Note: Descriptions are shown in the official language in which they were submitted.
1
HYDROGEN GAS GENERATING SYSTEM
FIELD OF THE INVENTION
[0001]
The invention relates to a hydrogen gas generating system
for producing a hydrogen gas.
BACKGROUND
[0002]
A hydrogen gas is used for a fuel of a fuel-cell vehicle,
for example. As the production of the fuel-cell vehicle is
expected to increase from now on, an increase in demand for
the hydrogen gas is anticipated. Accordingly, it is desired
to develop a technology for stably producing and supplying a
large volume of high-pressure hydrogen gases at a low cost.
[0003]
The hydrogen gas can be produced by electrolyzing the
seawater. Document 1 discloses a hydrogen gas occlusion system
in which DC electricity is generated by using the sunlight and
the seawater is electrolyzed with the use of the DC power, thereby
producing a hydrogen gas. The hydrogen gas occlusion system
includes a panel-shaped solar cell floated on the sea by the
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agency of a float, and a cassette with a hydrogen-occlusion
electrode incorporated therein, serving as a sinker, and
electrolyzes the seawater using the DC eloectricity generated
by the utilization of the sunlight. The hydrogen-occlusion
electrode is electrically coupled to a negative terminal of
the solar cell via a negative electrode. The seawater is
electrolyzed by using the hydrogen-occlusion electrode and a
positive electrode electrically coupled to a positive terminal
of the solar cell. Hydrogen that is generated through the
electrolyzation of the seawater is occluded in the
hydrogen-occlusion electrode. In the hydrogen gas occlusion
system disclosed in Document 1, the cassette incorporating the
hydrogen-occlusion electrode is removable from the system and
hydrogen can be taken out by removing and heating the cassette.
[0004]
Document 1: JP 2008-174771
SUMMARY
[0005]
With a conventional method for electrolyzing seawater
by using a DC power generated by the solar cell, as in Document
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1, hydrogen can be produced at a low cost. However, this method
is disadvantageous in that a volume of high-pressure hydrogen
gases generated and available for supply will be unstable under
the influence of variation in solar energy since a voltage and
a current of generated electricity largely varies when the
intensity of the sunlight varies.
[0006]
Further, the method in which the hydrogen gas occlusion
system is floated on the sea surface, as in Document 1, is easily
affected not only by movement of the sea surface due to waves
and an ocean current but also by large waves due to a typhoon,
etc., rendering it difficult to securely hold the hydrogen gas
occlusion system. Therefore, the method may have difficulty
in stably producing a large volume of hydrogen gases.
[0007]
With use of the hydrogen gas occlusion system disclosed
in Document 1, it is necessary to have a multitude of the hydrogen
gas occlusion systems floated on the sea surface in order to
produce a large volume of hydrogen gases. The method is
therefore disadvantageous in that there is the need for removing
the cassette from the multitude of the hydrogen gas occlusion
systems to take out the hydrogen from the hydrogen-occlusion
electrode and the need for substituting a cassette incorporating
the hydrogen-occlusion electrode containing no hydrogen
therein for a removed cassette. So, the hydrogen gas occlusion
4
system disclosed in Document 1 involves a challenge that much
cost and labor are required for producing and supplying the
hydrogen gases
[0008]
As describe above, conventional technologies are
disadvantageous in that it is difficult to stably produce and
supply a large volume of the high-pressure hydrogen gases at
a low cost . It is an object of the invention to provide a hydrogen
gas generating system which stably produces and supplies a large
volume of high-pressure hydrogen gases at a low cost.
[0008a]
Certain exemplary embodiments can provide a hydrogen gas
generating system comprising: a photovoltaic power generation
unit for generating DC electricity, including a solar cell; a
seawater electrolyzation unit for generating a hydrogen gas
by electrolyzing seawater with the use of the DC electricity
generated by the photovoltaic power generation unit, including
a first hydrogen gas tank; a solar thermal power generation
unit for generating AC electricity by rotating a turbine with
the use of a steam generated by utilizing solar heat; a hydrogen
gas compressor for compressing the hydrogen gas generated by
the seawater electrolyzation unit, the hydrogen gas compressor
being driven by the AC electricity generated by the solar thermal
power generation unit; and a second hydrogen gas tank, wherein:
the seawater electrolyzation unit is configured to store the
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generated hydrogen gas in the first hydrogen gas tank; and
the hydrogen gas compressor is configured to (i) compress the
hydrogen gas stored in the first hydrogen gas tank and (ii)
store the compressed hydrogen gas in the second hydrogen gas
tank.
[0009]
According to another embodiment, a hydrogen gas
generating system includes a photovoltaic power generation unit
for generating DC electricity, including a solar cell; a seawater
electrolyzation unit for generating a hydrogen gas by
electrolyzing seawater with the use of the DC electricity
generated by the photovoltaic power generation unit; a solar
thermal power generation unit for generating AC electricity
by rotating a turbine with the use of a steam generated by
utilizing solar heat; and a hydrogen gas compressor for
compressing the hydrogen gas generated by the seawater
electrolyzation unit, the hydrogen gas compressor being driven
by the AC electricity generated by the solar thermal power
generation unit.
