KR20110021526A - Regasification unit of liquefied natural gas - Google Patents

Abstract

PURPOSE: An apparatus for re-gasifying liquefied natural gas is provided to continuously circulate the LNG without stopping a booster pump. CONSTITUTION: An apparatus for re-gasifying liquefied natural gas comprises a gas transfer line(110), a drum(120), a booster pump(130), a vaporizer(140), a circulating line(150), a pressure applying line(170), a fuel supply line(210), and a circulation control line(160). The drum is installed on the gas transfer line and temporarily stores LNG. The booster pump pumps the LNG to a predetermined pressure. The vaporizer vaporizes the LNG, which has been provided from the booster pump. The circulating line controls the flow rate and the pressure of the LNG. The pressure applying line makes the vaporized LNG flow into the drum and pressurizes it. The circulation control line makes the LNG temporarily flow into a storage tank if the temperature of the drum rises by the pumping energy of the booster pump.

Description

Regasification facility of liquefied natural gas {REGASIFICATION UNIT OF LIQUEFIED NATURAL GAS}

The present invention relates to a regasification facility for liquefied natural gas, and more particularly, to a vessel such as a gas carrier carrying liquefied natural gas, or a comprehensive facility for mining, storing, liquefying and vaporizing a gas in a floating state on the sea. The present invention relates to a regasification plant for liquefied natural gas that allows liquefied natural gas to flow smoothly from a suction drum into a booster pump in a floating or stationary gas treatment facility.

In general, liquefied natural gas (Liquefied Natural Gas) is known to be a clean fuel and abundant reserves than petroleum, and its use is rapidly increasing with the development of mining and transport technology.

Liquefied natural gas is a liquid produced when the temperature of methane, the main component of natural gas, is lowered below -163 degrees Celsius under 1 atmosphere. The volume of liquefied liquefied natural gas is 600 minutes of the volume of liquefied natural gas in a standard gas state. It is about 1, and the specific gravity is about 0.47, which is about one half of the crude oil specific gravity.

Because of this, liquefied natural gas has the advantage of being easy to transport and store, but has a very low temperature and is very dangerous in case of leakage, so it is a separate gas made of an insulator (insulation material) in a ship or a floating or fixed gas treatment facility. Transport or storage to storage tanks.

In general, such liquefied natural gas transportation is carried on the land as it is liquefied natural gas in the liquefied natural gas cargo hold, and the unloaded liquefied natural gas is regasified by the liquefied natural gas regasification facility installed on land and then It is transported through gas piping to the customer.

Natural land gas regasification plant is known to be economically advantageous when installed in a place where there is a demand for natural gas because the natural gas market is well formed. However, in the case of natural gas demand destinations where the demand for natural gas is seasonal, short-term or periodic, it is economically disadvantageous to install liquefied natural gas regasification facilities on land due to the high installation cost and management cost.

In particular, if a natural LNG regasification facility is destroyed due to a natural disaster, even if the LNG carrier arrives at the destination with a liquefied natural gas, the existing liquefied natural gas cannot be regasified. Transport of natural gas by means of transport is limited.

Accordingly, for example, a liquefied natural gas regasification facility is provided in a liquefied natural gas carrier to regas a liquefied natural gas at sea, and the natural gas ('NG') obtained through the regasification is landed. Offshore LNG natural gas regasification facilities are being developed.

Such a conventional LNG regasification vessel is equipped with a LNG natural gas regasification facility including a vaporizer for regasification of the LNG stored in the LNG cargo hold, and further includes regasified NG on land demand. In order to supply to the furnace, a pipe connecting device for connecting the pipe of the liquefied natural gas regasification device and the gas pipe of the land demand destination, and a ship position maintaining device for maintaining the position of the ship while the NG is unloaded is provided.

1 is a configuration diagram illustrating a regasification facility of liquefied natural gas according to the prior art.

First, in a manner in which liquefied natural gas is supplied to the engine 10 as a fuel, when natural fuel gas generated in the storage tank 1 cannot satisfy the fuel demand of the engine, the liquefied gas is forced to vaporize the engine. It is to supply fuel gas to (10).

