JP2012002159A - Transport means with carbon dioxide recovering function and method of recovering carbon dioxide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transport means equipped with carbon dioxide recovering function and a method of recovering carbon dioxide to prevent a problem caused by the recovered carbon dioxide, such as an operation failure to be caused by unbalanced weight or capacity of the transport means.SOLUTION: The transport means equipped with carbon dioxide recovering function includes an internal tank 1B to store a hydrocarbon-based fuel and carbon dioxide, a tank pressure sensor 17 to detect a pressure, a tank pressure regulator 18 to regulate the pressure on the basis of the detection result, a tank temperature sensor 19 to sense the temperature, a tank temperature adjuster 20 to adjust the temperature of the internal tank 1B on the basis of the detection result, a shell tank temperature sensor 15 to sense the temperature of a shell tank 1A covering the outside of the internal tank 1B, and a shell tank cooler 16 to cool the shell tank 1A on the basis of the detection result. By using the above apparatuses, the transport means controls the conditions for storing the hydrocarbon-based fuel and carbon dioxide in the tank 1B.

Description

  The present invention relates to a transportation means with a carbon dioxide recovery function for separating and recovering carbon dioxide released from transportation means such as a ship in order to reduce greenhouse gas (Greenhouse Gas, hereinafter referred to as “GHG”) emission amount. The present invention relates to a carbon dioxide recovery processing method for processing recovered carbon dioxide in the ocean.

Reducing GHG emissions is an internationally important issue to be solved for the time being. The amount of GHG released from ships all over the world in 2007 accounted for 3.3% of the total global GHG emissions (IMO Marine Environment Protection Committee, 2009). Corresponds to emissions.
The International Maritime Organization (hereinafter referred to as “IMO”) is the GHG released from ships in response to requests from the Intergovernmental Panel on Climate Change (hereinafter referred to as “IPCC”). We are investigating ways to dramatically reduce this. This is because, in order to dramatically reduce GHG, in addition to reducing the frictional force around the hull and improving engine efficiency, other new ideas are required. A new idea is to use a high-efficiency storage battery to propel the ship, but such a high-efficiency storage battery system is not readily available at this time.
A promising option other than the above idea is to burn fuel in oxygen. This method can easily separate carbon dioxide and water by cooling the combusted exhaust gas and does not require any newly developed technology. Expected as an alternative. In this method of burning fuel in oxygen, proper fuel, oxygen supply, appropriate engine system, balance between engine and energy, on-board system to capture and store carbon dioxide, transfer of liquefied carbon dioxide to the ocean ( CCS, Carbon Capture and Storage) and cost assessment are important factors.

The above-described method of burning fuel in oxygen, more specifically, the method of separating carbon dioxide from water and carbon dioxide generated when fuel is burned in oxygen has been conventionally performed. (For example, Patent Documents 1 to 3).
Patent Document 1 discloses a large-scale movement system such as a train or a ship that recovers carbon dioxide generated by burning hydrocarbon fuel with pure oxygen. Patent Document 2 discloses a system for recovering carbon dioxide produced by mixing and burning a hydrocarbon fuel with oxygen. However, Patent Documents 1 and 2 do not describe anything about controlling storage conditions when collecting and storing carbon dioxide.
In Patent Document 3, after separating water from oxygen-rich air from which at least a part of nitrogen is removed from air and a combustion product containing water and carbon dioxide generated by burning fuel, carbon dioxide is liquefied. Vehicles for transportation such as automobiles, trucks, trains, airplanes, and ships that are accumulated in the past are disclosed. However, this document also does not describe any control of storage conditions when storing the recovered carbon dioxide.
Further, Patent Document 4 does not relate to burning fuel using pure oxygen, but there is a technique in which carbon dioxide generated when fuel burns is liquefied by heat exchange with low-temperature LNG. Are listed. However, like the above Patent Documents 1 to 3, the same document does not describe any control of storage conditions when collecting and storing carbon dioxide.

Japanese National Patent Publication No. 10-505145 Japanese Patent Laid-Open No. 11-72009 Japanese translation of PCT publication No. 2002-503782 Japanese Patent No. 2898092

In order to reduce the amount of GHG emitted by the means of transport, when recovering carbon dioxide generated when burning stored fuel without releasing it into the air, first the fuel and recovered carbon dioxide should be stored under appropriate storage conditions. Need to manage. In addition, the storage capacity and balance of the transportation means change due to the supply of fuel and the recovered carbon dioxide. Changes in the storage capacity and balance of the transportation means due to this fuel supply and recovered carbon dioxide may interfere with the operation of the transportation means. For example, there is a possibility that a situation in which the ship loses balance and leans to one side adversely affects propulsion efficiency. There is also a problem of how to treat the carbon dioxide collected by the transportation means.
It is an object of the present invention to prevent the occurrence of problems caused by storage of stored fuel and recovered carbon dioxide, and problems that hinder the operation of transportation means due to the loss of balance of weight and capacity. Yes. Moreover, it aims at appropriately transporting and storing the recovered carbon dioxide as a transportation means.

The transport means with a carbon dioxide recovery function according to the first aspect of the present invention uses a drive means, a fuel storage means for storing hydrocarbon fuel, a hydrocarbon fuel and oxygen supplied from the fuel storage means. Energy conversion means for extracting energy, carbon dioxide processing means for processing the carbon dioxide in the exhaust gas discharged from the energy conversion means into a storable state, and recovering the carbon dioxide processed by the carbon dioxide processing means And carbon dioxide storage means for storing, and storage condition control means for controlling storage conditions of the fuel storage means and the carbon dioxide storage means.
Here, “transportation means” means means for transporting people and cargo, for example, ships, cars, trains, and the like. “Hydrocarbon fuel” refers to a fuel of a compound composed of carbon and hydrogen, for example, petroleum products such as methane, ethane, propane, natural gas, alcohols, light oil, heavy oil, gasoline, and the like. “Energy conversion means” refers to means for converting chemical energy, thermal energy, electric energy, etc. of hydrocarbon fuel into energy suitable for transportation means, such as engines and turbines. This includes a fuel cell having a boiler and reforming means as well as a heat engine. Further, the “carbon dioxide treatment means” means a means for treating carbon dioxide so that it can be stored, for example, means for cooling and / or pressurizing carbon dioxide.
“Controlling storage conditions” means, for example, appropriately controlling temperature, pressure, etc., which are physical conditions for storage of fuel storage means, carbon dioxide storage means, hydrocarbon fuel and recovered carbon dioxide Control to reduce the effect of weight balance and capacity balance disruption due to differences in density and capacity, control storage according to the form and shape of fuel storage means and carbon dioxide storage means, and placement conditions, etc. Say.
With this configuration, the carbon dioxide generated from the hydrocarbon fuel and oxygen supplied from the fuel storage means mounted on the transportation means is stored in the carbon dioxide storage means mounted on the transportation means under controlled storage conditions. .

According to a second aspect of the present invention, in the transport means with a carbon dioxide recovery function according to the first aspect, the storage condition control means controls the temperature of the fuel storage means and / or the carbon dioxide storage means. It is characterized by that.
With this configuration, the temperature as the storage condition of the fuel storage means and / or the carbon dioxide storage means is controlled.

According to a third aspect of the present invention, in the transport means with a carbon dioxide recovery function according to the first or second aspect, the hydrocarbon fuel has ethane or ethane as a main component and a saturation temperature equal to or higher than ethane. It is a mixture with a hydrocarbon.
Here, the “main component” means a component occupying the largest volume among the components contained in the mixture. Examples of the “hydrocarbon having a saturation temperature higher than ethane” include propane, propylene, butane and the like. In addition, “the mixture of the main component ethane and hydrocarbons with a saturation temperature higher than ethane” includes ethane fuel mixed with butane and propane with saturation temperatures higher than ethane extracted from natural gas. It is.
With this configuration, the hydrocarbon fuel can be handled in a liquid state, for example, by setting the fuel storage means to the ethane saturation temperature or lower.

