JP4044899B2 - Gas hydrate transport ship - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas hydrate transport ship for transporting a so-called gas hydrate composed of a gas mainly composed of methane such as natural gas and water.
[0002]
[Prior art]
Conventionally, natural gas is transported as liquefied natural gas (hereinafter referred to as LNG) or high-pressure gas filled in a cylinder.
[0003]
However, since LNG needs to be transported with the cargo temperature kept at −162 ° C., a special transport ship having a specially manufactured expensive storage tank, that is, an LNG ship is required. Moreover, since LNG turns a natural gas into a liquid of -162 degreeC, it is necessary to input much energy for the manufacture. In addition, LNG is very dangerous because it rapidly vaporizes when temperature control fails. Moreover, since LNG is extremely low in temperature as described above, it has a high vaporization rate and is not suitable for long-term storage.
[0004]
On the other hand, natural gas and other methane-based gases have attracted attention as clean energy sources and raw materials for various products. For transportation and storage, natural gas and other methane-based gases are used artificially. Alternatively, research on industrial gas hydrate (hereinafter referred to as NGH) is being conducted.
[0005]
NGH is in the basket to make the water molecules have a crystal structure in which molecules of the gas is within one by one, for example, in the methane hydrate, 164m ³ in methane hydrate 1 m ³ at atmospheric pressure It is said that it can contain methane. Of these, the volume of water is 0.8 m ³ .
[0006]
Thus, since methane hydrate has a high gas storage property, it attracts attention as a new transport and storage body of natural gas that replaces LNG. The density of methane gas in methane hydrate is about 3.5 times lower than that of LNG. However, when it is produced artificially or industrially, the liquefaction temperature, ie, −162 ° C., is the same as LNG. It is said that energy efficiency is greatly improved because there is no need to cool to:
[0007]
In the case of artificially producing methane hydrate, for example, water or antifreeze is sprayed from the spraying means in a pressure vessel maintained at a temperature of 1 to 10 ° C. and a pressure of 30 to 100 atm, and methane gas is supplied from a supply pipe. Supply. Alternatively, methane gas is injected into water or antifreeze. Then, water or antifreeze and methane gas are synthesized to produce powdered methane hydrate.
[0008]
Powdery methane hydrate, because rate filling (volume / volume reservoir of methane hydrate) is small, and when the transportation and storage, thought to be formed into pellets by granulating machine such as a pair Retaiza It has been. In order to transport such a gas hydrate, a new transport ship replacing the LNG ship is required.
[0009]
[Problems to be solved by the invention]
The present invention has been made based on such a demand, and an object of the present invention is to provide a gas hydrate transport ship suitable for transporting gas hydrate.
[0010]
[Means for Solving the Problems]
The gas hydrate transport ship of the present invention according to claim 1 is provided with one or more holds in the fore and aft directions of the hull, respectively, and a load for distributing powder or granular gas hydrate to each hold. And an unloading device for discharging the gas hydrate stored in the hold to the outside of the ship, and further, the loading device, a first conveyor for transferring the gas hydrate in the bow-stern direction, It comprises a plate-like distribution device that is arranged obliquely on the first conveyor and can be moved intermittently in the fore-and-aft direction and a supply device, and the supply device is located at the end of the first conveyor A main conveyor provided in a gas hydrate carry-in / out area, and a slide conveyor that slides in the width direction of the hull with respect to the main conveyor and distributes powder or granular gas hydrate to a plurality of first conveyors Form, further, in the gas hydrate transport ship for sealing over the upper and gas hydrate unloading the arrival of the cargo hold in the outer shell, randomly gas hydrate pellets formulations having a large and small pores below the dispensing device A board is installed .
[0011]
The gas hydrate transport ship according to claim 2 of the present invention is the gas hydrate transport ship according to claim 1, wherein the discharge port is provided at the lower end of the hold, and the diameter D of each discharge port is apparent from the pellet-like gas hydrate. It is characterized by being set to at least about 4 times the diameter .
[0012]
The gas hydrate transport ship of the present invention according to claim 3 travels in claim 1 while spraying water on the outer shell covering the upper part of the hold and the gas hydrate loading / unloading area at the time of navigation. It is characterized by that.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, a case where gas hydrate obtained by forming powdery gas hydrate into pellets by a granulator such as a pelletizer is transported is taken as an example.
[0014]
As shown in FIG. 1 , the gas hydrate transport ship 1 has a large number of holds 3 in a hull 2. These holds 3 are arranged in a lattice shape to prevent the collapse of the gas hydrate stored in the holds 3.