The fuel supply pump 1a inside the storage tank 1 is driven to supply the liquefied gas stored in the storage tank 1 to the vaporizer 2. The gas passed through the vaporizer 2 is introduced into the mist separator 4. Mist separator 4 serves to remove the mist generated in the vaporizer (2). Mist should be removed immediately by using the mist separator (4) because the problem occurs when the engine enters the engine.

And the gas which passed through the mist separator 4 flows into the heating part 6.

The heating unit 6 increases the temperature of the gas passing through the mist separator 4 to the temperature required for operation of the engine, and the temperature and pressure of the gas passing through the mist separator 4 are too low to be used as fuel for the engine. Therefore, the gas is heated and pressurized to be used in the engine 10 through the compressor 8 installed together with the heating unit 6.

On the other hand, it is largely composed of a delivery pump (1b), a suction drum (30) installed on the gas transfer line 20, a booster pump (40) and a vaporizer (50) for sending liquefied natural gas to the land.

A gas transfer line 20 is installed so as to extend from the delivery pump 1b in the storage tank 1 to the demand destination, and the suction drum 30 and the booster pump 40 are sequentially formed on the gas transfer line 20. The carburetor 50 is installed.

The suction drum 30 is a tank that temporarily stores the liquefied natural gas in order to stably supply the liquefied natural gas to the booster pump 40, and pressurizes the inside of the suction drum 30 with nitrogen supplied through the nitrogen supply unit 32 connected thereto. As a result, the transfer to the booster pump 40 is assisted.

The booster pump 40 may control the transfer amount by pumping the liquefied natural gas transferred from the suction drum 30 to a pressure required by the vaporizer 50.

In addition, the vaporizer 50 for vaporizing the liquefied natural gas transferred from the booster pump 40 vaporizes the liquefied gas pumped at high pressure and transfers it to the demand destination.

In addition, the gas transfer line 20 is branched to the rear side of the booster pump 40 and connected to the suction drum 30, and branched to the rear side of the vaporizer 50 so as to be connected to the suction drum 30. Pressing line 70 is installed.

On the gas transfer line 20 between the circulation line 60 and the booster pump 40 and the vaporizer 50, a flow rate and pressure control valve 62 is installed, and the pressure line 70 has a suction drum pressure control valve ( 72) is installed.

Therefore, the transfer of the liquefied natural gas is subjected to a step of temporarily storing the liquefied natural gas stored in the storage tank 1 in the suction drum 30 through the delivery pump 1b.

In addition, with the aid of nitrogen supplied from the nitrogen supply unit 32, the inhalation drum 30 flows the liquefied natural gas into the booster pump 40, and the booster pump 40 pumps the liquefied natural gas to a predetermined pressure, and then the vaporizer. It is vaporized at (50) and sent to demand.

Here, the suction drum 30 initially supplies the liquefied natural gas to the booster pump 40 by supplying the nitrogen supplied from the nitrogen supply unit 32 to the booster pump 40, and if the gas is continuously regasified, the nitrogen supply is The stopped and regasified natural gas is introduced into the suction drum 30 through the pressure line 70 to pressurize the inside of the suction drum 30 instead of nitrogen. In addition, the suction drum pressure regulating valve 72 adjusts the inflow and pressure of the regasified natural gas.

However, according to the prior art, when the liquefied natural gas flows back into the suction drum 30 along the circulation line 60 in the booster pump 40, the pumping energy of the booster pump 40 is introduced into the suction drum 30. As a result, when there is no supply of the liquefied natural gas from the storage tank 1 to the suction drum 30, the temperature of the liquefied natural gas in the suction drum 30 rises, thereby increasing the booster pump (at the suction drum 30 side). There was a problem that the inflow into 40) is not made smoothly.

As described above, when the inflow into the booster pump 40 cannot be smoothly performed on the suction drum 30 side, the booster pump 40 has to be temporarily suspended. In the performance test of the pump 40, it acts as a big constraint. In addition, since the liquefied natural gas is re-introduced only between the booster pump 40 and the suction drum 30, it is difficult to evaluate the connection with the delivery pump 1b.

