KR101420930B1 - Drain tower apparatus for NGH regasification - Google Patents

Abstract

The present invention relates to a drain tower device for regasification of natural gas hydrates, and more particularly, to a device for continuously discharging hot water and dissociation water sprayed to dissociate NGH.
A drain tower apparatus for regasifying natural gas hydrates according to the present invention is a drain apparatus for a cargo hold having a natural gas hydrate loaded therein, the drain tower apparatus comprising: a base portion having a cylindrical shape and installed at a bottom of the cargo hold; And a plurality of U-shaped heating tubes each having an inlet and an outlet, the U-shaped heating tubes being spaced from the adjacent U-shaped heating tubes by a predetermined distance And a heating tube portion coupled to the upper portion of the base portion in a direction perpendicular to a circumference having a predetermined diameter.
According to the drain tower apparatus for regasifying natural gas hydrates according to the present invention, it is possible to prevent the injection nozzle from being frozen and not operated in hot water injection for direct heat supply in order to dissociate NGH.

Description

[0001] Drain tower apparatus for NGH regasification for regasification of natural gas hydrates [0002]

The present invention relates to a drain tower device for regasification of natural gas hydrates, and more particularly, to a device for continuously discharging hot water and dissociation water sprayed to dissociate NGH.

Natural gas hydrate (NGH) is a substance in which natural gas molecules are solidified between water molecules in the course of solidification of water at high pressure and low temperature in a gaseous state.

The formed hydrate (natural gas hydrate) is stored under normal pressure at low temperature (-20 ℃) and is being studied as natural gas transportation means by taking advantage of this property.

The disadvantage of luggage as a means of transporting natural gas is that it needs to be shut off and shut off during loading or unloading, at which time the loading or unloading path should be kept at -20 ° C.

In this case, since the characteristic of the baggage is a solid state, it can not use a transfer method such as a pump, and therefore, there is a problem about a method of unloading (loading or unloading) a transportation line requiring a large amount of loading or unloading in a short time.

In order to solve such a problem, Japanese Patent Application Laid-Open No. 2005-255076 (a method of unloading a gas hydrate transportation line and the gas hydrate transportation line) and a technique of discharging a gas hydrate transportation line Laid-Open Patent Publication No. 2011-0003616 (natural gas hydrate transportation line).

Further, in order to separate the natural gas contained in the natural gas hydrate, a heat source is supplied to the hydrate, and the natural gas hydrate is dissociated by heating to a temperature above the generation temperature.

As shown in Fig. 1, the gas hydrate transportation line and the gas hydrate transportation line are carried by a main water pipe 7 in the dock 5, in the gas hydrate transportation line carrying the gas hydrate (p) (A) is injected into the hold 5 by the main water pipe 5 when the gas hydrate p is unloaded (unloaded), and the hot water a and the gas hydrate p are brought into direct contact with each other Thereby pyrolyzing the gas hydrate (p).

As shown in FIG. 2, the natural gas hydrate transportation line 100 includes a storage tank 110 installed to store natural gas hydrate in the hull, (120) for collecting water dissociated from the natural gas hydrate in the water collecting part (110), a first heating part (130) for heating the water collected in the water collecting part (120) (130) is injected into the storage tank (110).

To dissociate the natural gas hydrate, the natural gas hydrate dissociation method has been used so that the hot water is directly contacted to supply the heat source to the natural gas hydrate, or the heat quantity is supplied using the heating coil.

These methods refer to a method of supplying a heat source and a system therefor to dissociate the natural gas hydrate, but do not consider the state in which the natural gas hydrate is dripped into the transport line or the storage tank.

Since the storage temperature of natural gas hydrate in the cargo holds is around -20 ℃, the nozzle should be managed so that the nozzle will freeze when the water is sprayed directly.

In addition, when the hot water, which is a heat source, is sprayed through the nozzle and dissociated, a movement path for disposing the generated gas and water should be secured.

When the actual height of the natural gas hydrate storage tanks is more than 10 meters, the first loaded natural gas hydrate pellets (NGH pellets) are subjected to a large load at the bottom of the cargo hold, resulting in breakage of the pellet shape and becoming a lump of pellets Thereby obstructing the movement path of gas and water.

Particularly, in the hot water spraying method, when the hot water is sprayed from the upper part due to such phenomenon, the hot water sprayed is not drained. When the hot water is sprayed from the lower part, as shown in FIG. 3, The internal pressure is increased to become a dangerous state.

Generally, to dissociate natural gas hydrates, 500 kJ / kg of heat is required. In the case of a natural gas cargo carrier, when 10,000 tons of natural gas hydrate is stored in one cargo hold, the total heat required for dissociation is 5,000 GJ, Is assumed to be 7 days, it needs 29.86 GJ / h per hour.

