Circuit for re-liquefying fluid and supplying re-liquefied fluid to consumption unit

Abstract

To execute control to prevent the pressure in the highest part of a tank from damaging the tank relating to a field of a vessel using, storing, and / or conveying liquefied natural gas and / or liquefied petroleum gas.SOLUTION: The present invention is related to a circuit (1) in which first fluid (4) stored in a first tank (2) and second fluid (8) stored in a second tank (6) flow. The circuit (1) includes at least one management pipe (20) for managing the state of the second fluid (8) intended for the second fluid (8) taken in a liquid state from the second tank (6) to pass and flow through. The circuit (1) includes a supply pipe (15) extending from a second pipe (16) to a consumption device (17) for supplying the first fluid (4) to the consumption device (17) that uses it as a fuel. The supply pipe (15) is configured so that the first fluid (4) in a liquid state passes and flows through it, and the supply pipe (15) includes at least one pump element (19) for increasing the pressure of the first fluid (4) in the supply pipe (15).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the field of ships using, storing and / or transporting liquefied natural gas and / or liquefied petroleum gas, and more particularly to the field of systems for managing the condition of the liquefied natural gas and / or liquefied petroleum gas transported on such ships. [Background technology]

[0002] Such a vessel conventionally comprises tanks for storing natural gas in liquid state and / or petroleum gas in liquid state. Such a vessel may, for example, comprise a first tank for storing liquid natural gas and a second tank for storing liquid petroleum gas. However, such a vessel may transport a first petroleum gas contained in the first tank and a second petroleum gas contained in the second tank, the first petroleum gas being different from the second petroleum gas, for example in its composition. That is, such a vessel may transport a first fluid, which may be liquefied natural gas or liquefied petroleum gas, and a second fluid, which is different from the first fluid and may be liquefied natural gas or liquefied petroleum gas.

[0003] Natural gas is a liquid at temperatures below -160°C at atmospheric pressure, for example. Such tanks are never completely thermally insulated, which means that at least some of the natural gas will evaporate within the tank. Thus, such tanks contain both liquid and gaseous natural gas, with the gaseous natural gas, also known as "BOG" or "boil off gas", accumulating at the top of the tank. The pressure at the top of this tank needs to be controlled to avoid damaging the tank.

[0004] Petroleum gas has a boiling point at atmospheric pressure generally between 0°C and 50°C depending on its composition. Petroleum gas also tends to at least partially evaporate when stored in tanks, and the pressure at the top of the tank created by the evaporated petroleum gas must also be controlled so as not to damage the tank.

[0005] Typically, such vessels comprise several systems for managing the state of the first and second fluids in order to limit the evaporation of each of these fluids at the top of the tank. Such management systems are therefore arranged, on the one hand, to liquefy the first fluid and, on the other hand, to liquefy the second fluid independently of the liquefaction of the first fluid. Furthermore, the systems for managing one of the fluids generally include compression elements for compressing the evaporated first and / or second fluid, by means of which the pressure of said fluids can be increased. As a result, this type of management system is generally of considerable size and takes up a considerable amount of space, either on the vessel or around the dock. Furthermore, they are not suitable for supplying one of the fluids to a consumer device that uses one of the fluids as fuel. Summary of the Invention

[0006] The present invention aims to reduce the volume occupied by the management system and the space taken up by the compression elements for managing the state of the two fluids while supplying the first and / or second fluid to a consumer device that uses them as fuel. More specifically, the present invention proposes a system for managing the state of the evaporated first fluid, which also makes it possible to cool the second fluid in liquid state, thereby reducing the amount of evaporated second fluid while sending part of the first fluid in liquid state to the consumer device as fuel.

[0007] The invention mainly relates to a circuit through which a first fluid contained in a first tank and a second fluid contained in a second tank can flow, the first fluid having a boiling point lower than the boiling point of the second fluid, the circuit comprising at least a first pipe extending from the first tank to a heat exchange element, the first fluid taken from the first tank in a gaseous state is intended to flow through the first pipe, the heat exchange element being configured to condense the first fluid, the circuit comprising a second pipe extending from the heat exchange element to the first tank, the first fluid in a liquid state and / or in a two-phase state is intended to flow through the second pipe. the circuit includes at least one management pipe for managing the state of the second fluid, through which the second fluid taken in a liquid state from the second tank is intended to flow, the circuit includes a supply pipe extending from the second pipe to a consumer device for supplying at least the first fluid as fuel to the consumer device, the supply pipe being configured for at least the first fluid in a liquid state to flow through, the supply pipe including at least one pump element for increasing the pressure of the first fluid in the supply pipe.

[0008] It should be noted that the circuit controls, on the one hand, at least the pressure and temperature, and more generally the state, of a first fluid contained in a first tank and a second fluid contained in a second tank, and, on the other hand, supplies at least the first fluid as fuel to a consumer unit, which can for example be a propulsion engine or an auxiliary engine on board the ship in which the circuit according to the invention and the first and second tanks are installed.

[0009] The pump element in particular makes it possible to increase the pressure of at least a first fluid, which flows in liquid state through a supply line to a consumer unit. The invention makes use of the fact that the pressure of the first fluid is high when it passes through the first line, this high pressure being used, on the one hand, to liquefy the first fluid and thus to manage the pressure in the first tank and accordingly in the second tank, and, on the other hand, to supply the consumer. The pressure required to supply the consumer is therefore a combination of the pressure prevailing in the first line and the pressure provided by the pump element. This clever combination makes it possible to use pump elements that are less complex, cheaper and more reliable.

[0010] Furthermore, using the first fluid as fuel has the advantage of reducing the consumption of energy required for the thermal management of the first fluid contained in the first tank, which can mean an energy saving of up to 30% compared to a circuit that does not include such piping supplying the consumer.

[0011] The first and second fluids are, for example, petroleum gas stored in a tank in a liquid state, the first fluid being, for example, a mixture of 92% propane and 8% butane having a boiling point of -47°C at atmospheric pressure, i.e. the first fluid is liquid when its temperature is below -47°C at atmospheric pressure, and the second fluid is, for example, approximately 100% butane and has a boiling point of 0°C at atmospheric pressure, i.e. the second fluid is liquid when its temperature is below 0°C at atmospheric pressure.

[0012] According to another embodiment of the invention, the first fluid is natural gas, for example mostly methane, having a boiling point of about -160°C at atmospheric pressure.

[0013] According to another embodiment of the invention, the first fluid may for example consist of 100% ethane and have an evaporation temperature of -89°C, and the second fluid may consist of liquefied petroleum gas containing a mixture of 92% propane and 8% butane and have an evaporation temperature of -47°C.

[0014] According to another embodiment of the invention, the first fluid consists, for example, of 100% ethane and has an evaporation temperature of -89°C, and the second fluid consists of 100% ammonia with an evaporation temperature of -33°C.

[0015] According to another embodiment of the invention, the first fluid consists, for example, of 100% propane and has an evaporation temperature of -42°C, and the second fluid consists of 100% ammonia with an evaporation temperature of -33°C.

[0016] The above temperatures are measured at atmospheric pressure.

[0017] Furthermore, "the supply tube is configured to allow at least a first fluid in a liquid state to flow therethrough" means that in a first embodiment of the invention, only the first fluid flows through the supply tube, or in a second embodiment of the invention, means that the first fluid and at least one further fluid, e.g. the second fluid, flows through the supply tube.

[0018] According to another optional feature of the invention, the circuit comprises at least one cooling pipe intended for the flow of the first fluid extending from the second pipe to the first pipe, the first pipe comprising at least a first compression element and a second compression element, the cooling pipe being connected to the first pipe between the first compression element and the second compression element.

[0019] According to another optional feature of the invention, the circuit comprises at least one cooling unit for cooling a second fluid in a liquid state flowing through a management pipe for managing the state of the second fluid, the cold air generated by the cooling unit being produced by evaporation (boil-off) of the first fluid flowing through at least one cooling pipe extending from the second pipe to the first pipe and intended for the first fluid to flow through.

