KR-20260064939-A - RELIQUEFACTION SYSTEM AND SHIP HAVING THE SAME

KR20260064939AKR 20260064939 AKR20260064939 AKR 20260064939AKR-20260064939-A

Abstract

A re-liquefaction system according to an embodiment of the present invention may include: a plurality of compressor units connected in parallel to a plurality of storage tanks through a plurality of distribution lines; a plurality of seawater heat exchangers individually disposed downstream of the plurality of compressor units; a plurality of condensers individually disposed downstream of the plurality of seawater heat exchangers; a plurality of subcooling heat exchangers individually disposed downstream of the plurality of condensers; and a plurality of common rails connecting the plurality of compressor units, the plurality of seawater heat exchangers, and the plurality of condensers. Each seawater heat exchanger is configured to exchange heat between seawater and a fluid compressed by a compressor unit, each condenser is configured to exchange heat between a fluid compressed by at least one compressor unit and a refrigerant compressed by another compressor unit, and each subcooling heat exchanger may be configured to exchange heat between a fluid condensed by at least one condenser and a liquefied gas discharged from at least one storage tank.

Inventors

장대우
최혜성
박종완
이재준
박세현
박청기

Assignees

에이치디한국조선해양 주식회사

Dates

Publication Date: 20260508
Application Date: 20241030

Claims (15)

Multiple compressor units connected in parallel to multiple storage tanks through multiple distribution lines; A plurality of seawater heat exchangers individually arranged downstream of the plurality of compressor units above; A plurality of condensers individually arranged downstream of the plurality of seawater heat exchangers; A plurality of subcooling heat exchangers individually disposed downstream of the plurality of condensers; and It includes a plurality of common rails connecting the plurality of compressor units, the plurality of seawater heat exchangers, and the plurality of condensers. Each seawater heat exchanger is configured to exchange heat between seawater and a fluid compressed by a compressor unit, and Each condenser is configured to heat exchange a fluid compressed by at least one compressor unit with a refrigerant compressed by another compressor unit, and A reliquefaction system configured such that each subcooling heat exchanger exchanges heat between a fluid condensed by at least one condenser and a liquefied gas discharged from at least one storage tank.
In claim 1, The above plurality of common rails are, A first upstream common rail positioned upstream of the plurality of compressor units and connected to the first evaporative gas line of the plurality of storage tanks; A second upstream common rail positioned upstream of the plurality of compressor units and connected to the second evaporative gas line of the plurality of storage tanks; A first downstream common rail disposed downstream of the plurality of compressor units and connected to a first collection line of the plurality of storage tanks; and A reliquefaction system comprising: a second downstream common rail disposed downstream of the plurality of compressor units and connected to a second collection line of the plurality of storage tanks.
In claim 2, A reliquefaction system in which the first evaporation gas lines of the plurality of storage tanks are connected to the first upstream common rail, the second evaporation gas lines of the plurality of storage tanks are connected to the second upstream common rail, the first collection lines of the plurality of storage tanks are connected to the first downstream common rail, and the second collection lines of the plurality of storage tanks are connected to the second downstream common rail.
In claim 2, A plurality of distribution lines are connected in parallel between the first and second upstream common rails and the first and second downstream common rails, and A re-liquefaction system in which the above plurality of compressor units are individually arranged in the above plurality of distribution lines.
In claim 1, Each seawater heat exchanger is a reliquefaction system comprising a fluid passage through which fluid passes and a seawater passage through which seawater passes.
In claim 1, Each condenser is a reliquefaction system comprising a fluid passage through which a fluid passes and a refrigerant passage through which a refrigerant passes.
In claim 6, The above plurality of common rails are, A first intermediate common rail positioned upstream of the refrigerant passage of the plurality of condensers above; A second intermediate common rail positioned downstream of the refrigerant passage of the plurality of condensers; and A re-liquefaction system comprising: a third intermediate common rail positioned upstream of a plurality of compressor units and connected to the second intermediate common rail.
In claim 7, A re-liquefaction system in which a plurality of refrigerant lines are connected in parallel to the first intermediate common rail and the second intermediate common rail, and each refrigerant line is fluidly connected to the refrigerant passage of the corresponding condenser.
In claim 1, Each subcooled heat exchanger is a reliquefaction system comprising a fluid passage through which a fluid passes and a liquid passage through which a liquefied gas passes.
In claim 8, The above plurality of common rails are, A fourth intermediate common rail positioned upstream of the liquid passage of the plurality of subcooled heat exchangers; A fifth intermediate common rail positioned upstream of the fluid passage of the plurality of subcooled heat exchangers; A sixth intermediate common rail positioned upstream of the liquid passage of the plurality of subcooled heat exchangers; A seventh intermediate common rail disposed downstream of the fluid passage of the plurality of subcooled heat exchangers; and A re-liquefaction system comprising: an eighth intermediate common rail positioned upstream of the plurality of compressor units and fluidly connected to the seventh intermediate common rail.
In claim 10, A re-liquefaction system in which the first liquefied gas lines of the plurality of storage tanks are connected to the fourth intermediate common rail, and the second liquefied gas lines of the plurality of storage tanks are connected to the sixth intermediate common rail.
In claim 10, A plurality of fluid lines are connected in parallel to the fifth intermediate common rail and the seventh intermediate common rail, and each fluid line is connected to a fluid passage of a corresponding subcooling heat exchanger, and A re-liquefaction system in which a plurality of liquid lines are connected in parallel to the fourth intermediate common rail, the sixth intermediate common rail, and the plurality of distribution lines, and each liquid line is connected to the liquid line of a corresponding subcooling heat exchanger.
In claim 1, A reliquefaction system in which a refrigerant cycle is configured by connecting at least one compressor unit among the plurality of compressor units, at least one seawater heat exchanger among the plurality of seawater heat exchangers, and at least one condenser among the plurality of condensers in a closed loop.
In claim 1, A reliquefaction system in which a subcooling cycle is formed by connecting at least one compressor unit among the plurality of compressor units, at least one seawater heat exchanger among the plurality of seawater heat exchangers, at least one condenser among the plurality of condensers, and at least one subcooling heat exchanger among the plurality of subcooling heat exchangers in a closed loop.
A vessel comprising a reliquefaction system according to any one of claims 1 to 14.