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[0010]
The present invention provides a hydrogen gas generating
system which stably produces and supplies a large volume of
high-pressure hydrogen gases at a low cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
Fig. 1 is a view showing an overall configuration of a
hydrogen gas generating system according to an embodiment of
the present invention;
Fig. 2 is a view showing a configuration of a seawater
electrolyzation unit of the hydrogen gas generating system
according to the present embodiment; and
Fig. 3 is a view showing a configuration of a solar thermal
power generation unit of the hydrogen gas generating system
according to the present embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012]
A hydrogen gas generating system according to the present
invention is installed on the ground and includes a photovoltaic
power generation unit, a seawater electrolyzation unit to use
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DC electricity generated by the photovoltaic power generation
unit, a solar thermal power generation unit, and a high-pressure
gas compressor to be driven by AC electricity generated by the
solar thermal power generation unit. The hydrogen gas
generating system can stably producing and supplying a large
volume of the high-pressure hydrogen gases at a low cost by
allowing the seawater electrolyzation unit to electrolyze the
seawater to generate a hydrogen gas and the high-pressure gas
compressor to compress the generated low-pressure hydrogen
gases. Further, the hydrogen gas generating system according
to the present invention can compress the low-pressure chlorine
gas generated by the electrolyzation of seawater by using a
high-pressure gas compressor, so that a large volume of the
high-pressure chlorine gases are stably produced and supplied
at a low cost. The low-pressure hydrogen gas and the
low-pressure chlorine gas, generated by the electrolyzation,
are once stored in respective low-pressure tanks, to be
subsequently compressed by the respective high-pressure gas
compressors before being stored in respective high-pressure
tanks. In the present invention, because the DC electricity
generated by the photovoltaic power generation unit is utilized
for the electrolyzation of seawater and the AC electricity
generated by the solar thermal power generation unit is utilized
for the compression of the hydrogen gas and the chlorine gas,
it is possible to produce and supply the high-pressure hydrogen
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gas and the high-pressure chlorine gas at a low cost.
Furthermore, because the hydrogen gas generating system
according to the present invention is installed on the ground,
not on the sea surface, it is possible to stably execute the
electrolyzation and the compression of the gases without being
affected by waves, leading to stable produce and supply of a
large volume of the high-pressure hydrogen gases and the
high-pressure chlorine gases.
[0013]
As descried above, in the conventional method for
electrolyzing seawater with the use of the DC power generated
by the solar cell, a volume of the hydrogen gases that are
generated and supplied is unstable due to variation in solar
energy since the voltage and the current of the generated
electricity varies according to the intensity of the sunlight.
The present invention is advantageous in that it is possible
to suppress the variation in energy obtained from the solar
energy even if the variation occurs in the solar energy and
to stably supply the high-pressure hydrogen gas and the
high-pressure chlorine gas since the solar energy is converted
into the energies of the high-pressure hydrogen gas and the
high-pressure chlorine gas and stored in respective
high-pressure tanks. Further, because the low-pressure
hydrogen gas and the low-pressure chlorine gas generated by
the electrolyzation of seawater are compressed by the
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high-pressure gas compressors utilizing the AC electricity
generated by the solar thermal power generation unit, it is
possible to produce a large volume of the high-pressure hydrogen
gases and the high-pressure chlorine gases at a low cost.
[0014]
Thus, the hydrogen gas generating system according to
the present invention, which is installed on the ground and
uses seawater available at a low cost and two types of the solar
energies, sunlight and solar heat, can make the most of
synergistic advantageous effects of the electrolyzation of the
seawater using the sun light and the solar thermal power
generation using the seawater, and can stably produce and supply
a large volume of the high-pressure hydrogen gases and the
high-pressure chlorine gases at a low cost.
[0015]
In the hydrogen gas generating system according to the
present invention, it is possible to continuously operate the
seawater electrolyzation unit and the high-pressure gas
compressor during the daytime to continuously produce a large
volume of hydrogen gases and chlorine gases at a low price.
Seawater serving as raw materials of the hydrogen gas and the
chlorine gas is nearly limitlessly present in nature so that
there is no possibly that the seawater will be in short supply.
In the present invention, since solar energy available at no
cost is utilized, a large volume of inexpensive high-pressure
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hydrogen gases and high-pressure chlorine gases can be produced
and supplied without generating a carbon-dioxide gas by burning
a fossil fuel. The produced high-pressure hydrogen gas can
be supplied to, for example, a fuel-cell vehicle consuming a
large volume of hydrogen gases. Although a fuel-cell vehicle
is expensive at present, the fuel-cell vehicle will be
mass-produced in several years and the price of it will come
down, and the demand for the hydrogen gas as the fuel is expected
to increase from now on. Furthermore, the chlorine gas is in
demand as a raw material for various disinfectants and chemical
products.
[0016]
In the hydrogen gas generating system according to the
present invention, a hydrogen gas and a chlorine gas generated
by the seawater electrolyzation unit are once stored in the
respective low-pressure tanks as low-pressure gases without
being compressed and then compressed by the respective
high-pressure gas compressors. Accordingly, even if total
irradiance from the sun varies due to a change in weather during
the daytime, the generated power of the solar power generation
(the solar cell) is varied, and then a volume or a pressure
of the hydrogen gases and the chlorine gases generated from
the seawater electrolyzation unit varies, a variance in pressure
of the hydrogen gases and the chlorine gases in the respective
low-pressure tanks can be controlled to fall within a given
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range dependent on the volume of the low-pressure tanks.
