WO2020100486A1

WO2020100486A1 - Expansion turbine filling system for high-pressure hydrogen

Info

Publication number: WO2020100486A1
Application number: PCT/JP2019/040181
Authority: WO
Inventors: 吉田　純; 高橋　強
Original assignee: 株式会社日立プラントメカニクス
Priority date: 2018-11-14
Filing date: 2019-10-11
Publication date: 2020-05-22
Also published as: JP2020079628A

Abstract

In order to provide an expansion turbine filling system for high-pressure hydrogen, which has a simple configuration, has a low burden of maintenance management service, can reduce operation cost including power consumption cost, can use a general-purpose member as a constituent member of a hydrogen gas supply unit, and further can achieve smooth and efficient filling (reduction in fill time) and improvement in the energy use efficiency of a facility, this filling system reduces the enthalpy of hydrogen gas using an expansion turbine 11 when the hydrogen gas accumulated at a high pressure is pressurized and filled into a tank 6, and is provided with, at an outlet of the expansion turbine 11, a regenerator 14 containing a hydrogen-storing alloy, and a heat source for heating which heats the interior of the regenerator 14.

Description

High-pressure hydrogen expansion turbine filling system

The present invention provides hydrogen for filling hydrogen gas, which serves as fuel for a hydrogen automobile (hereinafter, simply referred to as “hydrogen automobile”) such as a fuel cell automobile, from a hydrogen gas supply source into a fuel tank of the hydrogen automobile. The present invention relates to a high pressure hydrogen expansion turbine type filling system applied to a temperature lowering system technology such as a precooler function in a final filling section of a filling facility (hereinafter, sometimes referred to as a “hydrogen station”).

Hydrogen gas used as fuel for hydrogen automobiles undergoes adiabatic expansion (isoenthalpy expansion) from high pressure in the expansion valve and other parts provided in the path filled with hydrogen gas Since it also expands in a high region, it has the property that the temperature after expansion rises due to the Joule-Thomson effect.
Therefore, at the hydrogen station, when the hydrogen gas, which is the fuel for the hydrogen vehicle, is filled from the hydrogen gas supply source into the fuel tank of the hydrogen vehicle, the hydrogen gas is filled at the portion such as the expansion valve provided in the path for filling the hydrogen gas. The temperature of the gas rises.

This increase in the temperature of the hydrogen gas becomes more remarkable as the expansion ratio of the hydrogen gas increases, so that the pressure of the supply gas from the hydrogen gas supply source at the hydrogen station is increased, for example, the pressure of the supply gas (the supply gas As the tank pressure increases from 45 to 70 MPa (G) and further to 82 MPa (G), the self-temperature rise amount further increases.
As an example, FIG. 1 shows an example of the self-temperature change at each secondary pressure when hydrogen gas is expanded in one step from 30 MPa at 70 MPa (G), which is the tank pressure of the supply source.

On the other hand, in the fuel cell vehicles that have started to be popularized at present, the maximum temperature upper limit during hydrogen filling is set to 85 ° C due to the temperature limitation due to the material of the fuel tank and the operating temperature of the fuel cell body cell.

Due to the above-mentioned properties of hydrogen, if hydrogen gas is directly filled without any means, the temperature at the time of hydrogen filling exceeds the maximum temperature upper limit of 85 ° C., and the temperature limit due to the material of the fuel tank and the fuel cell Since problems such as limitation of operating temperature of the main body cell and pressure drop due to cooling after filling occur, cooling means such as heat exchanger is arranged in the path for filling hydrogen gas, and this cooling means A method of filling a hydrogen automobile while cooling the hydrogen has been proposed and put into practical use (see, for example, Patent Document 1).

