DE102017107577A1 - power plant - Google Patents

Abstract

To an energy system (1, 30, 40), comprising at least one reactor (2) for the chemical reaction of educts into products, wherein the reaction energy, in particular in the form of electrical energy, supplies, and conveying means (9, 21) for conveying a the educt material stream containing the educts into the reactor (2) and / or product product stream containing the products from the reactor (2), wherein the conveying means (9, 21) are drivable by a propellant stream containing propellant, so as to improve energy , in particular electrical energy, provides with a higher efficiency, it is proposed that the propellant flow be different from the product flow.

Description

The present invention relates to an energy system, comprising at least one reactor for the chemical reaction of reactants to products, wherein the reaction energy, in particular in the form of electrical energy, supplies, and conveying means for conveying a reactant containing the educts in the reactor and / or one Products containing product stream from the reactor, wherein the conveying means are designed to be drivable by a propellant containing propellant stream.

A conventional energy system is for example from the US 2004/0150366 A1 known. The energy plant after the US 2004/0150366 A1 , which is referred to there as a power generation system 10, comprises a solid oxide fuel cell 16. The solid oxide fuel cell 16 is operated with a hydrocarbon fuel and air. The exhaust gas exiting the solid oxide fuel cell 16 passes through an air heat exchanger 26, transferring heat from the exhaust gas to the air to heat the air prior to entering the solid oxide fuel cell 16. The exhaust gas then passes through an oxidation system 14 (COPX) to heat the hydrocarbon fuel prior to entering the solid oxide fuel cell 16. Following this, the exhaust gas finally flows around the turbine 28 of a turbocharger 11, so that a compressor 12 of the turbocharger 28 is driven by the exhaust gas, thus compressing the air flowing into the power plant air.

However, the efficiency of such an energy system or of an analogously designed energy system with another fuel cell, such as a fuel cell with a proton-conducting membrane, noticeably smaller than the maximum achievable efficiency, the efficiency as a ratio between the energy supplied by them and her energy supplied for this purpose is defined.

The present invention is therefore an object of the invention to improve a generic power plant so that it provides energy, especially electrical energy, with a higher efficiency.

The object according to the invention is achieved with regard to the generic energy system in that the propellant stream is different from the product stream. With advantage for the efficiency of the energy system according to the invention can then be a propellant stream with a relation to the product material flow, for example, higher kinetic energy than, for example, prevails at a leakage of the product stream from the reactor, so that by the conveyor a corresponding differential energy from the propellant stream can be transferred to the reactant stream to increase its flow velocity. As a result, it is possible, in particular, to achieve optimal compression of the reactant stream in the case of a start-up operation of the energy system according to the invention by externally supplied energy of a gaseous stream of propellant, thereby improving the efficiency of the energy system according to the invention.

In the context of the invention, the propellant stream may be, for example, exhaust gas of an internal combustion engine, exhaust air of an air conditioning system, bleed air of a jet engine, ram air of an air intake system for an internal combustion engine or gas from a natural or synthetic gas source or mixtures thereof. For example, ambient air, which typically contains educts in the form of oxygen, comes into consideration as reactant stream.

Furthermore, the product stream is also suitable as Eduktstoffstrom into consideration, if it still contains starting materials and is fed to the reactor.

According to a particularly preferred embodiment of the energy installation according to the invention, it comprises conduit means for the recirculation of the product material stream into the reactor. Such recirculation is associated with a number of advantages. On the one hand, unused starting materials are returned to the reactor, so that the corresponding reaction yield and thus the efficiency of the energy installation according to the invention can be increased. Thereafter, surprisingly, the reactor can also be hermetically sealed off from the flow of propellant and thus from an environment surrounding it, so that the reactor can even be operated in an educt-free environment. In addition, in the case of gaseous educts, a higher gas flow in the reactor can be realized, so that the products from the reactor are advantageously discharged more reliably.