Further, even if direct irradiance from the sun largely varies
due to a change in weather during the daytime and the generated
power of the solar thermal power generation is varied, and then
5 a volume of the hydrogen gases and the chlorine gases compressed
by the hydrogen gas compressors varies, a variance in the
pressure of the hydrogen gases and the chlorine gases in the
respective high-pressure tanks can be controlled to fall within
a given range dependent on the volume of the high-pressure tanks.
10 In the present invention, it is possible to suppress variation
in the energy obtained from the solar energy by adopting the
above-described method even if the solar energy varies.
[0017]
Furthermore, seawater used as a cooling water of the solar
thermal power generation unit (a warm discharged water ejected
from a condenser) can be used for the seawater to be electrolyzed
by the seawater electrolyzation unit. By reusing a portion
of the warm discharged water of the condenser of the solar thermal
power generation unit for a raw material of the seawater
electrolyzation unit (seawater for the electrolyzation) ,
decomposition activity of the seawater electrolyzation unit
is increased and, therefore, electric power is decreased
required for the electrolyzation to produce the hydrogen gas
and the chlorine gas.
[0018]
=
11
The hydrogen gas generating system according to an
embodiment of the present invention is described below with
reference to the drawings. Problems to be solved,
configurations, and effects of the present invention other than
described above will be described in the following description
of an embodiment of the invention.
EMBODIMENT
[0019]
Fig. 1 is a view showing an overall configuration of a
hydrogen gas generating system 100 according to an embodiment
of the present invention. The hydrogen gas generating system
100 according to the present embodiment is installed on the
ground and includes, as the main elements, a photovoltaic power
generation unit 3, a seawater electrolyzation unit 200, a solar
thermal power generation unit 300, a high-pressure hydrogen
gas compressor 101, and a high-pressure chlorine gas compressor
102. The hydrogen gas generating system100 is capable of stably
producing and supplying a large volume of high-pressure hydrogen
gases and high-pressure chlorine gases at a low cost. The
photovoltaic power generation unit 3 includes a solar cell and
generates a DC power through photovoltaic power generation by
the solar cell. The seawater electrolyzation unit 200
electrolyzes seawater and produces a hydrogen gas and a chlorine
gas by using the DC electricity generated by the photovoltaic
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power generation unit 3. The solar thermal power generation
unit 300 generates AC electricity by rotating a turbine with
a steam generated using solar-heat. The high-pressure hydrogen
gas compressor 101 is driven by a high-pressure hydrogen gas
compressor motor 88 and compresses the hydrogen gas generated
by the seawater electrolyzation unit 200 with the use of the
AC electricity generated by the solar thermal power generation
unit 300. The high-pressure chlorine gas compressor 102 is
driven by a high-pressure chlorine gas compressor motor 89 and
compresses the chlorine gas generated by the seawater
electrolyzation unit 200 with the use of the AC electricity
generated by the solar thermal power generation unit 300.
[0020]
Fig. 2 is a view showing a configuration of the seawater
electrolyzation unit 200 of the hydrogen gas generating system
100 according to the present embodiment. The seawater
electrolyzation unit 200 includes, as the main elements, a
seawater electrolytic bath 4, a low-pressure hydrogen gas tank
36, and a low-pressure chlorine gas tank 46. The seawater
electrolytic bath 4 electrolyzes seawater and produces the
hydrogen gas and the chlorine gas by using the DC electricity
generated by the photovoltaic power generation unit 3. The
low-pressure hydrogen gas tank 36 stores the hydrogen gas
generated in the seawater electrolytic bath 4 without
application of pressure. The low-pressure chlorine gas tank
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46 stores the chlorine gas generated in the seawater electrolytic
bath 4 without application of pressure.
[0021]
Fig. 3 is a view showing a configuration of the solar
thermal power generation unit 300 of the hydrogen gas generating
system 100 according to the present embodiment. The solar
thermal power generation unit 300 includes, as the main elements,
a solar-heat receiver 52, a high-pressure steam turbine 54,
an intermediate/low-pressure steam turbine 58, a generator 29,
and a condenser 60. The high-pressure steam turbine 54 and
the intermediate/low-pressure steam turbine 58 are rotated by
a superheated steam generated by the solar-heat receiver 52,
and thereby the generator 29 generates the AC electricity. The
superheated steam that has rotated the steam turbines 54 and
58 is cooled by seawater in the condenser 60.
[0022]
For the seawater to be electrolyzed by the seawater
electrolyzat ion unit 200, a warmed seawater can be used which
is already used and warmed in the condenser 60 of the solar
thermal power generation unit 300. Furthermore, a seawater
can be used which is in a seawater-intake basin 16 for taking
in seawater to be used in the condenser 60 or in a
seawater-discharge basin 98 for discharging the seawater
already used in the condenser 60. A large volume of the seawater
for the electrolyzation can be supplied to the seawater
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electrolytic bath 4 in this way.
[0023]
The seawater electrolyzation unit 200 and the solar
thermal power generation unit 300 of the hydrogen gas generating
system 100 according to the present embodiment are described
below in detail with reference to Figs. 1 to 3.