Here, FIG. 2 and FIG. 3 show configuration diagrams of the current general 70 MPa (G) hydrogen station.
This hydrogen station includes a compressor equipment 1 including a compressor unit that receives hydrogen gas, a hydrogen pressure storage equipment 2 including a pressure accumulator unit that stores the hydrogen gas sent from the compressor equipment 1, and a hydrogen pressure storage equipment 2. An expansion valve 3 and a hydrogen gas precooler 4 which are provided in a path for filling the hydrogen tank fuel tank 6 with the hydrogen gas, and a hydrogen precooling system 5 for cooling the hydrogen gas via the hydrogen gas precooler 4. Further, the hydrogen precooling system 5 is provided with a refrigerator facility 7 including a compressor, a condenser, an expansion valve, an evaporator, an accumulator, and the like, and a brine circuit 8 including a brine tank, a primary brine pump, a secondary pump, and the like. I am trying.
In both of the on-site type and off-site type hydrogen stations, the hydrogen received by the compressor facility 1 is an intermediate pressure (40 MPa (G) in the figure) or a high pressure (82 MPa (G in the figure). )) And is held in the form of compressed gas in the pressure accumulator unit of the hydrogen accumulator 2 at the respective pressures.
In order to fill the in-vehicle fuel tank 6 on the demand side with these hydrogen gases, expansion is performed via the expansion valve 3, but at that time, the temperature of the hydrogen gas itself rises, so that it is necessary to use external equipment. It is cooled to -40 ° C by a certain hydrogen precooling system 5.
According to the current technology, the hydrogen precooling system 5 is configured by combining a normal refrigerator facility 7 such as a CFC refrigerant and a brine circuit 8 operating at around −40 ° C., so that the configuration is complicated, Moreover, many rotary devices such as a refrigerant compressor for a refrigerator, a primary brine pump, and a secondary brine pump are also required.

Therefore, the conventional hydrogen precooling system used to lower the temperature of the hydrogen gas in the final filling part of the hydrogen station has the following problems.
1) Externally independent hydrogen precool system is a system that operates by external power. It is about 40 kW at a general hydrogen station (300 Nm ³ / h), and the operation of the hydrogen precooling system itself raises the operating cost.
2) Because CFCs (alternative CFCs) are used as refrigerants in refrigerators, they are legally treated, and this precooler facility itself is subject to the refrigeration and safety regulations of the High Pressure Gas Safety Law, which limits its facilities and operations.
3) Having CFCs and brine in the station requires measures to prevent environmental accidents due to external leakage of CFCs and brine.
4) Since the hydrogen precooling system is complicated by the two-stage configuration of the refrigeration circuit and the brine circuit, and there are a plurality of rotating machines such as the refrigerant compressor and the brine pump, many maintenance management services occur.
5) Since it is a system that uses brine, it takes time from the start of operation to the steady state. Therefore, it is necessary to start the hydrogen precooling system in advance and keep the system in a steady state long before the filling work.
6) When downsizing the installation space of the hydrogen station itself, the exclusive space of the hydrogen precooling system is a limitation.
7) At the current temperature of -40 ° C, there will be restrictions on the rapid filling of hydrogen. In the future, in order to further shorten the filling time, pre-cooling to a temperature lower than the current -40 ° C may be required.

By the way, in view of the problems of the hydrogen precooling system used for lowering the temperature of the hydrogen gas in the final filling part of the above-mentioned conventional hydrogen station, the applicant of the present invention has previously proposed that the configuration is simple and the maintenance management service is performed. We proposed a hydrogen precooling system used for lowering the temperature of hydrogen gas at the final filling part of a hydrogen station, which has a low burden and can reduce operating costs including power consumption (see Patent Document 2).

The hydrogen pre-cooling system used to lower the temperature of hydrogen gas at the final filling part of this hydrogen station uses the expander (expansion turbine) to lower the temperature of hydrogen gas during the process of expanding and decompressing hydrogen gas, and the cold energy Is used for precooling hydrogen gas, and it is possible to solve the problems of the hydrogen precooling system used for lowering the temperature of hydrogen gas in the final filling section of the conventional hydrogen station. there were.