According to a fourth aspect of the present invention, in the transport means with a carbon dioxide recovery function according to the third aspect, the fuel storage means also serves as the carbon dioxide storage means.
With this configuration, the fuel storage means can be configured as the same storage means as the carbon dioxide storage means.

According to a fifth aspect of the present invention, in the transport means with a carbon dioxide recovery function according to one of the first to fourth aspects, the fuel storage means and the carbon dioxide storage means are the transport means. It is characterized by being arranged in a weight balance with respect to the above.
Here, “arranged in a weight balance with respect to the transportation means” means a position that does not hinder transportation or work due to non-uniform weight of the fuel storage means and the carbon dioxide storage means, It means that these are arranged in the moment relation.
With this configuration, it is possible to eliminate the loss of weight balance that causes troubles in transportation and work as fuel is supplied and carbon dioxide is recovered.

According to a sixth aspect of the present invention, in the transport means with a carbon dioxide recovery function according to one of the first to fifth aspects, the storage condition control means has a weight and / or capacity balance. It is characterized by controlling the storage conditions of the fuel storage means and the carbon dioxide storage means.
Here, “weight and / or capacity balance can be achieved” means the influence of the balance of weight and capacity balance caused by the difference in density and capacity between hydrocarbon fuel and recovered carbon dioxide. It can be reduced. For example, it means preventing troubles in transportation and work by the transportation means due to imbalance in the weight and / or capacity of the fuel in the fuel storage means and the carbon dioxide in the carbon dioxide storage means. In addition, “the storage condition control means controls the storage conditions of the fuel storage means and the carbon dioxide storage means so that a balance between weight and / or capacity” can be achieved. Fuel and / or carbon dioxide is stored so that the weight balance and / or capacity balance of the left and right of the shaft is maintained when viewed in the bow direction when the transportation means is divided into two equal parts by an axis parallel to the traveling direction. That means.
With this configuration, the storage condition control means controls the balance between weight and / or capacity as fuel is supplied and carbon dioxide is recovered, so that troubles in transportation and work can be reduced from the control aspect. .

According to a seventh aspect of the present invention, in the transport means with a carbon dioxide recovery function according to one of the first to sixth aspects, the carbon dioxide treatment means is stored in a liquefied state in the fuel storage means. It is characterized in that it includes a cold heat exchange means provided in a path for supplying the obtained hydrocarbon fuel to the energy conversion means.
With this configuration, it is possible to use the cold heat of the hydrocarbon fuel stored in the liquefied state for the carbon dioxide treatment.
The present invention according to claim 8 is the transport means with a carbon dioxide recovery function according to one of claims 1 to 7, further comprising an oxygen separation means for extracting oxygen from the atmosphere supplying the oxygen. It is characterized by being provided.
With this configuration, part or all of oxygen used for energy conversion of the hydrocarbon fuel can be supplied from the oxygen separation means.
The invention according to claim 9 is the water addition for adding water when performing energy conversion by the energy conversion means in the transport means with carbon dioxide recovery function according to one of claims 1 to 8 The apparatus further comprises means.
With this configuration, it is possible to control conversion conditions when energy conversion is performed using water added from the water addition unit.
A tenth aspect of the present invention is the transport means with a carbon dioxide recovery function according to one of the first to ninth aspects, further comprising a carbon dioxide extraction means for extracting carbon dioxide from the exhaust gas. It is characterized by that.
With this configuration, for example, water can be removed from the exhaust gas using the carbon dioxide extraction means.

The present invention described in claim 11 is characterized in that in the transport means with a carbon dioxide recovery function according to one of claims 1 to 10, the transport means is a ship.
With this configuration, carbon dioxide can be recovered from the hydrocarbon-based fuel used in the ship and recovered in the carbon dioxide storage means mounted on the ship.
According to a twelfth aspect of the present invention, in the transport means with a carbon dioxide recovery function according to one of the first to eleventh aspects, the hydrocarbon fuel is also a transport target fuel of the transport means. It is characterized by that.
With this configuration, it becomes possible to supply the fuel to be transported by the transportation means to the energy conversion means.

According to a thirteenth aspect of the present invention, there is provided a carbon dioxide recovery processing method using the transport means with a carbon dioxide recovery function according to one of the first to twelfth aspects of the invention to recover the carbon dioxide storage means. The stored carbon dioxide is transported to a predetermined location.
With this configuration, the carbon dioxide recovered in the carbon dioxide storage means and stored on the transportation means can be transported to a predetermined place by the transportation means itself.
According to a fourteenth aspect of the present invention, in the carbon dioxide recovery processing method according to the thirteenth aspect, the transportation means is a ship, and the carbon dioxide transported to the predetermined location is transported underwater or under the seabed. It is a thing to store.
With this configuration, it is possible to transport the carbon dioxide collected by a ship to a predetermined place and transport it underwater or under the seabed.
According to a fifteenth aspect of the present invention, in the carbon dioxide recovery processing method according to the fourteenth aspect, when the carbon dioxide is stored in the sea or under the seabed, the carbon dioxide is transferred to the sea or under the seabed. It is characterized in that weight balance control is performed in cooperation with the ship's ballast water-filled drainage system.
With this configuration, when carbon dioxide is transferred into the sea or below the seabed, it is possible to achieve a weight balance in cooperation with the ballast hydrostatic drainage system of the ship.

The transport means with a carbon dioxide recovery function of the present invention includes a storage condition control means for controlling the storage conditions of the fuel storage means and the carbon dioxide storage means. By this storage condition control means, temperature, pressure, etc., which are physical conditions in storage of the fuel storage means and the carbon dioxide storage means, can be appropriately controlled. In addition, it is possible to control to reduce the influence of the weight balance and capacity balance collapse due to the difference in density and capacity between the hydrocarbon fuel and the recovered carbon dioxide. For example, by controlling the storage conditions of hydrocarbon fuel and carbon dioxide so that the balance of the transportation means is not lost, it is possible to prevent the occurrence of problems such as hindering the operation of the transportation means. Furthermore, storage control according to the form and shape of the fuel storage means and the carbon dioxide storage means and the arrangement conditions can be performed.
Moreover, the storage condition control means can control the phase transition of the hydrocarbon fuel and carbon dioxide by controlling the temperature, and for example, both can be maintained in the liquid phase.
Further, if ethane is used as the hydrocarbon-based fuel, it can be stored under substantially the same storage conditions since the physical conditions for storage are close to those of carbon dioxide. For example, the fuel storage means can also serve as the carbon dioxide storage means. Thereby, since carbon dioxide can be stored using the space of the fuel storage means after ethane is supplied, it is possible to effectively use the space on the transport means.
Further, if the fuel storage means and the carbon dioxide storage means are arranged in a weighted balance with respect to the transportation means, troubles in transportation, work, etc. due to these weight imbalances occur. Can be prevented.
In addition, if the storage conditions of the fuel storage means and the carbon dioxide storage means are controlled so that a weight and / or capacity balance can be achieved by the storage condition control means, It is possible to prevent the balance of transportation means from being lost.
Further, if the carbon dioxide treatment means includes a cold heat exchange means provided in a path for supplying the hydrocarbon fuel stored in the liquefied state to the energy conversion means, carbon dioxide is generated by the cold heat of the hydrocarbon fuel. It can be cooled and liquefied.
Further, if the oxygen separation means is provided, the oxygen separation means extracts rich oxygen from the atmosphere and burns hydrocarbon fuel in the rich oxygen to produce only water and carbon dioxide as exhaust gas. be able to. Thereby, since water can be removed by cooling the exhaust gas with the carbon dioxide extraction means, it becomes easy to extract carbon dioxide from the exhaust gas.
Moreover, if it is set as the structure provided with the water addition means, when performing energy conversion, water can be added and combustion temperature can be lowered | hung. For this reason, even when a hydrocarbon fuel is burned in pure oxygen, the combustion temperature can be set in accordance with the heat resistance performance of the apparatus constituting the energy conversion means. This makes it possible to use a device that is currently used normally as the energy conversion means.