[0015]
As shown in FIG. 3 , the hold 3 has an input port 4 at its upper end and a discharge port 5 at its lower end. The diameter D of the discharge port 5 is desirably set to at least about 4 times the apparent diameter of the pellet-like gas hydrate a. Moreover, it is desirable to set the inclination angle θ of the bottom of the hold to 20 to 50 °.
[0016]
A baffle plate / hatch 6 that can be moved up and down is provided directly below the inlet 4, and the pellet-shaped gas hydrate a is loaded evenly and is broken when the pellet-shaped gas hydrate a falls on the bottom of the hold 3. Consideration is not given.
[0017]
In this example, the hold 3 is arranged in a 3-row column, but the exposed portion is covered with a heat insulating material 7 such as urethane foam, plywood, balsa, pearlite, etc., and the inside of the hold 3 is at a predetermined temperature, for example, Celsius. The temperature is maintained at -5 ° C to -30 ° C.
[0018]
Even if a jacket (not shown) provided outside the hold 3 is filled with a medium having low thermal conductivity such as water or oil, or antifreeze liquid, and the hold 3 is kept at a predetermined set temperature. There is no problem. Furthermore, there is no problem even if the coolant is circulated in a cooling jacket (not shown) provided outside the hold 3 and the inside of the hold 3 is forcibly cooled to a predetermined set temperature. In the figure, 8 indicates a gate and 9 indicates a ballast tank.
[0019]
As shown in FIG. 4 , the rear of the hold 3 is a carry-in / out area 10. Returning to FIG. 1, the transport ship 1 includes a conveyor type loading device 11. The loading device 11 includes a first conveyor 12, a distribution device 13, and a supply device 14.
[0020]
As described above, the hold 30 is in a three-row column, and the first conveyor 12 is provided directly above each hold group 30. In addition, the distribution device 13 includes a distribution plate 15 that can move intermittently in the bow-stern direction along the first conveyor 12. The distribution plate 15 is provided obliquely with respect to the first conveyor 12, and supplies or distributes the pellet-shaped gas hydrate a carried by the first conveyor 12 to a predetermined hold 3.
[0021]
A supply device 14 is provided in the carry-in / out area 10 where the rear end portion of the first conveyor 12 is located. The supply apparatus 14 is comprised from the main conveyor 16 and the slide conveyor 17 (refer FIG. 2 ) which can be slid. By moving the slide conveyor 17 forward and backward, that is, in the transverse direction of the hull 2, the pellet-shaped gas hydrate a is distributed to the first conveyor 12.
[0022]
When the main conveyor 16 is operated after the tip of the slide conveyor 17 is positioned on the predetermined first conveyor 12, the pellet-shaped gas hydrate a passes from the main conveyor 16 through the slide conveyor 17 to the first conveyor. 12 is supplied. The pellet-shaped gas hydrate a supplied to the first conveyor 12 is transferred by the first conveyor 12 in the bow direction. And the hand which goes to the distribution board 15 set right above the predetermined hold 3 is blocked | interrupted, and it falls into the predetermined hold 3 and is stored.
[0023]
As shown in FIG. 1, an outer shell 19 is provided on the deck 18 so as to cover the upper part of the hold group 30 and the loading / unloading area 10 , and the upper part thereof is sealed. As shown in FIG. 2, an opening 20 is provided on the side surface of the outer shell 19 so as to be located in the carry-in / out area. A detachable sealing means 21 for sealing the supply device 14 is attached to the opening 20. The sealing means 21 has a bellows-like tip portion, and can freely expand and contract. The opening 20 includes a hatch (not shown).
[0024]
As shown in FIG. 4 , the gas hydrate transport ship 1 includes a conveyor-type unloading device 23. The unloading device 23 conveys the second conveyor 24 provided below the hold group 30 and the pellet-shaped gas hydrate a transferred by the second conveyor 24 to the cargo handling device 25 (see FIG. 5 ) outside the ship . And a vertical lift device 26.
[0025]
As shown in FIG. 5 , the vertical lift device 26 includes a tank 27 with a chute and a screw conveyor 28 erected on the tank 27. Between the second conveyor 24 and the tank 27, A funnel-shaped chute 29 is provided.
[0026]
A conveyor 31 is used for the outboard cargo handling apparatus 25. The conveyor 31 is inserted from the opening 20 provided on the side surface of the outer shell 19 already described. The conveyor 31 is not limited to a screw conveyor, and a belt-like conveyor can be used. Reference numeral 21 denotes a bellows-like sealing means.