[0024]
First, the seawater electrolyzation unit 200 is described
below.
[0025]
As shown in Fig. 2, the seawater electrolytic bath 4 of
the seawater electrolyzation unit 200 includes a cathode-bath
9, an anode-bath 10, a hydrogen gas generator 5, and a chlorine
gas generator 6. The cathode-bath 9 and the anode-bath 10
contain seawater and are connected with each other via a
communication-adjust pipe 150. The communication-adjust pipe
150 includes an anode-cathode-bath flow-rate balance valve 15
and flows seawater between the cathode-bath 9 and the anode-bath
10.
[0026]
An anode-cathode-bath flow-rate balance valve 15 can
control a volume of the seawater flowing through the
communication-adjust pipe 150, thereby controlling seawater
volumes of the cathode-bath 9 and the anode-bath 10. The
electrolyzation of the seawater causes the hydrogen gas to be
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generated in the cathode-bath 9 and the chlorine gas to be
generated in the anode-bath 10. As the electrolyzation of the
seawater progresses, the volumes of the seawater of the
cathode-bath 9 and the anode-bath 10 will decrease. Since the
5 decreased volumes of the seawater are different between the
cathode-bath 9 and the anode-bath 10, there occurs a difference
in the seawater volume between the cathode-bath 9 and the
anode-bath 10. Accordingly, the anode-cathode-bath flow-rate
balance valve 15 adjusts the volume of the seawater flowing
10 through the communication-adjust pipe 150 in response to the
volume of the decrease in the seawater and controls the
difference to be small between the seawater volumes of the
cathode-bath 9 and the anode-bath 10.
[00271
15 The hydrogen gas generator 5 includes a cathode 7 installed
in the seawater contained in the cathode-bath 9 and a hydrogen
gas recovery unit 27. The chlorine gas generator 6 includes
an anode 8 installed in the seawater contained in the anode-bath
10 and a chlorine gas recovery unit 28. The hydrogen gas recovery
unit 27 is made of, for example, a cylindrical container with
the top end closed and the bottom end open, and the top part
is connected to a hydrogen gas recovery unit outlet-pipe 31,
and the bottom part is submerged below the seawater surface
of the cathode-bath 9. The chlorine gas recovery unit 28 is
made of, for example, a cylindrical container with the top end
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closed and the bottom end open, and the top part is connected
to a chlorine gas recovery unit outlet-pipe 41, and the bottom
part is submerged below the seawater surface of the anode-bath
10.
[00281
The photovoltaic power generation unit 3 generates the
DC electricity by using the radiant energy of a sunlight beam
2 radiated from the sun 1. The cathode of the photovoltaic
power generation unit 3 is connected to the cathode 7 of the
seawater electrolytic bath 4 via a cathode electric-wire 11.
The anode of the photovoltaic power generation unit 3 is
connected to the anode 8 of the seawater electrolytic bath 4
via an anode electric-wire 12. When the seawater in the seawater
electrolytic bath 4 is electrolyzed by the DC electricity
generatedby the photovoltaic power generation unit 3, a hydrogen
gas bubble 30 is generated around the cathode 7 in the hydrogen
gas generator 5, and a chlorine gas bubble 40 is generated around
the anode 8 in the chlorine gas generator 6.
[0029]
A hydrogen gas generated in the hydrogen gas generator
5 is recoveredby the hydrogen gas recoveryunit 27. The hydrogen
gas recovery unit 27 collects the hydrogen gas generated by
the electrolyzation above the seawater surface in the
cylindrical container. The collected hydrogen gas is collected
in a hydrogen gas outlet header 33 after passing through the
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hydrogen gas recovery unit outlet-pipe 31 and a hydrogen gas
recovery unit outlet-valve 32. The collected hydrogen gas is
once stored in the low-pressure hydrogen gas tank 36 as
low-pressure hydrogen gas without application of pressure after
passing through a low-pressure hydrogen gas tank
pressure-adjust valve 34 and a low-pressure hydrogen gas tank
inlet pipe 35. A pressure of the low-pressure hydrogen gas
tank 36 is detected by a low-pressure hydrogen gas tank pressure
gage 38. By opening/closing the low-pressure hydrogen gas tank
pressure-adjust valve 34 in response to a generation volume
of the hydrogen gas, the pressure of the low-pressure hydrogen
gas tank 36 is controlled to fall within a predetermined range.
When a predetermined volume of the hydrogen gas is accumulated
in the low-pressure hydrogen gas tank 36, the hydrogen gas is
sent out to the high-pressure hydrogen gas compressor 101 from
the low-pressure hydrogen gas tank 36 through a hydrogen gas
compressor inlet pipe 37.
[0030]
A chlorine gas generated in the chlorine gas generator
6 is recovered by the chlorine gas recovery unit 28 . The chlorine
gas recovery unit 28 collects the chlorine gas generated by
the electrolyzation above the seawater surface in the
cylindrical container. The collected chlorine gas is collected
in a chlorine gas outlet header 43 after passing through the
chlorine gas recovery unit outlet-pipe 41 and a hydrogen gas
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recovery unit outlet-valve 42. The collected hydrogen gas is
once stored in the low-pressure chlorine gas tank 46 as
low-pressure chlorine gas without application of pressure after
passing through a low-pressure chlorine gas tank
pressure-adjust valve 44 and a low-pressure chlorine gas tank
inlet pipe 45. A pressure of the low-pressure chlorine gas
tank 46 is detected by a low-pressure chlorine gas tank pressure
gage 48. By opening/closing the low-pressure chlorine gas tank
pressure-adjust valve 44 in response to a generation volume
of the chlorine gases, the pressure of the low-pressure chlorine
gas tank 46 is controlled to fall within a predetermined range.