Even when the transportation means is a ship, the storage condition control means controls the storage conditions of the fuel storage means and the carbon dioxide storage means, thereby preventing the balance from being lost and resulting from the recovered carbon dioxide. Due to the loss of balance, it is possible to prevent the occurrence of a situation such as a decrease in propulsion efficiency, a hindrance to work on the ship, and inability to operate.
In addition, when the transportation means is a ship and the fuel is intended for transportation, if the transportation target fuel is used as a hydrocarbon-based fuel, the transportation means fuel storage means can also be used as the fuel storage means. This eliminates the need for a separate fuel storage means.

The carbon dioxide recovery processing method of the present invention transports the carbon dioxide recovered and stored in the carbon dioxide storage means to a predetermined place using the transport means with carbon dioxide recovery function described above. For this reason, the carbon dioxide collected by the transportation means itself can be transported to a predetermined place, and another transportation means is not required. Further, it is possible to prevent a problem that the transportation means loses balance due to the recovered carbon dioxide.
In addition, if the transport means is a ship and the carbon dioxide transported to a predetermined location is transported and stored in the sea or below the seabed, the carbon dioxide can be stored in the sea or below the seafloor with a large room for storage. This is effective in reducing GHG.
In addition, if carbon dioxide is transferred underwater or under the seabed, weight balance control should be performed in conjunction with the ship's ballast hydrostatic drainage system. Can be prevented from being disturbed by losing balance.

Functional block diagram for storage condition control of ethane / carbon dioxide tank Functional block diagram of a carbon dioxide sequestration ship which is a transportation means of the first embodiment Explanatory drawing explaining the structure of the ethane / carbon dioxide tank with which the carbon dioxide isolation ship of Embodiment 1 is equipped Graph showing the relationship between carbon dioxide and hydrocarbon pressure and saturation temperature Perspective view showing the outline of the loading state of the ethane / carbon dioxide tank on the carbon dioxide sequestration ship Schematic diagram showing schematic configuration of ethane / carbon dioxide tank Schematic diagram showing ethane supply and carbon dioxide storage of ethane / carbon dioxide tank during navigation of carbon dioxide sequestration ship Schematic diagram schematically showing the extraction of carbon dioxide from an ethane / carbon dioxide tank during carbon dioxide sequestration on a carbon dioxide sequestration ship Schematic diagram schematically showing the supply of ethane to the ethane / carbon dioxide tank when storing ethane on a carbon dioxide sequestration ship Schematic showing another example that can be adopted as the configuration of ethane / carbon dioxide tank A perspective view schematically showing a carbon dioxide sequester ship that transports LNG (liquefied natural gas), which is a hydrocarbon-based fuel, as a transportation target. Schematic diagram explaining the outline of the carbon dioxide recovery processing method of Embodiment 2 of the present invention

(Embodiment 1)
The first embodiment of the present invention will be described below with reference to FIGS.
[Schematic configuration of carbon dioxide sequestration ship]
FIG. 2 is a functional block diagram of a carbon dioxide sequestration (zero emission) ship (transport means) 100 which is a transport means according to the first embodiment of the present invention. As shown in the figure, a carbon dioxide sequestering vessel 100 according to Embodiment 1 of the present invention includes an ethane / carbon dioxide tank (fuel storage means, carbon dioxide storage means) 1, an oxygen generator (oxygen separation means) 2, Gas turbine (energy conversion means) 3, steam generator 4, steam turbine (energy conversion means) 5, condenser 6, propeller motor (drive means) 7, exhaust gas cooler (carbon dioxide extraction means) 8, carbon dioxide / water Separator (carbon dioxide extraction means, water addition means) 9, carbon dioxide compressor (carbon dioxide treatment means) 10, carbon dioxide precooler (carbon dioxide treatment means) 11, carbon dioxide second cooler (carbon dioxide treatment means) ) 12, ethane / carbon dioxide cold heat exchanger (carbon dioxide treatment means, storage condition control means, cold heat exchange means) 13 and water supply pipe 14 (water addition means) . Below, each component of the carbon dioxide sequestration ship 100 is demonstrated.

  The ethane / carbon dioxide tank 1 has, for example, a configuration in which a plurality of internal tanks 1B are provided inside a cylindrical outer shell tank 1A as shown in FIGS. 3 (a) to 3 (c). 3 (a), (b) and (c) show an ethane / carbon dioxide tank 1 provided with 19, 7, and 3 internal tanks 1B in this order. 3 (a) to 3 (c) all show the state in which the upper diagram shows the ethane / carbon dioxide tank 1 inside the carbon dioxide sequestration vessel 100 as viewed from above, and the lower diagram shows The figure shows a state where one internal tank 1B inside the ethane / carbon dioxide tank 1 is taken out and viewed from the side in the same state. However, the configuration of the ethane / carbon dioxide tank 1 is not limited to this, and the number of internal tanks 1B provided in the outer shell tank 1A can be set as appropriate. In the following description, an example having seven internal tanks 1B in FIG.

The ethane / carbon dioxide tank 1 is used for storing ethane used as fuel and recovered carbon dioxide, and serves as both fuel storage means and carbon dioxide storage means. For this reason, the space created after the fuel in the ethane / carbon dioxide tank 1 is used is used to store the carbon dioxide recovered from the exhaust gas.
The carbon dioxide sequestration ship 100 according to the present embodiment uses ethane as a fuel. However, when all the carbon dioxide generated by burning ethane in oxygen is recovered, the carbon dioxide in the recovered liquid is recovered. Is 24% more in volume than the liquid ethane used as fuel. For this reason, if the capacity of the ethane / carbon dioxide tank 1 is 24% larger than the capacity of ethane used as fuel, all of the carbon dioxide generated by the combustion of ethane can be recovered and stored.
However, the capacity of the ethane / carbon dioxide tank 1 may be the same as the capacity of ethane used as fuel, and some of the carbon dioxide generated by ethane combustion may be released into the atmosphere without being recovered. As described above, even if a part of carbon dioxide generated by burning ethane in oxygen is released into the atmosphere, nearly 80% of the carbon dioxide generated by ethane combustion can be recovered. It is effective to reduce
In order to completely supply and consume ethane, which is the fuel in the ethane / carbon dioxide tank 1, a polymer membrane (polymer membrane) is used to separate ethane and carbon dioxide in the ethane / carbon dioxide tank 1. ) May be used.

The oxygen generator 2 includes five compressors (not shown). The five compressors first pressurize the air into oxygen-enriched air. And the oxygen content rate of the air rich in oxygen is made high by further repeatedly squeezing the air rich in oxygen obtained by pressing. Specifically, as the number of times of pressing increases, the oxygen content ratio in the obtained air becomes 0.4, 0.64, 0.84, 0.94, and finally by repeating the pressing five times, An oxygen content of 0.98 (concentrated oxygen) is obtained. In the oxygen generator 2, a high-efficiency axial flow compressor is used.
In supplying oxygen, the oxygen stored in the oxygen storage means can be supplied without the oxygen generator 2. Further, oxygen can be supplied by combining the oxygen generator 2 and the oxygen storage means. Furthermore, the oxygen storage means can be used as a carbon dioxide storage means. In the case of having these oxygen storage means, it is preferable to arrange and control storage in a weight-balance and capacity-balance manner, similarly to the fuel storage means and carbon dioxide storage means.