More specifically, in this hydrogen precooling system, as shown in FIG. 4, the hydrogen gas source line 9 is connected to the circuit of the expansion turbine 11, and the expansion turbine 11 finally expands the hydrogen gas, The high pressure hydrogen expansion turbine type filling system 10 is configured to fill the enthalpy lowered (temperature lowered) hydrogen gas into the fuel tank 6 of the hydrogen vehicle via the hydrogen gas supply unit 13.
Although the example shown in FIG. 4 uses the turbine / compressor in which the turbine 11a and the compressor 11b are coaxially arranged in the expansion turbine 11, the expansion turbine 11 may be configured by only the expansion turbine.

Here, FIG. 5 shows changes in filling flow rate, pressure, and temperature by expansion (valve expansion) using a hydrogen gas expansion valve (conventional method) and expansion turbine type charging system for high-pressure hydrogen (new method).

By the way, in the high pressure hydrogen expansion turbine type filling system 10, the temperature of the outlet of the expansion turbine 11 is not constant because it is determined by the expansion ratio of the expansion turbine 11 which changes every moment.
That is, as shown in a typical calculation example of the turbine outlet (= filling tank inlet) temperature in FIG. 5, “Tin [new method]” is the outlet temperature of the expansion turbine 11 in the expansion turbine type filling system 10 for high pressure hydrogen. (= Example of behavior of filling tank inlet temperature).) In the initial stage of filling, the expansion ratio of the expansion turbine 11 is high, so that the temperature of hydrogen gas drops to near −70 ° C. for a short time. Areas arise.
As described above, since there is a time period when the temperature of the hydrogen gas falls below -40 ° C, it is necessary to make the constituent members of the hydrogen gas supply unit 13, for example, the sealing material of the filling hose compatible with -70 ° C. However, there was a problem that this would lead to an increase in equipment costs (Problem 8).

JP 2004-116619 A JP, 2017-150660, A

In view of the problems of the hydrogen precooling system used for lowering the temperature of hydrogen gas in the final filling section of the above-mentioned conventional hydrogen station, the present invention has a simple configuration, a low burden of maintenance and management services, and power consumption. The operating cost including the cost can be reduced, general-purpose members can be used as the constituent members of the hydrogen gas supply unit, and smooth and efficient filling (shortening of filling time) and energy utilization efficiency of equipment can be achieved. It is an object of the present invention to provide an expansion turbine type filling system for high-pressure hydrogen capable of improving the fuel consumption.

In order to achieve the above object, the high pressure hydrogen expansion turbine type filling system of the present invention is a filling system for performing enthalpy lowering of hydrogen gas using an expansion turbine when pressurizing and filling hydrogen gas accumulated at high pressure into a tank. The system is characterized in that a regenerator having a hydrogen storage alloy incorporated therein is provided at the outlet of the expansion turbine, and a heating heat source for heating the inside of the regenerator.

In this case, a turbine compressor can be used for the expansion turbine.

Further, at the time of releasing the hydrogen gas of the hydrogen storage alloy, the high temperature fluid extracted from the exhaust heat side to the aftercooler of the turbine / compressor is guided to the regenerator containing the hydrogen storage alloy and returned to the aftercooler after heat exchange. A circuit can be provided.

In addition, when releasing the hydrogen gas of the hydrogen storage alloy, a high-temperature fluid extracted from the exhaust heat side of the hydrogen filling equipment is guided to a regenerator containing the hydrogen storage alloy, and a circuit for returning to the exhaust heat side after heat exchange is provided. be able to.
Here, the exhaust heat side of the hydrogen filling equipment refers to equipment that releases the exhaust heat in the hydrogen filling equipment, specifically, each cooler of a hydrogen compressor, a cooler of a precool chiller equipment, and the like.