When a predetermined volume of the chlorine gas is accumulated
in the low-pressure chlorine gas tank 46, the chlorine gas is
sent out to the high-pressure chlorine gas compressor 102 from
the low-pressure chlorine gas tank 46 through a chlorine gas
compressor inlet pipe 47.
[0031]
The seawater to be electrolyzed in the seawater
electrolytic bath 4 of the seawater electrolyzation unit 200
is supplied from at least one of the seawater-intake basin 16,
the seawater-discharge basin 98, and the condenser 60 of the
solar thermal power generation unit 300, as shown in Figs. 2
and 1. The seawater-intake basin 16 is a facility for containing
the seawater to be used in the condenser 60. The seawater used
in the condenser 60 is taken in from the seawater-intake basin
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16. The seawater-discharge basin 98 is a facility for
containing the seawater already used in the condenser 60. The
seawater already used in the condenser 60 is discharged into
the seawater-discharge basin 98. The seawater is supplied from
the seawater-intake basin 16 by use of a seawater pump 18
installed in the vicinity of the seawater-intake basin 16, from
the seawater-discharge basin 98 by use of a seawater pump 118
installed in the vicinity of the seawater-discharge basin 98,
and from the condenser 60 by use of a seawater boost pump 99.
[0032]
The seawater in the seawater-intake basin 16 flows through
a seawater-pump inlet pipe 21, passing through a seawater-pump
inlet valve 17, to the seawater pump 18 to be boosted. The
boosted seawater is sent out to a seawater header 26, passing
through a seawater-pump outlet check-valve 19, a seawater-pump
outlet valve 20, and a seawater-pump outlet pipe 22.
[0033]
The seawater in the seawater-discharge basin 98 flows
through a seawater-pump inlet-pipe 121, passing through a
seawater-pump inlet-valve 117, to the seawater pump 118 to be
boosted. The boosted seawater is sent out to the seawater header
26, passing through a seawater-pump outlet check-valve 119,
a seawater-pump outlet-valve 120, and a seawater-pump
outlet-pipe 122.
[0034]
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The seawater supplied from the condenser 60 to the seawater
electrolytic bath 4 is a warm seawater obtained by cooling the
steam in the condenser 60 . As shown in Figs . 1 and 3 , the seawater
ejected from the condenser 60 (the warm discharged-water) flows
5 through a condenser-outlet circulating-water pipe 94. Themost
of the seawater flows through a seawater-discharge basin
circulating-water valve 96 and a seawater-discharge basin
inlet-pipe 97 to the seawater-discharge basin 98 and is
subsequently discharged into the sea. The remainder of the
10 seawater is taken out from the condenser-outlet
circulating-water pipe 94 at a seawater-electrolyzation-unit
seawater take-out valve 95, passes through a seawater boost
pump inlet-valve 39, and is boosted by a seawater boost pump
99. The boosted seawater (the warm discharged-water) passes
15 through a seawater boost pump outlet check-valve 49 and a
seawater boost pump outlet-valve 79 and flows through a seawater
boost pump outlet pipe 25 to the seawater header 26.
[0035]
As shown in Fig. 2, these seawaters delivered to the
20 seawater header 26 are divided into two systems, one flowing
through a cathode-bath seawater flow-rate control valve inlet
pipe 23, and the other flowing through an anode-bath seawater
flow-rate control valve inlet pipe 24. The seawater flowing
through the cathode-bath seawater flow-rate control valve inlet
pipe 23 is delivered to the cathode-bath 9 after passing through
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a cathode-bath seawater flow-rate control valve 13. The
seawater flowing through the anode-bath seawater flow-rate
control valve inlet pipe 24 is delivered to the anode-bath 10
after passing through an anode-bath seawater flow-rate control
valve 14.
[0036]
Next, the solar thermal power generation unit 300 is
described below.
[0037]
Fig. 3 shows the solar thermal power generation unit 300
adopting a tower-style solar-heat collecting method . However,
the solar thermal power generation unit 300 can adopt any
solar-heat collecting method (for example, trough-type,
Fresnel-type, and a combination of several types, etc.) in the
hydrogen gas generating system according to the present
invention.
[0038]
As shown in Figs. 3 and 1, in the solar thermal power
generation unit 300, the solar-heat energy conveyed from the
sun 1 with the sunlight beam 2 is reflected by a multitude of
heliostats 51 disposed around a tower 74 and collected in the
solar-heat receiver 52. A feed-water heated by the steam at
a high-pressure heater 56 and flowed through a solar-heat
collector feed-water pipe 50 is supplied to the tower 74. The
steam extracted from the high-pressure steam turbine 54 flows
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into the high-pressure heater 56 after passing through a
high-pressure heater extraction pipe 55. The extracted steam
heats the feed-water flowed into the high-pressure heater 56
by a feed-water pump 64.