The present invention has been invented to solve the above problems, its purpose is to increase the temperature in the suction drum due to the pumping energy delivered from the booster pump to facilitate the inflow of liquefied natural gas from the suction drum side to the booster pump side If not, the liquefied natural gas pumped from the booster pump flows into the storage tank instead of the suction drum, and when the temperature in the suction drum decreases after a certain period of time, the liquefied natural gas flows into the suction drum side again without stopping the booster pump. It is to provide a regasification facility of liquefied natural gas to enable the continuous circulation of liquefied natural gas.

In addition, in another object of the present invention, there was a limitation in evaluating the pump performance by continuously liquefied liquefied natural gas in the intake drum having a small size when evaluating the performance of the booster pump before the actual regasification operation, inflow into the storage tank If this can be done, it is possible to provide an accurate performance evaluation without restriction, and to provide a re-gasification facility for liquefied natural gas that can also be linked integrated evaluation between the discharge pump, the suction drum and the booster pump.

In order to achieve the above object, according to the present invention, the gas transfer line for sending the liquefied natural gas from the storage tank to the demand destination, the suction drum installed on the gas transfer line to temporarily store the liquefied natural gas, A booster pump installed at the rear side to pump the liquefied natural gas to a predetermined pressure, a vaporizer to vaporize the liquefied natural gas supplied from the booster pump, and branched from the gas transfer line between the booster pump and the vaporizer to be connected to the suction drum. Circulation line for adjusting the flow rate and pressure of liquefied natural gas, pressurization line branched from the rear side of the vaporizer, connected to the suction drum, and pressurized by introducing the vaporized natural gas into the suction drum, and the storage tank. Fuel supply line and circulation line installed to use liquefied natural gas as engine fuel It is connected to the storage tank is installed to the storage tank and the regasification facility of the liquefied natural gas including a circulation control line for temporarily introducing the liquefied natural gas into the storage tank when the temperature of the suction drum by the pumping energy of the booster pump is provided.

And a three-way valve is installed in the circulation control line may be to select the liquefied natural gas inlet to the suction drum side or the storage tank side.

In addition, performance evaluation can be made by circulating liquefied natural gas through a circulation control line when evaluating the performance of the booster pump before the actual regasification operation.

According to the regasification facility of the liquefied natural gas of the present invention, the inflow of the liquefied natural gas into the booster pump on the suction drum side can be made smoothly, the effect that can be continuously circulated liquefied natural gas without stopping the booster pump have.

In addition, when evaluating the performance of the booster pump before the actual regasification operation, the temperature rises quickly in the small suction drum when liquefied natural gas is circulated to the suction drum. Performance evaluation is possible, and the integrated integrated evaluation between the discharge pump, the suction drum, and the booster pump also has the effect.

Hereinafter, one embodiment of the present invention will be described in more detail with reference to the accompanying drawings so that those skilled in the art can easily practice, but this is only an example, the present invention is limited thereto. It doesn't happen.

2 is a block diagram of a regasification plant of liquefied natural gas according to an embodiment of the present invention.

As illustrated in FIG. 2, the regasification facility of the liquefied natural gas of the present embodiment includes a gas transfer line 110 and a gas transfer line 110 for sending the liquefied natural gas from the storage tank 100 to the demand destination. Suction drum 120 is installed in, the booster pump 130 for pumping the liquefied natural gas to a predetermined pressure, the vaporizer 140 for vaporizing the liquefied natural gas, and for adjusting the flow rate and pressure of the liquefied natural gas Circulating line 150, the pressurizing line 170 to pressurize the inside of the intake drum 120 by the vaporized natural gas, and the liquefied natural gas of the storage tank 100 as the fuel of the engine 200 It may include a fuel supply line 210 is installed to.

Here, the storage tank 100 is a structure for storing liquefied natural gas to be transported in a ship, or a floating or fixed gas treatment facility having a comprehensive facility for mining, storing, purifying, liquefying and vaporizing a gas in a floating state on the sea. It may be a structure for storing the fluid in the.

The gas transfer line 110 may be a line for transmitting the liquefied natural gas sent from the delivery pump 102 in the storage tank 100 to the demand destination.

The nitrogen supply unit 122 which supplies nitrogen to pressurize the inside of the suction drum 120 may be connected to and installed at an initial stage of regasification. The temperature, pressure, and flow rate corresponding to the vaporization factor may be constant. It must be maintained. Therefore, the vaporizer 140 is followed by the measured value measured temperature, pressure, flow rate to a predetermined design value, and as a result, the temperature and pressure is controlled to be kept constant.