According to the high-pressure hydrogen expansion turbine type filling system of the present invention, when the hydrogen gas accumulated at a high pressure is charged under pressure into the tank, the expansion turbine finally expands the hydrogen to lower the enthalpy (temperature drop). ) By filling the regulated tank side with hydrogen gas, the configuration is simple, the burden of maintenance and management services is low, and the operating costs including power consumption costs can be reduced. It is possible to provide a hydrogen precooling system used to reduce the temperature of hydrogen gas in the filling section.
Then, by providing a regenerator having a hydrogen storage alloy built in at the outlet of the expansion turbine, the degree of temperature drop of hydrogen gas at the initial stage of filling when the expansion ratio of the expansion turbine is high is relaxed and smoothed, and the hydrogen gas supply unit It is possible to use general-purpose members as the component members of the above, and it is possible to prevent the equipment cost from rising, and smooth and efficient filling (shortening of filling time) and improvement of energy utilization efficiency of equipment. Can be planned.

Further, by using a turbine compressor for the expansion turbine, that is, by using a turbine compressor having an expansion impeller on one side of a rotary shaft and a compression impeller on the other side, the energy generated in the expander is extracted. In addition, it is not necessary to provide a separate means for effective use, and the rotational energy obtained on the turbine side is used to increase the pressure of hydrogen gas on the compressor side so that the hydrogen gas is guided to the turbine inlet. The expansion ratio of the turbine increases as much as the pressure is increased by the compressor, so that a larger heat drop (= amount of cold generation) can be obtained.

6 is a graph showing changes in filling flow rate, pressure, and temperature due to expansion (valve expansion) of hydrogen gas using an expansion valve. It is explanatory drawing of the hydrogen station using the conventional hydrogen precooling system. It is explanatory drawing of the hydrogen station using the conventional hydrogen precooling system. It is explanatory drawing which shows an example of the expansion turbine type filling system of the high pressure hydrogen of a new system. It is a graph which shows the change of the filling flow rate and pressure of the expansion (valve expansion) (conventional system) which used the expansion valve of hydrogen gas, and the expansion turbine type | system | group filling system (new system) of high-pressure hydrogen, and the change of temperature. It is explanatory drawing which shows one Example of the expansion turbine type filling system of the high pressure hydrogen of this invention. It is explanatory drawing which shows one Example of the expansion turbine type filling system of the high pressure hydrogen of this invention. It is explanatory drawing which shows one Example of the expansion turbine type filling system of the high pressure hydrogen of this invention. It is explanatory drawing which shows one Example of the expansion turbine type filling system of the high pressure hydrogen of this invention.

An embodiment of a high-pressure hydrogen expansion turbine type filling system of the present invention will be described below with reference to the drawings.

As shown in FIG. 6, this high-pressure hydrogen expansion turbine-type filling system uses the high-pressure hydrogen expansion turbine-type filling system of the present invention for reducing the temperature of hydrogen gas at the final filling portion of a hydrogen station. An outlet of the expansion turbine 11 in a filling system that is applied to a pre-cooling system, in which the enthalpy of the hydrogen gas is lowered by using the expansion turbine 11 when the tank 6 is pressurized and filled with hydrogen gas accumulated at a high pressure. In addition, a regenerator 14 containing a hydrogen storage alloy therein and a heating heat source (not shown) for heating the inside of the regenerator 14 are provided.

Here, the expansion turbine 11 may be configured by only an expansion turbine, but in the present embodiment, it is a turbine / compressor, that is, a rotary shaft that is generally used to perform compression and expansion of a refrigerant in the past. A turbine compressor having an expansion impeller on one side and a compression impeller on the other side is used.

Specifically, like the final expansion mechanism of hydrogen gas at the hydrogen station shown in FIG. 6, this high pressure hydrogen expansion turbine type filling system 10 connects the hydrogen gas source line 9 to the circuit of the expansion turbine 11. The hydrogen gas is finally expanded in the expansion turbine 11 and the enthalpy lowered (temperature lowered) hydrogen gas is filled into the fuel tank 6 of the hydrogen vehicle via the hydrogen gas supply unit 13. I have to.

