RU2417487C1 - Power plant with electrochemical generator based on hydrogen-oxygen fuel elements and method of its operation - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: power plant with electrochemical generators (ECG) based on hydrogen-oxygen fuel elements (FE) includes a FE battery, systems of hydrogen and oxygen supply with pipelines to supply hydrogen and oxygen into the ECG FE battery, a sensor of the FE battery temperature, and also a control unit, it also comprises catalytic afterburners and temperature sensors, serially installed accordingly at pipelines of oxygen and hydrogen supply at the inlet to the ECG FE battery, the pipeline of hydrogen supply into the catalytic afterburner installed at the pipeline of oxygen supply into the FE battery with a throttle and a valve, connected with the pipeline of hydrogen supply into the FE battery and the pipeline of oxygen supply into the catalytic afterburner installed at the pipeline of hydrogen supply into the FE battery with a throttle and a valve, connected to the pipeline of oxygen supply into the FE battery.

EFFECT: higher reliability of connection and serviceability of electrochemical generator at low ambient temperatures.

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Description

The invention relates to power plants with electrochemical generators (ECG) based on hydrogen-oxygen fuel cells (TE) and can be used in the manufacture and operation of these power plants.

An analogue of the present invention can serve as a power plant (EU) with an electrochemical generator (ECG) based on hydrogen-oxygen fuel cells, described in (N.V. Korovin. "Electrochemical generators". M .: Energy. 1974, p. 93) . The specified EC with ECG contains a fuel cell battery (BFC) with a coolant circuit including a heat exchanger for heating the fuel cell battery. This is due to the fact that in all cases, in order for the fuel cells to work (and could work at a minimum load), a heater powered by an external energy source is required in order to ensure that the BFC is heated to operating temperature. Otherwise, the electrochemical processes in the BFC will be too slow, and the ECG will not be able to produce electricity. With a minimum allocated power, it can generally fail, since at low ambient temperatures it is practically impossible to remove reaction products (flooding of the fuel cell will occur). In this regard, the method of operation of similar EIs is that in cases where the temperature of the battery of fuel cells is (or falls) below the operating temperature, the battery is heated to operating temperature by a heater powered by an external energy source.

The closest in combination of essential features and the achieved technical result is a power plant with ECG based on oxygen-hydrogen fuel cells, which is a prototype. This EC with ECG based on hydrogen-oxygen fuel cells consists of a fuel cell battery, a hydrogen and oxygen supply system with pipelines for supplying hydrogen and oxygen to the electrochemical generator, an electrolyte circulation circuit with a pump and a heat exchanger for heating the fuel cell battery, and a temperature sensor for the fuel cell battery and a control unit for the operation of an electrochemical generator (RF Patent No. 2280924 of July 27, 2006, IPC: Н01М 8/04 (2006.01), Н01М 8/06 (2006.01)). The operation of the specified EA is as follows: during the start of the ECG from an extraneous energy source, turn on the pump of the coolant circuit, turn on the heater of the heat exchanger included in the coolant circuit. As a result of the operations, the BFC is heated to the minimum operating temperature, after which the valves for supplying hydrogen and oxygen to the ECG are turned on, as a result of which the ECG will begin to produce electricity in a predetermined amount, with the release of heat necessary for the evaporation of the formed water. During periods of minimum emitted ECG power and at low ambient temperatures, when the removal of reaction products (water) is difficult due to the lack of heat for evaporation, the heater of the heat exchanger entering the coolant circuit is switched on (from an external source of electricity), heating the BFC to the minimum operating temperature.

The disadvantages of this EC with ECG and the method of its operation are:

- long start-up time of the ECG;

- low reliability of switching on the ECG and its performance at low ambient temperatures;

- the inability to start the ECG in the absence of additional energy sources.

The objective of the invention is to increase the reliability of operation of EU.

The technical result is:

- improving the reliability of the inclusion and performance of ECG at low ambient temperatures;

- providing the ability to start ECG without additional extraneous energy sources through the use of a small part of the chemical energy of the working gases.

The specified technical result is achieved by the fact that in a power plant with an electrochemical generator based on hydrogen-oxygen fuel cells, including a battery of fuel cells, hydrogen and oxygen supply systems with pipelines for supplying hydrogen and oxygen to the fuel cell of an electrochemical generator, a temperature sensor of the fuel cell battery, as well as a control unit, introduced catalytic afterburners and temperature sensors, sequentially installed respectively on the pipeline oxygen and hydrogen supply at the inlet of the fuel cell of the electrochemical generator, a hydrogen supply pipe to the catalytic afterburner installed on the oxygen supply pipe to the fuel cell battery with a throttle and a valve connected to the hydrogen supply pipe to the fuel cell battery, and an oxygen supply pipe to the catalytic an afterburner installed on the pipeline for supplying hydrogen to the fuel cell battery with a throttle and a valve connected to the oxygen supply pipe and into the fuel cell battery.

The technical result is achieved by the fact that in the method of operating a power plant with an electrochemical generator based on hydrogen-oxygen fuel cells, which consists in heating the battery of fuel cells to operating temperature, the heating is carried out by heating the working components - hydrogen and oxygen supplied to the battery of fuel cells, this heating of the working components is carried out by feeding into each of these components an impurity of another component and catalytic combustion of the obtained thus hydrogen-oxygen mixtures.

With this method of operation, the technical result is also achieved by the fact that the mutual impurities of hydrogen and oxygen supplied to the battery of fuel cells are added in an amount not exceeding the lower ignition limit of the hydrogen-oxygen mixtures.