And a circulation line 150 branched from the gas transfer line 110 between the booster pump 130 and the vaporizer 140 is connected to the suction drum 120 is installed, the first flow rate control on the circulation line 150 A second flow control valve 154 may be installed on the gas transfer line 110 between the valve 152 and the booster pump 130 and the vaporizer 140 to control the amount of liquefied natural gas discharged.

Each of the first flow regulating valve 152 and the second flow regulating valve 154 may be controlled by opening and closing each valve by a conventional valve control logic circuit capable of adjusting the amount of gas as required.

In addition, the circulation control line 160 may be installed to branch from the circulation line 150 is connected to the storage tank 100 is installed. The circulation control line 160 temporarily converts the liquefied natural gas into the storage tank 100 when the liquefied natural gas does not flow smoothly due to the temperature rise of the suction drum 120 due to the pumping energy of the booster pump 130. It may be to inflow.

Therefore, the three-way valve 162 is installed in the circulation control line 160 at the branch point with the circulation line 150 to select the inflow of the liquefied natural gas to the suction drum 120 side or the storage tank 100 side. The three-way valve 162 may be a solenoid valve.

The pressurizing line 170 is branched from the gas transfer line 110 behind the vaporizer 140 and connected to the suction drum 120 to pressurize the inside of the suction drum 120 during the regasification operation, and is connected to the vaporizer 140. The natural gas vaporized by the gas can be introduced.

A pressure control valve 172 is installed in the pressure line 170 to adjust the pressure of the gas flowing into the suction drum 120.

In addition, the pressure regulating valve 172 and the first flow regulating valve 152 and the second flow regulating valve 154 follow the predetermined design value in the electronic system control circuit so that natural gas can be sent to the demand side. It may have an algorithm that performs temperature control, pressure control, and flow control by receiving the precise measurement values of the temperature, pressure, and flow rate of the input flow rate and the output flow rate, respectively.

Perform valve opening and closing based on predetermined condition values previously stored in a conventional electronic system control circuit (not shown), such as whether the vessel is mooring or anchoring, whether the gas treatment facility is abnormally operated, or whether the boil-off gas is excessively generated. Or the valve opening and closing ratio can be adjusted.

To this end, although not shown in the gas transfer line 110, a pressure gauge and a flow meter may be installed and connected to a signal input terminal (not shown) of the electronic system control circuit.

Meanwhile, a fuel supply line 210 is installed to supply fuel to the engine 200, and the fuel supply line 210 drives the fuel supply pump 104 to vaporize the liquefied gas stored in the storage tank 100. Vaporizer 212 is provided for, and the mist separator 214 may be installed to remove the mist generated in the gas passed through the vaporizer 212.

And the heating unit 216 is installed to heat the gas passed through the mist separator 214, the heating unit 216 to raise the temperature of the gas past the mist separator 214 to the temperature required for the operation of the engine Since the temperature and pressure of the gas passing through the mist separator 214 are very low to be used as fuel of the engine, the gas is heated to be used in the engine 200 through the compressor 218 installed together with the heating unit 216. Pressurize

The operation of the regasification facility of liquefied natural gas having such a structure is performed as follows.

Referring to Figure 2 again, the transmission from the storage tank 100 to the demand destination, the step of temporarily storing the liquefied combustion gas stored in the storage tank 100 to the suction drum 120 through the delivery pump 102 Going through.

In addition, the suction drum 120 needs to pressurize the inside to transfer the liquefied natural gas to the booster pump 130. Accordingly, the inside of the suction drum 120 is pressurized using nitrogen supplied from the nitrogen supply unit 122. do.

The liquefied natural gas transferred from the suction drum 120 is pumped to the required preset pressure in the booster pump 130, and the pumped liquefied natural gas is discharged from the vaporizer 140 to the demand destination.

In this case, when it is necessary to control the amount of liquefied natural gas flowing from the booster pump 130 to the vaporizer 140, the second flow control valve 154 is closed and the suction drum 120 is opened through the first flow control valve 152. Will be reintroduced.