Here, the expansion turbine 11 is provided with a turbine 11a having an expansion impeller on one side of a rotating shaft and a compressor 11b having a compression impeller on the other side, and uses the rotational energy obtained on the turbine 11a side. Then, the pressure of the hydrogen gas is increased on the compressor 11b side so as to be guided to the inlet of the turbine 11a (the hydrogen gas is supplied to the compressor 11b and then to the turbine 11a). The expansion ratio of the turbine 11a is increased by the amount of pressure increased by the compressor 11b, and a larger heat drop (= cold generation amount) can be obtained.

Further, the cooler 12 can be provided at the inlet of the expansion turbine 11 on the turbine 11a side.
As the cold heat source 12a of the cooler 12, a water cooling type or a chiller unit type can be preferably used.
Thereby, the temperature drop of hydrogen gas can be assisted.

Fig. 5 shows changes in the filling flow rate and pressure and temperature due to expansion using a hydrogen gas expansion valve (valve expansion) (conventional method) and high-pressure hydrogen expansion turbine type charging system (new method).

By applying the high pressure hydrogen expansion turbine filling system 10 to the hydrogen precooling system used to lower the temperature of the hydrogen gas at the final filling part of the hydrogen station, the high pressure (82 MPa) of the hydrogen gas source line 9 (original) It is possible to drive the expansion turbine 11 using the pressure difference from the hydrogen gas of (pressure) to the fuel tank 6 of the hydrogen automobile to directly fill the expanded hydrogen gas.
In this case, since the difference between the original pressure and the internal pressure of the fuel tank 6 is large at the initial stage of filling, the expansion ratio of the turbine 11a and the expansion ratio of the compressor 11b can be made relatively large, so that more cold is generated. You can
As the filling progresses, the internal pressure of the fuel tank 6 rises and the cold generated by the expansion turbine 11 becomes smaller, but the filling can be finally finished at 85 ° C. or lower.

By the way, the expansion turbine type filling system 10 for high-pressure hydrogen, if nothing is done, takes a short time because the expansion ratio of the expansion turbine 11 is high in the initial stage of filling as shown in FIG. A region where the temperature of hydrogen gas drops to near -70 ° C occurs.

Therefore, in the high pressure hydrogen expansion turbine type filling system 10 of the present embodiment, a regenerator 14 having a hydrogen storage alloy built therein is provided at the outlet of the expansion turbine 11.
Here, the hydrogen storage alloy includes AB2 type (based on alloys of transition elements such as titanium, manganese, zirconium, and nickel) and AB5 type (rare earth elements, niobium, zirconium 1 having a catalytic effect on transition). Based on alloys containing elements (nickel, cobalt, aluminum, etc.) 5 (LaNi ₅ , ReNi _5, etc.), Ti (titanium) -Fe (iron) -based, V (vanadium) -based, Mg (magnesium) Any conventionally used hydrogen storage alloy such as an alloy system, a Pd (palladium) system, or an alloy system of Ca (calcium) and a transition element (such as nickel) can be appropriately used.
Further, it is preferable that the regenerator 14 be detachably incorporated into a pipe connected to the outlet of the expansion turbine 11 via a connection joint.

The regenerator 14 containing the hydrogen storage alloy relaxes and smoothes the temperature drop of the hydrogen gas in the initial stage of filling when the expansion ratio of the expansion turbine 11 is high, and specifically, −40 ° C. to −45. In order to operate at a temperature of 0 ° C., it is possible to use a general-purpose member as a component of the hydrogen gas supply unit 13, for example, a sealing material for a filling hose, which is not compatible with −70 ° C. In particular, a regenerator that can handle low temperatures can be used.

Here, the regenerator 14 has a tank structure formed of a pressure resistant container, and the pressure resistant container is provided with a heat insulating structure so that heat input / heat radiation from the outside can be suppressed or controlled. It has a built-in hydrogen storage alloy.
The regenerator 14 has a single tank structure consisting of a hydrogen storage alloy built-in so that the entire amount of hydrogen gas can be led to the hydrogen storage alloy. It is also possible to have a configuration in which a plurality of tanks each containing a regenerator other than the storage alloy are arranged side by side so that a part of the hydrogen gas can be guided to the hydrogen storage alloy.
The regenerator is not particularly limited, but is a metal using a metal having a honeycomb structure such as copper or stainless steel, a honeycomb regenerator, or a metal using a ribbon-shaped metal such as copper or stainless steel. (Ribbon scourer) Filling type regenerator, beads or gel of isopropyl alcohol (low temperature regenerator consisting of beads and gel that puts in and out heat in the form of solidification heat at a predetermined target temperature. For example, "PlusICE" ( An alcohol bead (gel) built-in regenerator using a product name (Phase Change Material Products Limited) can be preferably used.