[0020] The second fluid flowing through the management piping is cooled by the cooling unit, such that the temperature of the second fluid flowing through the management piping downstream of the cooling unit is lower than the temperature of the first fluid flowing through the cooling piping downstream of the cooling unit, which has the effect of lowering the temperature of the second fluid contained in the second tank, thereby limiting evaporation of the second fluid present in the second tank.

[0021] The cold used to reduce the temperature of the second fluid flowing through the management pipe is produced by evaporation of a portion of the first fluid flowing through the cooling pipe, more precisely, this portion of the first fluid is expanded, i.e. the pressure of this portion of the first fluid is reduced, so that the temperature of the second fluid is reduced by heat exchange between the first and second fluids.

[0022] According to another optional feature of the invention, the cooling unit includes at least a heat exchanger and an expansion element, the heat exchanger exchanging thermal energy between a first fluid flowing through the cooling pipes and a second fluid flowing through the management piping.

[0023] More specifically, a first fluid flowing through the cooling pipe is expanded by an expansion element before flowing through the heat exchanger. As the second fluid flowing through the management pipe passes through the heat exchanger, it gives up thermal energy to the expanded first fluid flowing through the cooling pipe also passing through the heat exchanger. Thus, downstream of the cooling unit, the second fluid flowing through the management pipe is cooled to a temperature close to that of the first fluid flowing through the cooling pipe.

[0024] In other words, the first fluid flowing through the cooling pipe and passing through the heat exchanger is heated and evaporated in the heat exchanger by acquiring thermal energy from the second fluid flowing through the management pipe, and the heated and evaporated first fluid is then sucked into one of the compression elements attached to the first pipe.

[0025] Furthermore, it is inside the heat exchanger that the temperature of the second fluid flowing through the management pipe decreases, specifically, due to the transfer of thermal energy from the second fluid flowing through the management pipe to the first fluid flowing through the cooling pipe, and it approaches the temperature of the first fluid flowing through the cooling pipe. It should be noted that the temperature of the second fluid flowing through the management pipe decreases during the exchange of thermal energy that takes place in the heat exchanger.

[0026] According to another optional feature of the invention, the heat exchanger includes at least a first passageway constituting a cooling pipe and a second passageway constituting a management pipe, and an expansion element is disposed between the first passageway and the second pipeway.

[0027] It should be noted that in this configuration, the first fluid flowing through the cooling tube is expanded by the expansion element before the first fluid flows through the first passage of the heat exchanger.

[0028] According to another optional feature of the invention, the circuit includes at least one pipe extending from the second piping to the first piping through which the first fluid flows, the circuit including at least one chiller for cooling the first fluid flowing in the second piping, the cold generated by the chiller resulting from evaporation of the first fluid flowing in the pipe.

[0029] The first fluid flowing through the second pipe is cooled by the cooling device, and the temperature of the first fluid flowing through the second pipe downstream of the cooling device is lower than the temperature of the first fluid flowing through the pipe downstream of the cooling device.

[0030] The cold air used to reduce the temperature of the first fluid flowing in the second pipe is produced by evaporation of a portion of the first fluid flowing in the pipe, more precisely, this portion of the first fluid is expanded, i.e. its pressure is reduced, so that it reduces the temperature of the first fluid flowing in the second pipe.

[0031] According to another optional feature of the invention, the supply pipe is connected to the second pipe at a split point located on the second pipe between the heat exchange element and the cooling device, i.e. the split point between the second pipe and the supply pipe is located upstream of the cooling device and downstream of the heat exchange element.

[0032] According to another optional feature of the invention, the circuit comprises at least one phase separation element for the first fluid arranged on the second piping, the first fluid flows from said phase separation element through the second piping to the first tank, and the circuit comprises a gas pipe extending from said phase separation element to the second piping. It should be noted that the split point is arranged in a part of the second piping downstream of the phase separation element.

[0033] According to another optional feature of the invention, the supply pipe is connected to the second pipe at a split point located on the second pipe between the phase separation element and the cooling device, such that the first fluid flowing through the supply pipe results from accumulation of the first fluid in a liquid state in the phase separation element.

[0034] According to another optional feature of the invention, a supply pipe extends from the cooling pipe to the consumer device, and a branch point of the supply pipe and the cooling pipe is located between the cooling device and the cooling unit. It should be noted that the first fluid is cooled by the cooling device before flowing through the supply pipe.

[0035] According to another optional feature of the invention, a supply pipe extends from the cooling pipe to the consumer, the junction of the supply pipe and the cooling pipe being located between the expansion element of the cooling unit and the cooling device.

[0036] According to another optional feature of the invention, the circuit includes a control valve for controlling the flow rate of the first fluid through the supply conduit, i.e. the control valve is mounted in the supply conduit upstream of the pump element.

[0037] According to another optional feature of the invention, the circuit includes a transfer pipe extending between the management pipe and the supply pipe, such that the transfer pipe fluidly connects the management pipe to the supply pipe. [Brief description of the drawings]

[0038] Further features, details and advantages of the invention will become more apparent on the one hand from reading the description which follows and on the other hand from some embodiments thereof, given by way of non-limiting example with reference to the attached drawings, in which:

[0039] [Figure 1] 1 is a schematic diagram showing a circuit according to a first embodiment. [Diagram 2] 5 is a schematic diagram showing a circuit according to a second embodiment. [Diagram 3] 13 is a schematic diagram showing a circuit according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] The features, variants, and different embodiments of the invention may be related to each other in various combinations, unless they are inconsistent or mutually exclusive. In particular, variants of the invention that include only one selected from the features described below, apart from the other features described, may be envisaged, provided that this selected feature provides a technical advantage and / or is sufficient to differentiate the invention from the prior art.

[0041] Furthermore, the terms "upstream" and "downstream" as used in the following description refer to the direction of circulation of a first fluid and / or a second fluid in a circuit through which the first and second fluids can flow.

[0042] 1 shows a circuit 1 including at least a first fluid 4 and a second fluid 8, a first tank 2 containing the first fluid 4, and a second tank 6 containing the second fluid 8. The first tank 2, the second tank 6, and / or the circuit 1 may be installed, for example, on a ship transporting the first fluid 4 and the second fluid 8.

[0043] The first fluid 4 has a boiling point lower than the boiling point of the second fluid 8, and the two temperatures are measured at the same pressure. The first fluid 4 is a natural gas, such as methane, having a boiling point of about -160°C, i.e., the first fluid 4 is liquid when at a temperature below -160°C at atmospheric pressure. The second fluid 8 is a petroleum gas, such as propane, butane, or a mixture of propane and butane, having a boiling point between 0°C and -51°C at atmospheric pressure. However, the first fluid 4 can also be a petroleum gas, such as propane, butane, or a mixture of propane and butane, as long as the first fluid 4 has a boiling point lower than the boiling point of the second fluid 8.

[0044] According to the example given herein, the first fluid 4 and the second fluid 8 are petroleum gas, the first fluid 4 being, for example, a mixture consisting of about 92% propane and about 8% butane and having a boiling point of −47° C. at atmospheric pressure, and the second fluid 8 being, for example, consisting of about 100% butane and having a boiling point of 0° C. at atmospheric pressure.

[0045] According to a first alternative embodiment of the invention, the first fluid 4 is ethane and has a boiling point of -89°C and the second fluid 8 is a liquefied petroleum gas containing a mixture of propane and butane and has a boiling point of -47°C.

[0046] According to a second alternative of the invention, the first fluid 4 is ethane and has an evaporation temperature of -89°C and the second fluid 8 is ammonia and has a boiling point of -33°C.

[0047] According to a third alternative of the invention, the first fluid 4 is propane and has a boiling point of -42°C and the second fluid 8 is ammonia and has a boiling point of -33°C.

