JPH1030094A - Transporting system for cold of lng - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold transporting system, capable of efficiently sending the cold of LNG from a receiving base to a remote cold consuming zone. SOLUTION: An LNG receiving base is equipped with a heat exchanger 4 as an evaporator for gasifying an LNG, a regenerating apparatus 10 for taking out a cold from the heat exchanger 4 and accumulating the cold, a transported refrigerant heating pipe 12 for liquefying a transported refrigerant gas sent from a cold consuming zone by the cold of the regenerating apparatus 10 and a compression transfer pump 13 for raising the pressure of the liquefied refrigerant by the transported refrigerant heating tube 12 and transporting the liquefied refrigerant to the cold consuming zone. On the other hand, the cold consuming zone is furnished with an evaporator 16 for taking out a cold by jetting the transformed refrigerant from a nozzle 18 and gasifying it and a regenerating apparatus 22 for carrying out heat exchange by the evaporator 16 and accumulating the cold. The cold is sent to each cold user from the regenerating apparatus 10 by a refrigerant transfer pipe 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for converting the heat of LNG into L
L for transferring from the NG base to a cold heat consuming area for application to district cooling, freezing warehouses, snowmaking equipment for artificial ski resorts, etc.
NG cold heat transfer system.

[0002]

2. Description of the Related Art The cold heat of LNG is only partially used directly for reliquefaction of evaporated LNG (boil-off gas) in an LNG receiving terminal and for a cold source of a freezing warehouse in an area adjacent to the receiving terminal. Most of them (about 70%) are simply discarded by seawater in the evaporator, and are currently not used effectively.

[0003]

The cold energy of LNG can be widely used as a cold source for district cooling and freezing warehouses, for low-temperature crushing of waste such as rubber tires and plastics, and for freezing and fine grinding of food materials. there is a possibility. However, the reason that these technologies are hardly used in practice is that there is no engineering means for transferring cold generated when evaporating LNG to a remote cold heat consuming area.

[0004] That is, the consumption area utilizing the cold heat of LNG is generally distant from the receiving base, and if the refrigerant cooled by the cold heat of LNG is to be transferred as it is by pipes or the like, it is difficult to transfer the refrigerant to the pipes. Most of the cold heat is lost by heat input, and the loss increases with distance. Attempting to transfer the cooling medium by truck or the like is costly and has no economic significance.

[0005] The present invention solves the above technical difficulties, and
An object of the present invention is to provide an LNG cold energy transfer system for efficiently transferring NG cold energy to an area remote from a receiving base.

[0006]

In order to solve the above problems, the present invention provides an LNG cold heat transfer system having the following configuration.

[0007] That is, at the LNG receiving base, L
An evaporator for gasifying NG, a regenerator for extracting and storing cold heat from the evaporator, a heat exchanger for liquefying a transfer refrigerant gas transferred from a cold heat consuming area by the cold heat of the regenerator, A compression transfer pump for increasing the pressure of the refrigerant liquefied by the exchanger and transferring the refrigerant to a cold heat consuming area.

On the other hand, in a cold heat consuming area, an evaporator that takes out cold heat by injecting a transfer refrigerant from a nozzle and gasifying it, and a regenerator that exchanges heat with the evaporator and stores the cold heat. Prepare.

The low-boiling refrigerant having a boiling point of -30.degree. C. to 30.degree. C. is preferably used as the refrigerant to be used in the LNG cryogenic heat transfer system according to the present invention. In addition, it is preferable to use a slurry composed of a low-viscosity medium and fine powder as a cold storage material for the regenerator placed at the LNG receiving terminal and the cold heat consuming area.

[0010] The LNG cold heat transfer system of the present invention has the above-mentioned configuration. At the receiving station, the cold heat obtained by the LNG evaporator is transferred to and stored in the regenerator by a liquid having a low freezing point. The cold energy of the regenerator liquefies the transferred refrigerant gas transferred from a remote cold heat consuming area. The liquefied transfer refrigerant is transferred at a pressure higher than the vapor pressure, and is transferred to the cold heat consuming area without gasification.

When this transferred refrigerant liquid is gasified by injecting it through a nozzle into an evaporator placed in a cold heat consuming area, the inside of the evaporator is cooled by the latent heat of evaporation of the refrigerant. By storing this cold heat in the cool storage device on the consumption area side, the cold heat can be extracted according to the user's need.

That is, the cold heat transfer system of the present invention absorbs the cold heat of LNG generated at the receiving terminal by liquefying the transfer refrigerant flowing to and from the pipe connecting the cold heat consuming area, and the transferred cold liquid is transferred to the cold heat consuming area. The cold heat is recycled by gasification. Thus, the system of the present invention realizes efficient cold heat transfer.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an LNG cold heat transfer system according to the present invention will be specifically described based on one embodiment shown in the drawings. In the figure, 1 is an LNG storage tank, 2 is LN
G discharge pump, 4 heat exchanger for gasifying LNG, 10
Are regenerators that store LNG cold energy, and are installed at LNG receiving terminals.

The heat exchanger 4 has a heat transfer tube 5, LNG is led from the LNG storage tank 1 through the LNG pipe 3, gasified, and sent out to the LNG use facility via the evaporative gas pipe 6. The regenerator 10 includes a refrigerant-side heat transfer tube 11, and a medium is circulated through the refrigerant-side heat transfer tube 11 by the refrigerant circulation pump 9 via the refrigerant tubes 7 and 8.

The regenerator 10 has a transfer refrigerant heat transfer tube 12
The refrigerant is circulated by the compression transfer pump 13 between the transfer pipe (forward) 14-1 and the evaporator 16 of the cold heat consuming area described later via the transfer pipe (return) 15-1. Reference numeral 27 denotes a stirrer for stirring the regenerator material in the regenerator 10.

