparation work is completed, the pure water vaporization heating is carried out by starting the electric heater 16, the first temperature sensor 6 will be taken as a closed loop control point of the target temperature of the steam in the tank, and the water temperature in the tank will gradually rise in the heating process, the water vapor generation rate rapidly rises, and the first pressure sensor 7 also gradually rises, until the actual temperature value reaches the test target setting value, the pressure in the tank will maintain a constant pressure saturation state.

[0027] When the liquid and the steam above it reach a dynamic equilibrium, that is, the vaporization speed of the liquid is equal to the condensation speed of the steam in the tank, the pressure of the steam at this time is called the saturated steam pressure, and it can be known from the saturated steam pressure data table of pure water that the water has a fixed saturated steam pressure value corresponding to different temperatures; for example, at 150 DEG C, the saturated steam pressure of water is about 476 kPa, if the steam pressure has not reached the saturated steam pressure, the water will continue to evaporate, so that the steam pressure rises, until the temperature is maintained at 150 DEG C, and the saturated steam pressure reaches a stable value, at this time, the water and the steam are in a dynamic equilibrium state, and the steam pressure in the container has reached a saturated state, in the embodiment, the first pressure sensor 7 is taken as an actual monitoring point of the saturated steam pressure value in the steam tank.

[0028] It should be noted that the fuel cell in the embodiment is a hydrogen fuel cell.

[0029] Method for use: the steam is prepared by arranging the electric heater 16 in the steam tank 5 to prepare high-temperature saturated water vapor; meanwhile, the pressure and temperature collection points arranged in the steam tank 5 are used to perform real-time closed loop control on the physical property parameters of the steam in the tank, the emptying and unloading valve 8 arranged at the top of the tank is used to perform safety pressure relief protection on the steam pressure in the tank, and the use risk is avoided; the pressure reducing valve 9 and the heat tracing band 11 are used to perform output constant pressure and constant temperature processing on the high-temperature steam respectively, so as to ensure the stability of the physical property state of the high-temperature saturated water vapor, and the flow controller 12 is additionally arranged on the conveying pipeline 17, so as to meet the test working condition requirements under different flow rates during the steam condensation test.

[0030] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A saturated steam production delivery device for simulating fuel cell tailpipe testing, characterized by, The device comprises a preparation container, an electric heater, a conveying pipeline and a heat tracing band, the preparation container is connected with the electric heater, the output end of the preparation container is connected with the conveying pipeline, and the conveying pipeline is wrapped with the heat tracing band.

2. A saturated steam generation and delivery apparatus for simulating fuel cell tailpipe emissions testing according to claim 1, wherein, A pressure reducing valve is arranged on the conveying pipeline.

3. A saturated steam generation and delivery apparatus for simulating fuel cell tailpipe emissions testing according to claim 1, wherein, A flow controller is arranged on the conveying pipeline.

4. The saturated steam generation and delivery device for simulating fuel cell tail exhaust testing of claim 1, wherein, The heat tracing band is wrapped with heat preservation cotton.

5. A saturated steam generation and delivery apparatus for simulating fuel cell tailpipe emissions testing according to claim 1, wherein, A first temperature sensor and a first pressure sensor are connected to the preparation container.

6. A saturated steam generation and delivery device for simulating fuel cell tailpipe emissions testing according to claim 1, wherein, An emptying unloading valve is connected to the output end of the preparation container.

7. A saturated steam generation and delivery apparatus for simulating fuel cell tailpipe emissions testing according to claim 2, wherein, A second pressure sensor is arranged on the conveying pipeline, and the second pressure sensor is located downstream of the pressure reducing valve.

8. A saturated steam generation and delivery apparatus for simulating fuel cell tailpipe emissions testing according to claim 7, wherein, A second temperature sensor and a third pressure sensor are arranged on the conveying pipeline, the second temperature sensor is located downstream of the second pressure sensor, and the third pressure sensor is located upstream of the flow controller.

9. A saturated steam generation and delivery apparatus for simulating fuel cell tailpipe emissions testing according to claim 1, wherein, A water supplement pipeline and a drainage pipeline are connected to the preparation container, a pure water supplement valve is arranged on the water supplement pipeline, and a drainage hand valve is arranged on the drainage pipeline.

10. The saturated steam generation and delivery device for simulating fuel cell tail exhaust testing of claim 1, wherein, The preparation container comprises a steam tank, a first liquid level sensor and a second liquid level sensor are arranged on the steam tank, and the plane where the second liquid level sensor is located is higher than the plane where the first liquid level sensor is located.

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