[0048] The first tank 2 and the second tank 6 are designed to store a first fluid 4 and a second fluid 8 in liquid form at temperatures below their respective boiling points at atmospheric pressure. To this end, the tanks 2 and 6 each comprise at least a sealing membrane in contact with one of the fluids and an insulating barrier surrounding the sealing membrane and helping to keep one of the fluids below its boiling point.

[0049] Advantageously, each of the tanks 2, 6 has a primary layer consisting of a primary sealing membrane in contact with one of the fluids and a primary insulating barrier surrounding the primary sealing membrane, and a secondary layer consisting of a secondary sealing membrane surrounding the primary layer and in contact with the primary insulating barrier and a secondary insulating barrier surrounding the secondary sealing membrane.

[0050] The first fluid 4 is stored in the first tank 2 mainly in liquid form under atmospheric pressure. However, a portion of the first fluid 4 evaporates to form a cover at the top 10 of the first tank 2, and therefore the first fluid 4 exists in gaseous form at the top 10.

[0051] Similarly, the second fluid 8 is stored in the second tank 6 mainly in liquid form at atmospheric pressure. However, some of the second fluid 8 evaporates and forms a blanket at the top 11 of the second tank 6, so that at the top 11 the second fluid 8 is present in gaseous form.

[0052] The circuit 1 is configured to reliquefy at least a portion of the gaseous first fluid 4 present in the top 10 of the first tank 2 and to supply the first fluid 4 to a consumer device that uses the first fluid 4 as fuel. To this end, the circuit 1 comprises at least a first pipe 12 through which the first fluid 4 flows from the first tank 2 to a plurality of compression elements 14, and a second pipe 16 extending from the first pipe 12 to the first tank 2, through which the first fluid 4 flows in liquid and / or two-phase state from the first pipe 12 to the first tank 2. Furthermore, the circuit 1 comprises a cooling pipe 18 extending from the second pipe 16 to the first pipe 12, through which the first fluid 4 flows from the second pipe 16 to the first pipe 12.

[0053] According to the invention, the circuit 1 comprises a supply line 15 for supplying a first fluid to a consumer 17 for use as fuel, said supply line 15 extending from a second line 16 to the consumer 17, through which the first fluid 4 in liquid state flows and which comprises at least one pump element 19 for increasing the pressure of the first fluid 4 in the supply line 15. It is to be noted that a part of the first fluid 4 flowing in the second line 16 is intended to flow through the supply line 15 in order to be used as fuel for the consumer 17. Furthermore, the first fluid 4 flowing through the supply line is in liquid state and the pump element 19 increases the pressure of the first fluid 4 flowing in the supply line 15 to the consumer 17.

[0054] A more detailed description of the supply pipe 15 will be provided further below, and more particularly after the first pipe 12 , the second pipe 16 , the cooling unit 24 , the cooling pipe 18 , and the management pipe 20 .

[0055] Moreover, the circuit 1 further comprises at least one management pipe 20 for managing the state of the second fluid, through which at least a part of the second fluid 8 flows from the second tank 6 to a liquid outlet 22 for the second fluid 8 of the second tank 6. In particular, the liquid outlet 22 makes it possible to spray the cooled second fluid 8 into the second tank 6, in particular to cool the second fluid 8 present in the top 11 of the second tank 6. Reducing the temperature of the second fluid 8 present in the top 11 of the second tank 6 makes it possible to reduce the pressure exerted by the evaporated second fluid 8 present in said top 11 of the second tank 6. According to the embodiment shown here in FIG. 1, the liquid outlet 22 takes the form of a spray bar facilitating the distribution of the second fluid 8 sprayed in the top 11 of the second tank 6.

[0056] The management system 1 includes a cooling unit 24 which cools the second fluid 8 in liquid state flowing through the management piping 20, the cold generated by the cooling unit 24 being the result of the evaporation of the first fluid 4 flowing through the cooling tube 18. It should be noted here that the first fluid 4 is at a sufficiently low temperature that it flows through the cooling tube 18 and the cooling unit 24 to cool the second fluid 8 flowing through the management piping 20. In this case, the second fluid 8 gives up thermal energy to the first fluid 4.

[0057] A more detailed description of the second piping 16, the cooling unit 24, the cooling pipes 18, the control pipes 20 and the supply pipes 15 of the circuit 1 is provided following the description of the first piping 12 below, with particular reference to FIG.

[0058] The first pipe 12 extends from inside the first tank 2, and more specifically includes a gas inlet 26 that opens into the top 10 of the first tank 2, where the first fluid 4 in gas phase is present. Therefore, the first fluid 4 in gaseous state present in the top 10 of the first tank 2 comes into direct contact with the gas inlet 26 of the first pipe 12, and as a result, the first fluid 4 in gaseous state can be sucked by the multiple compression elements 14.

[0059] The first fluid 4 in gaseous state moves from the top 10 of the first tank 2 through the first pipe 12 to the multiple compression elements 14 under the effect of suction created by the multiple compression elements 14. More specifically, the multiple compression elements 14 are configured to increase the pressure of the first fluid 4 in gaseous state before it is sent to a consumer device.

[0060] 1, the plurality of compression elements 14 includes a first compression element 14a, a second compression element 14b, and a third compression element 14c, which are arranged on the first pipe 12 in this order in the direction of circulation of the first fluid 4 in said first pipe. The plurality of compression elements 14 serve to define a first portion 28 of the first pipe 12 extending between the gas inlet 26 and the first compression element 14a, a second portion 30 of the first pipe 12 extending between the first compression element 14a and the second compression element 14b, a third portion 32 of the first pipe 12 extending between the second compression element 14b and the third compression element 14c, and a fourth portion 34 of the first pipe 12 extending between the third compression element 14c and the second pipe 16.

[0061] The pressure of the first fluid 4 in gaseous state increases as it flows through the first pipe 12 through the multiple compression elements 14, with the first fluid 4 being at atmospheric pressure in the first portion 28 and reaching a pressure of approximately 24 bar in the fourth portion 34.

[0062] 1 , the coolant circulation system 36 includes at least one heat exchange element 38 for heat exchange between the coolant flowing through the circulation system 36 and the first fluid 4 in gaseous state flowing through the first pipe 12. This heat exchange element 38 separates the first pipe 12 from the second pipe 16. More specifically, the heat exchange element 38 is arranged downstream of the fourth portion 34 of the first pipe 12.

[0063] The heat exchange element 38 exchanges thermal energy between the cooling fluid and the first fluid 4. The cooling fluid may be a heat transfer fluid and / or water, and the circulation system 36 may be installed, for example, on a marine vessel and connected directly to the body of water in which the vessel is navigating.

[0064] Advantageously, the circulation system 36 comprises a first heat exchange element 40 attached to the second section 30 of the first pipe 12, a second heat exchange element 42 attached to the third section 32 of the first pipe 12 and a third heat exchange element 38 attached to the fourth section 34 of the first pipe 12, each of the heat exchange elements 38, 40, 42 exchanging thermal energy between the first fluid 4 in gaseous state flowing through the first pipe 12 and a cooling liquid. It should be noted that alternating the compression elements 14 and the heat exchange elements 38, 40, 42 arranged along the first pipe 12 allows to reduce the temperature of the first fluid 4 after each stage of compression performed by the compression elements.

[0065] In the example shown in Fig. 1 here, when the first fluid 4 passes through the multiple compression elements 14, the pressure and temperature of the fluid increases. To prevent this temperature from becoming too high, the first fluid 4 exchanges thermal energy with a coolant using the first, second and third heat exchange elements 40, 42, 38. For example, the temperature of the first fluid 4 flowing through the second portion 30 downstream of the first heat exchange element 40 is about 7°C, the temperature of the first fluid 4 flowing through the third portion 32 downstream of the second heat exchange element 42 is about 40°C, and the temperature of the first fluid 4 flowing through the fourth portion 34 downstream of the third heat exchange element 38 is above 43°C.

