WO2024009949A1 - Float and gas pressure control method - Google Patents

Abstract

This float comprises: a floating body; a tank which is provided to the floating body and which can store liquid carbon dioxide; a supply line for supplying liquid carbon dioxide into the tank; a discharge line for discharging the liquid carbon dioxide in the tank to the outside of the tank; a gas line which is connected to the tank and in which carbon dioxide gas can flow; a compressor which is provided to the gas line, and which compresses the carbon dioxide gas flowing in the gas line; and a heating unit which is disposed on the gas line on the upstream side of the compressor, and which can heat the carbon dioxide gas flowing in the gas line.

Description

Floating body, gas pressure control method

The present disclosure relates to a floating body and a gas pressure control method.
This application claims priority to Japanese Patent Application No. 2022-108305 filed in Japan on July 5, 2022, the contents of which are incorporated herein.

Patent Document 1 discloses the configuration of a gas processing system that supplies liquefied gas from a storage tank of a bunkering vessel to a fuel tank of a gas-propelled vessel. This gas processing system includes a bunkering line, an evaporated gas return line, and a reliquefaction device (bunkering management section). The bunkering line supplies the liquefied gas from the storage tank to the fuel tank. The evaporative gas return line transmits evaporative gas generated in the fuel tank to the bunkering vessel during bunkering via the bunkering line. The reliquefaction device reliquefies and returns evaporated water from the storage tank to adjust the internal pressure of the storage tank. In such a configuration, a compressor is provided upstream of the reliquefaction device. The compressor compresses the evaporated gas in the storage tank and sends it to the reliquefaction device.

By the way, ships equipped with tanks capable of storing liquefied carbon dioxide may also be equipped with a compressor. In a tank capable of storing liquefied carbon dioxide, the liquefied carbon dioxide evaporates within the tank and carbon dioxide gas is generated. The compressor compresses the generated carbon dioxide gas. In the case of such ships, compressors are used to manage the pressure inside the tanks through which carbon dioxide gas flows and the piping connected to the tanks.

Special Publication No. 2021-517878

By the way, when a compressor for compressing carbon dioxide gas is provided, the carbon dioxide gas may solidify and dry ice may be produced for the following reasons. That is, when the compressor is in operation, the flow rate of carbon dioxide gas increases, for example, on the inlet side of the compressor. An increase in the flow rate of carbon dioxide gas results in a decrease in the local static pressure of carbon dioxide gas. When a local static pressure drop in carbon dioxide gas occurs, the likelihood of dry ice formation increases.

The present disclosure has been made to solve the above problems, and aims to provide a floating body and a gas pressure control method that can suppress the generation of dry ice.

In order to solve the above problems, a floating body according to the present disclosure includes a floating body main body, a tank, a supply line, a discharge line, a gas line, a compressor, and a heating section. The tank is provided in the floating body. The tank can store liquefied carbon dioxide. The supply line supplies the liquefied carbon dioxide into the tank. The discharge line discharges the liquefied carbon dioxide in the tank to the outside of the tank. The gas line is connected to the tank so that carbon dioxide gas can flow therethrough. The compressor is provided in the gas line. The compressor compresses the carbon dioxide gas flowing through the gas line. The heating section is provided upstream of the compressor in the gas line. The heating section can heat the carbon dioxide gas flowing through the gas line.

A gas pressure control method according to the present disclosure is a gas pressure control method in a floating body as described above, which includes the step of detecting the temperature of carbon dioxide gas, and the temperature of the carbon dioxide gas being equal to or lower than a predetermined lower limit threshold. and heating the carbon dioxide gas. In the step of detecting the temperature of the carbon dioxide gas, the temperature of the carbon dioxide gas flowing through the gas line is detected. In the step of determining whether the temperature of the carbon dioxide gas is below a predetermined lower limit threshold, the step of determining whether the detected temperature of the carbon dioxide gas is below a predetermined lower limit threshold. judge. In the step of heating the carbon dioxide gas, if it is determined that the temperature of the carbon dioxide gas is equal to or lower than the lower limit threshold, the carbon dioxide gas is caused to flow through the gas line in the heating section.

According to the floating body and gas pressure control method of the present disclosure, generation of dry ice can be suppressed.

FIG. 1 is a plan view showing a schematic configuration of a floating body according to an embodiment of the present disclosure. It is a sectional side view showing a tank and a gas line provided in a floating body concerning an embodiment of the present disclosure. In the floating body according to the embodiment of the present disclosure, it is a diagram showing the flow of carbon dioxide gas when carbon dioxide gas is supplied into the tank. In the floating body according to the embodiment of the present disclosure, it is a diagram showing the flow of carbon dioxide gas when the carbon dioxide gas is discharged to the outside of the tank. FIG. 3 is a diagram showing the flow of carbon dioxide gas when circulating carbon dioxide gas in a tank in a floating body according to an embodiment of the present disclosure. It is a diagram showing a hardware configuration of a control device provided in a floating body according to an embodiment of the present disclosure. FIG. 2 is a functional block diagram of a control device provided in a floating body according to an embodiment of the present disclosure. It is a flowchart which shows the procedure of the gas pressure management method in a floating body concerning an embodiment of this indication.