[0027]
Thus, the pellet-like gas hydrate a discharged into the tank 27 by the second conveyor 24 is transferred upward by the vertical screw conveyor 28 and is transferred from the duct 32 of the screw conveyor 28 to the conveyor 31 of the cargo handling device 25. Supplied. Then, the cargo is unloaded by the conveyor 31.
[0028]
The vertical screw conveyor 28 and the cargo handling conveyor 31 for lifting the pellet-shaped gas hydrate a desirably use carbon dioxide gas, nitrogen gas, methane gas, or the like as a pressure feed gas. Further, when sailing, it is desirable to sail while spraying water on the deck 18 and the outer shell 19.
[0029]
In the above description, the belt conveyor type loading device has been described. However, a chute type loading device can be applied as described below. In addition, the same code | symbol is attached | subjected to the apparatus which has the same function, and detailed description is abbreviate | omitted.
[0030]
As shown in FIG. 6 , a cart 34 is on a chute-type load device 11 a and a rail 33 in the bow-stern direction installed on the deck 18, and a distribution device 35 is provided on the cart 34. As shown in FIG. 8 , the distribution device 35 includes a hopper 36 and a plurality of (three in the figure) chutes 37a, 27b, and 37c attached to the hopper 36.
[0031]
As shown in FIG. 6 , these chutes 37a, 27b, and 37c are provided so as to simultaneously correspond to the three holds 3 arranged in a horizontal row. Further, as shown in FIG. 7 , the distributor 35 has a multi-noded seal plate 38 such as a shutter. The end portion of the seal plate 38 is provided in an endless shape, and the end portions are attached to the front and rear ends of the hopper 36 in an airtight manner. A gap between the sealing plate 38 and the outer shell 19 installed on the deck 18 is also sealed with a sealing material (not shown). As shown in FIG. 8 , the hopper 36 is partitioned for each chute 37a, 27b, 37c by partition plates 39a, 39b.
[0032]
Thus, when the pellet-like gas hydrate a is supplied from the duct 40 connected on the hopper 36, the pellet-like gas is put into the three holds 3 arranged in the lateral direction through the chutes 37a, 27b, 37c. Hydrate a is supplied simultaneously.
[0033]
A pipe conveyor can be used as the cargo handling conveyor. Various types of pipe conveyors are known . For example, when a plurality of semicircular fins 41 are attached to a conveyor 42 at a predetermined pitch as shown in FIGS. The gas hydrate a can be transferred more reliably.
[0034]
Further, as the lift device, for example, a lift device 26 a as shown in FIG. 11 can be used instead of the vertical screw conveyor 28. This lift device 26a is a device in which a large number of buckets 43 are mounted on an endless member 45 that spans a pair of upper and lower wheels 46 , 44, and on the side that lifts the pellet-like gas hydrate a (the left side in the figure) The bucket interval is increased, and the bucket interval is decreased on the return side (right side in the figure).
[0035]
In addition, a cylinder system (not shown) can be adopted as the lift device. This device has a structure in which a piston-like object in a vertical cylinder is raised and lowered by a hydraulic cylinder.
[0036]
As the payout device, a floating payout device 47 shown in FIGS . 12 and 13 can be used. The dispensing device 47 ejects the gas b from a large number of small holes 49 provided in the passage 48 and transfers it to the box 50 containing the pellet-shaped gas hydrate a.
[0037]
Further, as shown in FIG. 14 , a knitted fabric 52 is installed in the pipe 51, and for example, a gas such as methane gas is blown out from the knitted fabric of the woven fabric 52 to increase the fluidity of the pellet-like gas hydrate a. It can also be.
[0038]
When the above-mentioned cargo hold 3 vibrates an ultrasonic transducer (not shown) attached to the bottom thereof or rotates a stirring blade (not shown) provided in the hold, a pellet-like gas hydrate a It becomes easy to take out.
[0039]
Also, a rubber coating (not shown) is attached to the bottom of the hold 3 and when the pellet-like gas hydrate a is dispensed, gas is injected between the hold 3 and the coating to transform the coating into a hopper shape. It is possible to make it.
[0040]
Further, as shown in FIG. 15, be rotated as shown by an arrow in the ladder with movable chute 53 disposed below the conveyor 12, it is possible to make reduce the impact of the fall of the pellets of gas hydrate a. Other examples of the impact mitigation method include a method using a slide chute , a method using a curved tube, and a method using a Jinkasa distributor.
[0041]
In order to improve the filling rate of the pellet-like gas hydrate a, for example, as shown in FIG. 16 , a large-diameter hole 56 and a small-diameter hole 57 are randomly provided below the distribution means (duct) 54. The mixing plate 55 provided in the above can be installed, and the gap between the large-diameter pellet-like gas hydrates a ′ can be filled with the small-diameter pellet-like gas hydrate a ″.