Description

Reliquefaction System and Ship Having the Same The present invention relates to a reliquefaction system and a ship including the same, and more specifically, to a reliquefaction system capable of efficiently reliquefying evaporated gas generated in a storage tank and a ship including the same. Liquefied gas is gas that has been converted into a liquid state through compression or cooling; as it changes into a liquid state, its volume decreases, making storage and transportation easier. Multi-gas carriers are configured to simultaneously transport various types of liquefied gases, such as low-temperature liquefied gases (propane, ammonia, LPG, etc.) and cryogenic liquefied gases (ethane, butane, carbon dioxide, etc.). A multi-gas carrier has multiple storage tanks for storing various types of liquefied gases. As a portion of the liquefied gas naturally evaporates and vaporizes within each storage tank, evaporated gas is generated. Accordingly, the multi-gas carrier includes a reliquefaction system configured to reliquefy the evaporated gas generated from the multiple storage tanks. The existing reliquefaction system includes three compressor units that compress evaporated gas and three refrigerant cycle units, and by thermally connecting one compressor unit to one refrigerant cycle unit to form a single reliquefaction unit, the existing reliquefaction system includes three reliquefaction units. Of the three reliquefaction units, two operate continuously, and one is used as a spare in case of failure. Each refrigerant cycle unit includes a refrigerant compressor that compresses the refrigerant. As such, existing reliquefaction systems have the disadvantage of increased manufacturing costs due to the inclusion of three refrigerant compressors and three compressor units. In addition, existing reliquefaction systems have the disadvantage that flexible use of the three compressor units and three refrigerant cycles is impossible because each refrigerant cycle is thermally connected only to its corresponding compressor unit, and the three compressor units and three refrigerant cycles are not compatible with each other. The matters described in this background technology section are written to enhance understanding of the background of the invention and may include matters that are not prior art already known to those skilled in the art to which this technology belongs. FIG. 1 is a drawing illustrating a re-liquefaction system according to an embodiment of the present invention. FIG. 2 is an enlarged view of the plurality of compressor units, plurality of seawater heat exchangers, plurality of condensers, and plurality of expansion valves shown in FIG. 1. FIG. 3 is a drawing illustrating a first operational example of a re-liquefaction system according to an embodiment of the present invention. FIG. 4 is a drawing illustrating a second operational example of a re-liquefaction system according to an embodiment of the present invention. FIG. 5 is a drawing illustrating a third operational example of a re-liquefaction system according to an embodiment of the present invention. FIG. 6 is a drawing illustrating a fourth operational example of a re-liquefaction system according to an embodiment of the present invention. Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that in assigning reference numerals to the components of each drawing, the same components are given the same reference numeral whenever possible, even if they are shown in different drawings. Furthermore, in describing the embodiments of the present invention, if it is determined that a detailed description of related known components or functions would hinder understanding of the embodiments of the present invention, such detailed description is omitted. In describing the components of the embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc., may be used. These terms are used merely to distinguish the components from other components, and the essence, order, or sequence of the components is not limited by the terms used. In an embodiment of the present invention, the singular form may include the plural form unless specifically mentioned in the text, and when described as "at least one of A and B and C (or more than one)," it may include one or more of all combinations that can be formed from A, B, and C. And, where it is stated that a component is 'connected', 'combined', or 'connected' to another component, this may include not only cases where the component is directly connected, combined, or connected to the other component, but also cases where it is 'connected', 'combined', or 'connected' due to another component located between the component and the other component. Furthermore, when described as being formed or placed "above or below" each component, "above" or "below" includes not only cases where two components are in dir