In the regenerator 14 containing the hydrogen storage alloy, the hydrogen gas is taken into the hydrogen storage alloy when the hydrogen gas is at a low temperature, and the hydrogen gas is released from the hydrogen storage alloy when the hydrogen gas is at a high temperature.
In this high-pressure hydrogen expansion turbine filling system, the turbine outlet temperature is low (-40 ° C or lower) in the initial (first half) of the expansion + filling operation, so the hydrogen storage alloy built in the regenerator 14 is hydrogen gas. To occlude.
On the other hand, in the latter half of the expansion + filling operation, the turbine outlet temperature is close to room temperature, so the hydrogen storage alloy contained in the regenerator 14 operates to release the stored hydrogen gas.
This operation is actually an operation of putting in and out the hydrogen gas corresponding to the pressure and temperature conditions before and after the equilibrium point of the hydrogen storage alloy.
As a result, when the temperature is low, the effect of suppressing the temperature and flow rate (supply amount) of hydrogen gas of -40 ° C or lower (further cold storage effect) is exerted, and when the temperature is near room temperature, the flow rate (supply amount) of hydrogen gas is reduced. Exerts the effect of increasing.
As a result, smooth and efficient filling (shortening of filling time) can be realized in terms of the cold storage effect and flow rate distribution from both the temperature and flow rate (supply amount) of hydrogen gas.

Thus, by providing the regenerator 14 at the outlet of the expansion turbine 11 in this way, at the initial stage of filling when the expansion ratio of the expansion turbine 11 is high, the temperature at the outlet of the expansion turbine 11 reaches close to −70 ° C. The cold hydrogen is absorbed by passing the cold hydrogen gas through a regenerator 14 containing a hydrogen storage alloy, and the cold gas is supplied at about -40 ° C. The cold energy stored in the regenerator 14 containing the hydrogen storage alloy releases the cold energy in the latter half of the filling process, that is, as the temperature of the outlet of the expansion turbine 11 rises, and the whole temperature behavior is changed. It can be smoothed.

By the way, the heating heat source for heating the inside of the regenerator 14 is for moving the equilibrium state point of hydrogen storage by the hydrogen storage alloy to a state in which hydrogen is easily released, and the regenerator 14 has a heating heat source such as a heater ( An internal heating heat source (not shown) may be incorporated, or the exhaust heat side of the hydrogen filling equipment may be used as the heating heat source (external heating heat source) 15, as shown in FIGS.

Here, when the exhaust heat side of the hydrogen filling equipment is used as the heating heat source (external heating heat source) 15, as shown in FIGS. 7 to 9, when the hydrogen gas of the hydrogen storage alloy is released, the hydrogen filling equipment is exhausted. A circuit is provided in which the high-temperature fluid extracted from the heat side is guided to the regenerator 14 containing a hydrogen storage alloy and returned to the heat exhaust side after heat exchange.
Here, the exhaust heat side of the hydrogen filling equipment refers to equipment that releases the exhaust heat in the hydrogen filling equipment, specifically, each cooler of a hydrogen compressor, a cooler of a precool chiller equipment, and the like.
As a result, the external heat source can be used, and the energy efficiency corresponding to the exhaust heat utilization of the entire hydrogen station can be improved.

