BACKGROUND
[0001] Some gaseous materials can be advantageously liquefied at low temperatures in order
to occupy less volume for better storage or transportation. Such liquefied gas may
be either transferred to be consumed, or pressurized and then turned from a liquid
phase back to a gaseous phase to be consumed. Such regasification process volume is,
for example, occurring in industrial ports, where liquefied natural gas (LNG) is turned
into compressed natural gas (CNG). Such regasification process consumes a significant
amount of energy. Such energy is for example used to heat liquefied gas in order to
evaporate it, as well as to run high power industrial pumps to transfer the gas through
the regasification installation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0002] Various example features will be apparent from the detailed description which follows,
taken in conjunction with the accompanying drawings, wherein:
Figure 1 is a schematic representation of an example system according to the present
disclosure.
Figures 2a-f are schematic representations of the example system of Figure 1.
Figure 3 is a schematic representation of another example system according to the
present disclosure.
Figure 4 is a schematic representation of a further example system according to the
present disclosure.
Figures 5a-e are schematic representations of the example system of Figure 4.
Figure 6 is a schematic representation of a further example system according to the
present disclosure.
Figure 7 is a schematic representation of a further example system according to the
present disclosure.
Figure 8 is a block diagram representation of an example regasification method according
to the present disclosure.
Figure 9 is a block diagram representation of an example method to cyclically modify
pressure according to the present disclosure.
DETAILED DESCRIPTION
[0003] The present disclosure aims at reducing or even at suppressing the energy costs of
pumping a fluid into a regasification or transfer installation to produce a high pressure
gas or pressurized liquefied gas downstream. In that case, while ambient temperature
may be used to evaporate a liquefied gas if the liquefied gas temperature is lower
than ambient, prior art systems are using high power pumps to evacuate the liquid
fluid. The present disclosure not only permits using ambient temperature to pressurize
liquefied gas, but also avoids the use of a pump through an elegant construction which
will be described in more detail below. In particular, example systems allow producing
a cycle between three equivalent containers and three types of fluids (compressed
liquid or gas, liquefied gas, and gas at lower pressure than compressed gas) such
that the energy stored in pressure and temperature of the fluids gets exchanged to
move the fluid between containers and run the cycle with a minimal energy cost.
[0004] As illustrated in Figure 1, this disclosure relates to a system for providing a compressed
gas or a compressed liquefied gas. In an example, compressed gas comprises a gaseous
phase and also comprises some gas in a liquid phase. In an example, more than 70%
of the compressed gas in mass is in a gaseous phase. In an example, less than 5% of
the compressed gas in mass is in a liquid phase. In an example, the compressed gas
is liquid in more than 99% of its mass. In an example, compressed gas is at a pressure
of between 6 and 10 bar. In an example, compressed gas is at a pressure of between
25 and 35 bar. In an example, compressed gas is at a pressure of at least 200 bar.
In an example, the compressed gas comprises natural gas. In an example, the compressed
gas comprises air. In an example, the compressed gas comprises N
2. In an example, the compressed gas comprises O
2. In an example, the compressed gas is at a temperature of between -90 and -60 degrees
Celsius. In an example, the compressed gas is at a temperature of between -60 and
-25 degrees Celsius.
[0005] The system of Figure 1 according to this disclosure comprises a supply connection
300 for the supply of liquefied gas. In an example, the liquefied gas comprises a
liquid phase and also comprises some gas in a gaseous phase. In an example, more than
70% of the liquefied gas in mass is in a liquid phase. In an example, less than 5%
of the liquefied gas in mass is in a gaseous phase. In an example, the liquefied gas
is in a liquid phase in more than 99% of its mass. In an example, liquefied gas is
at a pressure of between 1 and 2 bar. In an example, compressed gas is at a pressure
of between 2 and 4 bar. In an example, liquefied gas is at a pressure of at least
4 bar. In an example, the liquefied gas comprises natural gas. In an example, the
liquefied gas comprises cryogenic liquid natural gas. In an example, the liquefied
gas comprises air. In an example, the liquefied gas comprises N
2. In an example, the liquefied gas comprises O
2. In an example, the liquefied gas is at a temperature of between -180 and -140 degrees
Celsius. In an example, the liquefied gas is at a temperature of between -160 and
-80 degrees Celsius.