[0066] Furthermore, the boiling point of the fluid also changes depending on the pressure to which it is subjected. The first fluid 4, which may be, for example, a mixture of about 92% propane and about 8% butane, has a boiling point of about 43° C. when subjected to a pressure of about 24 bar. The first fluid 4 is therefore in a gaseous state in the fourth portion 34 upstream of the third heat exchange element 38, and passes through the third heat exchange element 38 into a liquid or two-phase state by exchanging thermal energy with the cooling liquid, and flows in a liquid or two-phase state in the second pipe 16 downstream of the third heat exchange element 38. The first fluid 4 therefore flows in a liquid or two-phase state in the second pipe 16 downstream of the third heat exchange element 38.

[0067] Furthermore, "two-phase state" refers to a state in which a portion of the first fluid 4 is in a liquid state and another portion of the first fluid 4 is in a gaseous state.

[0068] Before describing the cooling unit 24, the cooling pipe 18, the management pipe 20 and the supply pipe 15 in more detail, the second pipe 16 of the circuit 1 will now be described in more detail, with particular reference to FIG.

[0069] The first fluid 4 flows from the first pipe 12 through the second pipe 16 , more particularly from the third heat exchange element 38 , to the first tank 2 .

[0070] 1, the management system 1 includes a phase separation device 44 for the first fluid 4 arranged on the second pipe 16. The phase separation device 44 is configured to separate multiple phases present in the first fluid 4 flowing through the second pipe 16. That is, the phase separation device 44 is configured to separate the first fluid 4 in a liquid state from the first fluid 4 in a gaseous state. Then, the first fluid 4 in a liquid state separated in the phase separation device 44 flows to the second pipe 16.

[0071] The circuit 1 includes a gas line 46 through which the first fluid 4 flows from the phase separation device 44 to the second line 16 .

[0072] 1, the management system 1 includes at least one pipe 48 connecting the first piping 12 with the second piping 16 and through which the first fluid 4 flows from the second piping 16 to the first piping 12. The management system 1 includes at least one cooling device 50 for cooling the first fluid 4 flowing through the second piping 16, the cold generated by the cooling device 50 being generated by evaporation of the first fluid 4 flowing through the pipe 48.

[0073] An intersection 52 is formed between the pipe 48 and the second piping 16, at which the first fluid 4 can flow either through the second piping 16 to the first tank 2 or through the pipe 48 to the first piping 12, and the cooling device 50 is configured such that the temperature of the first fluid 4 flowing through the second piping 16 is reduced by evaporation of the first fluid 4 flowing through the pipe 48.

[0074] 1, the gas pipe 46 is connected to the second pipe 16 downstream of the intersection 52 between the second pipe 16 and the pipe 48. The first fluid 4 in a gaseous state flowing through the gas pipe 46 mixes with the first fluid 4 in a liquid state flowing through the second pipe 16 downstream of the intersection 52, so that the first fluid 4 is in a two-phase state in the second pipe 16 between the intersection 52 and the cooling device 50.

[0075] More specifically, the cooling system 50 includes at least a heat exchanger 54 and an expansion device 56, the heat exchanger 54 including a first passage 58 that constitutes the second piping 16 and a second passage 60 that constitutes the pipe 48, the expansion device 56 being disposed on the pipe 48 upstream of the second passage 60. The heat exchanger 54 is configured to exchange heat between the first fluid 4 flowing through the second piping 16 and the first fluid 4 flowing through the pipe 48.

[0076] Configured in this manner, the heat exchanger 54 exchanges thermal energy between the first fluid 4 flowing in the second piping 16 and the first fluid 4 flowing in the pipe 48, and the exchange of thermal energy between the first fluid 4 flowing in the second piping 16 and the first fluid 4 flowing in the pipe 48 is specifically performed in the first passage 58 and the second passage 60 of the heat exchanger 54. Due to the thermal energy exchanged between the first fluid 4 flowing in the second piping 16 and the first fluid 4 flowing in the pipe 48, the temperature of the first fluid 4 flowing in the second piping 16 is lowered, and the first fluid 4 flowing in the second piping 16 transfers the thermal energy to the first fluid 4 flowing in the pipe 48.

[0077] This transfer of thermal energy is accomplished by virtue of the presence of an expansion device 56 which reduces the pressure of the first fluid 4 flowing through the pipe 48, facilitating its change of state.

[0078] The temperature drop between the first fluid 4 flowing upstream of the first passage 58 of the second pipe 16 and the first fluid 4 flowing downstream of the first passage 58 of the second pipe 16 is at least 20° C. Advantageously, this temperature difference is between 25° C. and 35° C.

[0079] The reduction in temperature of the first fluid 4 flowing in the second pipe 16 causes the first fluid 4 to change from a two-phase state to a liquid state. The first fluid 4 flowing in the second pipe 16 downstream of the first passage 58 of the heat exchanger 54 is therefore in a liquid state and has, for example, a temperature of about 14° C. and a pressure of about 24 bar.

[0080] 1, the expansion element 56 of the cooling device 50 is attached to the pipe 48 upstream of the second passage 60. In other words, it should be noted that the first fluid 4 in a liquid state, which is fed to the second passage 60, expands before reaching the second passage 60, i.e. the pressure is reduced and the state of the first fluid 4 changes, so that it passes from a two-phase state to a gaseous state within the second passage 60. For example, the first fluid 4 may be expanded to a pressure of about 3 bar, so that the first fluid 4 changes from a pressure of about 24 bar upstream of the expansion element 56 to a pressure of 3 bar between the expansion element 56 and the first piping 12.

[0081] Due to the pressure difference, and the resulting temperature difference, between the first fluid 4 in a gaseous state flowing through the second passage 60 and the first fluid 4 in a liquid state or two-phase state flowing through the first passage 58, the first fluid 4 in a liquid state or two-phase state flowing through the first passage 58 is cooled, and the first fluid 4 in a two-phase state entering the second passage 60 evaporates.

[0082] As shown in Fig. 1, the first fluid 4 in expanded gaseous state, flowing downstream of the second passage 60, then reaches the first pipe 12. Advantageously, a pipe 48 is connected to the first pipe 12 at its second portion 30, more particularly between the first heat exchange element 40 and the second compression element 14b. The first fluid 4 in expanded gaseous state is thus mixed with the first fluid 4 from the first heat exchange element 40 and this mixture is sucked into the third portion 32 of the first pipe 12 by the second compression element 14b.

[0083] As shown in FIG. 1 , the management system 1 includes a phase separation device 62 for the first fluid 4 attached to the second piping 16 downstream of the cooling device 50, and the management system 1 includes a return pipe 64 extending between the phase separation device 62 and the first piping 12, through which the first fluid 4 in a gaseous state flows.

[0084] The separation device 62 includes a phase separator main section 66 and an expansion element 68 disposed on the second pipe 16 upstream of the phase separator main section 66. The expansion element 68 enables the first fluid 4 flowing to the phase separator main section 66 to have a pressure substantially the same as the pressure of the first fluid 4 contained in the first tank 2, i.e., atmospheric pressure.

[0085] More specifically, it is noted that the first fluid 4 in liquid state flowing through the second pipe 16 to the first tank 2 expands, i.e. its pressure is reduced, before reaching the first tank 2 in order to match the pressure of the first fluid 4 present in the second pipe with the pressure of the first fluid 4 contained in the first tank 2. The expansion of the first fluid 4 through the expansion element 68 changes the state of the first fluid 4, so that it passes from a liquid state to a two-phase state in which one part of the first fluid 4 is in a liquid state and another part is in a gaseous state. This reduction in pressure also reduces the temperature of the first fluid 4. For example, the first fluid 4 may be expanded to a pressure of approximately 1.2 bar, causing the first fluid 4 to change from a pressure of about 24 bar upstream of the expansion element 68 to a pressure of about 1.2 bar downstream of the expansion element 68, with the first fluid 4 having a temperature of about -50°C.