When a heating coil is used to supply such a heat quantity, a coil requires a large heat transfer area, which is a direct factor for raising the price and also a lot of power consumption for generating heat energy.

In the case of a nozzle injection type in which a large number of heat energy sources required for dissociation can be directly dissociated from the waste heat of a power plant, a large amount of flow is required per unit time in order to transfer heat energy within a limited time.

Table 1 and Table 2 show the calorific value and the water flow rate to be supplied in the cargo hold to dissociate the natural gas hydrate.

NGH (Ton: Ton) Size of hold (m ³ ) Harry calories (kJ) Unloading date Calories per hour (kJ / h) 10,000 14,815 5,000,000,000 7 29,761,904.76

NGH (Ton: Ton) Calories per hour
(kJ / h) Injection temperature
(° C) Drainage temperature
(° C) Δt
(° C) Specific heat of water
(kJ / kg DEG C) flux
(Ton / h) 10,000 29,761,904.76 80 10 70 4.18 102

In order to dissolve 10,000 tons of natural gas hydrate for 7 days, 102 tons of hot water should be supplied per hour. It is necessary to treat the water generated by dissociation of water and natural gas hydrate (NGH) to supply heat source. Can be maintained.

Therefore, the flow rate of hot water to be supplied in the cargo hold is 102 Ton / h, but the flow rate to be drained is 102 Ton / h + 10,000 Ton / (7 days * 24h) = 160 Ton / h.

However, since the loaded natural gas hydrate is stored at -20 ° C, it is easy for the drain lines and valves to freeze and become inoperable, and the NGH pellet loaded at the bottom of the cargo holds the time As a lump, the water sprayed from the top blocks all the passages that are discharged to the bottom of the hold, making it difficult to discharge the supplied water.

In addition, the hot water injected for the purpose of dissociation of the cargo hold dissociates the NGH pellet directly by the amount of water around the injection nozzle. However, as the dissociated water and injected water fall down below the NGH hold, Frozen again between the pellets.

If the water generated by the injected water and the dissociation freezes between the pellets, it is no longer possible to carry out hot water injection into the cargo hold due to the lack of drainage in the NGH hold, Requires facilities.

DISCLOSURE OF THE INVENTION It is an object of the present invention to solve the above-described problems, and it is an object of the present invention to provide a method for recovering NGH, which comprises supplying hot water (or hot water) to dissociate directly in a cargo hold storing NGH, And to provide a drain tower device for regasification of natural gas hydrate which can be used for natural gas hydrate regeneration.

To solve the above problems, a drain tower apparatus for regasifying natural gas hydrates according to the present invention is a drain tower apparatus for a drainage apparatus for a cargo hold having a natural gas hydrate loaded therein. The drain tower apparatus includes a cylindrical body, part; And a plurality of U-shaped heating tubes each having a U-shaped heating tube and a U-shaped heating tube each having an inlet and an outlet, And a heating tube portion which is disposed perpendicularly to the base portion by forming a circle on a base portion having a diameter so as to have a water pump at an upper portion of the base portion.

The base portion is formed as an upper portion and an empty space for supporting and fixing a flow path through which a U-shaped heating tube is drawn or drawn to the base portion, and a flow path through which the U- .

The heating tube unit may include a plurality of injection ports connected to the water pump and an antifreeze storage tank connected to a plurality of outflow ports integrated with the plurality of injection ports to efficiently heat the heating tube.

The heating tube portion circulates the medium in a U-shaped heating tube, and the distance between the inlet and outlet flow paths of the U-shaped heating tube is the same as the distance between the U-shaped heating tubes.

In addition, the medium is ethylene glycol which is heated so that dissociation of natural gas hydrate and water supplied from the outside do not freeze.

In addition, the base portion has a water pump at an upper portion thereof, and drains the mixed solution of hot water and dissociated water supplied through the dissociation reaction to the outside of the cargo hold through a pipe connected to the water pump.

In addition, the base part binds the heating tube part with a belt-shaped supporting means such that the U-shaped heating tubes are vertically installed at regular intervals.

In addition, the cargo hold has a plurality of drain tower units therein to drain mixed solution of hot water and dissociated water supplied from the outside to the outside of the cargo hold.

According to the drain tower apparatus for regeneration of natural gas hydrates according to the present invention, it is possible to prevent the injection nozzle from being frozen and not operated in hot water injection for direct heat supply in order to dissociate NGH.