[0006] The system of Figure 1 according to this disclosure comprises three pressurized containers
101, 102 and 103. In an example, the pressurized containers are pressure vessels designed
to hold a fluid such as a gas, liquid or a combination of both at a pressure different
from the ambient pressure. In an example, the pressurized containers are made of steel.
In an example, the pressurized containers have a generally cylindrical enclosure.
In an example, a pressurized container has an inner volume of at least 0.3 cubic meters.
In an example, the three pressurized containers 101, 102 and 103 have an identical
structure. In an example, the three pressurized containers 101, 102 and 103 are located
at the same level, meaning at the same altitude, in order to minimize an impact of
gravity on a method to cyclically modify pressure according to this disclosure.
[0007] The system of Figure 1 according to this disclosure comprises an evaporator 210.
In an example the evaporator comprises radiating surfaces whereby liquefied gas passing
through the evaporator is exposed to ambient temperature or is heated by a heating
fluid through the radiating surfaces, thereby transmitting heat to the liquefied gas,
raising its temperature and progressively reducing its liquid phase, increasing its
gaseous phase, and increasing pressure inside the vessel or container as fluid passes
through the evaporator. In an example, the evaporator is a passive radiator using
ambient air as heat transfer fluid. In an example, the evaporator is a forced circulation
evaporator, using forced circulation from a heat transfer fluid to evaporate the liquefied
gas.
[0008] The system of Figure 1 according to this disclosure comprises a heat exchanger. The
heat exchanger is a counter current flow heat exchanger having two inputs and two
outputs; two inputs and a first output being connected to the pressurized containers
101, 102, 103, the second output being connected to a consumer connection 400. Using
a counter flow heat exchanger contributes to obtaining the energy savings aimed at
in the current disclosure by using the difference in temperature between the compressed
gas and the liquefied gas in the system of the disclosure in a beneficious manner
as will be explained below.
[0009] The system of Figure 1 according to this disclosure comprises a consumer connection
400. The consumer connection is in an example a connection to a compressed gas distribution
network. In an example, the consumer connection connects to a network distributing
compressed natural gas. The consumer connection 400 is connected to the heat exchanger.
In the system of this disclosure, a connection between elements is a pressurized connection
allowing a transfer of fluid (fluid including gas, liquid, or a mixture of gas and
liquid) between an element and another element, the connection being direct or indirect.
A direct connection can be provided by a tube between elements. A direct connection
can be provided by a tube mechanically connected to elements with seals maintaining
pressurization of the system. Elements include for example the supply connection,
the pressurized containers, the evaporator, the heat exchanger, valves or an expansion
element. An indirect connection can be provided between a first element and a second
element if one or more further elements is or are placed between the first and the
second element, meaning that a fluid moving between the first and the second element
would pass through the one or more further elements when moving from the first to
the second element or vice versa. In an example, the system comprises a pressurized
circuit between the elements of the system.
[0010] The system of Figure 1 according to this disclosure comprises valves interconnecting
each pressurized container 101, 102, 103 with the supply connection 300, with the
evaporator 210, and with the heat exchanger. In this example, valves 701, 702, 703
control the connection of respective containers 101, 102, 103 with a first fluid connection
of the evaporator 210 through an additional valve 710. Valves 707, 708 and 709 control
the connection of respective containers 101, 102 and 103 with a second fluid connection
of the evaporator 210. The evaporator 210 comprises an internal fluid circuit between
its first fluid connection and second fluid connection. Valves 704, 705 and 706 control
the connection of the respective containers 101, 102 and 103 through the respective
valves 707, 708 and 709 to the input of the current flow channel 501 of the heat exchanger.
Valve 714 controls the connection between the output of the current flow channel 501
of the heat exchanger to consumer connection 400. Valves 711, 712 and 713 control
the connection of respective containers 101, 102 and 103 to the input of counter current
flow channel 502 of the heat exchanger. Valve 700 controls the connection of supply
connection 300 to the rest of the system. Valves 715, 716 and 717 control the connection
of respective containers 101, 102 and 103 to the output of counter current flow channel
502 of the heat exchanger through an expansion element 600. As will be evidenced in
this description, this is only an example of connection between elements of the circuit,
and different circuits may be designed which will lead to a system according to this
disclosure.