The gas turbine 3 includes a main body 3A having a combustor and a turbine, and a generator 3B. The turbine is rotated by exhaust gas generated by combustion in the combustor 3A to generate power by the generator 3B. Thus, electric power for driving the propeller motor 7 and electric power consumed in the carbon dioxide sequestration ship 100 are generated. The electric power consumed in the carbon dioxide sequestration ship 100 is for carbon capture and storage (hereinafter referred to as “CCS” where appropriate), such as taking out oxygen from the air by the oxygen generator 2. The necessary power is included.
High-temperature exhaust gas produced by combustion of oxygen supplied from the oxygen generator 2 and ethane supplied from the ethane / carbon dioxide tank 1 via the ethane / carbon dioxide cold heat exchanger 13 in the combustor of the main body 3A Rotates the turbine.
When ethane is burned in oxygen, the combustion produces only water and carbon dioxide, no nitrogen remains and no nitrogen oxides. From this, carbon dioxide can be easily separated and recovered by cooling the exhaust gas generated by combustion. Thereby, it becomes possible to reduce the separation and recovery cost of carbon dioxide, which is a problem in CCS. Further, by burning in oxygen (oxygen combustion), the combustion temperature becomes higher than in air (air combustion). Specifically, the temperature becomes close to about 2000 ° C. by oxyfuel combustion, which is several hundred degrees C. higher than air combustion. Since the thermal efficiency becomes high in a high temperature range, the oxyfuel combustion can be expected to recover unused energy that could not be used conventionally.

However, since a material that can withstand a high temperature is very limited, a special development and design for the gas turbine 3 are required.
In the carbon dioxide sequestering vessel 100 of the first embodiment, the temperature is obtained by adding water before oxygen and ethane are supplied into the gas turbine 3 so that the gas turbine 3 that is currently used normally can be used. Is adjusted to a temperature corresponding to the heat resistance of the turbine of the main body 3A. More specifically, the water separated by the carbon dioxide / water separator 9 is added to the mixture of oxygen and ethane before being supplied to the gas turbine 3 through the water supply pipe 14, thereby exhaust gas. The temperature is lowered.
Usually, the temperature of the exhaust gas discharged from the gas turbine 3 is still sufficient to produce steam. Therefore, heat is exchanged by the steam generator 4 to generate steam, and this steam is sent to the steam turbine 5 to generate power by the steam turbine 5.
It is also possible to collect and recycle and add carbon dioxide generated together with water, or to add only carbon dioxide to lower the temperature of exhaust gas or to suppress the generation of nitrogen oxides. is there.

  The steam turbine 5 includes a main body 5 </ b> A having a turbine and a generator 5 </ b> B, and generates power by rotating the turbine of the main body 5 </ b> A by the flow of water vapor from the steam generator 4. The steam used for power generation in the steam turbine 5 is sent to the condenser 6.

  The condenser 6 cools and condenses the water vapor sent from the steam turbine 5 with seawater to form water. The water cooled and condensed here is sent again to the steam generator 4 and converted into steam by the heat exchange with the mixed gas of carbon dioxide and water vapor from the gas turbine 3 for power generation by the steam turbine 5. Used.

  The propeller motor 7 is rotated by a motor driven using the electric power generated by the gas turbine 3 and the steam turbine 5 to propel the carbon dioxide sequestering ship 100.

  The exhaust gas cooler 8 cools the exhaust gas, which is a mixed gas of carbon dioxide and water vapor used for heat exchange in the steam generator 4, to an ambient level using seawater. The exhaust gas cooler 8 concentrates so that the ratio of the capacity of water vapor is about 1.5 times the ratio of the capacity of carbon dioxide.

  The carbon dioxide / water separator 9 separates the exhaust gas concentrated by the exhaust gas cooler 8 into carbon dioxide and water. The exhaust gas from the exhaust gas cooler 8 contains many water droplets. This water needs to be removed before the carbon dioxide is heat exchanged. This is because water turns into ice and causes problems in the cooler. A part of the water removed by gas-liquid separation in the carbon dioxide / water separator 9 is supplied through the water supply pipe 14 and used to lower the temperature in the gas turbine 3.

  The carbon dioxide compressor 10 first compresses the carbon dioxide from which water has been removed by the carbon dioxide / water separator 9 to 0.5 MPa. The temperature of carbon dioxide here becomes slightly higher due to a quasi-static process (polytropic change).

The carbon dioxide precooler 11 exchanges heat of the high-temperature carbon dioxide compressed by the carbon dioxide compressor 10 by using a simple plate-type heat exchanger using seawater first. To cool.
The carbon dioxide second cooler 12 further cools the carbon dioxide previously cooled by the carbon dioxide precooler 11 with a heat pump type cooler. This is because the latent heat and sensible heat of ethane utilized after the carbon dioxide precooler 11 is not sufficient to cool all the carbon dioxide to the critical point. Further, the second carbon dioxide cooler 12 can be said to compensate for the lack of cooling capacity of the carbon dioxide precooler 11.
The ethane / carbon dioxide cold heat exchanger 13 uses ethane latent heat and sensible heat to finally cool the carbon dioxide to its critical point, and liquefies the carbon dioxide in the ethane / carbon dioxide tank 1 of the carbon dioxide sequestration ship 100. Carbon is stored cold.

[Hydrocarbon fuel]
The hydrocarbon-based fuel used in the carbon dioxide sequestration ship 100 of the first embodiment refers to a compound fuel composed of carbon and hydrogen, for example, petroleum such as methane, ethane, propane, natural gas, light oil, heavy oil, and gasoline. Although it corresponds to products and the like, ethane can be particularly preferably used. The reason why ethane is preferable as a hydrocarbon fuel will be described below.
The recovered carbon dioxide is cooled to about −50 ° C. and stored at a pressure of 0.5 MPa. When a hydrocarbon fuel that approximates to carbon dioxide in a capacity at about −50 ° C. and a saturated vapor pressure is used, the fuel storage means of the hydrocarbon fuel can be used to store the recovered carbon dioxide. Among hydrocarbons, the saturated vapor pressure of ethane is closest to that of carbon dioxide. From this, by using ethane as the hydrocarbon fuel, it becomes possible to use the fuel storage means of the hydrocarbon fuel as the carbon dioxide storage means, and the fuel storage means after the hydrocarbon fuel is used. It can be used for storage of recovered carbon dioxide.

FIG. 4 is a graph showing the relationship between carbon dioxide and hydrocarbon pressure and saturation temperature. The graph is created based on the data of the JSME data book (JSME, 1983). It can be seen that ethane and carbon dioxide are very close curves among the hydrocarbons shown in the graph. Moreover, the specific heat of the hydrocarbon shown in the graph is in the same order (2.3 to 2.6 kJ / kg / K). These data show that hydrocarbon fuels with higher saturation temperatures than ethane, such as propane, cannot supply enough cooling energy to cool the recovered carbon dioxide, and methane This indicates that a hydrocarbon-based fuel having a saturation temperature lower than that of ethane requires more cooling energy to liquefy the hydrocarbon-based fuel. First, for these reasons, it can be said that ethane is most preferable among hydrocarbon fuels because it can be stored under substantially the same storage conditions as carbon dioxide.
In addition, propane and butane, which are other components in natural gas, have great demand as tank fuel in developing countries, but ethane is not as demanded as propane and butane, and is currently converted into ethylene by steam cracking. It is used by changing. As described above, since ethane is contained in a large amount in the natural gas component, the supply amount is sufficient and the demand amount is small compared to other components. This is the second reason.
In addition, when it is difficult to industrially extract ethane as pure ethane from the viewpoint of cost, a mixture containing ethane as a main component may be used. In this case, in the case of hydrocarbons having a saturation temperature higher than ethane such as butane and propane, the mixture can be handled as a liquid phase, which is preferable in terms of fuel storage and supply.