[0042]
As another cargo handling method, for example, an air current conveying method can be cited. For example, the mixing ratio is set to 10 to 15 and, for example, the pellet-shaped gas hydrate a is entirely air-flowed using methane gas, or only vertically transported using methane gas. It is transferred using a pipe conveyor. Methane gas used for transportation is supplied from the land and circulated.
[0043]
Moreover, the system which cools (-20 degreeC) simultaneously with conveying a pellet-shaped gas hydrate with pressurized gas (-20 degreeC) is also employable.
[0044]
【The invention's effect】
As described above, the invention according to claim 1 is provided with one or more holds in the fore and aft directions of the hull, respectively, and a cargo device that distributes powder or granular gas hydrate to each hold, and the hold An unloading device for discharging the gas hydrate stored in the ship to the outside of the ship , and further, the loading device has a first conveyor for transferring the gas hydrate in the bow-stern direction, and on the first conveyor. The plate-type distribution device which is arranged diagonally and can be moved intermittently in the fore-and-aft direction and a supply device, and the supply device is carried in and out of the gas hydrate located at the end of the first conveyor constitutes a main conveyor provided in frequency, by a slide conveyor for distributing a plurality of first conveyor powdered or granular gas hydrate slides in the widthwise direction of the hull with respect to the main conveyor, further, the In the gas hydrate transport ship that covers and seals the upper part of the storehouse and the gas hydrate carry-in / out area with the outer shell, since the gas hydrate pellet blending plate with small and large holes provided at random below the distributor is installed, The gap between the large-diameter pellet-like gas hydrates can be filled with the small-diameter pellet-like gas hydrate, and the filling rate of the pellet-like gas hydrate can be improved.
[0048]
[Industrial applicability]
In the above description, the case where the pellet-like gas hydrate is transported has been described. However, the present invention can be applied to the case where the powder-like gas hydrate is transported.
[0049]
[Brief description of the drawings]
FIG . 1 is a perspective view of a gas hydrate transport ship according to the present invention.
FIG . 2 is an enlarged perspective view of a main part of a gas hydrate transport ship according to the present invention.
FIG . 3 is a cross-sectional view of a gas hydrate transport ship according to the present invention.
FIG . 4 is a longitudinal sectional view of a carry-in / out area.
FIG . 5 is a longitudinal sectional view of a lift device.
FIG . 6 is a front view of the distribution device.
FIG . 7 is a perspective view of a chute.
FIG . 8 is a perspective view of a distribution device.
FIG . 9 is a developed state diagram of the conveyor.
FIG . 10 is a diagram illustrating a gripping state of the conveyor.
FIG . 11 is a side view of an alternative to the lift device.
FIG . 12 is a longitudinal sectional view of the dispensing device.
FIG . 13 is a perspective view of the dispensing device.
FIG . 14 is a perspective view of an alternative to the transport device.
FIG . 15 is an explanatory diagram of a crush prevention means.
FIG . 16 is a perspective view of a blending apparatus.
[0050]
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Gas hydrate transport ship 3 Ship hold 7 Heat-insulating material 10 Carry-in / out area 11, 11a Loading device 19 Outer shell 23 Unloading device 30 Ship hold group

Claims (3)

The stern direction and transverse direction of the hull provided with a respective one or more hold, the cargo equipment for distributing the powdered or granular gas hydrate in each hold, the gas hydrate is stored in said hold ship An unloading device for delivering to the outside, and further, the loading device is disposed on the first conveyor at an angle to the first conveyor for transferring the gas hydrate in the bow-stern direction, and in the bow-stern direction. A plate-like distribution device that can move intermittently and a supply device. The supply device is provided in a main conveyor provided in a gas hydrate carry-in / out area located at an end of the first conveyor, and the main conveyor. On the other hand, it is constituted by a slide conveyor that slides in the width direction of the hull and distributes powder or granular gas hydrate to a plurality of first conveyors, and further above the cargo hold and gas hydrate carry-in / out The in gas hydrate transport vessels to seal covering an outer shell, said dispensing device for a gas hydrate transport ship, characterized in that it has established a gas hydrate pellets formulated plate provided randomly magnitude of holes downward. 2. The gas hydrate according to claim 1 , wherein a discharge port is provided at a lower end of the hold, and a diameter D of each discharge port is set to at least about four times the apparent diameter of the pellet-like gas hydrate. Transport ship. 2. The gas hydrate transport ship according to claim 1, wherein the ship moves while spraying water on the outer shell covering the upper part of the cargo hold and the gas hydrate carry-in / out area during navigation .

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