[0011] The system of Figure 1 according to this disclosure comprises an expansion element
600. In an example, an expansion element reduces temperature in a fluid which flows
through the expansion element. In an example, a fluid entering the expansion element
has a higher proportion of gaseous phase than the fluid exiting the expansion element,
and the fluid entering the expansion element has a lower proportion of liquid phase
than the fluid exiting the expansion element. In an example, the expansion element
600 comprises a Joule-Thomson valve or a throttling element. The expansion element
600 is located between the first output of the counter current flow heat exchanger
and the pressurized containers. In an example, fluid flow through the expansion element
goes from the output of the counter current flow channel 502 towards one or more of
containers 101, 102 or 103.
[0012] In Figure 2a, the system of Figure 1 is represented in a specific state. In Figure
2a, container 101 is filled with liquefied gas. Container 101 is filled by opening
valves 701 and 700 between container 101 and supply connection 300 for the supply
of liquefied gas. In our Figures, open valves are represented by two opposing white
triangle, while closed valves are represented by two opposing black triangles. In
Figure 2a, container 101 gets filled by liquefied gas because the valves 700 and 701
are open and because pressure in container 101 is lower than pressure in the supply
connection 300. In an example, pressure in container 101 is of 6 bar and pressure
in the supply connection 300 is 7 bar. In figure 2a, liquefied gas is supplied to
a first pressurized container 101, the container being at a first pressure. In Figure
2a, container 102 is filled with gas in a gaseous phase at about 5 bar represented
by a light gray texture, and container 103 is filled with compressed gas at about
200 bar, represented by a dark gray texture. Containers 102 and 103 are in Figure
2 closed and without fluid connection to other elements due to valves being closed.
[0013] In Figure 2b, the system of Figure 1 is represented in a state directly following
the state represented in Figure 2a. In Figure 2b, valve 700 has been closed after
the filling of container 101 by liquefied gas through the supply connection 300. In
Figure 2b, both valves 710 and 707 have been opened, and valve 701 was maintained
opened, so that a circuit is open between container 101 and evaporator 210. When the
system is in this configuration, the first pressurized container 101 is connected
to evaporator 210 to evaporate liquefied gas to produce a first fluid and increase
pressure in the first pressurized container 101 to a second pressure. In an example,
the pressure in the container 101 raises from about 5 bar to about 200 bar during
this phase, whereby the liquefied gas progressively turns into compressed gas through
evaporation. In Figure 2b, we have illustrated a gaseous phase in container 101, the
gaseous phase being illustrated in a dark shade above the liquefied gas phase illustrated
by horizontal dashed lines. The remaining valves in the system remain closed. During
this phase, pressure raises in container 101 through evaporation in evaporator 210.
[0014] In Figure 2c, the system of Figure 1 is represented in a state directly following
the state represented in Figure 2b. In Figure 2c, valves 701, 707 and 710 remain open
as in Figure 2b, so that the liquefied gas continues to be submitted to evaporation.
In figure 2c, valves 704 and 714 are open so that the fluid present in container 101
exits at the second pressure for example of the order of 200 bar through consumer
connection 400. Indeed, the first container 101 is connected with consumer connection
400 via a channel 501 of a heat exchanger, the second pressure being higher than a
pressure in the consumer connection 400. In parallel to the flow from both container
101 and evaporator 210 towards the consumer connection through current flow channel
501 of the heat exchanger, a counter current flow takes place in counter current flow
channel 502. The counter current flow is produced by opening valves 713 and 716. Second
pressurized container 103 containing a second fluid, in this example compressed gas
at a pressure of about 200 bar in a gaseous phase, is connected to third pressurized
container 102, in this example originally filled with gas at a pressure of about 5
bar in a gaseous phase, such connection being via counter current flow channel 502
of the heat exchanger, the second fluid reducing its temperature as it flows through
the counter current flow channel, whereby in this example it exchanges heat with the
fluid passing through channel 501, the pressure in the second container 103 being
higher than the pressure in the third container 102, the second fluid passing through
expansion element 600 between the counter flow exchanger and the third pressurized
container 102.