An energy system according to this embodiment of the invention thus comprises, for example, the reactor in the form of a fuel cell having a first inlet for oxygen and a second inlet for hydrogen and an oxygen source. The fuel cell has an input side and an output side and an anode side and a cathode side. On the input side, the educts (here oxygen and hydrogen) are supplied to the fuel cell, on the output side, the corresponding reaction product (water) is discharged. On the anode side, the oxidation of hydrogen takes place, on the cathode side, the reduction of oxygen, with protons on The cathode side by the reduction of oxygen to water connect (2H ⁺ + 2d ^- + ½ O ₂ → H ₂ O) by passing the protons through a membrane water is formed. The first inlet for oxygen is connected to the input side of the cathode side of the fuel cell, and the second inlet for hydrogen is connected to the input side of the anode side of the fuel cell. The energy system according to the invention then has a cathode-side connection, wherein the cathode-side connection is a connection between the output side of the cathode side of the fuel cell and the input side of the cathode side of the fuel cell. The oxygen source is connected to the cathode-side connection to compensate for the amount of oxygen reacted during the oxidation by means of an oxygen gas stream by the addition of oxygen. The energy system according to the invention further comprises an anode-side connection according to this embodiment, wherein the anode-side connection is a connection between the output side of the anode side of the fuel cell and the input side of the anode side of the fuel cell. The cathode-side connection thus serves for the recirculation of the oxygen not reacted in the fuel cell, the anode-side connection for the recirculation of the hydrogen not reacted in the fuel cell.

In a further advantageous embodiment of the energy installation according to the invention it is provided that it comprises supply means for supplying the product material stream with the educts on demand, the supply means being connected to the conduit means. Thereafter, for example, upon recirculation of the product stream into the reactor, the increasing depletion of the product stream of starting materials with increasing number of recycle cycles can be advantageously compensated.

The energy system according to the invention is further improved if the conveying means comprise at least one turbomachine with a driveline comprising a drive device, in particular a turbine, and an output device, in particular a compressor or a pump, wherein the drive device in the propellant flow and the output device in the educt flow and / or the product stream can be arranged. Advantageously, for the efficiency of the energy system according to the invention, the output device of the compensation of pressure losses in the reactor by kinetic energy of the propellant stream through the drive device to the output device and thus to the product material flow in the case of recirculation of the product stream in the reactor and / or on the Eduktstoffstrom is transmitted. In this case, the output device is particularly preferably arranged in the educt material stream and / or the product material stream such that condensation of the educt material stream and / or the product material stream in the output device is avoided. According to this embodiment, the turbomachine is configured, for example, as a turbocharger with a compressor and a turbine, wherein the turbine and the compressor are coupled together by a turbine shaft.

According to a further preferred embodiment of the energy system according to the invention, the turbomachine comprises at least one electric motor, wherein the electric motor is optionally coupled as a generator or motor to the drive train. It is already known from the prior art that an electric motor can drive a compressor for compressing a material flow, if the kinetic energy of a gas flow driving the compressor is insufficient for a required compression of the material flow. According to this embodiment, however, if necessary, excess energy of the fuel flow is fed by means of a generator operation of the electric motor in the form of electrical energy with advantage for the efficiency in the energy system according to the invention. The injected electrical energy is then provided, for example, for the operation of optional peripheral devices of the energy system according to the invention, which may be, for example, coolant pumps or recirculation pumps. Surprisingly, depending on whether the electric motor is coupled to the drive train of the turbomachine as a generator or motor, the educt material flow and, in the case of a recirculation of the product stream into the reactor, the product flow can be regulated. That is, as needed, excess kinetic energy of the propellant stream can be converted to electrical energy, while with a deficiency of kinetic energy, the turbomachine can be driven by the electric motor. However, the invention is not limited to such an electric motor. Rather, in the context of the invention, any machine into consideration, which can be driven by the turbomachine depending on their mode or can be driven by this to provide electrical energy.

When the energy system according to the invention has at least one moisture exchanger for exchanging moisture between the propellant stream and the product material stream and / or between the propellant stream and the educt material stream and / or at least one heat exchanger for exchanging heat between the propellant stream and the product material stream and / or between the propellant stream and Contains reactant stream, can advantageously the product stream or the educt material stream have an optimum temperature and humidity for the operation of the reactor and thus the energy system according to the invention.

