JPS60241902A - Supply device of cryogenic medium - Google Patents

Abstract

PURPOSE:To simplify equipment and to utilize effectively the cold heat of a cryogenic medium by allowing a liquid to be cooled to effectively absorb the cold heat of the cryogenic medium while preventing the generation of interfacial blocks, and utilizing the agitating action of bubbles of the cryogenic medium vaporized in the liquid to be cooled. CONSTITUTION:Liquefied natural gas spouted from a nozzle 16A is surrounded with natural gas flowing out from an outlet port 17A to intercept the direct contact of liquefied natural gas with seawater 12. Accordingly, the generation of interfacial blocks in a crystallization kettle 11, especially in the vicinity of the nozzle 16A, can be prevented. Besides, since liquefied natural gas is ejected directly into the liquid phase of the seawater 12 in the crystallization kettle 11, the cold heat, namely latent and sensible heat, is absorbed directly into the seawater 12. Consequently, the cold heat of the liquefied natural gas can be effectively utilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an apparatus for supplying a cryogenic medium, and particularly to an apparatus for supplying cryogenic LNG (liquefied natural gas) to seawater for the purpose of seawater desalination.

[Background Art] LNG is imported at an extremely low temperature (-181.5°C) and is used after being vaporized by heat exchange with seawater.

In seawater desalination using LNG cold energy, a technology is already known in which ice is crystallized in seawater using the heat of vaporization of LNG, and the ice is separated from seawater, washed, and melted to produce fresh water.

FIG. 1 shows a conventional device for supplying LNG to seawater. In this figure, seawater 2 as a liquid to be cooled is stored in a crystal canister l as a storage canister, and this seawater 2 is fed by an agitator. 3 and circulated by the crystal tank circulation pump 4, LNG is dispersed from the gas phase of the crystal tank 1 through the LNG introduction pipe 5 onto the liquid phase surface of the seawater 2, and the LNG is dispersed.
G is drawn into the seawater 2 being stirred, and after taking heat from the seawater 2 and vaporizing it, it rises inside the crystal can 1 and flows into the gas heater (not shown) through the gas phase communication pipe 6. can l
The seawater 2 inside is cooled by LNG and crystallized to form a slurry in which fine ice crystal grains are suspended, and this slurry is transferred to a melting tank (not shown) via a slurry outlet pipe 7.

However, in such conventional methods and devices, L
Since the NG is dispersed from the gas phase of the crystal can 1 to the surface of the seawater 2, a stirrer 3 and a crystal can circulation pump 4 are required, and the overall equipment becomes large and the energy required for operation is large. Ta. In addition, LNG in the gas phase
As a result, the temperature of the gas phase decreases, which is disadvantageous from the viewpoint of vaporizing LNG, and the effective use of latent heat and sensible heat of LNG is difficult.
However, it is not always possible to effectively utilize the cold energy of LNG, as it is accompanied by the risk of a steam explosion phenomenon and is prone to interfacial blocks (ice blowing).

Moreover, a similar situation may occur not only when LNG is supplied to seawater, but also when a cryogenic medium other than LNG is supplied to a cooled liquid other than seawater.

[Object of the Invention] An object of the present invention is to provide a cryogenic medium supply device that has simplified equipment and is capable of effectively utilizing the cold energy of the cryogenic medium.

[Structure of the Invention] Therefore, the present invention provides a nozzle for spouting a cryogenic medium into the internal liquid phase of a container housing a liquid to be cooled, and
A non-cryogenic fluid outflow "1" is placed around this nozzle to prevent direct contact between the cryogenic medium ejected from the nozzle and the liquid to be cooled in the container, thereby preventing the occurrence of interface blocks. By effectively absorbing the cold heat of the cryogenic medium into the liquid to be cooled, and by utilizing the stirring action of the bubbles of the cryogenic medium vaporized in the liquid to be cooled, it is possible to eliminate the need for conventional stirring devices. , which aims to achieve the above-mentioned [Objective 1].

[Explanation of Examples] Embodiments of the present invention will be described below based on the drawings.

FIG. 2 shows a cryogenic medium supply device according to the present invention.
An embodiment is shown in which the present invention is applied to a crystal can of a seawater desalination device using cold energy. In the figure, a crystal can 11 serving as a storage can accommodates seawater 12 as a liquid to be cooled, and a can bottom 11A of the crystal can 11 is provided with communication between the inside and outside of the can, as shown in an enlarged view in FIG. A nozzle attachment tube 13 is attached, and a support flange 14 is provided at the end of the nozzle attachment tube 13 on the outside of the can. A nozzle 16 having a nozzle flange 15 on the base end side is inserted into the nozzle mounting pipe 13 from the outside of the can, and a natural gas as a non-cryogenic flow path is provided in the gap between the nozzle mounting pipe 13 and the nozzle 16. (NG) Outflow wave path 1
7 is formed, and one end of a natural gas reflux pipe 18 is communicated with this natural gas flow passage 17. The other end of the natural gas reflux pipe 18 is connected to the gas phase part in the crystal can 11 via the compression Ia 19 and the mist separator 20, and the liquid component of the natural gas in the gas phase is removed by the mist separator 20. The natural gas is then pressurized by a compressor 19 and introduced into the natural gas outflow channel 17.