A floating body and a gas pressure control method according to an embodiment of the present disclosure will be described below with reference to FIGS. 1 to 8.
(Ship configuration)
FIG. 1 is a plan view showing a schematic configuration of a floating body according to an embodiment of the present disclosure.
In the embodiment of the present disclosure, a ship (floating body) 1 that is a floating body transports liquefied carbon dioxide. As shown in FIG. 1, this ship 1 includes at least a hull 2 as a floating body body and tank equipment 10.

(hull configuration)
The hull 2 has a pair of sides 3A and 3B forming its outer shell, a bottom (not shown), and an upper deck 5. The sides 3A and 3B have a pair of side skins forming port and starboard sides, respectively. The bottom (not shown) has a bottom skin that connects these sides 3A, 3B. The outer shell of the hull 2 has a U-shape in a cross section perpendicular to the bow and stern direction Da due to the pair of sides 3A, 3B and the bottom (not shown). The upper deck 5 illustrated in this embodiment is a full deck exposed to the outside. In the hull 2, an upper structure 7 having a living area is formed, for example, on an upper deck 5 on the stern 2b side. Note that the position and size of the upper structure 7 can be changed as appropriate.

A cargo loading compartment (hold) 8 is formed in the hull 2 closer to the bow 2a than the superstructure 7. The cargo loading compartment 8 is recessed from the upper deck 5 toward the bottom of the ship and opens upward.

(Configuration of tank equipment)
A plurality of tank facilities 10 are arranged in the cargo loading compartment 8 in a line in the bow-stern direction Da. In the embodiment of the present disclosure, for example, two tank facilities 10 are arranged at intervals in the bow and stern direction Da.

FIG. 2 is a side sectional view showing a tank and gas line provided in a floating body according to an embodiment of the present disclosure.
As shown in FIG. 2, the tank equipment 10 includes at least a tank 11, a supply line 15, a discharge line 16, a gas line 20, a compressor 30, a heating section 40, and a control device 50. There is.
In this embodiment, the tank 11 is arranged on the hull 2 and has, for example, a cylindrical shape extending in the bow and aft direction Da. The tank 11 can store liquefied carbon dioxide L therein. The tank 11 includes a cylindrical portion 12 and an end plate portion 13. The cylindrical portion 12 extends in the bow and aft direction Da as its longitudinal direction. In this embodiment, the cylindrical portion 12 is formed in a cylindrical shape, and has a circular cross-sectional shape perpendicular to its longitudinal direction. The end plate portions 13 are arranged at both ends of the cylindrical portion 12 in the longitudinal direction. Each end plate portion 13 has a hemispherical shape and closes openings at both ends of the cylindrical portion 12 in the longitudinal direction. Note that the tank 11 is not limited to a cylindrical shape, and may have other shapes such as a spherical shape or a rectangular shape.

The supply line 15 loads liquefied carbon dioxide L supplied from outside the ship, such as a land-based liquefied carbon dioxide supply facility or another ship storing liquefied carbon dioxide, into the tank 11. The supply line 15 passes from the outside of the tank 11 through the top of the tank 11 and reaches the bottom of the tank 11 . The tip 15a of the supply line 15 (in other words, the lower end in the vertical direction Dv) is open at the lower part of the tank 11 and faces downward.

The discharge line 16 discharges the liquefied carbon dioxide L in the tank 11 to a land-based liquefied carbon dioxide storage facility or the like outside the ship. The distal end 16a of the discharge line 16 is connected to a pump 18 disposed at the lower part of the tank 11. The discharge line 16 extends upward from the tip 16a, passes through the top of the tank 11, and reaches the outside of the tank 11. The pump 18 connected to the tip 16a sucks in the liquefied carbon dioxide L in the tank 11 and discharges the sucked liquefied carbon dioxide L to the outside of the tank 11 via the discharge line 16.

The gas line 20 is configured to allow at least the carbon dioxide gas G in the tank 11 to flow therethrough. The carbon dioxide gas G in the tank 11 is lower than 0° C. and higher than the triple point temperature of carbon dioxide. The carbon dioxide gas G in the tank 11 is mainly a so-called boil-off gas obtained by evaporating the liquefied carbon dioxide L stored in the tank 11, and has a temperature of, for example, -56°C to -10°C.

The gas line 20 includes a first pipe section 21, a second pipe section 22, a third pipe section 23, a fourth pipe section 24, a fifth pipe section 25, and a sixth pipe section 26. There is.