Reference numeral 16 denotes an evaporator in which a heat transfer tube 17 is provided. Reference numeral 22 denotes a regenerator, and the evaporator 16 and the regenerator 2
2 is installed in the cold heat consuming area. The evaporator 16 has LNG
Transfer piping 14-1, 1 from the regenerator 10 at the receiving base
A transfer pipe (outward) 14-2 and a transfer pipe (return) 15-2 communicating with 5-1 are guided, and the transfer pipe 14-2 is provided with a nozzle 18 for injecting the introduced transfer refrigerant liquid. Have been.

In the heat transfer tube 17, a regenerator material in a regenerator 22 is circulated by a refrigerant circulation pump 20 via refrigerant tubes 19 and 21. A heat transfer tube 23 is provided in the regenerator 22, and a medium is transferred by a refrigerant transfer pump 26 to a cold heat user via the refrigerant transfer tubes 24 and 25.

The illustrated LNG cold and heat transfer system has the above configuration. At the LNG receiving terminal, LNG is stored at -162 ° C. in the LNG storage tank 1 and gasified by the heat exchanger 4 when used. Is done. That is, in the heat exchanger 4, the temperature of the LNG is increased by the medium circulating through the refrigerant pipes 7 and 8 and the refrigerant-side heat transfer pipe 11, and the temperature is increased by gasification. As a circulating medium for LNG gasification, ethanol, methanol, or the like having a low freezing point is used.

Through the medium, LNG cold heat is stored in the regenerator 10
Is stored in The regenerator material used in the regenerator 10 may be ferrite, magnetite, zirconia, or other low-viscosity ethanol or methanol whose flowability has been increased by a dispersant, or a slurry obtained by mixing water with the dispersant to increase the heat capacity. Use

As described above, LN is provided inside the regenerator 10.
G A low temperature of -100 to -80C is obtained by cold heat. In the regenerator 10, on the other hand, the refrigerant gas transferred from the cold heat consuming area can be heat-exchanged with the regenerator material to be liquefied. That is, a part of the cold energy of the regenerator 10 is used for liquefaction of the transferred refrigerant gas.

The heat lost during the transfer of the transferred refrigerant from the regenerator 10 at the LNG receiving terminal to the cold heat consuming area is proportional to the difference with the outside air temperature, so that if the boiling point of the refrigerant is close to the outside air temperature, In addition, the heat loss is reduced and the transport heat efficiency is improved.

Therefore, it is desirable that the transfer refrigerant is a substance having a low boiling point, a relatively normal temperature and a low vapor pressure. Examples of such a refrigerant include HCFC (boiling point: -12 ° C., vapor pressure: 3.9 kgf / cm ² , molecular formula: CF ₃ CHClF), HFC
(Boiling point -24 ° C, vapor pressure 6.1 kgf / cm ² , molecular formula CH
F ₂ CH ₃ ). In addition, if the transferred refrigerant liquid is transferred to the consuming area at a pressure higher than the vapor pressure of the transferred refrigerant, the liquid state can be maintained regardless of the heat loss during the transfer.

When the transferred refrigerant liquid thus sent to the cold heat consuming area is injected into the low-pressure atmosphere through the nozzle 18 by the evaporator 16, the refrigerant liquid is gasified, and the latent heat of evaporation causes the heat exchange heat transfer tube 17 to flow. Cooling. This cold heat is circulated and transferred to the regenerator 22 through the pump 20 to provide a temperature of 0 ° C to -60 ° C.
Stored at a temperature of ° C. The cold heat of the regenerator 22 in this consuming area can be transferred to each user by the refrigerant transfer pipe 24 as needed by the user.

Thus, according to the transfer system of FIG.
Since the LNG cold energy is converted to liquefied energy of the refrigerant substance and transferred to the cold energy consuming area, the LNG cold energy can be efficiently used in the cold energy consuming area with almost no influence of heat loss in the middle of the refrigerant pipe.

[0025]

As described in detail above, the L of the present invention
According to the NG cold heat transfer system, the cold generated at the LNG receiving base can be transferred to a remote cold heat consuming area by circulating the transfer medium between the LNG receiving base and the regenerator provided in the cold heat consuming area.

Therefore, according to the present invention, LNG which was conventionally discarded in seawater because it could not be transported to a consumption area
Can be used efficiently even in the consuming area away from the receiving terminal. As described above, according to the transfer system of the present invention, it is possible to effectively use LNG cryogenic energy,
It will be possible to supply cold heat to district cooling, freezing warehouses, etc. at low cost.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a cold heat transfer system according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 LNG storage tank 4 Heat exchanger 10 Regenerator 16 Evaporator 18 Nozzle 22 Regenerator

Claims (3)

[Claims] 1. An LNG receiving terminal, comprising: an evaporator for gasifying LNG; a regenerator for extracting and storing cold heat from the evaporator; and a regenerator for transferring the transferred refrigerant gas transferred from a cold heat consuming area. A heat exchanger that liquefies by the cold heat of the vessel, and a compression transfer pump that increases the pressure of the refrigerant liquefied by the heat exchanger and transfers the refrigerant to a cold heat consuming area. An LNG comprising: an evaporator for extracting cold heat by injecting and gasifying; and a regenerator for exchanging heat in the evaporator and storing the cold heat.
Cold heat transfer system. 2. The refrigerant having a boiling point of -30.degree.
The LNG refrigeration heat transfer system according to claim 1, wherein a low-boiling refrigerant of 0 ° C is used. 3. The LNG cold heat transfer system according to claim 1, wherein a slurry composed of a low-viscosity medium and a fine powder is used as a cold storage material for the LNG receiving terminal and the cool storage device located at the cold heat consuming area.