[0039]
The feed-water supplied to the tower 74 is heated by the
solar-heat energy at the solar-heat receiver 52 and is turned
into the superheated steam. The superheated steam flows
through a solar-heat collector outlet header 53, rotates the
high-pressure steam turbine 54, flows through a communication
pipe 57, and rotates the intermediate/low-pressure steam
turbine 58. These steam turbines rotates the generator 29
directly connected to the turbines, thereby generating the AC
electricity. The AC electricity is transmitted to a
high-pressure system bus 82 via a main transformer 80 and a
main circuit-breaker 81.
[0040]
The steam exhausted from the intermediate/low-pressure
steam turbine 58 flows through a low-pressure steam turbine
exhaust-pipe 59 and flows into the condenser 60. The steam
flowed into the condenser 60 is cooled by the seawater flowed
through a condenser-inlet circulating-water pipe 93 and turned
into a steam condensate. The steam condensate flows through
a steam-condensate pipe 67 into a steam-condensate pump 68,
is boosted in the steam-condensate pump 68, is heated by a
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low-pressure heater 69, enters a deaerator 63 after passing
through a deaerator-inlet pipe 70, and is heated and deaerated
by the deaerator 63. In order to heat the steam condensate,
the steam extracted from the intermediate/low-pressure steam
turbine 58 flows into the low-pressure heater 69 via a
low-pressure steam extraction pipe 62. In order to heat and
deaerate the steam condensate, the steam extracted from the
high-pressure steam turbine 54 flows into the deaerator 63 via
a deaerator steam-extraction pipe 61. The steam condensate
deaerated in the deaerator 63 is boosted by a feed-water pump
64, passes through a feed-water flow-rate adjust valve 65 and
a feed-water pump outlet-pipe 66, and flows to the high-pressure
heater 56 where the steam condensate turns into the feed water
to be supplied to the tower 74. That is, water flowed from
the deaerator 63 to the high-pressure heater 56 is heated by
the steam extracted from the high-pressure steam turbine 54,
flows through the solar-heat collector feed-water pipe 50, is
sent to the tower 74, and turns into the superheated steam by
the solar-heat energy.
[0041]
The seawater (the cooling water) flowing into the
condenser 60 after flowing through the condenser-inlet
circulating-water pipe 93 is taken out from the seawater-intake
basin 16. Theseawaterintheseawater-intakebasinl6istaken
out through a circulating-water pump inlet-pipe 90, is boosted
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by a circulating-water pump 91, passes through a
circulating-water pump outlet-valve 92, flows through the
condenser-inlet circulating-water pipe 93, and flows into the
condenser 60. The seawater (the cooling water) flowed into
the condenser 60 cools the steam flowed into the condenser 60.
As described above, the cooling water (the warm
discharged-water) heated by cooling the steam flows through
the condenser-outlet circulating-water pipe 94. A portion of
the cooling water passes through the seawater-discharge basin
circulating-water valve 96 and the seawater-discharge basin
inlet pipe 97 and flows to the seawater-discharge basin 98.
A portion of the remainder of the cooling water flows through
the seawater-electrolyzation-unit seawater take-out valve 95
and the seawater boost pump inlet valve 39, is boosted by the
seawater boost pump 99, flows through the seawater boost pump
outlet check-valve 49, the seawater boost pump outlet valve
79, and the seawater boost pump outlet pipe 25, is supplied
to the seawater electrolytic bath 4, and is used as the seawater
to be electrolyzed in the seawater electrolytic bath 4.
[0042]
Referring to Fig. 1, the hydrogen gas generating system
100 according to the present embodiment is described below on
the basis of description given on the seawater electrolyzation
unit 200 and the solar thermal power generation unit 300. The
hydrogen gas generating system 100 further includes a
CA 02944428 2016-09-29
high-pressure hydrogen gas tank 103 and a high-pressure chlorine
gas tank 104, as described later on.
[0043]
The AC electricity generated by the generator 29 of the
5 solar thermal power generation unit 300 is boosted in voltage
at the main transformer 80 and subsequently transmitted to the
high-pressure system bus 82 after passing through the main
circuit-breaker 81. A portion of the AC electricity passes
through a house circuit-breaker 83 and drops in voltage at a
10 house transformer 84. A portion of the AC electricity with
the dropped voltage passes through a high-pressure hydrogen
gas compressor circuit-breaker 85 and is transmitted to a
high-pressure hydrogen gas compressor motor 88. Another
portion of the AC electricity with the dropped voltage passes
15 through a high-pressure chlorine gas compressor
circuit-breaker 86 and is transmitted to a high-pressure
chlorine gas compressor motor 89. Another portion of the AC
electricitywith the droppedvoltage passes through an auxiliary
circuit-breaker 87 and is transmitted to the motors of auxiliary
20 devices of the seawater electrolyzation unit 200 and the solar
thermal power generation unit 300.
[0044]
The high-pressure hydrogen gas compressor motor 88 drives
the high-pressure hydrogen gas compressor 101. The
25 high-pressure hydrogen gas compressor 101 is connected to the
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26
low-pressure hydrogen gas tank 36and a high-pressure hydrogen
gas tank 103, compressing the hydrogen gas stored in the
low-pressure hydrogen gas tank 36, and storing the compressed
hydrogen gas in the high-pressure hydrogen gas tank 103. The
hydrogen gas is compressed up to a pressure corresponding to
usage thereof, for example, up to a high pressure of about 7
to 70 MPa.