[0086] The first fluid 4 then flows to the main phase separator 66, where the first fluid 4 is in a liquid state and / or in a two-phase state depending on the exact temperature of the first fluid 4. The main phase separator 66 is configured to separate the phases present in the first fluid 4 flowing from the expansion element 68 to the first tank 2. That is, the main phase separator 66 is configured to separate the first fluid 4 in a liquid state from the first fluid 4 in a gaseous state. The first fluid 4 in a liquid state separated in the main phase separator 66 then flows to the first tank 2, and the first fluid 4 in a gaseous state moves through the return pipe 64 to the first portion 28 of the first pipe 12.

[0087] Advantageously, the second pipe 16 opens into the first tank 2, in particular into a fluid outlet 65 at the bottom of the first tank 2, so that the first fluid 4 in liquid state flows from the phase separator main part 66 through the second pipe 16 to the bottom of the first tank 2. According to an alternative, the second pipe 16 opens at the top 10 of the first tank 2, so that the first fluid 4 in liquid state is for example sprayed at the top 10 of the first tank 2, thus cooling the first fluid 4 in gaseous state present at the top 10 of the first tank 2.

[0088] In the example shown in FIG. 1 herein, the management system 1 includes an expansion block 70 for expanding the first fluid 4, arranged on the return line 64 and configured to cause the first fluid 4, for example in a gaseous state, to flow through the return line 64 and change its pressure from 1.2 bar to atmospheric pressure.

[0089] The management system 1 further includes an exhaust pipe 72 that is connected to the return pipe 64 downstream of the expansion block 70 and opens to the environment external to the management system 1 .

[0090] The management system 1 includes a control valve 74 for controlling the flow rate of the first fluid 4 in a gaseous state, which is disposed on the discharge pipe 72 to control the flow rate of the first fluid 4 discharged to the external environment of the management system 1.

[0091] Before describing the supply pipes 15, the cooling pipes 18, the management pipes 20 and the cooling units 24 will now be described in more detail, with particular reference to FIG.

[0092] 1, the cooling pipe 18 extends between the second pipe 16 and the first pipe 12. Thus, the first fluid 4 flows from the second pipe 16 to the first pipe 12 through the cooling pipe 18.

[0093] According to one feature of the invention, the cooling pipe 18 is connected to the second pipe 16 downstream of the cooling device 50. The first fluid 4 flowing through the cooling pipe 18 from the second pipe 16 to the first pipe 12 passes through at least a portion of the pipe 48 and is mixed with the first fluid 4 flowing through the pipe 48 downstream of the cooling device 50. Thus, the first fluid 4 from the cooling pipe 18 is injected between the first heat exchange element 40 and the second compression element 14b and is mixed with the first fluid 4 flowing through the second portion 30 of the first pipe 12.

[0094] According to the invention, as shown in Fig. 1, the management system 1 comprises a control pipe 20 for controlling the state of the second fluid 8, in particular its pressure and / or temperature, through which the second fluid 8 taken from the second tank 6 in liquid state is intended to flow. To this end, the control pipe 20 comprises a liquid inlet 76, for example located at the bottom of the second tank 6, in contact with the second fluid 8 in liquid state contained in the second tank 6.

[0095] According to an embodiment of the present invention, the management system 1 comprises at least one pump element 78 arranged on the managed piping 20 upstream of the cooling unit 24. The pump element 78 is configured to cause the second fluid 8 in liquid state to flow through the managed piping 20. To this end, the pump element 78 is attached to the liquid inlet 76. In other words, the pump element 78 is immersed in the second fluid 8 in liquid state contained in the second tank 6. However, the pump element 78 can be attached anywhere on the managed piping 20, as long as it pumps the second fluid 8 in liquid state through the managed piping 20.

[0096] The pump element 78 increases the pressure of the second fluid 8 in a liquid state flowing through the management piping 20. For example, the second fluid 8 in a liquid state flowing downstream of the pump element 78 has a pressure of about 4 bar, and as a result, the pump element 78 changes the pressure of the second fluid 8 in a liquid state from atmospheric pressure upstream of the pump element 78 to a pressure of about 4 bar downstream of the pump element 78.

[0097] 1 , the management line 20 includes a liquid outlet 22, and the second fluid 8 in liquid state flows through the management line 20 to the liquid outlet 22. According to one embodiment, the liquid outlet 22 may include a spray element capable of spraying the second fluid 8 in liquid state from the management line 20 at the top 11 of the second tank 6.

[0098] According to the invention, the management system 1 comprises a cooling unit 24 for cooling the second fluid 8 flowing through the management piping 20, the cold generated by the cooling unit 24 being generated by evaporation of the first fluid 4 flowing through the cooling tube 18. The management piping 20 thus comprises a first portion 80 upstream of the cooling unit 24 and a second portion 82 downstream of the cooling unit 24. The second fluid 8 in liquid state flowing through the second portion 82 of the management piping 20 thus has a temperature below the temperature of the second fluid 8 in liquid state flowing through the first portion 80 of the management piping 20.

[0099] 1 , the cooling unit 24 includes at least a heat exchanger 84 and an expansion element 86 attached to the cooling pipes 18 upstream of the heat exchanger 84, where the heat exchanger 84 is configured to exchange heat between the first fluid 4 flowing through the cooling pipes 18 and the second fluid 8 flowing through the management piping 20. It should be noted that the heat exchanger 84 is attached to both the cooling pipes 18 and the management piping 20 such that the first fluid 4 and the second fluid 8 pass through the heat exchanger 84.

[0100] To this end, the heat exchanger 84 includes at least a first passage 88 constituting the cooling pipe 18 and a second passage 90 constituting the management pipe 20, and an expansion element 86 is disposed upstream of the first passage 88. The first fluid 4 flowing through the cooling pipe 18 passes through the heat exchanger 84 through the first passage 88, and the second fluid 8 flowing through the management pipe 20 passes through the heat exchanger 84 through the second passage 90. Thus configured, the heat exchanger 84 exchanges thermal energy between the first fluid 4 flowing through the cooling pipe 18 and the second fluid 8 flowing through the management pipe 20, and the exchange of thermal energy between the first fluid 4 flowing through the cooling pipe 18 and the second fluid 8 flowing through the management pipe 20 is specifically performed in the first passage 88 and the second passage 90 of the heat exchanger 84. Due to the thermal energy exchanged between the first fluid 4 and the second fluid 8, the temperature of the second fluid 8 is lowered, and the second fluid 8 transfers thermal energy to the first fluid 4.

[0101] Moreover, this transfer of thermal energy is achieved thanks to the presence of an expansion element 86 which reduces the pressure of the first fluid 4 flowing through the cooling tube 18 and accelerates its change of state.

[0102] As shown in Fig. 1, the expansion element 86 of the cooling unit 24 is attached to the cooling pipe 18 upstream of the first passage 88. In other words, it should be noted that the first fluid 4 in liquid state, which is fed to the first passage 88, expands before reaching the first passage 88, i.e., it loses pressure and evaporates in the first passage 88. This expansion causes the first fluid 4 to change state, passing from a two-phase state to a gaseous state in the second passage 90. It should be noted that the first fluid 4 is therefore expanded to a pressure of about 3 bar, so that the first fluid 4 may change from a pressure of about 24 bar upstream of the expansion element 86 to a pressure of 3 bar downstream of the expansion element 86.

[0103] The reduction in pressure of the first fluid 4 through the expansion element 86 changes the state of the first fluid 4 and in parallel reduces its temperature. For example, the first fluid 4 may have a temperature of about 14° C. upstream of the expansion element 86 and a temperature of about −30° C. between the expansion element 86 and the first passage 88 of the heat exchanger 84.