The first pipe part 21 is used when sending carbon dioxide gas G supplied from outside the ship into the tank 11. One end 21a of the first pipe portion 21 is configured to be connectable to a supply pipe (not shown) for supplying carbon dioxide gas G from equipment outside the ship. The carbon dioxide gas G supplied from outside the ship has a temperature of, for example, -56°C to -10°C, similar to the boil-off gas described above. The other end 21b of the first tube section 21 is connected to one end 25a of a fifth tube section 25, which will be described later. The first pipe portion 21 is provided with an on-off valve 21v.

The second pipe part 22 is used when discharging the carbon dioxide gas G in the tank 11 to the outside of the ship. One end 22a of the second pipe portion 22 is configured to be connectable to an exhaust pipe (not shown) for discharging carbon dioxide gas G to equipment outside the ship. The other end 22b of the second tube section 22 is connected to the other end 26b of the sixth tube section 26, which will be described later. The second pipe portion 22 is provided with an on-off valve 22v.

The third pipe section 23 is used when sending carbon dioxide gas G into the tank 11. One end 23a of the third pipe portion 23 is connected to the top portion 11t of the tank 11. The other end 23b of the third tube section 23 is connected to the other end 26b of the sixth tube section 26, which will be described later. The third pipe portion 23 is provided with an on-off valve 23v.

The fourth pipe part 24 is used when discharging the carbon dioxide gas G in the tank 11 to the outside of the tank 11. One end 24a of the fourth pipe portion 24 is connected to the top portion 11t of the tank 11. The other end 24b of the fourth tube section 24 is connected to one end 25a of a fifth tube section 25, which will be described later. The fourth pipe portion 24 is provided with an on-off valve 24v.

The fifth tube section 25 is provided between the other end 21b of the first tube section 21 and the other end 24b of the fourth tube section 24, and the heating section 40. One end 25a of the fifth tube section 25 is connected to the other end 21b of the first tube section 21 and the other end 24b of the fourth tube section 24. The other end 25b of the fifth tube section 25 is connected to the inlet of the heating section 40. The fifth pipe portion 25 is provided with an on-off valve 25v. The on-off valve 25v is provided on the upstream side in the direction in which carbon dioxide gas flows with respect to the heating section 40, which will be described later.

The sixth tube section 26 is provided between the heating section 40 and the other end 22b of the second tube section 22 and the other end 23b of the third tube section 23. One end 26a of the sixth tube section 26 is connected to the outlet of the heating section 40. The other end 26b of the sixth tube section 26 is connected to the other end 22b of the second tube section 22 and the other end 23b of the third tube section 23. The sixth pipe portion 26 is provided with a compressor 30 and an on-off valve 25w in the middle thereof. The on-off valve 25w is provided closer to the other end 26b than the compressor 30.

The compressor 30 compresses the carbon dioxide gas G that has flowed in through the fifth pipe section 25 and the sixth pipe section 26. The compressor 30 compresses the carbon dioxide gas G sucked in from the inlet side and discharges it to the other end 26b side of the sixth pipe portion 26. Therefore, the carbon dioxide gas G flows through the sixth pipe portion 26 from the one end 26a side to the other end 26b side.

The heating section 40 is arranged between the fifth tube section 25 and the sixth tube section 26. That is, the heating unit 40 is arranged upstream of the compressor 30. The heating section 40 heats the carbon dioxide gas G flowing through the fifth pipe section 25 . As the heating section 40, for example, a heat exchanger is used. The heating section 40 heats the carbon dioxide gas G flowing through the fifth pipe section 25 . The heating unit 40, for example, heats the carbon dioxide gas G at -56°C to -10°C flowing through the fifth tube part 25 at a temperature higher than -10°C and at the upper limit temperature of the design conditions (for example, about 80°C). You may heat it so that it becomes below.

A sensor 45 is provided in the fifth tube section 25. The sensor 45 detects the temperature of the carbon dioxide gas G flowing through the fifth pipe section 25. The sensor 45 outputs a signal of the detected temperature value to the control device 50.

(Gas line operation)
The gas line 20 as described above has functional configurations as a gas supply line 20F, a gas discharge line 20E, and a gas circulation line 20R, respectively. The gas line 20 can be used by selectively selecting one of the gas supply line 20F, the gas discharge line 20E, and the gas circulation line 20R by switching the opening and closing of the on-off valves 21v to 25v and 25w.