[0045]
The high-pressure chlorine gas compressor motor 89 drives
the high-pressure chlorine gas compressor 102. The
high-pressure chlorine gas compressor 102 is connected to the
low-pressure chlorine gas tank 46and a high-pressure chlorine
gas tank 104, compressing the chlorine gas stored in the
low-pressure chlorine gas tank 46, and storing the compressed
chlorine gas is the high-pressure chlorine gas tank 104. The
chlorine gas is compressed up to a pressure corresponding to
usage thereof.
[0046]
For compressions of the hydrogen gas and the chlorine
gas, an abundance of electric power, on the order of MW, is
required. In the hydrogen gas generating system 100 according
to the present embodiment, such an abundance of electric power
is acquired from the solar energy, not from a fossil fuel.
Therefore, it is possible to produce a large volume of the
high-pressure hydrogen gas and the high-pressure chlorine gas
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27
at a low cost with substantial reduction in generation of
carbon-dioxide gas.
[0047]
The high-pressure hydrogen gas delivered from the
high-pressure hydrogen gas compressor 101 is stored in the
high-pressure hydrogen gas tank 103 after passing through a
high-pressure hydrogen gas-tank pressure-adjust valve 105. A
pressure of the high-pressure hydrogen gas tank 103 is detected
by a high-pressure hydrogen gas-tank pressure-gage 107. By
opening/closing the high-pressure hydrogen gas-tank
pressure-adjust valve 105 and altering a flow rate of the
hydrogen gas flowing into the high-pressure hydrogen gas tank
103, the pressure of the high-pressure hydrogen gas tank 103
is controlled to fall within a predetermined range. Further
higher-pressure hydrogen gas can be obtained by taking out
hydrogen gas from the intermediate stage of the high-pressure
hydrogen gas compressor 101 and cooling the taken hydrogen gas
using a coolant, such as seawater, etc. The high-pressure
hydrogen gas stored in the high-pressure hydrogen gas tank 103
is taken out by using a high-pressure hydrogen gas take-out
adjust-valve 109 and is stored in a high-pressure hydrogen gas
cylinder 75. The high-pressure hydrogen gas cylinder 75 is
carried out by using a high-pressure hydrogen gas transport
vehicle 77. The hydrogen gas generating system according to
the present invention is capable of supplying the high-pressure
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28
hydrogen gas to users in a way described above.
[0048]
The high-pressure chlorine gas delivered from the
high-pressure chlorine gas compressor 102 is stored in the
high-pressure chlorine gas tank 104 after passing through a
high-pressure chlorine gas-tank pressure-adjust valve 106. A
pressure of the high-pressure chlorine gas tank 104 is detected
by a high-pressure chlorine gas-tank pressure-gage 108. By
opening/closing the high-pressure chlorine gas-tank
pressure-adjust valve 106 and altering a flow rate of the
chlorine gas flowing into the high-pressure chlorine gas tank
104, the pressure of the high-pressure chlorine gas tank 104
is controlled to fall within a predetermined range. Further
higher-pressure chlorine gas can be obtained by taking out
chlorine gas from the intermediate stage of the high-pressure
chlorine gas compressor 102 and cooling the taken chlorine gas
using a coolant, such as seawater, etc. The high-pressure
chlorine gas stored in the high-pressure chlorine gas tank 104
is taken out by using a high-pressure chlorine gas take-out
adjust-valve 110 and is stored in a high-pressure chlorine gas
cylinder 76. The high-pressure chlorine gas cylinder 76 is
carried out by using a high-pressure chlorine gas transport
vehicle 78. The hydrogen gas generating system according to
the present invention is capable of supplying the high-pressure
chlorine gas to users in a way described as above.
CA 02944428 2016-09-29
29
[0049]
As described above, the hydrogen gas generating system
100 according to the present embodiment utilizes the AC
electricity generated with use of the solar-heat energy without
burning the fossil fuel as a power supply for driving the
high-pressure hydrogen gas compressor 101 and the high-pressure
chlorine gas compressor 102, therefore the system 100 can
generate the AC electricity without releasing a carbon-dioxide
gas due to combustion of the fossil fuel into the atmosphere.
[0050]
Further, the hydrogen gas generating system 100 according
to the present embodiment utilizes a portion of the seawater
(the warm discharged water) heated by cooling the steam in the
condenser 60 as the seawater to be electrolyzed in the seawater
electrolytic bath 4, as shown in Figs. 1 to 3. The system 100
has an advantage in that energy consumed in the electrolyzation
of seawater can be reduced by using the warm seawater as the
seawater to be electrolyzed.
[0051]
In general, seawater in nature is available at no cost.
A massive volume of seawater exists on Earth, and therefore,
it can be said that seawater can be unlimitedly found as far
as used for a raw material for the electrolyzation. Accordingly,
the hydrogen gas generating system 100 according to the present
embodiment also can send out the seawater taken out from the
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seawater-intake basin 16 directly to the seawater electrolytic
bath 4 without using the seawater as cooling water of the solar
thermal power generation unit 300, as shown in Figs. 1 to 3.