The dewatering of the product stream is particularly important in a recirculation of the product stream into the reactor, as it can typically come to an increased moisture in the reactor during recirculation, so that corresponding power losses of the energy system according to the invention are surprisingly avoided by the moisture exchanger. This is particularly advantageous for a reactor designed as a polymer electrolyte membrane fuel cell, since in this case a critical moisture content in the reactor should prevail in order to ensure the stability of the polymer electrolyte membrane and thus the service life of the fuel cell.

In a preferred embodiment of the energy installation according to the invention, it comprises second conveying means for conveying a coolant stream containing a coolant and / or a heating medium stream containing a heating fuel into and / or out of the reactor, wherein the second conveying means are designed to be drivable by the propellant stream. This is particularly advantageous for a temperature control of the reactor, since the coolant circulation and / or the heating medium flow is circulated better by the second conveying means.

In an embodiment which is improved in contrast, it is provided that the energy system according to the invention comprises second conduit means for recirculating the fuel stream or the coolant stream into the reactor and / or a second heat exchanger for exchanging heat between the propellant stream and the heating medium stream or between the propellant stream and the coolant stream , As a result, it is possible, for example, to bring the reactor rapidly to its optimum operating temperature during start-up operation, so that in turn the efficiency of the energy system according to the invention is additionally improved.

The energy plant according to the invention is further improved if it comprises a condenser which can be arranged in the product stream for the purpose of dewatering the product stream and / or a separator which can be arranged in the product stream for purifying the product stream as required. Thereafter, the product stream is dewatered at an exit from the reactor and a flow through the capacitor with advantage for the efficiency of the energy system according to the invention. The separator may be, for example, a centrifugal separator for removing condensed water from the product stream, after which the efficiency of the energy system according to the invention is further improved.

Finally, it is advantageous if the reactor is designed as a fuel cell, in particular a fuel cell with a proton-conducting membrane. Thereafter, the chemical reaction of a fuel with oxygen can be used in the reactor to generate electrical energy. For this purpose, the fuel cell contains advantageously as a core component membrane-electrode units, which are each configured as a composite of an ion-conducting, in particular proton-conducting, membrane and in each case on both sides of the membrane arranged electrode (anode and cathode).

The invention will be described by way of example in a preferred embodiment with reference to a drawing, wherein further advantageous details are shown in the figures of the drawing.

• 1 zeigt eine prinzipmäßige Ansicht einer erfindungsgemäßen Energieanlage nach einer ersten Ausführungsform mit einer ersten Ventilschaltung;
• 2 zeigt eine prinzipmäßige Ansicht der erfindungsgemäßen Energieanlage nach 1 mit einer zweiten Ventilschaltung;
• 3 zeigt eine prinzipmäßige Ansicht einer erfindungsgemäßen Energieanlage nach einer zweiten Ausführungsform; und
• 4 zeigt eine prinzipmäßige Ansicht einer erfindungsgemäßen Energieanlage nach einer dritten Ausführungsform.

Functionally identical parts are provided with the same reference numerals.

• 1 shows a principle view of an energy system according to the invention according to a first embodiment with a first valve circuit;
• 2 shows a principle view of the energy system according to the invention 1 with a second valve circuit;
• 3 shows a principle view of an energy plant according to the invention according to a second embodiment; and
• 4 shows a principle view of an energy plant according to the invention according to a third embodiment.