FIG. 3 is a diagram showing the flow of carbon dioxide gas when carbon dioxide gas is supplied into the tank in the floating body according to the embodiment of the present disclosure.
As shown in FIG. 3, the gas supply line 20F is configured by closing the on-off valve 22v and the on-off valve 24v, and opening the on-off valve 21v, the on-off valves 25v, 25w, and the on-off valve 23v. The gas supply line 20F is used to supply carbon dioxide gas G from outside the tank 11 into the tank 11. In this case, carbon dioxide gas G supplied from outside the tank 11 is supplied into the tank 11 via the first pipe section 21, the fifth pipe section 25, the sixth pipe section 26, and the third pipe section 23. . In other words, the gas supply line 20F includes the first pipe section 21, the fifth pipe section 25, the sixth pipe section 26, and the third pipe section 23.

The gas supply line 20F is used for the purpose of cooling the inside of the tank 11 and increasing the pressure inside the tank 11, for example, before supplying the liquefied carbon dioxide L to the tank 11. Furthermore, when the gas supply line 20F discharges the liquefied carbon dioxide L in the tank 11 to the outside of the tank 11 through the discharge line 16, the pressure in the tank 11 decreases as the liquefied carbon dioxide L in the tank 11 decreases. It is used for the purpose of suppressing the decline. Note that the gas supply line 20F may be used in a manner other than that described above.

When carbon dioxide gas G is supplied into the tank 11 through the gas supply line 20F, the carbon dioxide gas G sent into the tank 11 is compressed by operating the compressor 30. Thereby, the pressure of the gas phase within the tank 11 can be increased to match the preset target pressure.

FIG. 4 is a diagram showing the flow of carbon dioxide gas when the carbon dioxide gas is discharged outside the tank in the floating body according to the embodiment of the present disclosure.
As shown in FIG. 4, the gas exhaust line 20E is configured by closing the on-off valve 21v and the on-off valve 23v, and opening the on-off valve 24v, the on-off valves 25v, 25w, and the on-off valve 22v. The gas discharge line 20E is used to discharge carbon dioxide gas G from inside the tank 11 to outside the tank 11. In this case, the carbon dioxide gas G in the tank 11 is discharged to the outside of the tank 11 through the fourth pipe section 24, the fifth pipe section 25, the sixth pipe section 26, and the second pipe section 22. In other words, the gas exhaust line 20E includes the fourth pipe section 24, the fifth pipe section 25, the sixth pipe section 26, and the second pipe section 22.

The purpose of the gas discharge line 20E is, for example, to suppress the pressure in the tank 11 from increasing as the liquefied carbon dioxide L in the tank 11 increases when the liquefied carbon dioxide L is supplied into the tank 11 through the supply line 15. used in Note that the gas exhaust line 20E may be used in a manner other than that described above.

When the carbon dioxide gas G is discharged to the outside of the tank 11 through the gas discharge line 20E, the carbon dioxide gas G to be discharged to the outside of the tank 11 is compressed by operating the compressor 30. Thereby, carbon dioxide gas G can be efficiently discharged. Therefore, the pressure of the gas phase within the tank 11 can be efficiently managed in accordance with a preset target pressure.

FIG. 5 is a diagram showing the flow of carbon dioxide gas when circulating the carbon dioxide gas in the tank in the floating body according to the embodiment of the present disclosure.
As shown in FIG. 5, the gas circulation line 20R is configured by closing an on-off valve 21v and an on-off valve 22v, and opening an on-off valve 24v, on-off valves 25v, 25w, and an on-off valve 23v. In this case, the carbon dioxide gas G in the tank 11 is circulated into the tank 11 via the fourth pipe section 24, the fifth pipe section 25, the sixth pipe section 26, and the third pipe section 23. That is, the gas circulation line 20R includes the fourth pipe section 24, the fifth pipe section 25, the sixth pipe section 26, and the third pipe section 23.

The gas circulation line 20R is used when pressurizing the carbon dioxide gas G in the tank 11. In this case, by operating the compressor 30, the carbon dioxide gas G taken out from inside the tank 11 to the gas circulation line 20R outside the tank 11 is compressed. This increases the pressure of carbon dioxide gas G. By returning the carbon dioxide gas G whose pressure has been increased into the tank 11, the pressure of the gas phase within the tank 11 is increased. Therefore, the pressure of the gas phase within the tank 11 can be efficiently managed in accordance with a preset target pressure. Note that the gas circulation line 20R may be used in a manner other than that described above. In the present embodiment, a reliquefaction device (not shown) that reliquefies carbon dioxide gas G (so-called boil-off gas) generated by evaporation in the tank 11 is provided independently from the gas line 20. ing.

As mentioned above, when the gas line 20 is used as the gas supply line 20F, the gas discharge line 20E, and the gas circulation line 20R, the carbon dioxide gas G flowing through the fifth pipe section 25 is on the upstream side of the compressor 30. It can be heated by the heating section 40. The heating unit 40 may heat the carbon dioxide gas G at all times, but in this embodiment, the heating unit 40 performs heating according to the temperature of the carbon dioxide gas G on the upstream side of the compressor 30. The operation of the heating section 40 is controlled by a control device 50.