Then, as shown in FIGS. 7A and 8A, in addition to using the exhaust heat side of the hydrogen filling equipment as a heating heat source (external heating heat source) 15, FIGS. As shown in b), the exhaust heat to the aftercooler of the turbine / compressor (the cooler 12 provided at the inlet of the expansion turbine 11 on the turbine 11a side) is partially used to further save energy in the entire system. The effect is obtained.
Specifically, as shown in FIGS. 7B and 8B, when the hydrogen gas of the hydrogen storage alloy is released, the aftercooler of the turbine / compressor (the inlet portion of the expansion turbine 11 on the turbine 11a side). It is possible to provide a circuit in which a required amount of high-temperature fluid extracted from the side of heat exhausted to the cooler 12) provided in the above is introduced into the regenerator 14 containing a hydrogen storage alloy and returned to the aftercooler outlet side after heat exchange.

Here, the heating heat source is an internal heating heat source, an external heating heat source, an aftercooler of the turbine / compressor (the inlet portion of the expansion turbine 11 on the turbine 11a side, depending on the actual operating conditions of the expansion turbine type filling system for high-pressure hydrogen). The exhaust heat to the cooler 12) provided in the can be appropriately selected.

By the way, in the present system in which the expansion turbine performs the hydrogen filling operation, the hydrogen filling amount (flow rate) decreases in the latter half of the filling (when the system pressure is relatively high). In the latter half of this filling, the hydrogen gas already stored in the hydrogen storage alloy is released and contributes to the filling, so that a more rational operation of the filling system becomes possible.
The effect demanded of the regenerator 14 having the hydrogen storage alloy built therein is mainly intended to release the hydrogen once stored in the hydrogen storage alloy in a high pressure state and to release the hydrogen again for the purpose of superiority in the process.
In this case, in order to release the hydrogen stored in the hydrogen storage alloy to the process side, it is necessary to shift the equilibrium state point of hydrogen storage to a state in which hydrogen is released more easily. , You need to raise the temperature. However, since the pressure in the system is relatively high in the latter half of the filling, it is necessary to heat the storage alloy with the internal heating heat source or the external heating heat source in order to effectively release the storage alloy while keeping the same temperature. By appropriately providing this heat amount, the filling amount (flow rate) of hydrogen at the pressure and temperature can be increased by the amount of hydrogen released from the hydrogen storage alloy, and the filling rate can be increased.

As shown in FIGS. 7 (a) and 7 (b), the regenerator 14 is constructed by incorporating a hydrogen storage alloy therein, and as shown in FIGS. 8 (a) and 8 (b), , A conventional regenerator 16 incorporating the other regenerator described above is combined, and most of the regenerator 16 functions as a normal regenerator 16. When hydrogen is excessive or insufficient, a regenerator containing a hydrogen storage alloy is incorporated. The vessel 14 may be used to optimize the hydrogen supply balance.
Further, as shown in FIG. 9, it is possible to cope with a wider range of operating conditions by using a circuit configuration in which two regenerators 14 each containing a hydrogen storage alloy are combined. In this case, for example, it is possible to release hydrogen (pressurize operation) in one of the regenerators 14 while operating to store hydrogen in one of the regenerators 14, and to determine the optimum hydrogen filling amount (flow rate) in the filling process. It is possible to supply.