[0015] In the example of Figure 2c, there is a first fluid circuit where a liquefied gas
at high pressure and low temperature raises in pressure as it flows through the heat
exchanger through channel 501. The resulting high pressure mixture of liquid and gas
is aimed at being distributed to consumers through the connection. In parallel, another
circuit through the counter current flow channel 502 and expansion element 600 turns
high pressure compressed gas in gaseous phase into a gas at a much lower pressure
and which may include a liquid phase. These two fluid circuits interact within the
heat exchanger, whereby on of the fluids raises its temperature and the other lowers
its temperature. The fluid flowing through the counter current flow channel 502 lowers
its temperature, the fluid flowing through the current flow channel 501 raises its
temperature. One should note that the terminology counter current flow channel and
current flow channel is relative and that both channels are equivalent but are containing
flows running in opposite directions.
[0016] In the example of Figure 2c, container 101 contains a fluid which has an increasing
gaseous compressed phase, and a decreasing liquefied gas phase. In parallel, pressure
in container 103 reduces, and the fluid contained in container 102 progressively contains
a higher liquefied gas phase, due to the compressed gas of container 103 lowering
its temperature in the heat exchanger and its pressure in the expansion element 600.
[0017] In Figure 2d, the system of Figure 1 is represented in a state directly following
the state represented in Figure 2c. The valves in Figure 2d are in the same position
as per Figure 2c. The change is illustrated by showing that container 101 has reached
a stage at which it is filled with high pressure compressed gas, for example about
200 bar, resulting from raising the liquefied gas in both temperature and pressure.
Container 102 now comprises a higher proportion of liquefied gas and remains at a
relatively low pressure of the order of 5 bar. Container 103 is also at low pressure,
for example containing gas at a pressure around 5 bar. The representation of the various
phases of fluid on the Figures are symbolic in that some of the phases may intermix
and have a variety of proportions.
[0018] In Figure 2e, the system of Figure 1 is represented in a state directly following
the state represented in Figure 2d. All valves have now been closed except valves
700 and 702 in order to progressively fill container 102 with liquefied gas, until
it reaches a level of filling as illustrated in Figure 2f. The filling may be complete
or may be partial. If one compares Figures 2f and 2a, one will see that the situations
are equivalent, but that the containers have now exchanged roles. One can illustrate
this change of roles in a cyclic manner in a table:
| Figure |
Content of Container 101 |
Content of Container 102 |
Content of Container 103 |
Comment |
| 2a |
Liquefied gas |
Low pressure gas |
Compressed gas |
Start of cycle 1 |
| 2f |
Compressed gas |
Liquefied gas |
Low pressure gas |
End of cycle 1 and start of following cycle 2 |
| Not illustrated |
Low pressure gas |
Compressed gas |
Liquefied gas |
End of cycle 2 and start of following cycle 3 |
| 2a |
Liquefied gas |
Low pressure gas |
Compressed gas |
End of cycle 3 and start of following cycle 4 |
[0019] As illustrated in the table, a cycle between containers allows providing compressed
gas from liquefied gas to a supply network without the need of a pump. While low power
fluid pumps may help run the cycle of this disclosure, in an example, the system is
a pumpless system.
[0020] . Numerous systems or circuits according to the disclosure may be designed. Another
example is illustrated in Figure 3. The system of Figure 3 comprises the elements
of the system of Figure 1 and further comprises a second evaporator 2002, the second
evaporator being connected to each of the pressurized containers 101, 102 and 103.
The system of Figure 3 permits an accelerated cycle. In an example both evaporators
210 and 220 are evaporating the fluid passing through them using ambient temperature.
When using ambient temperature, some evaporators can become covered in ice considering
the low temperature of liquefied gas, thereby reducing the evaporation process. For
example, adding another evaporator helps compensating such a reduction, for example.
One should note that the term evaporator in this disclosure can include a plurality
of evaporators. Evaporator 220 in the system of Figure 3 is connected to its own valve
720 allowing to selectively control use of evaporator 220.