1 shows a principle view of an energy plant according to the invention 1 according to a first embodiment with a first valve circuit. The energy plant 1 is to be used to generate electrical energy for operating a vehicle, aircraft, ship, submarine, family house, power plant or the like, not shown. The essential component of the energy system 1 is a fuel cell 2 , which is designed as a PEM fuel cell. This has a cathode 3 and an anode 4 on. The anode 4 is through an access line 109 Hydrogen supplied, the access line 109 is connected to a compressed gas storage, not shown here. At the anode 4 Unused hydrogen passes through recirculation lines 5 and a recirculation pump 6 back to an area of the anode entrance 4 and becomes the anode 4 if necessary mixed with fresh hydrogen supplied to the compressed gas storage, not shown here again. To the in the thus formed anode circuit for optimal operation of the anode 4 required hydrogen concentration are achieved by means of a schematically illustrated drain valve 7 and drainage pipes 8th Discharges the recirculated hydrogen drained. The fuel cell 2 further comprises a heat exchanger 29 to control their temperature.

The cathode 3 the fuel cell 2 ambient air is supplied as an oxygen supplier via a compressor 9 and an access line 10 fed. The compressor 9 compresses the ambient air, which it has on its input side via lines 11 and 12 is fed, wherein the lines 11 and 12 using a control valve shown here schematically 13 connected to each other by the control valve 13 in the embodiment of the power plant shown here 1 is switched accordingly. After the compressor 9 the ambient air flows into an enthalpy transformer 14 in which the humidity and temperature of such a cathode are supplied via a secondary medium flow from a turbine 21 is adapted by the Wasserdampfübertragung by the Enthalpieübertrager 14 is guaranteed. As a secondary medium flow can depending on the position of valves 13 and 22 the relatively damp cathode-side exhaust air and / or the ambient air from a branch line 26 be used. Thereafter, the ambient air flows to the cathode 3 the fuel cell 2 , Here, at least part of the oxygen contained in the ambient air in the fuel cell 2 reacted together with the anode-side hydrogen supplied. This creates electrical energy and water. Oxygen-depleted exhaust air carries the water from the fuel cell 2 with and then flows through an exhaust duct 15 in a condenser 16 in which the exhaust air is cooled to the extent that at least a portion of the water vapor contained in it condenses. Thereafter, the exhaust air flows through an exhaust duct 17 in a centrifugal separator 18 in which at least part of the condensed water is removed from the exhaust air. Thereafter, the exhaust air flows, which still one with respect to the ambient air in the line 11 increased pressure and a relative to the ambient air in the pipe 11 elevated temperature, through exhaust ducts 19 and 20 and then into a turbine 21 , where the exhaust ducts 19 and 20 using a control valve shown here schematically 22 connected to each other by the control valve 22 in the embodiment of the power plant shown here 1 is switched accordingly. In the area of the turbine 21 At least some of the kinetic energy present in the exhaust air is recovered and can drive the compressor 19 to provide. After the turbine 21 the relaxed exhaust air passes through an exhaust air line 23 into the environment, whereby the exhaust air before the Enthalpieübertrager 14 flows through. Alternatively or additionally, the ambient air due to a pressure difference between its cathode-side inlet and outlet in the fuel cell 2 on the side of the cathode 3 be fed, so on the compressor 9 and the turbine 21 can be waived.

The compressor 9 and the turbine 21 together form a turbocharger, which in the power plant according to the invention 1 according to the 1 also an electric motor 24 includes which additional drive power for driving the compressor 9 supplies, provided that in the area of the turbine 21 recovered kinetic energy of the exhaust air for the sole drive of the compressor 9 not enough. Provided the kinetic energy of the exhaust air in the area of the turbine 21 larger than that of the compressor 9 energy is needed, the electric motor 24 also be operated as a generator to electrical power, for example, for peripherals of the power plant 1 and / or facilities provided by them with electrical energy.

At this point it is expressly stated that in the energy system 1 to 1 Energy from the exhaust air, as is already known from the art, is recovered, since the control valves 13 and 22 are designed such that the exhaust air of the fuel cell 2 through the turbine 21 and the enthalpy transformer 14 flows. Thus are branch lines 25 and 26 which with the line 11 or the exhaust duct 19 connected by the corresponding circuit of the control valves 13 and 22 from the wires 11 and 19 shut off. Because the fuel cell 2 at the power plant 1 to 1 supplied with ambient air on the cathode side, it is not in addition to oxygen from an oxygen pressure gas storage schematically shown here 27 that has an oxygen line 28 to the line 10 connected, enriched.