The reaction formula of oxygen and ethane combustion is as follows.
C ₂ H ₆ + 31 / 2O ₂ → 2CO ₂ + 3H ₂ O + 1561 kJ / mol (1)

Table 1 was created based on the data in the JSME data book (JSME, 1983), and shows the volume of liquid produced by combustion of ethane in oxygen. According to Table 1, it can be seen that the capacity required to recover and store the generated carbon dioxide is only 24% greater than the fuel tank.
Therefore, the ethane / carbon dioxide tank 1 can serve as both ethane storage means (fuel storage means) and carbon dioxide storage means. However, the liquid density of carbon dioxide (1178 kg / m ³ ) at 0.5 to 0.6 MPa is more than double the liquid density of ethane (497 kg / m ³ ). For example, a container ship having a cargo weight of 30,000 to 40,000 tons with a shaft output of 15,000 kW on a route between Japan and the east coast of North America has limitations on where carbon dioxide can be stored in the ocean. For this reason, it is necessary to store 120 days worth of carbon dioxide on the ship, which is equivalent to several round trips. In this case, ethane 1230 m ³ is consumed as fuel, and 1522.2 m ³ of carbon dioxide (about 1800 tons) is recovered.
In the container ship having a shaft output of 15,000 kW and a coin weight of 30,000 to 40,000 tons, ballast water of about 10,000 tons is usually used to balance the ship. In general, it is said that if one-twentieth (500 tons) of ballast water is removed, the inclination of the hull will exceed 2 degrees and adversely affect the propulsion efficiency of the ship and the work on board. For this reason, when storing the collected carbon dioxide with a weight of about 1800 tons on the ship, the balance of the hull may be lost due to the recovery of carbon dioxide if stored without considering the weight balance. is there.
For this reason, when storing the carbon dioxide recovered in the ethane / carbon dioxide tank 1, it is necessary to control the storage conditions. Among ships, especially for ships, it is important to control the storage conditions of carbon dioxide so as to balance the hull. Therefore, the configuration employed by the carbon dioxide sequestration ship 100 in order to control the fuel and carbon dioxide storage conditions will be described below.

[Control of storage conditions]
FIG. 5 is a perspective view showing an outline of a loaded state of the ethane / carbon dioxide tank 1 on the carbon dioxide sequestration ship 100. As shown in the figure, each of the carbon dioxide sequestering vessels 100 of the first embodiment includes one each at equal positions on the left and right of the center axis C indicated by a two-dot chain line parallel to the traveling direction of the carbon dioxide sequestering vessel 100. One ethane / carbon dioxide tank 1 is provided. In addition, the ethane / carbon dioxide tank 1 on the near side of the figure is shown as a state in which a part of the outer shell tank 1A is removed in order to show the internal structure.
Further, in FIG. 5, the portion indicated by the alternate long and short dash line on the carbon dioxide sequestration ship 100 is shown enlarged in the upper right. As shown in the upper right of the figure, the carbon dioxide sequestration ship 100 according to the first embodiment is configured to include seven inner tanks 1B in the outer shell tank 1A of the ethane / carbon dioxide tank (see FIG. 3 (b)). Note that the configuration of the inner tank 1B in the outer shell tank 1A is an example, and is not limited to this, as described above.
As shown in FIG. 5, the ethane / carbon dioxide tank 1 provided in the carbon dioxide sequestration ship 100 of the present embodiment equally surrounds the internal tank 1B provided at the center of the cylindrical outer shell tank 1A. In this manner, six internal tanks 1B are arranged. In the following, for convenience of explanation, based on a diagram in which the internal tanks 1B provided in the outer shell tank 1A are arranged side by side, And / or control of carbon dioxide storage conditions will be described.

FIG. 6 is a schematic diagram schematically showing a schematic configuration of the ethane / carbon dioxide tank 1. As shown in the figure, the ethane / carbon dioxide tank 1 has an outer shell tank 1A1 and an outer shell tank 1A2 on both sides of the center axis C of the carbon dioxide sequestration ship 100 (see FIG. 5) indicated by a two-dot chain line. Is provided.
Inside the outer shell tank 1A1, inner tanks 1B11 to 17 are provided in order from the farthest distance to the center axis C. In addition, internal tanks 1B21 to 27 are provided in the outer shell tank 1A2 in order from the farthest distance to the center axis C.
In the following description, the outer shell tank 1A1 and the outer shell tank 1A2 are referred to as the outer shell tank 1A, the inner tanks 1B11 to 17 are referred to as the inner tank 1B1, and the inner tanks 1B21 to 27 are not distinguished from each other. The internal tank 1B2 is referred to as the internal tank 1B when the internal tank 1B1 and the internal tank 1B2 are not distinguished from each other.

  The outer shell tank 1A includes an outer shell tank temperature sensor (storage condition control means) 15 and an outer shell tank cooler (storage condition control means) 16. The internal tank 1B includes a tank pressure sensor (storage condition control means) 17, a tank pressure regulator (storage condition control means) 18, a tank temperature sensor (storage condition control means) 19, and a tank temperature regulator (storage condition control means). ) 20. In FIG. 6, although omitted in the internal tank 1B other than the internal tank 1B11 and the internal tank 1B21, the tank pressure sensor 17, the tank pressure regulator 18, the tank temperature sensor 19 and the tank temperature regulator 20 It is provided in the tank 1B.

The outer shell tank temperature sensor 15 detects the internal temperature of each outer shell tank 1A. The outer shell tank cooler 16 controls the temperature of each outer shell tank 1 </ b> A based on the detection result of the outer shell tank temperature sensor 15.
The tank pressure sensor 17 is provided in each internal tank 1B, and detects the pressure in each internal tank 1B. The tank pressure adjuster 18 finely adjusts the pressure in each internal tank 1B based on the detection result of the tank pressure sensor 17.
The tank temperature sensor 19 detects the temperature in each internal tank 1B. The tank temperature adjuster 20 finely adjusts the temperature in each internal tank 1B based on the detection result of the tank temperature sensor 19.

  In the carbon dioxide sequestration ship 100 of the first embodiment, the internal tanks 1B11 to 15 and the internal tanks 1B21 to 25 are commonly used for storing ethane and carbon dioxide, and the internal tanks 1B16 to 17 and the internal tanks 1B26 to 27 are used. Is used only for storage of carbon dioxide. And since the same thing is used for all of the internal tanks 1B11 to 17 and the internal tanks 1B21 to 27, the storable capacity of carbon dioxide is configured to be about 40% larger than the storable capacity of ethane. For this reason, the ethane / carbon dioxide tank 1 can recover and store all of the carbon dioxide (by 24% increase in volume compared to ethane) generated by ethane oxyfuel combustion.

The internal tank 1B includes a tank valve 31 and a tank valve 32, respectively. By opening and closing the tank valve 31 and the tank valve 32, ethane in the internal tank 1B can be supplied and used as fuel, or the recovered carbon dioxide can be stored in the internal tank 1B.
Of the tank valve 31 and the tank valve 32, those connected to the internal tanks 1B11 to 15 and the internal tanks 1B21 to 25 shared for the storage of ethane and carbon dioxide are opened / closed from the internal tank 1B. The supply of ethane to the gas turbine 3 (see FIG. 2) via the carbon cold heat exchanger 13 and the storage of carbon dioxide in the internal tank 1B via the ethane / carbon dioxide cold heat exchanger 13 are controlled. And what is connected to the internal tanks 1B16 to 17 and the internal tanks 1B26 to 27 used only for storing carbon dioxide is opened and closed to the internal tank 1B via the ethane / carbon dioxide cold heat exchanger 13. It controls the storage of carbon dioxide.