A method for sending out the seawater taken out from the
5 seawater-intake basin 16 directly to the seawater electrolytic
bath 4 has an advantage in that a large volume of seawater can
be used for the electrolyzation, leading to a mass production
of the hydrogen gas and the chlorine gas.
10 EXPLANATION OF REFERENCE CHARACTERS
[0052]
1: the sun,
2: sunlight beam,
3: photovoltaic power generation unit,
15 4: seawater electrolytic bath,
5: hydrogen gas generator,
6: chlorine gas generator,
7: cathode of seawater electrolytic bath,
8: anode of seawater electrolytic bath,
20 9: cathode-bath,
10: anode-bath,
11: cathode electric-wire,
12: anode electric-wire,
13: cathode-bath seawater flow-rate control valve,
25 14: anode-bath seawater flow-rate control valve,
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15: anode-cathode-bath flow-rate balance valve,
16: seawater-intake basin,
17: seawater-pump inlet valve,
18: seawater pump,
19: seawater-pump outlet check-valve,
20: seawater-pump outlet valve,
21: seawater-pump inlet pipe,
22: seawater-pump outlet pipe,
23: cathode-bath seawater flow-rate control valve inlet pipe,
24: anode-bath seawater flow-rate control valve inlet pipe,
25: seawater boost pump outlet pipe,
26: seawater header,
27: hydrogen gas recovery unit,
28: chlorine gas recovery unit,
29: generator,
30: bubble of hydrogen gas,
31: hydrogen gas recovery unit outlet-pipe,
32: hydrogen gas recovery unit outlet-valve,
33: hydrogen gas outlet header,
34: low-pressure hydrogen gas tank pressure-adjust valve,
35: low-pressure hydrogen gas tank inlet pipe,
36: low-pressure hydrogen gas tank,
37: hydrogen gas compressor inlet pipe,
38: low-pressure hydrogen gas tank pressure gage,
39: seawater boost pump inlet-valve,
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40: bubble of chlorine gas,
41: chlorine gas recovery unit outlet-pipe,
42: hydrogen gas recovery unit outlet-valve,
43: chlorine gas outlet header,
44: low-pressure chlorine gas tank pressure-adjust valve,
45: low-pressure chlorine gas tank inlet pipe,
46: low-pressure chlorine gas tank,
47: chlorine gas compressor inlet,
48: low-pressure chlorine gas pressure gage,
49: seawater boost pump outlet check-valve,
50: solar-heat collector feed-water pipe,
51: heliostat,
52: solar-heat receiver
53: solar-heat collector outlet header,
54: high-pressure steam turbine,
55: high-pressure heater extraction pipe,
56: high-pressure heater,
57: communication pipe,
58: intermediate/low-pressure steam turbine,
59: low-pressure steam turbine exhaust-pipe,
60: condenser,
61: deaerator steam-extraction pipe,
62: low-pressure steam extraction pipe,
63: deaerator,
64: feed-water pump,
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65: feed-water flow-rate adjust valve,
66: feed-water pump outlet-pipe,
67: steam-condensate pipe,
68: steam-condensate pump,
69: low-pressure heater,
70: deaerator-inlet pipe,
74: tower,
75: high-pressure hydrogen gas cylinder,
76: high-pressure chlorine gas cylinder,
77: high-pressure hydrogen gas transport vehicle,
78: high-pressure chlorine gas transport vehicle,
79: seawater boost pump outlet-valve,
80: main transformer,
81: main circuit-breaker,
82: high-pressure system bus,
83: house circuit-breaker,
84: house transformer,
85: high-pressure hydrogen gas compressor circuit-breaker,
86: high-pressure chlorine gas compressor circuit-breaker,
87: auxiliary circuit-breakers,
88: high-pressure hydrogen gas compressor motor,
89: high-pressure chlorine gas compressor motor,
90: circulating-water pump inlet-pipe
91: circulating-water pump,
92: circulating-water pump outlet-valve,
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93: condenser-inlet circulating-water pipe,
94: condenser-outlet circulating-water pipe,
95: seawater-electrolyzation-unit seawater take-out valve,
96: seawater-discharge basin circulating-water valve,
97: seawater-discharge basin inlet-pipe,
98: seawater-discharge basin,
99: seawater boost pump,
100: hydrogen gas generating system,
101: high-pressure hydrogen gas compressor,
102: high-pressure chlorine gas compressor,
103: high-pressure hydrogen gas tank,
104: high-pressure chlorine gas tank,
105: high-pressure hydrogen gas-tank pressure-adjust valve,
106: high-pressure chlorine gas-tank pressure-adjust valve,
107: high-pressure hydrogen gas-tank pressure-gage,
108: high-pressure chlorine gas-tank pressure-gage,
109: high-pressure hydrogen gas take-out adjust-valve,
110: high-pressure chlorine gas take-out adjust-valve,
117: seawater-pump inlet-valve,
118: seawater pump,
119: seawater-pump outlet check-valve,
120: seawater-pump outlet-valve,
121: seawater-pump inlet-pipe,
122: seawater-pump outlet-pipe
150: communication-adjust pipe,
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200: seawater electrolyzation unit,
300: solar thermal power generation unit.