[0021] A further example of a system according to the disclosure is illustrated in Figure
4, whereby the system comprises a first evaporator 231, second evaporator 232 and
third evaporator 233, being connected to each of the pressurized containers 101, 102
and 103, in this case respectively. Such plurality of evaporators can be considered
thermodynamically as one evaporator. Such a design includes valves 731, 732 and 733,
each corresponding to respective evaporators 231, 232 and 233. Such a design permits
using less valves than the system of Figure 1. It is indeed possible to implement
numerous various system according to this disclosure. The design of Figure 4 avoids
using an evaporator 231, 232 or 233 continuously, whereby the evaporator would be
connected to its respective container when such container is in a cycle of having
its content passing from liquefied gas to compressed gas, such that the respective
evaporator may not be used when the respective container is in a different part of
the cycle, for example when its content changes from low pressure gas to compressed
gas or when it is getting filled with liquefied gas. Such intermittent use of an evaporator
can allow such evaporator to raise its temperature to prepare for a new cycle, for
example if exposed to ambient conditions and submitted to freezing due to a low below
freezing temperature of a liquefied gas.
[0022] The system of Figure 4 is illustrated when functioning in figures 5a to 5e. In Figure
5a, container 101 is filled with liquefied gas by opening valves 701 and 700, thereby
connecting supply connection 300 with container 101. Container 102 is filled with
gas in gaseous phase at low pressure, for example 5 bar and Container 103 by compressed
gas at for example 200 bar. In Figure 5b, representing a state following in the cycle
the state of Figure 5a, all valves are closed except valve 731, thereby starting evaporation
of the content of container 101, raising pressure into container 101, reducing the
liquid phase in container 101. The state of the system of Figure 4 illustrated in
Figure 5b is followed by a state illustrated in Figure 5c, whereby the evaporator
231 continues to evaporate the content of container 101, whereby the higher pressure
content of container 101 goes through open valves 704, through the current flow channel
501 of a heat exchanger, through open valve 714 and to a consumer connection, providing
compressed gas at high pressure such as about 180000 hPa for example. In parallel,
valves 702 and 713 are open to allow a fluid flow between container 103 and container
102, whereby the compressed gas of container 103 lowers its temperature while flowing
through counter current flow channel 502 of the heat exchanger, lowering its pressure
while flowing through expansion element 600, and enter container 102 with lower pressure
and temperature, for example comprising a liquefied gas phase. Such flows of fluid
illustrated in Figure 5c lead to a state illustrated in Figure 5d, the valves in 5d
being in the same positions as in 5c, where the content of the containers is such
that container 103 contains gas at a lower pressure and container 101 compressed gas
at a higher pressure. 102 is at a lower pressure and lower temperature and may contain
some liquefied gas. In Figure 5e, illustrating a state following the state of Figure
5d, all valves are closed except valves 700 and 702 allowing filling of container
102 with liquefied gas in order to start a new cycle, container 102 now playing the
role played in the earlier cycle by container 101.
[0023] Another example of a system according to the invention is illustrated in Figure 6.
The system illustrated in Figure 6 comprises the elements of the system illustrated
in Figure 1, and the second output of the heat exchanger or the consumer connection
is connected to the gas phase of the containers, at the evaporator 210 output, via
a valve 740. Such connection permits injecting compressed gas into the containers,
thereby raising the temperature and pressure in the evaporator, for example to permit
resetting the circuit or system if the evaporator is saturated in its function and
does not evaporate with a satisfactory yield. Such connection could be considered
at other point of the circuit.
[0024] Another example of a system according to the invention is illustrated in Figure 7.