In addition, according to the drain tower apparatus for regasifying natural gas hydrates according to the present invention, it is possible to secure a drainage path to smoothly drain the hot water sprayed through the nozzle and the aqueous solution discharged from the NGH.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a conventional hold and control system; FIG.
FIG. 2 is a view showing a conventional NGH transportation line; FIG.
3 is a conceptual view showing a conventional NGH cargo hold mounting section;
4 is a perspective view of a drain tower device for regasification of natural gas hydrates according to the present invention;
5 is a conceptual view showing a partial cross-sectional view of the drain tower apparatus according to FIG. 4;
FIG. 6 is a detailed configuration diagram of the drain tower device according to FIG. 4; FIG.
7 is a sectional view of a cargo hold having a drain tower device for regasification of natural gas hydrate according to the present invention;
8 is a schematic view of a natural gas hydrate regeneration system including a drain tower device for regasification of natural gas hydrates according to the present invention;

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 4 is a perspective view of a drain tower apparatus for regasifying natural gas hydrates according to the present invention, FIG. 5 is a conceptual view showing a partial cross section of the drain tower apparatus according to FIG. 4, And FIG. 7 is a sectional view of a cargo hold provided with a drain tower device for regasifying natural gas hydrates according to the present invention.

4 to 7, a drain tower device 200 for regasification of natural gas hydrates according to the present invention relates to a drainage device for a cargo hold having a natural gas hydrate loaded therein, (Hot water) and NGH solution (water) dissociated from the supplied heat are continuously discharged to the outside without stagnation in the cargo hold. In order to dissociate NGH, the hot water sprayed and the NGH dissociation solution are continuously discharged It has a function of heating around the drainage channel and heating it to prevent freezing around the drainage.

The drain tower device 200 is for securing a drain line so that hot water as a heat source to be supplied into the NGH tank (hold) and water dissociated from NGH can be smoothly drained.

The drain tower device 200 is a heating tube 210c that heats ethylene glycol (antifreeze) stored in the inside or outside of a ship through a heat exchanger and supplies the heated ethylene gas to a drain tower installed in an NGH cargo hold to support a drain tower Circulates and heats the periphery of the heating tube 210c to dissociate the NGH and prevent the drainage path from freezing.

In this case, the plurality of heating tubes 210c are arranged in a concentric manner to prevent NGH in the cargo hold 600 from coming into the vicinity of the drain pump 230 or the water pump, and the NGH dissociation number + And is arranged so as to be able to stand on the drain pump installed at the lowest stage.

The drain tower unit 200 includes a heating tube unit 210, a water pump 230 and a base unit 250. The base unit 250 has a cylindrical shape and is fixed to the bottom of the cargo hold (Installed).

The heating tube unit 210 includes a plurality of U-shaped heating tubes 210c each having a longer length than the diameter of the heating tube unit 210 and having an inlet 210a and an outlet 210b through which the antifreeze passes, The upper portion 250b of the base portion 250 has a predetermined gap which is large enough for NGH or NGH particles to pass therethrough so that the adjacent heating tube 210c and the NGH dissociation water Is coupled vertically with the circumference of the upper portion (250b) having a predetermined diameter (D) to such an extent as to be able to install the fastener (230).

The upper portion 250a is formed with a plurality of through holes 250c and the upper portion 250a is formed with a plurality of through holes 250c, And the tube 210c is supported and fixed to the base portion 250. [

The lower portion 250a is formed as an empty space and serves to pass the heating tube 210c drawn in and out from the upper portion 250b.

The drain tower device 200 circulates an anti-freeze agent such as ethylene glycol through a U-shaped heating tube 210c as an intermediary medium, circulates through the heating tube 210c so as to dissociate the natural gas hydrate, ).

The distance d1 between the inlet flow path of the U-shaped heating tube 210c or the inlet 210a and the outlet flow passage 210b is equal to the distance d2 between each U-shaped heating tube 210c So that the openings of the heating tube portion 210 are all spaced apart from each other.

The lower portion of the U-shaped heating tube 210c, which is accommodated in the lower portion 250a, is formed into a curved shape 210e and is not in contact with the bottom portion of the lower portion 250a, thereby improving thermal efficiency .

The base part 250 fixes the water pump 230 to the upper part 250b and drains the mixed solution of the hot water and the dissociated water supplied through the dissociation reaction to the outside of the cargo hold through the pipe connected to the water pump 230. [

The drain tower device 200 bundles the heating tube part 210 with a supporting means 260 such as a band-like band and a tie so that the U-shaped heating tubes 210c are vertically installed at regular intervals.

In addition, the hold 600 has a plurality of drain tower devices 200 therein to drain the mixed solution of hot water and dissociated water supplied to the outside of the cargo hold according to the dissociation reaction.

The heating tube unit 210 includes a plurality of injection holes 210a connected to the water pump 230 and a plurality of outflow holes 210b integrated with the plurality of injection holes 210a. The tube 210c can be efficiently heated.

8 is a configuration diagram of a natural gas hydrate regeneration system including a drain tower device for regasifying natural gas hydrates according to the present invention.

Referring to FIG. 8, first, a plurality of spray nozzles 318 for dissociating NGH are attached to an upper portion of a drain tower 314 including a base portion 250 and a heating tube portion 210.