The upper end of the natural gas outlet channel 17 is a natural gas outlet 17A serving as a non-cryogenic fluid outlet.
A surrounds the nozzle opening 16A of the nozzle 16. LNG spout from nozzle port 16A and N from outflow a17A
The outflow of G takes place at the same time, and such outflow of NG prevents direct contact between LNG and seawater I2.

The area around the outlet 17A is N
An outlet plate 21 is fixed that generates momentum in the outflow of G. The outlet plate 21 and the nozzle 16 are preferably made of tetrafluoroethylene resin (trade name: Teflon) to prevent freezing of these parts.

Further, an LNG introduction pipe 23 as a cryogenic medium introduction pipe having a fixed flange 22 that sandwiches the nozzle flange 15 with the support flange 14 is connected to the nozzle 16, and the support flange 14 and the fixed flange 22 are connected to the nozzle. They are tightened together with bolts 24 with the flange 15 in between.

When LNG, which is a cryogenic medium, is directly injected from the nozzle 16 into the seawater 12, that is, into the liquid phase inside the crystal can 11, LNG
The seawater 12 is cooled by the cold heat of the NG, crystallization occurs, and becomes a slurry, and this slurry is passed through the slurry outlet pipe 25.
On the other hand, the vaporized NG is led out of the can via the gas phase communication pipe 26.

According to this embodiment, the LNG spouted from the nozzle port 16A is surrounded by the NG flowing out from the outlet 17A, thereby blocking direct contact between the LNG and the seawater 12. It is possible to prevent an interface block from occurring near the nozzle opening 16A. In particular, when restricting the outflow of NG in exit play) 21, it is easy to add appropriate momentum to the outflow of NG,
It is easy to reliably block the LNG that is spouted out from the seawater 12.

In addition, since LNG is injected directly into the liquid phase of seawater 12 in crystal canister II, the cold energy of LNG, that is, latent heat and sensible heat, is directly absorbed by seawater 12, making effective use of the cold energy of LNG. is planned. Furthermore, since LNG is not supplied to the gas phase within the crystal can 11, the temperature of the gas phase increases compared to the conventional method, which is advantageous in vaporizing LNG.

However, even if LNG is directly injected into the liquid phase of the seawater 12 at around room temperature, no steam explosion phenomenon will occur, so there is no safety risk.

Furthermore, sufficient stirring action is obtained by the flow of LNG in the seawater 12 and the kinetic energy of the LNG bubbles generated in the seawater 12, so the agitator and circulation pump that were conventionally required are no longer necessary, simplifying the equipment. This has the effect of reducing operating energy.

Furthermore, since the nozzle 16 can be easily replaced from outside the crystal can 11, it is extremely convenient to replace the nozzle 16 when it is worn out, perform maintenance and inspection, etc.

In the above embodiments, the present invention is applied to seawater desalination technology using LNG cold energy, but the present invention is not limited to the above case, and can be applied to LNG vaporization equipment to reduce the size of the equipment. In addition, LNG
It can also be applied when a cryogenic medium other than seawater is supplied to a liquid to be cooled other than seawater. Further, the nozzle 16 is not limited to the can bottom 11A, but may be attached to any can wall located in the liquid phase. Furthermore, the non-cryogenic fluid is not limited to the case where NG is recycled and used, and any fluid other than the cryogenic medium may be used. Heated water or the like may also be used.

[Effects of the Invention] As described above, according to the present invention, it is possible to provide a cryogenic medium supply device that simplifies the equipment and makes effective use of the cold energy of the cryogenic medium.

[Brief explanation of the drawing]

Figure 1 is a front view showing the configuration of a conventional LNG supply device, and Figures 2 and 3 show the cryogenic medium supply device according to the present invention applied to a crystal canister for seawater desalination using LNG cold energy. FIG. 1 is a front view showing the overall configuration of an embodiment and a sectional view showing an enlarged main part. 11... Crystal can as storage can, 12... Seawater as liquid to be cooled, 16... Nozzle, 16A... Nozzle 0.17... NG as flow path for non-cryogenic fluid outflow Outflow channel, 17A...N as a non-cryogenic fluid outlet
G outlet, 18... Seawater introduction pipe as a non-cryogenic fluid introduction pipe, 23... LNG introduction pipe as a cryogenic medium introduction pipe. Agent Patent attorney Minoru Kinoshita (and 1 other person) 0 Figure 1 Figure 2 Apologies, 6 Special opening aGo-241902 (4) Figure 3

Claims (1)

[Claims] (1) A nozzle is provided that spouts a cryogenic medium into the liquid phase of the storage can containing the liquid to be cooled, and the cryogenic medium spouted from the nozzle is directly connected to the liquid to be cooled in the storage can around this nozzle. A supply device for a cryogenic medium, characterized in that an outlet is disposed for discharging a non-cryogenic fluid that prevents contact.