(Hardware configuration diagram)
FIG. 6 is a diagram showing a hardware configuration of a control device provided in a floating body according to an embodiment of the present disclosure.
As shown in FIG. 6, the control device 50 includes a CPU 51 (Central Processing Unit), a ROM 52 (Read Only Memory), a RAM 53 (Random Access Memory), a storage 54 such as an HDD (Hard Disk Drive), and a signal transmission/reception module 55. It's a computer. The signal transmitting/receiving module 55 receives a detected value signal from the sensor 45.

(Functional block diagram)
FIG. 7 is a functional block diagram of a control device provided in a floating body according to an embodiment of the present disclosure.
As shown in FIG. 7, in the control device 50, the CPU 51 executes a program stored in a storage 54 such as an HDD, thereby realizing the functional configurations of a signal receiving section 71, a heating control section 72, and an output section 73. .
The signal receiving section 71 receives a detected value signal from the sensor 45 via the signal transmitting/receiving module 55 .

The heating control section 72 controls the operation of the heating section 40 based on the detected value of the sensor 45. The heating control section 72 controls the operation and stopping of the heating section 40 . The heating control section 72 operates the heating section 40 when the temperature of the carbon dioxide gas G flowing through the fifth pipe section 25, which is detected by the sensor 45, is lower than a predetermined lower limit threshold. The heating control section 72 stops the operation of the heating section 40 when the temperature of the carbon dioxide gas G flowing through the fifth pipe section 25 detected by the sensor 45 is higher than a predetermined upper limit threshold. The heating control section 72 generates a control signal for controlling starting and stopping of the heating section 40 .
The output section 73 outputs the control signal generated by the heating control section 72 to the heating section 40 via the signal transmission/reception module 55.

Furthermore, the control device 50 may control the opening and closing of the on-off valves 21v to 25v and 25w and the operation of the compressor 30. On the other hand, the opening and closing of the on-off valves 21v to 25v and 25w and the operation and stopping of the compressor 30 may be performed manually by remote control by an operator or the like.

(Steps for gas pressure control method)
Next, a gas pressure management method S10 in the ship 1 as described above will be explained.
FIG. 8 is a flowchart illustrating the procedure of a method for managing gas pressure in a floating body according to an embodiment of the present disclosure.
As shown in FIG. 8, the gas pressure management method S10 in this embodiment includes a step S11 of detecting the temperature of the carbon dioxide gas G, and a step of determining whether the temperature of the carbon dioxide gas G is below the lower limit threshold. S12, a step S13 of heating the carbon dioxide gas G, a step S14 of determining whether the temperature of the carbon dioxide gas G is equal to or higher than the upper limit threshold, and a step S15 of stopping the heating of the carbon dioxide gas G. include.

In step S11 of detecting the temperature of the carbon dioxide gas G, the sensor 45 detects the temperature of the carbon dioxide gas G flowing through the fifth pipe section 25 of the gas line 20 in a preset cycle, and calculates the detected value. The signal is output to the control device 50. The detected value signal output from this sensor 45 is received by the signal receiving section 71 of the control device 50.

In step S12 of determining whether the temperature of the carbon dioxide gas G is equal to or lower than the lower limit threshold, the heating control unit 72 determines whether the temperature of the carbon dioxide gas G indicated by the detected value of the sensor 45 is equal to or lower than a predetermined lower limit threshold. Determine whether the following is true.
As a result of this determination, if the temperature of the carbon dioxide gas G is equal to or lower than the lower limit threshold, the process proceeds to step S13 of heating the carbon dioxide gas G. On the other hand, if the temperature of the carbon dioxide gas G is not below the lower limit threshold, the process proceeds to step S14 in which it is determined whether the temperature of the carbon dioxide gas G is above the upper limit threshold.

In step S13 of heating the carbon dioxide gas G, the heating control section 72 operates the heating section 40. Thereby, the carbon dioxide gas G that has flowed into the heating section 40 from the fifth pipe section 25 is heated and flows out to the sixth pipe section 26 on the upstream side (in other words, the inlet side) of the compressor 30.

In step S14 of determining whether the temperature of carbon dioxide gas G is equal to or higher than the upper limit threshold, it is determined whether the temperature of carbon dioxide gas G is equal to or higher than a predetermined upper limit threshold.
As a result of this determination, if the temperature of the carbon dioxide gas G is equal to or higher than the upper limit threshold, the process proceeds to step S15 in which heating of the carbon dioxide gas G is stopped. On the other hand, if the temperature of the carbon dioxide gas G is not equal to or higher than the upper limit threshold, the process returns to step S11 of detecting the temperature of the carbon dioxide gas G described above, and the series of processes described above are repeated.