Among the tank valves 31, those connected to the internal tanks 1B11 to 15 and the internal tanks 1B21 to 25 shared for storing ethane and carbon dioxide are connected to an ethane pump 21 used to supply ethane. The ethane pump 21 controls the supply of ethane from the internal tank 1B to the ethane / carbon dioxide cold heat exchanger 13 by opening and closing a pump valve 22 provided in a path leading to it.
The tank valve 32 is connected to a carbon dioxide pump 23 used for storing carbon dioxide. The carbon dioxide pump 23 opens and closes an ethane / carbon dioxide cold heat exchanger by opening and closing a pump valve 24 provided in a path leading to the carbon dioxide pump 23. The storage of carbon dioxide from 13 to the internal tank 1B is controlled.

  A flow rate sensor 25 is provided in the path between the tank valve 31 on the internal tank 1B1 side and the ethane pump 21 and in the path between the tank valve 31 on the internal tank 1B2 side and the ethane pump 21, respectively. The flow rate sensor 25 detects the flow rate of ethane from the internal tank 1B1 or the internal tank 1B2. By controlling the tank valve 31 based on the detection result by the flow sensor 25, it becomes possible to take out ethane from the internal tank 1B with an appropriate balance and amount.

A flow rate sensor 26 is provided in the path between the tank valve 32 on the inner tank 1B1 side and the carbon dioxide pump 23, and in the path between the tank valve 32 on the inner tank 1B2 side and the carbon dioxide pump 23, respectively. ing. The flow sensor 26 detects the flow rate of carbon dioxide stored in the internal tank 1B1 or the internal tank 1B2. Based on the detection result by the flow sensor 26, the opening and closing of the tank valve 32 can be controlled to store carbon dioxide in the internal tank 1B with an appropriate balance and amount.
As described above, since the flow rate sensor 25 and the flow rate sensor 26 are provided on the inner tank 1B1 side and the inner tank 1B2 side, respectively, the supply of ethane and the storage of carbon dioxide are balanced by the carbon dioxide sequestering vessel 100. It is possible to carry out in an appropriate amount while taking
The amount of ethane or carbon dioxide is adjusted by using the signals of the flow sensor 25 and the flow sensor 26 to use the ethane pump 21 and the carbon dioxide pump 23, and the balance is adjusted by opening the left and right tank valves 31 and tank valves 32. It can also be done by adjustment.

  The tank valve 31 provided in the upper part of the internal tanks 1B16 to 17 and the internal tanks 1B26 to 27 is opened when storing carbon dioxide. A ventilation valve 27 and a pressure sensor 28 are provided between the tank valve 31 and the ethane pump 21. The ventilation valve 27 is opened when the carbon dioxide stored in the internal tank 1B is stored on the seabed, thereby supplying air to the space where the carbon dioxide in the internal tank 1B is discharged. The pressure sensor 28 detects the pressure in the path from the tank valve 31 to the pump valve 22.

A ventilation valve 29 and a pressure sensor 30 are provided between the tank valve 32 and the carbon dioxide pump 23. The ventilation valve 29 is opened when supplying methane into the internal tank 1B, thereby discharging the substance in the internal tank 1B to the outside. The pressure sensor 30 detects the pressure in the path from the tank valve 32 to the pump valve 24.
The discharge pressure of the carbon dioxide pump 23 is controlled using the detection value of the pressure sensor 30, and the pressure of carbon dioxide in the internal tank 1B can be roughly adjusted. If the flow rate increases and there is a problem, the tank valve 32 is cooperated. Similarly, using the detection value of the pressure sensor 28, the opening and closing of the pump valve 22 can be switched, the discharge pressure of the ethane pump 21 can be controlled, and the pressure of ethane in the internal tank 1B can be roughly adjusted. The pressure in each internal tank 1B is finely adjusted for each internal tank 1B as described above.
The above-described valves, regulators, coolers, and the like can be controlled manually according to the detection results of each sensor, but are automatically controlled by a central processing unit (CPU, not shown). A configuration is preferable.

Below, based on FIGS. 7-8, the storage condition control to the ethane / carbon dioxide tank 1 at the time of the navigation of the carbon dioxide sequestration ship 100, the carbon dioxide seabed storage, and the ethane supply will be described.
FIG. 7 is a schematic diagram schematically showing ethane supply and carbon dioxide storage of the ethane / carbon dioxide tank 1 during navigation of the carbon dioxide sequestering ship 100. In the figure, the pump valve 22, the pump valve 24, the vent valve 27, the vent valve 29, the tank valve 31 and the tank valve 32 are shown in black in the closed state, and white in the open state. . Also, the portion containing ethane (C ₂ H ₆ ) in the internal tank 1B is shown in a dark color, the portion containing carbon dioxide (CO ₂ ) is shown in a light color, and both ethane and carbon dioxide are contained The parts that are not shown are outlined. Paths of ethane, carbon dioxide, etc. are indicated by bold lines. Note that the open / close state of the valve, the ethane and carbon dioxide in the internal tank 1B, and the way of expressing paths such as ethane and carbon dioxide are the same in FIGS.
As shown in FIG. 7, during navigation of the carbon dioxide sequestering vessel 100, the tank valve 31 and the tank valve 32 of the internal tank 1B11 and the internal tank 1B21 farthest from the center axis C are opened symmetrically with respect to the center axis C. Thus, the ethane is extracted symmetrically by the ethane pump 21 and the recovered carbon dioxide is stored symmetrically in the portion where the ethane is extracted by the carbon dioxide pump 23. Further, the recovered carbon dioxide that cannot be stored in the portion where ethane is taken out is stored symmetrically in the internal tank 1B16 and the internal tank 1B26 that are not filled with ethane. At this time, as shown in FIG. 7, the carbon dioxide sequestering vessel 100 can be balanced by symmetrically taking out ethane and storing carbon dioxide from the internal tank 1B having the same distance from the center axis C. it can. For this reason, carbon dioxide, which is nearly three times the weight of ethane consumed and discharged, can be stored in a well-balanced manner, resulting in trouble in transportation and work due to uneven weight. Can be reduced.
The order in which ethane is extracted from the internal tank 1B and carbon dioxide is stored is not particularly limited. This is preferable in order to further stabilize the carbon dioxide sequestration ship 100.

FIG. 8 is a schematic view schematically showing the extraction of carbon dioxide from the ethane / carbon dioxide tank 1 when the carbon dioxide sequestering vessel 100 stores the carbon dioxide seabed. In this figure, the state after the carbon dioxide sequestering vessel 100 oxy-combusts ethane corresponding to 4 internal tanks 1B in the outer shell tank 1A1 and 8 inner tanks 1B in the outer shell tank 1A2 for a total of 1B8 internal tanks. Is shown. As described above, the volume of carbon dioxide generated by ethane oxyfuel combustion is 24% higher than that of ethane. Therefore, in the outer shell tank 1A1 and the outer shell tank 1A2, the recovered CO 2 for the five inner tanks 1B, respectively. Carbon is stored.
When storing the carbon dioxide stored in the internal tank 1B on the seabed, the carbon dioxide sequestering ship 100 may store the carbon dioxide of the internal tank 1B which is symmetrical to the center axis C and close to the distance first on the seabed. It is preferable to balance the left and right. This is because making the internal tank 1B far from the center axis C heavier than the internal tank 1B near the center axis C balances the left and right of the center axis C and stabilizes the carbon dioxide sequestering ship 100. Therefore, it is more preferable.