2 shows a principle view of the energy system according to the invention 1 to 1 with a second valve circuit. At the power plant 1 here are the control valves 13 and 22 switched such that the lines 12 . 10 . 15 . 17 and 25 a closed to the environment recirculation circuit on the side of the cathode 3 the fuel cell 2 form. In the recirculation circuit is using the compressor 9 the exhaust air from the fuel cell 2 recirculated and if necessary via the oxygen line 28 with fresh oxygen from the oxygen pressure gas storage 27 provided. With the help of the enthalpy transformer 14 can excess thermal energy and / or humidity of the recirculated exhaust air, which accumulates with increasing number of recirculation cycles with heat and / or humidity, on through the lines 20 . 23 and 26 as well as the turbine 21 flowing exhaust gas from, for example, an air conditioning system not shown here are transmitted. Thereafter, depending on the desired operating conditions on an active cooling of the exhaust air through the condenser 16 be waived. The exhaust gas drives the turbine 21 and thus the compressor 9 at.

3 shows a principle view of an energy plant according to the invention 30 according to a second embodiment. The energy plant 30 is analogous to the energy system 1 from the 1 and 2 designed, with the control valves 13 and 22 according to 2 are switched so that the exhaust air is recirculated in a closed recirculation circuit. At the power plant 30 However, the exhaust gas flows out of the exhaust pipe 23 in a turbine 31 one. The turbine 31 transfers the corresponding kinetic energy of the exhaust gas to a pump 32 so the pump 32 is driven by the exhaust gas. The pump 32 Promotes a cooling and / or heating means through lines 33 . 34 and 35 , where the lines 33 and 35 directly to the heat exchanger 29 , which only for the sake of illustration against the 1 and 2 in the fuel cell 2 is arranged offset, is connected so that the cooling and / or heating means in a pass through the heat exchanger 29 Heat from the fuel cell 2 absorbs or heat to the fuel cell 2 emits. The cooling and / or heating medium flows depending on the circuit of a valve 37 on which the lines 34 and 37 as well as the pump 32 are connected, either from the line 34 through a plate heat exchanger 36 in which it depends on the operating conditions and the exhaust gas from the fuel cell 2 absorbed heat or one for heating the fuel cell 2 required heat from the exhaust gas, or from the heat exchanger 29 through the pipe 34 directly back to the pump 32 , The exhaust gas flows out of the turbine 31 in the heat exchanger 36 and then through a pipe 39 in the nearby areas.

The pump 32 and the turbine 31 together form a turbo pump, which in the energy plant according to the invention 30 according to the 3 also an electric motor 38 includes what additional drive power to drive the pump 32 supplies, provided that in the area of the turbine 31 recovered kinetic energy of the exhaust gas for the sole drive of the pump 32 not enough. Provided the kinetic energy of the exhaust gas in the area of the turbine 31 larger than that of the pump 32 energy is needed, the electric motor 38 also be operated as a generator to electrical power, for example, for peripherals of the power plant 30 and / or facilities provided by them with electrical energy.

4 shows a principle view of an energy plant according to the invention 40 according to a third embodiment. The energy plant 40 is analogous to the energy system 30 from the 3 designed, with the control valves 13 and 22 according to the 3 are switched so that the exhaust air recirculated in a closed recirculation, by the off-gas exhausted through the turbine 21 the compressor 9 drives. In contrast to the energy system 30 is the lead 39 the power plant 40 to a turbine 41 connected. The turbine 41 and therefore the exhaust drives the recirculation pump 6 to supply the anode 4 with hydrogen. After that, the exhaust gas flows through a pipe 42 in the nearby areas.

The turbine 41 and the recirculation pump 6 together form a second turbo pump, which in the energy system according to the invention 40 according to the 4 also an electric motor 43 includes which additional drive power for driving the recirculation pump 6 supplies, provided that in the area of the turbine 41 recovered kinetic energy of the exhaust gas for the sole drive of the recirculation pump 6 not enough. Provided the kinetic energy of the exhaust gas in the area of the turbine 41 greater than that of the recirculation pump 6 energy is needed, the electric motor 43 also be operated as a generator to electrical power, for example, for peripherals of the power plant 40 and / or facilities provided by them with electrical energy.