In Figure 7, a system is illustrated which comprises the elements of the system illustrated
in Figure 1 and further includes a supply tank 104 for the liquefied gas, the supply
tank 104 being connected to the three pressurized containers 101, 102 and 103. Supply
tank 104 may have been filled with liquefied gas coming from a liquefied gas transporting
ship for example. One should note that in the system illustrated in Figure 7 the supply
connection is a one way connection, meaning that there is no fluid flowing from the
system back into the supply tank. Avoiding such a return of fluid through a one way
connection avoids raising the temperature in the supply tank unnecessarily, and minimize
cavitation risk. In the system illustrated in Figure 7, the system further includes
an additional liquefied gas supply connection from the containers low output (low
output meaning a container output at the bottom of the containers, the bottom being
defined according to gravity) to an additional consumer connection 401 through a valve
750. Such additional consumer connection may be used to, for example, fill liquefied
gas transportation means such as a tanker truck. Not only would a system as per this
disclosure allow providing compressed gas from liquefied gas in a remote area or in
an area which does not benefit from a high power electrical connection for a high
power pump, but such an additional consumer connection would also allow providing
liquefied gas directly.
[0025] Figure 8 illustrates a regasification or pressurizing method according to the disclosure.
Such a method can be applied to any system according to the disclosure. In this example,
we are describing it applied to the system illustrated in Figure 1. Regasification
is the process of returning to a gaseous phase a gas which has been liquefied. The
method illustrated in Figure 8 comprises in step 801 supplying liquefied gas to a
first pressurized container such as 101, the pressurized container 101 being at a
first pressure. Step 802 illustrates connecting the first pressurized container 101
to evaporator 210 to evaporate liquefied gas to produce a first fluid and increase
pressure in the first pressurized container to a second pressure. Step 803 illustrates
connecting the first pressurized container 101 with consumer connection 400 via a
channel 501 of a heat exchanger, the first fluid raising its temperature as it flows
through the channel 501, the second pressure being higher than a pressure in the consumer
connection 400. Step 804 illustrates connecting a second pressurized container 103
containing a second fluid with a third pressurized container 102 via a counter current
flow channel 502 of the heat exchanger, the second fluid reducing its temperature
as it flows through the counter current flow channel 502, the pressure in the second
pressurized container 103 being higher than the pressure in the third pressurized
container 102, the second fluid passing through an expansion element 600 between the
counter flow exchanger and the third pressurized container 102. In an example, the
liquefied gas comprises cryogenic liquid natural gas and the first fluid comprises
compressed natural gas.
[0026] Figure 9 illustrates a method to cyclically modify pressure in a pressurized container
according to this disclosure. This method can be applied to any container described
in the present disclosure. We illustrate it here using the system illustrated in Figure
1. The method consists in repeating the following steps in a cycle providing in step
901 a one way supply 300 of liquefied gas in the pressurized container 101, the pressurized
container 101 being at a first pressure; evaporating in step 902 the liquefied gas
provided in the first pressurized container 101, raising the pressure in the pressurized
container 101 to a second pressure, the content of the first pressurized container
101 being evacuated from the pressurized container 101 towards a consumer connection
400 through a heat exchanger, the second pressure being higher than a consumer connection
pressure; lower in step 903 the pressure in the pressurized container 101 to a third
pressure by connecting the processing container 101 to an other pressurized container
103 through a counter current flow 502 of the heat exchanger and through an expansion
element 600, the other processing container 103 containing a low pressure fluid, the
low pressure fluid having a low pressure of less than the first pressure, the expansion
element 600 being located between the heat exchanger and the other pressurized container
103. In this example, steps 901, 902 and 903 are repeated in cycle. In an example,
the steps are implemented by opening and closing valves, the valves introducing losses
of pressure. In another example, the steps are implemented by using a pump in addition
to valves. In an example, the pressurized container 101 is filled with liquefied gas
providing a one way supply of liquefied gas in the pressurized container 101, thereby
avoiding returning fluid into a supply tank or supply network. In an example, the
first pressure is of less than 6 bar and the consumer connection pressure is of more
than 200 bar.
[0027] The valves may be operated manually or through a control system, which may comprise
electro-mechanical elements or electronic elements. Control may take place with a
controller, the controller comprising a processor and data storage, the data storage
comprising a machine readable instruction set to operate the valves according to this
disclosure.
[0028] The preceding description has been presented to illustrate and describe certain examples.