At this time, when the pumping energy from the booster pump 130 is transferred to the suction drum 120 as it is through the liquefied natural gas, the internal temperature of the suction drum 120 is raised to prevent smooth inflow into the booster pump 130. Can be. Therefore, in this case, by introducing the liquefied natural gas heated by the control of the three-way valve 162 into the storage tank 100 through the circulation control line 160, the suction drum that is temporarily stopped the inflow of the liquefied natural gas The internal temperature of 120 can be lowered.

Then, when the internal temperature of the suction drum 120 is lowered, the liquefied natural gas is introduced into the suction drum 120 through the three-way valve 162 again.

Furthermore, when the performance of the booster pump 130 is evaluated before the actual regasification operation, since the temperature rises quickly in the small suction drum 120 during the liquefied natural gas circulation to the suction drum 120, the continuous performance test is limited. Through the circulation control line 160, the inflow into the storage tank 100 can accurately evaluate the performance without the constraints of time and space, it is also possible integrated integrated evaluation between the pump and the suction pump, booster pump.

If the regasification process is continued as described above, the inflow of nitrogen for pressurizing the suction drum 120 is blocked, and the pressure control valve 172 is opened so that a part of the vaporized natural gas passes through the pressure line 170. It is introduced and pressurized to the internal pressure required by the suction drum 120 during the regasification process.

Next, when the regasification process is completed, the liquefied natural gas remaining in the suction drum 120 and the booster pump 130 is reintroduced into the storage tank 100 through the drain line 132.

Therefore, as described above, the liquefied natural gas flows into the booster pump 130 from the suction drum 120 side through the circulation control line 160 smoothly, so that the liquefied natural gas of the booster pump 130 is not stopped. The circulation can be continuous and an accurate performance assessment of the booster pump 130 can be carried out before the actual regasification operation.

As described above as a specific embodiment of the regasification facility of liquefied natural gas according to the present invention, this is only an example, the present invention is not limited to this, it is interpreted to have the broadest range in accordance with the basic idea disclosed herein Should be. Those skilled in the art can easily change the material, size, etc. of each component according to the application field, and can be combined / substituted the disclosed embodiments to implement a pattern of a timeless shape, but this also does not depart from the scope of the present invention will be. It will be apparent to those skilled in the art that various changes and modifications may be readily made without departing from the spirit and scope of the invention as defined by the appended claims.

1 is a configuration diagram for explaining the regasification facility of liquefied natural gas according to the prior art,

2 is a block diagram of a regasification plant of liquefied natural gas according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: storage tank 110: gas transfer line

120: suction drum 130: booster pump

132: drain line 140, 212: vaporizer

150: circulation line 152, 154: first, second flow control valve

160: circulation control line 162: three-way valve

170: pressure line 172: pressure control valve

200: engine 210: fuel supply line

214: mist separator 216: heating part

218: compression unit

Claims (3)

A gas transfer line for delivering liquefied natural gas from a storage tank to a demand destination; A suction drum installed on the gas transfer line to temporarily store liquefied natural gas; A booster pump installed at a rear side of the suction drum to pump liquefied natural gas to a predetermined pressure; A vaporizer for vaporizing liquefied natural gas supplied from the booster pump, A circulation line branched from the gas transfer line between the booster pump and the vaporizer to adjust the flow rate and pressure of the liquefied natural gas installed and connected to the suction drum; A pressurizing line branched from the rear side of the vaporizer, connected to the suction drum, and pressurizing the inside of the suction drum by introducing vaporized natural gas; A fuel supply line installed to use the liquefied natural gas of the storage tank as a fuel of an engine; A circulation control line branched from the circulation line and connected to the storage tank and temporarily introducing liquefied natural gas into the storage tank when the temperature of the suction drum is increased by the pumping energy of the booster pump. Regasification plant of liquefied natural gas comprising a. The method of claim 1, The circulating control line is provided with a three-way valve to re-liquefied natural gas regasification equipment to select the liquefied natural gas inlet to the suction drum side or the storage tank side. The method of claim 1, The regasification facility of liquefied natural gas that can be evaluated by circulating the liquefied natural gas through the circulation control line when evaluating the performance of the booster pump before the actual regasification operation.

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