[0104] Advantageously, the temperature difference between the first fluid 4 flowing through the first passage 88 and the second fluid 8 in liquid state flowing through the second passage 90 causes the second fluid 8 in liquid state flowing through the second passage 90 to cool and the first fluid 4 in two-phase state entering the first passage 88 to evaporate. Now, the second fluid 8 flowing through the second passage 90 transfers thermal energy to the first fluid 4 flowing through the first passage 88, causing the temperature of the first fluid 4 to increase as it passes through the first passage 88, resulting in its state changing from two-phase to gaseous.

[0105] For example, the temperature of the second fluid 8 in liquid state is approximately 0°C in the first portion 80 of the management piping 20, i.e., upstream of the second passage 90 of the heat exchanger 84, and is approximately -10°C in the second portion 82 of the management piping 20, i.e., downstream of the second passage 90.

[0106] Furthermore, the first fluid 4 flowing through the cooling pipe 18 upstream of the expansion element 86 is in a liquid state, the first fluid 4 flowing through the cooling pipe 18 between the expansion element 86 and the heat exchanger 84 is in a two-phase state, and the first fluid 4 flowing through the cooling pipe 18 is in a gaseous state in and downstream of the heat exchanger 84. For example, the temperature of the first fluid 4 flowing through the cooling pipe 18 upstream of the expansion element 86 is about 14°C, the temperature of the first fluid 4 flowing through the cooling pipe 18 between the expansion element 86 and the heat exchanger 84 is about -30°C, and the temperature of the first fluid 4 flowing downstream of the heat exchanger 84 is about -3°C.

[0107] Advantageously, the expansion element 86, the expansion device 56 and the first compression element 14a are arranged to bring the first fluid 4 to the same pressure. The first compression element 14a therefore increases the pressure of the first fluid 4 flowing through the first pipe 12, for example to a pressure of 3 bar. The expansion element 86 and the expansion device 56 reduce the pressure of the first fluid 4 flowing through the cooling tube 18 and the pipe 48 to a pressure similar to that of the first fluid 4 flowing through the second portion 30 of the first pipe 12, i.e. for example to a pressure of 3 bar. The first fluid 4 in gaseous state flowing through the pipe 48 downstream of the cooling device 50 is therefore at a pressure of for example 3 bar, and the first fluid 4 in gaseous state flowing through the cooling tube 18 downstream of the heat exchanger 84 is also at a pressure of 3 bar.

[0108] The supply tube 15 will now be described in more detail, with particular reference to FIG.

[0109] As a reminder, the supply pipe 15 extends between the second pipe 16 and a consumer 17 that uses the first fluid 4 as fuel, such that the first fluid flows through the supply pipe 15 from the second pipe 16 to the consumer 17. A pump element 19 attached to the supply pipe 15 is, for example, configured to force the first fluid 4 to flow through the supply pipe 15 to the consumer 17.

[0110] According to the invention, as shown in Figure 1, the supply pipe 15 is connected to the second pipe 16 at a junction point 21 located on the second pipe 16 between the third heat exchange element 38 and the cooling device 50. That is, the supply pipe 15 is connected to the second pipe 16 between the third heat exchange element 38 and the cooling device 50. It should be noted that in this configuration the first fluid 4 flowing through the supply pipe towards the consumer 17 is in liquid form.

[0111] Furthermore, the first fluid 4 flows through the second pipe 16 between the third heat exchange element 38 and the cooling device 50 at a temperature of, for example, about 43° C. and a pressure of about 24 bar. The first fluid 4 flowing through the supply pipe 15 at least between the split point 21 and the pump element 19 also has a similar temperature and pressure as the first fluid flowing through the second pipe 16 between the third heat exchange element 38 and the cooling device 50, i.e. a temperature of about 43° C. and a pressure of about 24 bar.

[0112] It follows from the above that the pump element 19 therefore defines two portions of the supply pipe 15, namely a forward portion 23 in front of the pump element 19 and a rearward portion 25 behind the pump element 19. More specifically, the forward portion 23 of the supply pipe 15 extends from the split point 21 to the pump element 19, whilst the rearward portion 25 of the supply pipe 15 extends from the pump element 19 to the consumer 17.

[0113] According to the invention, the pump element 19 increases the pressure of the first fluid 4 flowing through the supply pipe 15 by at least 5 bar. Advantageously, the pump element 19 increases the pressure of the first fluid 4 flowing through the supply pipe 15 by approximately 10-20 bar, not exceeding 35 bar. For example, the pressure of the first fluid 4 flowing through the front section 23 is approximately 24 bar, while the pressure of the first fluid 4 flowing through the rear section 25 is approximately 45 bar. Advantageously, the pressure of the first fluid 4 flowing through the rear section 25 is approximately 35-55 bar. It should be noted that the pressure delivered to the consumer 17 in this case is therefore a combination of the force exerted by the compression element or elements 14 and the force exerted by the pump element 19, as a result of which it is possible to liquefy the first fluid, manage the pressure of the second fluid and supply fuel to the consumer unit using smaller, cheaper and more reliable pump elements.

[0114] Furthermore, the temperature of the first fluid 4 flowing through the supply pipe 15 is, for example, 20° C. to 40° C. At this temperature, specifically when the pressure of the first fluid 4 is 35 to 55 bar, the first fluid 4 is in a liquid state.

[0115] According to an alternative embodiment of the invention, the pump element 19 is arranged directly at the fluid outlet of the phase separation device 44 which opens into the second pipe 16. In this configuration, the pump element 19 pumps the first fluid 4 through the second pipe 16 directly to the first tank 2 and then through the supply pipe 15 to the consumer machine 17.

[0116] Furthermore, the circuit 1 includes a control valve 27 for controlling the flow rate of the first fluid 4 through the supply line 15. The control valve 27 allows the first fluid 4 to pass, such that the control valve 27 can adjust the amount of the first fluid 4 flowing to the consumer 17. For example, the control valve 27 adjusts the flow rate of the first fluid 4 through the supply line 15 such that the first fluid 4 has a flow rate that matches the requirements of the consumer unit. The control valve 27 thus matches the flow rate of the first fluid 4 through the supply line 15 to the requirements of the consumer 17 for fuel.

[0117] Advantageously, the control valve 27 is mounted in the forward part 23 of the supply pipe 15, i.e. the control valve 27 is arranged in the supply pipe 15 between the split point 21 and the pump element 19. The control valve 27 therefore regulates the flow rate of the first fluid 4 through the supply pipe 15 upstream of the pump element 19. However, a circuit in which the control valve 27 is mounted between the pump element 19 and the consumer 17, i.e. the rear part 25 of the supply pipe 15, would not depart from the scope of the invention.

[0118] According to another embodiment, shown in Figure 3, the circuit 1 includes a conveying pipe 31 extending between the management pipe 20 and the supply pipe 15. The conveying pipe 31 thus fluidly connects the management pipe 20 to the supply pipe 15.

[0119] To this end, the management pipe 20 comprises a conveying pipe 31 and a crossing section 33 of the management pipe 20, so that at least a part of the second fluid 8 flowing in the management pipe 20 flows through the conveying pipe 31 in the crossing section 33 to the supply pipe 15. The crossing section 33 is in this case arranged in the first part 80 of the management pipe 20, but it could be arranged in the second part 82 of the management pipe 20 without thereby departing from the scope of the invention.

[0120] On the one hand, the supply pipe 15 includes a branch section 35 with the carrier pipe 31, so that the second fluid 8 flowing in the carrier pipe 31 flows through the branch section 35 into the supply pipe 15. In this configuration, the second fluid 8 can be supplied to the consumer 17, which can use the second fluid 8 as fuel. The branch section 35 is in this case arranged in the front part 23 of the supply pipe 15, but it can also be arranged in the rear part 25 of the supply pipe 15, without thereby departing from the scope of the invention.