Different sets of examples have been described; these may be applied individually
or in combination, sometimes with a synergetic effect. This description is not intended
to be exhaustive or to limit these principles to any precise form disclosed. Many
modifications and variations are possible in light of the above teaching. It is to
be understood that any feature described in relation to any one example may be used
alone, or in combination with other features described, and may also be used in combination
with any features of any other of the examples, or any combination of any other of
the examples.
1. A system for providing a pressurized liquefied gas or compressed gas, the system comprising:
a supply connection (300) for the supply of liquefied gas;
three pressurized containers (101, 102, 103), an evaporator (210) and a heat exchanger;
a consumer connection (400) connected to the heat exchanger;
valves interconnecting the pressurized container (101, 102, 103) with the supply connection
(300), with the evaporator (210), and with the heat exchanger;
an expansion element (600), and
the heat exchanger is a counter current flow heat exchanger having two inputs and
two outputs, two inputs and a first output being connected to the pressurized containers
(101, 102, 103), the expansion element being located between the first output and
the pressurized containers, the second output being connected to the consumer connection.
2. The system of claim 1, further comprising a second evaporator (220), the second evaporator
(220) being connected to each of the pressurized containers (101, 102, 103).
3. The system of claim 1, comprising a second (232) and a third (233) evaporator, each
evaporator (231, 232, 233) being connected to a respective pressurized container (101,
102, 103).
4. The system of claim 1, whereby the evaporator (210) is connected to the second output
of the heat exchanger via a valve.
5. The system of any of the above claims, whereby the expansion element (600) comprises
a Joule-Thomson valve.
6. The system of any of the above claims, including an additional liquefied gas supply
connection to an additional consumer connection (401).
7. The system of any of the above claims, whereby the supply connection (300) is a one
way connection.
8. The system of any of the above claims, whereby the system is a pumpless system.
9. A pressurizing method, the method comprising:
supplying liquefied gas to a first pressurized container (101) the pressurized container
(101) being at a first pressure,
connect the first pressurized container (101) to an evaporator (210) to evaporate
liquefied gas to produce a first fluid and increase pressure in the first pressurized
container (101) to a second pressure,
connect the first pressurized container (101) with a consumer connection (400) via
a channel (501) of a heat exchanger, the first fluid raising its temperature as it
flows through the channel (501), the second pressure being higher than a pressure
in the consumer connection (400),
connect a second pressurized container (103) containing a second fluid with a third
pressurized container (102) via a counter current flow channel (502) of the heat exchanger,
the second fluid reducing its temperature as it flows through the counter current
flow channel (502), the pressure in the second pressurized container (103) being higher
than the pressure in the third pressurized container (102), the second fluid passing
through an expansion element (600) between the counter flow exchanger and the third
pressurized container (102).
10. A pressurizing method according to claim 9, whereby the liquefied gas comprises cryogenic
liquid natural gas and the first fluid comprises either pressurized liquefied natural
gas or compressed natural gas.
11. A method to cyclically modify pressure in a pressurized container (101), the method
comprising repeating the following steps in a cycle:
providing a one way supply (300) of liquefied gas in the pressurized container (101),
the pressurized container (101) being at a first pressure;
evaporating the liquefied gas provided in the first pressurized container (101), raising
the pressure in the pressurized container (101) to a second pressure, the content
of the first pressurized container (101) being evacuated from the pressurized container
(101) towards a consumer connection (400) through a heat exchanger, the second pressure
being higher than a consumer connection pressure;
lower the pressure in the pressurized container (101) to a third pressure by connecting
the processing container (101) to an other pressurized container (103) through a counter
current flow (502) of the heat exchanger and through an expansion element (600), the
other processing container (103) containing a low pressure fluid, the low pressure
fluid having a low pressure of less than the first pressure, the expansion element
(600) being located between the heat exchanger and the other pressurized container
(103).
12. The method of claim 11, whereby the steps are implemented by opening and closing valves,
the valves introducing losses of pressure.
13. The method according to any of claims 11 or 12, whereby the pressurized container
(101) is filled with liquefied gas providing a one way supply of liquefied gas in
the pressurized container.
14. The method according to any of claims 11 to 13, whereby the first pressure is of less
than 6 bar
15. The method according to any of claims 11 to 14, whereby the second pressure is of
more than 200 bar.