In step S15 of stopping the heating of the carbon dioxide gas G, the heating control unit 72 stops the operation of the heating unit 40. Thereby, heating of the carbon dioxide gas G by the heating unit 40 is stopped on the upstream side of the compressor 30.

(effect)
In the ship 1 of the embodiment described above, the gas line 20 is provided with the heating section 40 and the compressor 30. Thereby, the carbon dioxide gas G passing through the gas line 20 is heated by the heating unit 40 and then compressed by the compressor 30. In this way, since the temperature of the carbon dioxide gas G introduced into the compressor 30 has increased, it is possible to suppress the generation of dry ice at the inlet of the compressor 30 of the gas line 20 and the like.
In addition, by heating the carbon dioxide gas G in the heating section 40, in the gas line 20, on the downstream side of the heating section 40, the piping constituting the gas line 20 is not a piping with a low temperature specification, but a pipe with a higher temperature. Piping that is used under high conditions, for example, piping that is designed for room temperature, can be used. Specifically, the parts on the downstream side of the heating section 40, the sixth pipe part 26, the second pipe part 22, and the third pipe part 23, can be formed of piping used under higher temperature conditions. . Thereby, the cost of the gas line 20 can be reduced.

Furthermore, in the embodiment described above, the compressor 30 and the heating section 40 are provided in the gas exhaust line 20E. As a result, when the carbon dioxide gas G in the tank 11 is discharged to the outside of the tank 11, dry ice is generated at the inlet of the compressor 30 by heating the carbon dioxide gas G on the upstream side of the compressor 30. can be suppressed.

Similarly, in the above embodiment, the compressor 30 and the heating section 40 are provided in the gas supply line 20F. Thereby, when discharging the carbon dioxide gas G into the tank 11, the carbon dioxide gas G can be heated upstream of the compressor 30. Therefore, it is possible to suppress the generation of dry ice at the inlet of the compressor 30 and the like.

Furthermore, in the embodiment described above, the compressor 30 and the heating section 40 are provided in the gas circulation line 20R. Thereby, when the carbon dioxide gas G in the tank 11 is taken out of the tank 11 through the gas circulation line 20R and then circulated into the tank 11, the carbon dioxide gas G is heated on the upstream side of the compressor 30. be able to. Therefore, it is possible to suppress the generation of dry ice at the inlet of the compressor 30 and the like.

In the above embodiment, the compressor 30 and the heating section 40 are provided between the fifth pipe section 25 and the sixth pipe section 26, which are shared by the gas discharge line 20E, the gas supply line 20F, and the gas circulation line 20R. Therefore, compared to the case where the compressor 30 and the heating section 40 are individually provided in the gas discharge line 20E, the gas supply line 20F, and the gas circulation line 20R, the number of the compressor 30 and the heating section 40 can be reduced. . As a result, it is possible to suppress an increase in the number of parts and improve the degree of freedom in arrangement.

Further, the ship 1 of the embodiment described above includes a sensor 45 and a heating control section 72.
Thereby, the temperature of the carbon dioxide gas G on the inlet side of the compressor 30 can be detected. Then, when the temperature detected by the sensor 45 is below a predetermined lower limit threshold, the carbon dioxide gas G can be heated. generation can be effectively suppressed.

Further, according to the gas pressure management method S10 of the above embodiment, when the temperature of the carbon dioxide gas G at the inlet side of the compressor 30 is below a predetermined lower limit threshold, the carbon dioxide gas G is heated. There is. As a result, the temperature of the carbon dioxide gas G introduced into the compressor 30 can be raised above the lower limit threshold, thereby effectively suppressing the formation of dry ice on the inlet side of the compressor 30 of the gas line 20, etc. Can be done.

(Other embodiments)
Although the embodiment of the present disclosure has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes design changes within the scope of the gist of the present disclosure. .
For example, in the above-described embodiment, the ship 1 is used as an example of the floating body, but it may be a floating body such as a floating storage unit (FSU) or a floating storage and regasification unit (FSRU).

Further, in the above embodiment, the carbon dioxide gas G is heated when the temperature of the carbon dioxide gas G on the inlet side of the compressor 30 is below the lower limit threshold, but the present invention is not limited to this. For example, the heating unit 40 may always heat the carbon dioxide gas G when the compressor 30 compresses the carbon dioxide gas G.

Furthermore, in the above embodiment, the gas line 20 is configured to include the gas exhaust line 20E, the gas supply line 20F, and the gas circulation line 20R, but the configuration is not limited to this. The gas discharge line 20E, the gas supply line 20F, and the gas circulation line 20R may be provided individually. In that case, the compressor 30 and the heating section 40 may be provided in each of the gas discharge line 20E, the gas supply line 20F, and the gas circulation line 20R. Further, the compressor 30 and the heating section 40 may be provided only in part of the gas discharge line 20E, the gas supply line 20F, and the gas circulation line 20R.