By applying the high-pressure hydrogen expansion turbine type filling system of the present invention to a hydrogen precooling system used for lowering the temperature of hydrogen gas in the final filling part of a hydrogen station, hydrogen is added to the final filling part of a conventional hydrogen station. The problems of the hydrogen precooling system used to lower the temperature of the gas can be solved as follows.
Regarding the problem 1), since the external power is not required to operate the expansion turbine itself, almost no power is required with respect to the operating cost (electricity cost) of the conventional hydrogen precooling system.
Regarding the problem 2), since there is no refrigerant, the system does not follow the refrigeration law separately. It can be dealt with in the high pressure gas safety law of the entire hydrogen station.
Regarding problem 3), there is no risk of environmental accidents because there is no CFC refrigerant or brine itself.
Regarding issue 4), since the system configuration is fairly simple, not only operating costs but also maintenance costs can be significantly reduced.
Regarding the problem 5), since a temperature drop state can be created at the same time when the expansion turbine is started, the time constant in the system is very small. Pre-launch time will be short.
With regard to Problem 6), only the cold box of the expansion turbine is required, so that a large space saving can be achieved. The volume ratio is about 10% compared to the conventional one.
Regarding issue 7), it is possible to easily increase the equipment flow rate by combining a plurality of expansion turbines or using an expansion turbine with an optimum flow rate, and without using a large precooling cooler, a large fuel cell bus or truck. It is possible to configure the filling equipment of.
Regarding the problem 8), by providing a regenerator having a hydrogen storage alloy built in at the outlet of the expansion turbine, the degree of temperature drop of hydrogen gas at the initial stage of filling when the expansion ratio of the expansion turbine is high is relaxed and smoothed, It is possible to use general-purpose members as the constituent members of the hydrogen gas supply unit, and it is possible to prevent an increase in equipment costs. Furthermore, smooth and efficient filling (shortening of filling time) and equipment It is possible to improve the use efficiency of the energy.
Further, by using a turbine compressor for the expansion turbine, it is not necessary to separately provide a means for extracting and effectively utilizing the energy generated in the expander, and further, using the rotational energy obtained on the expansion turbine side, the compressor is utilized. By increasing the pressure of hydrogen gas on the side so that it is guided to the turbine inlet, the expansion ratio of the turbine increases by the amount of pressure boosted by the compressor, and more heat difference (= cold generation amount) is generated. You can get it.

Although the high pressure hydrogen expansion turbine type filling system of the present invention has been described above based on the embodiments thereof, the present invention is not limited to the configurations described in the above embodiments, and does not depart from the scope of the invention. The configuration can be changed appropriately.

The high-pressure hydrogen expansion turbine type filling system of the present invention has a simple structure, has a low burden of maintenance and management services, can reduce operating costs including the cost of power consumption, and is a general-purpose member as a constituent member of a hydrogen gas supply unit. Since it can be used, and it has the characteristics of smooth and efficient filling (shortening of the filling time) and improvement of the energy utilization efficiency of the equipment, the final filling of the hydrogen station is possible. It can be suitably used for the purpose of a hydrogen precooling system used for lowering the temperature of hydrogen gas in the section.

1 Compressor equipment 2 Hydrogen pressure storage equipment 3 Expansion valve
4 Hydrogen gas precooler 5 Hydrogen precooling system 6 Fuel tank (tank)
7 Refrigerator equipment 8 Brine circuit 9 Hydrogen gas source line 10 High pressure hydrogen expansion turbine type filling system 11 Expansion turbine (turbine / compressor)
11a turbine 11b compressor 12 cooler (aftercooler)
12a Cold heat source 13 Hydrogen gas supply unit 14 Regenerator 15 Heating heat source (external heating heat source)
16 regenerator

Claims

In a filling system that uses an expansion turbine to lower the enthalpy of hydrogen gas when pressure-filling hydrogen gas stored at a high pressure, a regenerator with a hydrogen storage alloy built in at the outlet of the expansion turbine and the regenerator An expansion turbine type filling system for high-pressure hydrogen, comprising: a heating heat source for heating the inside of the reactor.
The expansion turbine type filling system for high-pressure hydrogen according to claim 1, wherein a turbine compressor is used for the expansion turbine.
At the time of releasing the hydrogen gas of the hydrogen storage alloy, a high temperature fluid extracted from the exhaust heat side to the aftercooler of the turbine / compressor is guided to the regenerator containing the hydrogen storage alloy, and a circuit is returned to the aftercooler after heat exchange. The expansion turbine type filling system for high pressure hydrogen according to claim 2, wherein the filling system is provided.
When releasing the hydrogen gas of the hydrogen storage alloy, a circuit was provided for guiding the high temperature fluid extracted from the exhaust heat side of the hydrogen filling equipment to the regenerator containing the hydrogen storage alloy and returning it to the exhaust heat side after heat exchange. An expansion turbine type filling system for high-pressure hydrogen according to claim 1, 2 or 3.