LIST OF REFERENCE NUMBERS

1

power plant

2

fuel cell

3

cathode

4

anode

5

recirculation

6

recirculation pump

7

drain valve

8th

drain line

9

compressor

10

access line

11

management

12

management

13

control valve

14

Enthalpieübertrager

15

exhaust duct

16

capacitor

17

exhaust duct

18

cyclone

19

exhaust duct

20

exhaust duct

21

turbine

22

control valve

23

exhaust duct

24

electric motor

25

branch line

26

branch line

27

Oxygen compressed gas storage

28

oxygen line

29

heat exchangers

30

power plant

31

turbine

32

pump

33

management

34

management

35

management

36

Plate heat exchanger

37

Valve

38

electric motor

39

management

40

power plant

41

turbine

42

management

43

electric motor

109

access line

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2004/0150366 A1 [0002]

Claims (11)

Energy plant (1, 30, 40), comprising at least one reactor (2) for the chemical reaction of reactants to produce, wherein the reaction energy, especially in the form of electrical energy, supplies, and conveying means (9, 21) for conveying a the educts containing educt material stream into the reactor (2) and / or a products containing the product product stream from the reactor (2), wherein the conveying means (9, 21) are designed drivable by a propellant-containing propellant stream, characterized in that the propellant stream from the product material stream is different. Energy system (1, 30, 40) after Claim 1 characterized in that it comprises conduit means (10, 12, 13, 15, 17, 25, 22) for recirculating the product stream into the reactor (2). Energy system (1, 30, 40) after Claim 2 characterized in that it comprises supply means (27, 28) for providing the product stream with the starting materials on demand, the supply means (27, 28) being connected to the conduit means (10, 12, 13, 15, 17, 25, 22) , Energy plant (1, 30, 40) according to any one of the preceding claims, characterized in that the conveying means (9, 21) at least one turbomachine (9, 21) with a drive device (21), in particular a turbine (21), and a Output device (9), in particular a compressor (9) or a pump comprising a comprehensive drive train, wherein the drive device (21) in the propellant stream and the output device (9) can be arranged in the Eduktstoffstrom and / or the product material stream. Energy system (1, 30, 40) according to one of the preceding claims, characterized in that the turbomachine (9, 21) comprises at least one electric motor (24), wherein the electric motor is optionally coupled to the drive train as a generator or motor. Energy plant (1, 30, 40) according to any one of the preceding claims, characterized in that it comprises at least one moisture exchanger (14) for exchanging moisture between the propellant stream and the product material stream and / or between the propellant stream and the educt material stream. Energy plant (1, 30, 40) according to one of the preceding claims, characterized in that it comprises at least one heat exchanger (14) for exchanging heat between the propellant stream and the product material stream and / or between the propellant stream and the educt material stream. Energy plant (1, 30, 40) according to any one of the preceding claims, characterized in that second conveying means (31, 32) for conveying a coolant stream containing a coolant and / or a fuel stream containing heating into the reactor (2) and / or from the Reactor (2), wherein the second conveying means (31, 32) are designed to be drivable by the propellant stream. Energy system (1, 30, 40) after Claim 1 characterized in that it comprises second conduit means (32, 33, 34, 35) for recirculating the fuel stream or stream into the reactor (2) and / or a second heat exchanger (36) for exchanging heat between the propellant stream and the heating stream or between the propellant stream and the coolant stream. Energy plant (1, 30, 40) according to any one of the preceding claims, characterized in that it comprises a condenser (16) which can be arranged in the product stream for dehydrating the product stream as required and / or a separator (18) which can be arranged in the product stream for purifying the product stream as required includes. Energy plant (1, 30, 40) according to one of the preceding claims, characterized in that the reactor (2) as a fuel cell (2), in particular a fuel cell (2) with a proton-conducting membrane, is configured.

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