Hereinafter, a method for regenerating natural gas hydrate having a drain tower device will be described in detail.

The water stored in the water tank 315 is supplied to the heat source 320 such as external steam or gas and the heat exchanger 316 to dissociate the NGH storage tank 600 or the solid state NGH loaded in the cargo hold, (About 80 ° C) and then supplied to a plurality of spray nozzles 318 through a pipe connected to the water pump 317 to spray or spray the hot water onto the NGH.

The NGH is dissociated by the hot water and mixed water of the hot water and the dissociated water becomes high on the bottom or bottom of the NGH storage tank 600 and also inside the heating tube part 210 which is a kind of wall of the drain tower 314. [

The water pump 230 of the drain tower device 200 discharges the mixed water from the NGH storage tank 600 through the connected discharge pipe and the mixed water through the water pump 319 connected in series with the discharge pipe And is collected and stored in the water tank 315 again.

The antifreeze liquid in the antifreeze storage tank 311 such as ethylene glycol is heated through the heat source 320 and the heat exchanger 312 by about 80 ° C. and the heated antifreeze liquid is supplied to the water pump 313, And is supplied to the plurality of injection ports 210a of the heating tube portion 210 through the pipe.

The heated antifreeze is recovered through a return pipe to the antifreeze storage tank 311 and then stored in the antifreeze storage tank 311 after the antifreeze which has been cooled through the flow path of the heating tube 210c and the discharge port 210b.

Here, the recovery pipe connected to the antifreeze storage tank 311 is connected to a plurality of outlets 210b of the heating tube unit 210. [

Therefore, the mixed water that has been accumulated in the drain tower apparatus 200 by the heated heating tube unit 210 can be reused without being frozen and prevented from freezing and clogging of the spray nozzle 318 installed close to the wall of the drain tower 314 can do.

Then, NGH dissociation gas is generated and the gas is input to the water separator 324 through the gas delivery pipe and valve 322 provided in the NGH storage tank 600, and the water is removed from the water separator 324 The gas is delivered to the gas compressor (323) to increase the pressure of the gas and transfer it to an external supply source.

The valve 322 can be turned on and off by a control device (not shown), and a valve 322 and a safety valve 321 are installed in parallel with the valve 322 in the gas delivery pipe, The safety valve 321 is turned on to discharge the gas to the outside storage tank or the atmosphere, and the valve 322 is closed and does not operate.

On the other hand, when the gas pressure is within the tolerance, the safety valve 321 is turned off and the valve 322 is on / off controlled by the control device.

200: drain tower device 210: heating tube part
210a: Inlet port 210b: Outlet
210c: Heating tube 230: Water pump
250: base part 250a: lower part
250b: upper portion 260: support means

Claims (8)

CLAIMS 1. A drain tower apparatus for a drainage system of a cargo hold having a natural gas hydrate loaded therein,
A base portion having a cylindrical shape and installed at the bottom of the cargo hold; And
Shaped U-shaped heating tube having an inlet port and an outlet port and having a length greater than the diameter of the U-shaped heating tube. Each U-shaped heating tube is connected to a U- And a heating tube portion disposed perpendicularly to the base portion and having a diameter formed on a base portion having a diameter so as to have a water pump at an upper portion of the base portion so as to pass therethrough, Tower device.
The method according to claim 1,
The base portion is formed as an upper portion and a hollow space for supporting and fixing a flow path through which a U-shaped heating tube is drawn or drawn to the base portion, and a through- And a drain tower unit for regasifying the natural gas hydrate.
The method according to claim 1,
Wherein the heating tube portion is formed by a plurality of inlets connected to the water pump and a plurality of outlets integrated with the plurality of inlets, and the antifreeze storage tank is heated by the heating tube to regenerate the natural gas hydrate. .
The method according to claim 1,
Wherein the heating tube portion circulates the medium in a U-shaped heating tube, and the distance between the inlet flow path of the U-shaped heating tube and the outlet flow path is the same as the distance between each U- Drain tower device for anger.
5. The method of claim 4,
Wherein the medium is ethylene glycol heated to dissociate the natural gas hydrate and to prevent water supplied from the outside from being frozen.
The method according to claim 1,
Wherein the base portion has a water pump at an upper portion thereof and drains the mixed solution of hot water and dissociated water supplied through the dissociation reaction to the outside of the cargo hold through a pipe connected to the water pump. Device.
The method according to claim 1,
Wherein the base portion binds the heating tube portion with a strip-shaped supporting means so that the U-shaped heating tubes are vertically installed at regular intervals.
The method according to claim 1,
Wherein the cargo hold has a plurality of drain tower units therein to drain a mixed solution of hot water and dissociated water supplied from the outside to the outside of the cargo hold.

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