  FIG. 9 is a schematic view schematically showing the supply of ethane to the internal tank 1B of the ethane / carbon dioxide tank 1 when ethane is stored in the carbon dioxide sequestration ship 100. The supply of ethane to the carbon dioxide sequestration ship 100 can also be performed using the ethane pump 21 used during navigation described with reference to FIG. As shown in the figure, even when ethane is supplied, it is preferable that the internal tank 1B located symmetrically and far from the center axis C is heavier than the internal tank 1B located near the center axis C. The ethane is supplied in order from the internal tank 1B located far from the center axis C. Thus, in the carbon dioxide sequestering vessel 100, the ethane pump 21 is commonly used for taking out ethane from the internal tank 1B and supplying ethane to the internal tank 1B.

FIG. 1 is a functional block diagram for storage condition control of the ethane / carbon dioxide tank 1 described with reference to FIGS.
As shown in the figure, the carbon dioxide sequester 100 has the following conditions for supplying and taking out ethane, and for storing and taking out carbon dioxide at the time of storage of carbon dioxide at the time of navigation, at the time of storing carbon dioxide at the bottom and at the time of supplying ethane. A setting device (storage condition control means) 40 to be controlled is provided.

The setter 40 controls the supply and extraction conditions of ethane to the internal tank 1B by controlling the tank valve 31, the pump valve 22, the ventilation valve 27, the flow sensor 25, the ethane pump 21 and the pressure sensor 28. Further, by controlling the tank valve 32, the pump valve 24, the ventilation valve 29, the flow sensor 26, the carbon dioxide pump 23, and the pressure sensor 30, the storage conditions of the recovered carbon dioxide in the internal tank 1B are controlled. At this time, the setting device 40 controls the storage conditions so that the weight and / or capacity of ethane and / or carbon dioxide stored in the ethane / carbon dioxide tank 1 is balanced.
The setting device 40 controls the temperature of the outer shell tank 1 </ b> A by controlling the outer shell tank cooler 16 based on the detection result of the outer shell tank temperature sensor 15. Further, the temperature of the internal tank 1 </ b> B is controlled by controlling the tank pressure regulator 18 based on the tank pressure sensor 17 and controlling the tank temperature regulator 20 based on the tank temperature sensor 19.

[Arrangement of ethane / carbon dioxide tank]
Although the above description is directed to a configuration in which one outer shell tank 1A is provided on each of the left and right sides of the center shaft C, the configuration of the ethane / carbon dioxide tank 1 is not limited to this. FIG. 10 is a schematic diagram showing another example that can be adopted as the configuration of the ethane / carbon dioxide tank 1, and the position of the ethane / carbon dioxide tank 1 when viewed from above the carbon dioxide sequestration ship 100. Is schematically shown.
(A) of the figure shows an example in which the outer shell tank 1A is arranged so as to straddle the center axis C of the carbon dioxide sequestering vessel 100, and the inner tanks 1B are evenly arranged on both sides of the center axis C. ing.
(B) in the figure shows an outer tank 1A3 in which an inner tank 1B for storing ethane and carbon dioxide is provided, and an inner tank 1B for storing only carbon dioxide in the inner tank 1B. The example of what is provided with the outer shell tank 1A4 currently shown is shown. In the figure, both the outer shell tank 1A3 and the outer shell tank 1A4 are arranged so as to straddle the center axis C of the carbon dioxide isolation ship 100, and the inner tanks 1B are equally arranged on both sides of the center axis C. Yes.
As in the above-described example, the configuration in which the internal tanks 1B are evenly arranged on both sides of the center shaft C makes it possible for the carbon dioxide sequestering vessel 100 to balance the storage and / or retrieval of ethane and / or carbon dioxide. It is easy to control the storage conditions of ethane and / or carbon dioxide to keep.
In addition, the distance from the center axis C to the outer shell tank 1A containing the inner tank 1B containing only ethane and the outer shell tank 1A containing the inner tank 1B containing only carbon dioxide depends on the weight ratio of ethane and carbon dioxide. May be arranged so that they are momentarily balanced. Furthermore, from the viewpoint of the purpose and the installation space of the hull, such as arranging in the longitudinal direction of the hull of the carbon dioxide sequestration ship 100 along the center axis C, and appropriately distributing in order to balance the hull in the front-rear direction. Various methods can be selected.
In addition, when hydrocarbon fuel other than ethane is used, the temperature and pressure, which are physical conditions for storage with carbon dioxide, will be separated, but the outer shell tank can be adjusted by adjusting the pressure or temperature to either. 1A and the internal tank 1B can be used in common. If the conditions are not met, these may be dedicated for hydrocarbon fuel and carbon dioxide, respectively, and stored under different physical conditions. Again, control of storage conditions becomes important.

Here, the point of “controlling storage conditions” will be specifically summarized.
First, an example of appropriately controlling the temperature, pressure, etc., which are physical conditions in storage of the fuel storage means and the carbon dioxide storage means, as described above, is to set the temperature inside the outer shell tank 1A to hydrocarbon fuel, dioxide dioxide. Controlling to temperature conditions suitable for carbon storage, and controlling the temperature and pressure inside the internal tank 1B to conditions suitable for storage of hydrocarbon fuel and carbon dioxide can be mentioned. In addition, it includes keeping both the hydrocarbon fuel and carbon dioxide in a liquid phase.
In addition, as described above, an example of controlling so as to reduce the effects of weight balance and capacity balance disruption due to differences in the density and capacity of hydrocarbon-based fuel and recovered carbon dioxide is as described above. Supply and storage symmetrically with respect to the axis C, supply and storage from the internal tank 1B far from the center axis C, and the like. In addition to this, it includes supply and storage control so that momentary balance is achieved. In this case, the supply and storage of the internal tank 1B are appropriately controlled by calculating from the arrangement, supply and storage accumulation amount for the internal tank 1B, and the supply and storage are feedback-controlled using an inclination sensor or the like for detecting the balance. Etc. can also be performed.
Examples of controlling storage according to the form, shape, and arrangement conditions of the fuel storage means and the carbon dioxide storage means are various arrangements of the internal tank 1B as seen in FIGS. 3 (a), (b), and (c). Depending on the situation, control is performed to supply hydrocarbon fuel and store carbon dioxide so that the weight is balanced, and there is a difference between the supply of hydrocarbon fuel and the amount of carbon dioxide recovered. For example, the carbon dioxide is appropriately distributed to the 1B16-17 and the internal tanks 1B26-27 and stored in a capacity-balanced manner. In addition, when there are a plurality of diameters and volumes of the internal tank 1B, it is possible to control the weight balance and the capacity balance in consideration of this point. Further, when the ethane / carbon dioxide tank 1 does not have a diaphragm for separating ethane and carbon dioxide, control is performed so that high-density carbon dioxide is introduced from below, and a diaphragm is provided. Includes the introduction of high-density carbon dioxide from above and the use of ethane to push out the carbon dioxide by its own weight.

[Transportation by LNG carrier]
FIG. 11 is a perspective view schematically showing a carbon dioxide sequestration ship 200 that transports LNG (liquefied natural gas), which is a hydrocarbon-based fuel, as a transport target in an LNG (liquefied natural gas) transport ship. As shown in the figure, the carbon dioxide sequestration ship 200 includes a plurality of LNG tanks 201, and stores LNG to be transported therein.
When LNG is transported by the LNG tank 201, the vaporized LNG accumulates in the upper space 201A inside the LNG tank 201. Therefore, by using this vaporized LNG as a hydrocarbon fuel, it is not necessary to provide a tank for storing the hydrocarbon fuel in the carbon dioxide sequestering ship 200. In this case, since the recovered carbon dioxide cannot be stored in the LNG tank 201, the carbon dioxide sequestering ship 200 balances the left and right tanks 202 for storing the recovered carbon dioxide separately from the LNG tank 201. Arranged in consideration.
The number of LNG transport ships is expected to increase dramatically in the future, but by using LNG as the transport target fuel as a hydrocarbon-based fuel, the transport target fuel storage means is also used as the fuel storage means. be able to. Thereby, it is not necessary to separately provide fuel storage means, and the carbon dioxide sequestration ship 200 can be realized with a simple configuration.