The invention consists in the following. The heat obtained by the interaction of gases - hydrogen and oxygen is supplied directly to the fuel cell, and the battery is heated not from the outside, but from the inside. In this case, the membranes and catalysts of the elements warm up first of all and rather quickly, since their thickness is small. Thanks to this, the TE battery can reach its nominal operating mode even before the entire ECG is warmed up.

Using the chemical energy of gases to produce heat at the start-up phase and during periods of minimum emitted ECG power and at low ambient temperatures, when the removal of reaction products is difficult due to lack of heat for evaporation, will make it possible to operate the ECG practically independent of external energy sources (except for switching on teams to start work). At the same time, the smallness of the mutual additions of oxygen and hydrogen ensures fire and explosion safety of the operation of EI with ECG.

The invention is illustrated in the drawing.

The drawing shows a schematic pneumohydraulic diagram of the claimed power plant with an electrochemical generator based on hydrogen-oxygen fuel cells.

The claimed power plant with an electrochemical generator based on hydrogen-oxygen fuel cells contains an electrochemical generator 1 with a battery of fuel cells 2, a hydrogen supply system 3, an oxygen supply system 4, a hydrogen supply pipe 5 to a fuel cell battery 2 of an electrochemical generator 1. The pipeline 5 is sequentially installed a catalytic afterburner 6 and a temperature sensor 7. On the pipeline 8 for supplying oxygen to the battery of fuel cells 2 of the electrochemical generator 1 is followed A catalytic afterburner 9 and a temperature sensor 10 are installed. An electrovalve 12 and a throttle 13 are installed on the pipe 11, which is designed to supply oxygen to the catalytic afterburner 13. An electric valve 15 and a throttle are installed on pipeline 14, which is designed to supply hydrogen to the catalytic afterburner 9. 16. The control unit 17 with a temperature sensor 18 are necessary to control the operation of the electrochemical generator 1.

Power plant with ECG 1 based on hydrogen-oxygen fuel cells 2 works as follows. At the initial moment, the control unit 17 is turned on and the readiness for operation of all elements of the power plant is checked, the temperature of the ECG is measured by the temperature sensor 18. During the start-up (start of work), regardless of the ambient temperature, the hydrogen supply system 3 and oxygen supply 4 are turned on, and through pipelines 5, 8, the working components — hydrogen and oxygen — enter the battery of fuel cells 2 of ECG 1. At the same time, valves 12, 15 are turned on, and components 11 through 14 pass through the chokes 13, 16 to the catalytic afterburners 6, 9. The afterburners 6 and 9 are made in the form of a reactor with a porous platinum-containing catalyst, on which a catalytic reaction of oxygen and hydrogen occurs with the formation of a hydrogen-oxygen mixture. In this case, the oxygen content entering the catalytic afterburner 6 does not exceed 3%, which is achieved using the throttle 13. This eliminates the possibility of ignition of gases in the hydrogen supply line. After the afterburner 6, hydrogen with a small content of water vapor enters the hydrogen cavity of the fuel elements and heats the membranes and catalysts of the elements from the hydrogen cavity. Since their thickness is small, the output to the operating mode of the ECG is significantly reduced (this can be judged by the current-voltage characteristic). The temperature of hydrogen at the entrance to the battery of fuel cells 2 ECG 1 is controlled by a sensor 7. For uniform heating of the fuel cell, heating is provided not only by the hydrogen cavity of the fuel cell, but also by oxygen. This is achieved in a similar way due to the catalytic afterburner 9. The content of hydrogen entering the afterburner 9 does not exceed 3%, which is achieved by the throttle 16. This eliminates the possibility of ignition of gases in the oxygen supply line. After the afterburner 9, oxygen with a small content of water vapor enters the oxygen cavity of the fuel cell and heats the membranes and catalysts of the elements from the side of the oxygen cavity. The oxygen temperature at the entrance to the ECG is controlled by the sensor 10. The temperature increase to the operating level (for example, up to ~ 90 ° C) is recorded by the temperature sensor 18. The signals from the temperature sensors 7, 10, 18 are fed to the ECG 17 control unit, which controls the operation of the valves 12 and 15. These valves overlap if:

- an emergency occurs and the temperature of the gases at the entrance to the ECG exceeds the maximum permissible value;

- during normal operation of the ECG, when the temperature of the battery of the fuel cell reaches its operating level.

These valves open if the temperature of the TE battery drops below its operating level.

Thus, the proposed invention solves the problem of improving reliability, eliminates a fire and explosion hazard situation and provides a quick exit of the power plant to operating mode.

Claims (1)

An energy installation with an electrochemical generator based on hydrogen-oxygen fuel cells, including a fuel cell battery, hydrogen and oxygen supply systems with pipelines for supplying hydrogen and oxygen to the fuel cell of the electrochemical generator, a temperature sensor of the fuel cell battery, and a control unit, characterized in that catalytic afterburners and temperature sensors are introduced into it, sequentially installed respectively on the oxygen and hydrogen pipelines at the entrance to the fuel cell battery of the electrochemical generator, a hydrogen supply pipe to the catalytic afterburner installed on the oxygen supply pipe to the fuel cell battery with a throttle and a valve connected to the hydrogen supply pipe to the fuel cell battery and an oxygen supply pipe to the catalytic afterburner installed on a pipeline for supplying hydrogen to a fuel cell battery with a throttle and a valve connected to a pipeline for supplying oxygen to a battery of fuel cells comrade