[0121] Furthermore, in the branch section 35, the second fluid 8 from the management pipe 20 flowing through the conveying pipe 31 is mixed with the first fluid 4 flowing in the supply pipe 15. It should be noted that downstream of the branch section 35, the mixture of the first fluid 4 and the second fluid 8 flows to the consumer machine 17.

[0122] Furthermore, the conveying pipe 31 includes a regulating valve 37 for regulating the flow rate of the second fluid 8 flowing through the conveying pipe 31. It is noted that the regulating valve 37 allows the second fluid 8 to flow through the conveying pipe 31 to the supply pipe 15 and to the consumer machine 17. It is noted that the flow rate of the second fluid 8 in the conveying pipe 31 is controlled by the regulating valve 37, and as a result the amount of the second fluid 8 flowing through the supply pipe 15 is regulated by this regulating valve 37.

[0123] It should be noted that the consuming machine 17 may use the first fluid 4 as fuel, but also the second fluid 8 and / or a mixture of the first fluid 4 and the second fluid 8 as fuel.

[0124] A second embodiment of the present invention will now be described with particular reference to Figure 2. The elements which differentiate the second embodiment from the first embodiment will be described below, with reference to the detailed description of the first embodiment for the identical elements.

[0125] As shown in FIG. 2, the circuit 1 includes a first pipe 92 and a second pipe 94, each of which independently extends between the second piping 16 and the first piping 12.

[0126] The first pipe 92 is connected on the one hand to the second piping 16 and on the other hand to the third portion 32 of the first piping 12 between the second heat exchange element 42 and the third compression element 14c. It should be noted that the first fluid 4 flowing in the first pipe 92 mixes with the first fluid 4 flowing in the third portion 32 of the first piping 12 at a location between the second heat exchange element 42 and the third compression element 14c.

[0127] The circuit 1 comprises a first cooling device 96 attached to the second piping 16 and the first pipe 92, the first cooling device 96 comprising a first heat exchanger 98 and a first expansion device 100 arranged on the first pipe 92 upstream of the first heat exchanger 98. The first heat exchanger 98 is configured to exchange thermal energy between the first fluid 4 flowing in the first pipe 92 and the first fluid 4 flowing in the second piping 16. To this end, the first heat exchanger 98 comprises a first conduit 102 constituting the second piping 16 and a second conduit 104 constituting the first pipe 92. It is to be noted that the first fluid 4 flowing in the second piping 16 passes through the first heat exchanger 98 through the first conduit 102, and the first fluid 4 flowing in the first pipe 92 passes through the first heat exchanger 98 through the second conduit 104.

[0128] Further, it is noted that the first intersection 521 of the first pipe 92 and the second piping 16 is located between the phase separation device 44 and the first cooling device 96. Thus, the first fluid 4 flowing through the first intersection 521 can continue to flow through the second piping 16 to the first cooling device 96 and / or continue to flow through the first pipe 92 to the first piping 12.

[0129] The first expansion device 100 is in this case configured to reduce the pressure of the first fluid 4 in liquid state flowing through the first pipe 92 to a pressure approximately equal to the pressure of the first fluid 4 in gaseous state flowing through the third portion 32 of the first piping 12. For example, the pressure of the first fluid 4 flowing downstream of the first cooling device 96 is approximately 10.5 bar, and the first expansion device 100 changes the pressure of the first fluid 4 flowing through the first pipe 92 from a pressure of approximately 24 bar upstream of the first expansion device 100 to a pressure of approximately 10.5 bar downstream of the first expansion device 100.

[0130] The heat exchange between the first fluid 4 flowing through the second piping 16 and the first fluid 4 flowing through the first pipe 92 takes place in the first heat exchanger 98, more specifically in the first conduit 102 and the second conduit 104. The first fluid 4 flowing through the first conduit 102 gives up heat energy to the expanded first fluid 4 flowing through the second conduit 104. In other words, the first fluid 4 flowing through the second conduit 104 cools the first fluid 4 flowing through the first conduit 102, so that the temperature of the first fluid 4 flowing through the first conduit 102 decreases, while the temperature of the first fluid 4 flowing through the second conduit 104 increases. The increase in temperature of the first fluid 4 flowing through the second conduit 104 causes the first fluid 4 to transition from a two-phase state to a gaseous state.

[0131] 2, the second pipe 94 is connected on the one hand to the second piping 16 and on the other hand to the second portion 30 of the first piping 12 between the first heat exchange element 40 and the second compression element 14b. It should be noted that the first fluid 4 flowing in the second pipe 94 mixes with the first fluid 4 flowing in the second portion 30 of the first piping 12 at a location between the first heat exchange element 40 and the second compression element 14b.

[0132] Additionally, the second pipe 94 is connected to the second piping 16 downstream of the first cooling device 96. It should be noted that a second intersection 522 of the second pipe 94 and the second piping 16 is located between the first cooling device 96 and the phase separation device 62. The first fluid 4 flowing through the second pipe 94 originates from the first fluid 4 cooled by the first cooling device 96 and flowing through the second piping 16.

[0133] The circuit 1 comprises a second cooling device 106 attached to the second piping 16 and the second pipe 94, the second cooling device 106 comprising a second heat exchanger 108 and a second expansion device 110 arranged on the second pipe 94 upstream of the second heat exchanger 108. The second heat exchanger 108 is configured to exchange thermal energy between the first fluid 4 flowing in the second pipe 94 and the first fluid 4 flowing in the second piping 16 downstream of the first cooling device 96. To this end, the second heat exchanger 108 comprises a first conduit 112 constituting the second piping 16 and a second conduit 114 constituting the second pipe 94. It is to be noted that the first fluid 4 flowing in the second piping 16 passes through the second heat exchanger 108 through the first conduit 112, and the first fluid 4 flowing in the second pipe 94 passes through the second heat exchanger 108 through the second conduit 114.

[0134] The second expansion device 110 is in this case configured to reduce the pressure of the first fluid 4 in liquid state flowing through the second pipe 94 to a pressure approximately equal to the pressure of the first fluid 4 in gaseous state flowing through the second portion 30 of the first piping 12. For example, the pressure of the first fluid 4 flowing downstream of the second cooling device 106 is approximately 3 bar and the second expansion device 110 changes the pressure of the first fluid 4 flowing through the second pipe 94 from a pressure of approximately 24 bar upstream of the first expansion device 100 to a pressure of approximately 3 bar downstream of the second expansion device 110.

[0135] The expansion of the first fluid 4 flowing through the second pipe 94 from a pressure of about 24 bar to a pressure of about 3 bar reduces the temperature of the first fluid 4 flowing through the second conduit 114. The first fluid 4 flowing between the second expansion device 110 and the second conduit 114 is in a two-phase state, and the first fluid 4 vaporizes as it passes through the second conduit 114.

[0136] The heat exchange between the first fluid 4 flowing through the second pipe 16 and the first fluid 4 flowing through the second pipe 94 takes place in the second heat exchanger 108, more specifically in the first conduit 112 and the second conduit 114. The first fluid 4 flowing through the first conduit 112 gives up heat energy to the expanded first fluid 4 flowing through the second conduit 114. In other words, the first fluid 4 flowing through the second conduit 114 cools the first fluid 4 flowing through the first conduit 112, so that the temperature of the first fluid 4 flowing through the first conduit 112 decreases, while the temperature of the first fluid 4 flowing through the second conduit 114 increases. Due to the increase in temperature of the first fluid 4 flowing through the second conduit 114, the first fluid 4 transitions from a two-phase state to a gaseous state.