(Embodiment 2)
Embodiment 2 in which the present invention is implemented as a carbon dioxide recovery processing method for transporting carbon dioxide recovered and stored in a carbon dioxide storage means to a predetermined place using the carbon dioxide sequestration ship 100 described in Embodiment 1. This will be described below with reference to FIG.
FIG. 12 is a schematic diagram for explaining the outline of the carbon dioxide recovery processing method according to the second embodiment of the present invention. As shown in the figure, the carbon dioxide recovery processing method of the second embodiment uses a carbon dioxide sequestration ship 100 as a transportation means, and transports carbon dioxide transported to a predetermined location to the sea or below the sea floor. It is to be stored. More specifically, the recovered carbon dioxide is transferred to the aquifer under the ocean floor about 500 m below the sea surface, which is a typical carbon dioxide reservoir, and stored by the pipe 110. The pipe 110 sends liquid carbon dioxide to the aquifer, and a hydrate of carbon dioxide is formed around the carbon dioxide outlet.

  In addition, when storing carbon dioxide underwater or under the seabed, weight balance control can be performed in cooperation with the ballast hydrostatic drainage system of the carbon dioxide sequestering ship 100 when carbon dioxide is transferred underwater or under the seabed. preferable. Thus, when transferring carbon dioxide from the ethane / carbon dioxide tank 1 (see FIG. 5) to the aquifer, the amount of carbon dioxide in the ethane / carbon dioxide tank 1 is reduced, so that the carbon dioxide sequester 100 It is possible to prevent the balance from being lost. More specifically, in consideration of balance, carbon dioxide is transferred from the ethane / carbon dioxide tank 1, and an amount of ballast water corresponding to the transferred carbon dioxide is taken into the ballast water-filled drainage system, It is possible to prevent the carbon dioxide sequestration ship 100 from being out of balance due to a change in the amount of carbon dioxide in the ethane / carbon dioxide tank 1.

  Reducing GHG emissions is an important issue to be solved internationally. And it is said that sustainable growth will be hopeless if the ship does not aim for a zero emission rate of around 80% in 2035 by 2035. For this reason, the carbon dioxide recovery processing method of the second embodiment by GHG subseafloor sequestration (CCS), which is also recognized by IMO, is effective as a method for reducing the amount of GHG emission. In addition, since a carbon dioxide submarine isolated offshore station for the purpose of carbon dioxide sequestration from ships can be used, the total cost may be lower than the purchase of carbon dioxide emission rights.

  INDUSTRIAL APPLICABILITY The present invention can be used for the separation and recovery of carbon dioxide emitted from transportation means such as ships, cars, trains, etc. in order to reduce the amount of greenhouse gas emissions.

1 Ethane / carbon dioxide tank (fuel storage means, carbon dioxide storage means)
1A, 1A1, 1A2, 1A3, 1A4 outer shell tank (fuel storage means, carbon dioxide storage means)
1B, 1B11-17, 1B21-27 Internal tank (fuel storage means, carbon dioxide storage means)
2 Oxygen generator (oxygen separation means)
3 Gas turbine (energy conversion means)
3A body (energy conversion means)
3B generator (energy conversion means)
5 Steam turbine (energy conversion means)
5A body (energy conversion means)
5B generator (energy conversion means)
7 Propeller motor (drive means)
8 Exhaust gas cooler (carbon dioxide extraction processing means)
9 Carbon dioxide / water separator (carbon dioxide extraction means, water addition means)
10 Carbon dioxide compressor (carbon dioxide processing means)
11 Carbon dioxide precooler (carbon dioxide treatment means)
12 Carbon dioxide second cooler (carbon dioxide treatment means)
13 Ethane / carbon dioxide cold heat exchanger (carbon dioxide treatment means, storage condition control means, cold heat exchange means)
14 Water supply pipe (water addition means)
15 Outer shell temperature sensor (storage condition control means)
16 Shell tank cooler (storage condition control means)
17 Tank pressure sensor (storage condition control means)
18 Tank pressure regulator (storage condition control means)
19 Tank temperature sensor (storage condition control means)
20 Tank temperature controller (storage condition control means)
40 Setter (Storage condition control means)
100, 200 carbon dioxide sequestration ship

Claims (15)

  Drive means, fuel storage means for storing hydrocarbon fuel, energy conversion means for extracting energy using hydrocarbon fuel and oxygen supplied from the fuel storage means, and exhausted from the energy conversion means Carbon dioxide processing means for processing carbon dioxide in the exhaust gas so that it can be stored, carbon dioxide storage means for recovering and storing carbon dioxide treated by the carbon dioxide processing means, the fuel storage means, and the carbon dioxide A transportation means with a carbon dioxide recovery function, comprising storage condition control means for controlling storage conditions of the storage means.     The transportation means with carbon dioxide recovery function according to claim 1, wherein the storage condition control means controls the temperature of the fuel storage means and / or the carbon dioxide storage means.   3. The carbon dioxide recovery function according to claim 1, wherein the hydrocarbon fuel is ethane or a mixture of ethane as a main component and hydrocarbon having a saturation temperature equal to or higher than ethane. 4. Means of transport.   The transportation means with a carbon dioxide recovery function according to claim 3, wherein the fuel storage means also serves as the carbon dioxide storage means.   5. The carbon dioxide according to claim 1, wherein the fuel storage means and the carbon dioxide storage means are arranged in a weight balance with respect to the transportation means. Transportation means with a recovery function.   The storage condition control means controls storage conditions of the fuel storage means and the carbon dioxide storage means so that a balance between weight and / or capacity can be achieved. The transport means with a carbon dioxide recovery function according to any one of claims 5 to 5.   2. The carbon dioxide treatment means includes a cold heat exchange means provided in a path for supplying the hydrocarbon fuel stored in the fuel storage means in a liquefied state to the energy conversion means. The transport means with a carbon dioxide recovery function according to one of claims 6 to 7.   8. The transportation means with a carbon dioxide recovery function according to claim 1, further comprising an oxygen separation means for taking out oxygen from the atmosphere supplying oxygen.   The transportation with a carbon dioxide recovery function according to claim 1, further comprising a water addition unit that adds water when energy conversion is performed by the energy conversion unit. means.   10. The transport means with a carbon dioxide recovery function according to claim 1, further comprising a carbon dioxide extraction means for extracting carbon dioxide from the exhaust gas.   The transportation means with a carbon dioxide recovery function according to claim 1, wherein the transportation means is a ship.   The transportation means with a carbon dioxide recovery function according to claim 1, wherein the hydrocarbon fuel is also a transportation target fuel of the transportation means.   The carbon dioxide recovered and stored in the carbon dioxide storage means is transported to a predetermined place using the transport means with carbon dioxide recovery function according to one of claims 1 to 12. A characteristic carbon dioxide recovery method.   14. The method for recovering carbon dioxide according to claim 13, wherein the transport means is a ship, and transports and stores the carbon dioxide transported to the predetermined location in the sea or under the seabed.   In storing the carbon dioxide in the sea or under the seabed, the balance control in weight is performed in cooperation with the ship's ballast hydrostatic drainage system when transferring the carbon dioxide into the sea or under the seabed. The method for recovering carbon dioxide according to claim 14, wherein the carbon dioxide is recovered.