Furthermore, in the above embodiment, when the carbon dioxide gas G is passed through the gas line 20, the carbon dioxide gas G always passes through the heating section 40 and the compressor 30, but the configuration is not limited thereto. For example, a bypass line that bypasses the heating unit 40 and the compressor 30 may be provided, and when the compressor 30 does not compress the carbon dioxide gas G, the carbon dioxide gas G may be passed through the bypass line.

<Additional notes>
The floating body 1 and gas pressure management method S10 described in the embodiment can be understood, for example, as follows.

(1) The floating body 1 according to the first aspect includes a floating body body 2, a tank 11 provided in the floating body body 2 and capable of storing liquefied carbon dioxide L, and a tank 11 that stores the liquefied carbon dioxide L in the tank 11. A supply line 15 that can be supplied, a discharge line 16 that discharges the liquefied carbon dioxide L in the tank 11 to the outside of the tank 11, and a gas line 20 that is connected to the tank 11 and allows carbon dioxide gas G to flow therethrough. , a compressor 30 provided in the gas line 20, and a heating unit 40 provided upstream of the compressor 30 in the gas line 20 and capable of heating the carbon dioxide gas G flowing through the gas line 20. and.
Examples of the floating body 1 include a ship and offshore floating equipment. Examples of the floating body 2 include a ship hull and a floating body of offshore floating equipment.

In the floating body 1 having such a configuration, the liquefied carbon dioxide L is supplied into the tank 11 through the supply line 15. As liquefied carbon dioxide L is supplied into tank 11 , carbon dioxide gas G forming a gas phase within tank 11 is pushed out of tank 11 through gas line 20 .
Further, liquid carbon dioxide in the tank 11 can be discharged to the outside of the tank 11 through the discharge line 16. As the liquid carbon dioxide in the tank 11 is discharged, carbon dioxide gas G is introduced into the tank 11 from outside the tank 11 through the gas line 20.
The gas line 20 is provided with a heating section 40 and a compressor 30. Carbon dioxide gas G passing through the gas line 20 is heated by the heating unit 40 and then compressed by the compressor 30. In this way, since the temperature of the carbon dioxide gas G introduced into the compressor 30 has increased, it is possible to suppress the generation of dry ice at the inlet of the compressor 30 of the gas line 20 and the like.
In addition, by heating the carbon dioxide gas G in the heating section 40, on the downstream side of the heating section 40 of the gas line 20, the piping constituting the gas line 20 is not a pipe with a low temperature specification, but a pipe with a normal temperature specification, etc. can be adopted. Specifically, the portions on the downstream side of the heating section 40, the sixth tube section 26, the second tube section 22, and the third tube section 23, can be formed by pipes rated at room temperature. Thereby, the cost of the gas line 20 can be reduced.

(2) The floating body 1 according to the second aspect is the floating body 1 of (1), wherein the gas line 20 is a gas discharge line that discharges the carbon dioxide gas G in the tank 11 to the outside of the tank 11. 20E, the compressor 30 and the heating section 40 are provided in the gas discharge line 20E.

As a result, when the carbon dioxide gas G in the tank 11 is discharged to the outside of the tank 11, dry ice is generated at the inlet of the compressor 30 by heating the carbon dioxide gas G on the upstream side of the compressor 30. can be suppressed.

(3) The floating body 1 according to the third aspect is the floating body 1 of (1) or (2), in which the gas line 20 supplies the carbon dioxide gas G from outside the tank 11 into the tank 11. The compressor 30 and the heating section 40 are provided in the gas supply line 20F.

Thereby, when discharging the carbon dioxide gas G into the tank 11, the carbon dioxide gas G can be heated upstream of the compressor 30. Therefore, it is possible to suppress the generation of dry ice at the inlet of the compressor 30 and the like.

(4) The floating body 1 according to the fourth aspect is the floating body 1 according to any one of (1) to (3), in which the gas line 20 connects the carbon dioxide gas G in the tank 11 to the tank 1. The heating section 40 and the compressor 30 are provided in the gas circulation line 20R.

Thereby, when the carbon dioxide gas G in the tank 11 is taken out of the tank 11 through the gas circulation line 20R and then circulated into the tank 11, the carbon dioxide gas G is heated on the upstream side of the compressor 30. be able to. Therefore, it is possible to suppress the generation of dry ice at the inlet of the compressor 30 and the like.

(5) The floating body 1 according to the fifth aspect is the floating body 1 according to any one of (1) to (4), and is a sensor that detects the temperature of the carbon dioxide gas G on the inlet side of the compressor 30. 45, and a heating control unit 72 that heats the carbon dioxide gas G when the detected temperature is below a predetermined lower limit threshold.