[0137] The cooling pipe 18 and the branch 116 of the second pipe 16 are arranged between the first cooling device 96 and the second cooling device 106. It should be noted that the first fluid 4 flowing in the second pipe 16 downstream of the first cooling device 96 can flow through the cooling pipe 18 to the cooling unit 24, or through the second pipe 94 to the first pipe 12, or through the second pipe 16 to the first tank 2. Advantageously, the cooling pipe 18 and the branch 116 of the second pipe 16 are attached between the second intersection 522 of the second pipe 16 and the second pipe 94 and the first cooling device 96.

[0138] In this configuration, the cooling tube 18 extends between the second piping 16 and the second pipe 94, and the cooling tube 18 is connected to the second pipe 94 downstream of the second cooling device 106. It should be noted that the first fluid 4 in a gaseous state flowing through the cooling tube 18 downstream of the cooling unit 24 mixes with the first fluid 4 in a gaseous state flowing through the second pipe 94 downstream of the second cooling device 106 before being entrained by the first fluid 4 in a gaseous state flowing through the second portion 30 of the first piping 12.

[0139] Therefore, from the above, a portion of the first fluid 4 is recirculated by the management system 1, and this portion of the first fluid 4 mainly helps to cool the first fluid 4 and / or the second fluid 8.

[0140] According to one feature of the invention, the supply pipe 15 extends from the cooling pipe 18 to the consumer 17, and a branch 116 of the supply pipe 15 and the cooling pipe 18 is located between the chiller 96 and the cooling unit 24. It should be noted that the first fluid 4 flowing through the supply pipe 15 is first cooled while passing through the first cooling pipe 96 before flowing through the supply pipe 15 to the consumer 17.

[0141] Furthermore, the supply pipe 15 extends from the cooling pipe 18 to the consumer 17, and a junction 29 between the supply pipe 15 and the cooling pipe 18 is located upstream of the expansion element 86 of the cooling unit 24. It should be noted that the first fluid 4 flowing through the cooling pipe 18 to the expansion element 86 of the cooling unit 24 can flow at the junction 29 through the supply pipe 15 to the consumer 17.

[0142] In this embodiment, the first fluid 4 flowing through the supply conduit 15 to the consumer 17 is cooled by a first cooling device 96 in comparison to the first embodiment. The advantage of this embodiment is that the first fluid 4 is more preferably in liquid form when it flows through the supply conduit 15 to the consumer 17, optimizing the use of the first fluid 4 as fuel by the consumer 17. Furthermore, by reducing the temperature of the first fluid 4, the risk of cavitation occurring in the pump element 19 is reduced.

[0143] However, the invention is not limited to the means and arrangements described and illustrated herein, but extends to all equivalent means and arrangements, and any technically functional combination of such means. In particular, all of the elements that change the pressure, temperature, and / or state of the first fluid 4 and / or the pressure, temperature, and / or state of the second fluid 8 can be modified without detriment to the invention, provided that they provide the functionality described herein.

Claims

1. A circuit (1) through which a first fluid (4) contained in a first tank (2) and a second fluid (8) contained in a second tank (6) can flow, said first fluid (4) having a boiling point lower than the boiling point of said second fluid (8), said circuit (1) comprising at least a first pipe (12) extending from said first tank (2) to a heat exchange element (38, 40, 42), said first fluid (4) taken from said first tank (2) in a gaseous state is intended to flow through said first pipe (12), said heat exchange element (38, 40, 42) being configured to condense said first fluid (4), said circuit (1) comprising a second pipe (16) extending from said heat exchange element (38, 40, 42) to said first tank (2), said first fluid (4) in a liquid state and / or in a two-phase state being intended to flow through said first pipe (12), is intended to flow through said second pipe (16), said circuit (1) comprising at least one management pipe (20) for managing the state of said second fluid (8) intended to flow through said second fluid (8) taken in liquid state from said second tank (6), said circuit (1) comprising at least a supply pipe (15) extending from said second pipe (16) to said consumer (17) for supplying at least said first fluid (4) to said consumer (17) using said first fluid as fuel, said supply pipe (15) being configured for at least said first fluid (4) in liquid state to flow through said supply pipe (15), said supply pipe (15) comprising at least one pump element (19) for increasing the pressure of said first fluid (4) in said supply pipe (15).

2. 2. The circuit (1) according to claim 1, comprising at least one cooling pipe (18) intended for the flow of the first fluid (4) extending from the second pipe (16) to the first pipe (12), the first pipe (12) comprising at least a first compression element (14, 14a) and a second compression element (14, 14b, 14c), the cooling pipe (18) being connected to the first pipe (12) between the first compression element (14, 14a) and the second compression element (14, 14b, 14c).

3. 2. The circuit (1) according to claim 1, comprising at least one cooling unit (24) for cooling the second fluid (8) in a liquid state flowing through the management piping (20) for managing the state of the second fluid (8), wherein the cold air generated by the cooling unit (24) is generated by evaporation of the first fluid (4) flowing through the at least one cooling pipe (18) extending from the second piping (16) to the first piping (12) and intended for the first fluid (4) to flow through.

4. 4. The circuit (1) of claim 3, wherein the cooling unit (24) includes at least a heat exchanger (84) and an expansion element (86), the heat exchanger (84) exchanging thermal energy between the first fluid (4) flowing through the cooling pipe (18) and the second fluid (8) flowing through the management piping (20).

5. 5. The circuit (1) according to claim 4, wherein the heat exchanger (84) includes at least a first passage (88) constituting the cooling pipe (18) and a second passage (90) constituting the management pipe (20), and the expansion element (86) is disposed between the first passage (88) and the second pipe (16).

6. The circuit (1) according to any one of claims 1 to 5, comprising at least one pipe (48) extending from the second piping (16) to the first piping (12) and through which the first fluid (4) flows, the circuit (1) comprising at least one cooling device (50) for cooling the first fluid (4) flowing in the second piping (16), the cold air generated by the cooling device (50) being produced by evaporation of the first fluid (4) flowing in the pipe (48).

7. 7. The circuit (1) according to claim 6, wherein the supply pipe (15) is connected to the second pipe (16) at a branch point (21) located on the second pipe (16) between the heat exchange element (38, 40, 42) and the cooling device (50).

8. 8. The circuit (1) according to claim 7, wherein the supply pipe (15) is connected to the second pipe (16) at the split point (21) located on the second pipe (16) between a separation element (44) and the cooling device (50).

9. 6. The circuit (1) according to any one of claims 1 to 5, comprising at least one phase separation element (44) for the first fluid (4) arranged on the second piping (16), the first fluid (4) flowing from the phase separation element (44) through the second piping to the first tank (2), the circuit (1) comprising a gas pipe (46) extending from the separation element (44) to the second piping (16).

10. A circuit (1) comprising at least one pipe (48) extending from the second piping (16) to the first piping (12) and through which the first fluid (4) flows, the circuit (1) comprising at least one cooling device (50) for cooling the first fluid (4) flowing through the second piping (16), the cold air generated by the cooling device (50) being produced by evaporation of the first fluid (4) flowing through the pipe (48), The circuit (1) according to any one of claims 3 to 5, wherein the supply pipe (15) extends from the cooling pipe (18) to the consumer (17), and a branch point (29) between the supply pipe (15) and the cooling pipe (18) is arranged between the cooling device (50) and the cooling unit (24).

11. The circuit (1) includes at least one pipe (48) extending from the second piping (16) to the first piping (12) and through which the first fluid (4) flows, the circuit (1) includes at least one cooling device (50) for cooling the first fluid (4) flowing in the second piping (16), the cold air generated by the cooling device (50) being generated by evaporation of the first fluid (4) flowing in the pipe (48), 5. The circuit (1) according to claim 4, wherein the supply pipe (15) extends from the cooling pipe (18) to the consumer (17), and the branch point (29) between the supply pipe (15) and the cooling pipe (18) is arranged between the expansion element (86) of the cooling unit (24) and the cooling device (50).

12. The circuit (1) according to any one of the preceding claims, comprising a control valve (27) for controlling the flow rate of the first fluid (4) through the supply pipe (15).

Images