According to such a configuration, when the temperature detected by the sensor 45 is below a predetermined lower limit threshold, the carbon dioxide gas G can be heated, so that the inlet of the compressor 30 of the gas line 20 It is possible to effectively suppress the formation of dry ice on the sides and the like.

(6) The gas pressure management method S10 according to the sixth aspect is a gas pressure management method S10 in the floating body 1 according to any one of (1) to (5), and includes carbon dioxide flowing through the gas line 20. A step S11 of detecting the temperature of the carbon dioxide gas G, a step S12 of determining whether the detected temperature of the carbon dioxide gas G is below a predetermined lower limit threshold, and a step S12 of determining whether the temperature of the carbon dioxide gas G If it is determined that the carbon dioxide gas G flowing through the gas line 20 is heated by the heating section 40, the step S13 is included.

According to such a configuration, when the temperature of the carbon dioxide gas G at the inlet side of the compressor 30 is below a predetermined lower limit threshold, the carbon dioxide gas G can be heated. The temperature of the carbon dioxide gas G introduced into the carbon dioxide gas can be raised above the lower limit threshold. Therefore, the generation of dry ice can be effectively suppressed on the inlet side of the compressor 30 of the gas line 20 and the like.

According to the floating body and gas pressure control method of the present disclosure, generation of dry ice can be suppressed.

1... Vessel (floating body) 2... Hull (floating body body) 2a... Bow 2b... Stern 3A, 3B... Broad side 5... Upper deck 7... Upper structure 8... Cargo loading compartment 10... Tank equipment 11... Tank 11t... Top 12... Cylinder Shape portion 13...End plate part 15...Supply line 15a...Tip 16...Discharge line 16a...Tip 18...Pump 20...Gas line 20E...Gas discharge line 20F...Gas supply line 20R...Gas circulation line 21...First pipe part 21a... One end 21b...Other end 21v...On-off valve 22...Second pipe section 22a...One end 22b...Other end 22v...On-off valve 23...Third pipe section 23a...One end 23b...Other end 23v...On-off valve 24...Fourth pipe section 24a ...One end 24b...Other end 24v...On-off valve 25...Fifth pipe section 25a...One end 25b... Other end 25v, 25w...On-off valve 30...Compressor 40...Heating part 45...Sensor 50...Control device 51...CPU 52...ROM 53...RAM 54...Storage 55...Signal transmission/reception module 71...Signal receiving unit 72...Heating control unit 73...Output unit Da...Fore and aft direction Dv...Vertical direction Dx...Longitudinal direction G...Carbon dioxide gas L...Liquefied carbon dioxide S10... Gas pressure management method S11... Step of detecting the temperature of carbon dioxide gas S12... Step of determining whether the temperature of carbon dioxide gas is below the lower limit threshold S13... Step of heating carbon dioxide gas S14... Step of heating carbon dioxide gas Step of determining whether the temperature is equal to or higher than the upper limit threshold S15...Step of stopping heating of carbon dioxide gas

Claims (6)

1. A floating body,
   a tank provided on the floating body body and capable of storing liquefied carbon dioxide;
   a supply line that supplies the liquefied carbon dioxide into the tank;
   a discharge line for discharging the liquefied carbon dioxide in the tank to the outside of the tank;
   a gas line connected to the tank and through which carbon dioxide gas can flow;
   a compressor that is provided in the gas line and compresses the carbon dioxide gas flowing through the gas line;
   a heating section that is provided upstream of the compressor in the gas line and is capable of heating the carbon dioxide gas flowing through the gas line;
   A floating body equipped with
2. The gas line includes a gas discharge line that discharges the carbon dioxide gas in the tank to the outside of the tank,
   The floating body according to claim 1, wherein the compressor and the heating section are provided in the gas discharge line.
3. The gas line includes a gas supply line that supplies the carbon dioxide gas from outside the tank into the tank,
   The floating body according to claim 1 or 2, wherein the compressor and the heating section are provided in the gas supply line.
4. The gas line includes a gas circulation line that takes the carbon dioxide gas in the tank out of the tank and returns it into the tank,
   The floating body according to claim 1 or 2, wherein the heating section and the compressor are provided in the gas circulation line.
5. a sensor that detects the temperature of the carbon dioxide gas on the inlet side of the compressor;
   The floating body according to claim 1 or 2, further comprising a heating control unit that heats the carbon dioxide gas when the detected temperature is below a predetermined lower limit threshold.
6. A gas pressure management method in a floating body according to claim 1 or 2, comprising:
   detecting the temperature of carbon dioxide gas flowing through the gas line;
   determining whether the temperature of the detected carbon dioxide gas is below a predetermined lower threshold;
   A gas pressure management method including the step of heating the carbon dioxide gas flowing through the gas line in the heating section when it is determined that the temperature of the carbon dioxide gas is equal to or lower than the lower limit threshold.

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