KR101844262B1 - Moisture removing and inerting system for storage tank - Google Patents

Abstract

Disclosed is a storage tank moisture removing and inerting system. According to an embodiment of the present invention, the storage tank moisture removing and inerting system comprises: a compression unit including a plurality of compressors and coolers and compressing a fluid formed by mixing liquefied evaporation gas and nitrogen supplied from a storage tank; a first supply line connecting the storage tank and the compression unit, and making the fluid having passed through the compression unit flow into the storage tank to remove moisture in the storage tank and perform inerting; a nitrogen supply unit supplying nitrogen; and a second supply line connecting the front end of the first supply line and the nitrogen supply unit to have the nitrogen supplied from the nitrogen supply unit join the fluid in the first supply line.

Description

[0001] MOISTURE REMOVING AND INSTING SYSTEM FOR STORAGE TANK [0002]

The present invention relates to a storage tank moisture removal and ingot system.

A vessel for transporting liquefied gas including liquefied natural gas (hereinafter, referred to as 'LNG') may be a membrane for storing a liquefied gas and its boil-off gas (BOG) Type or pressurized storage tank.

The ship may be provided with a fuel gas supply system for converting the pressure, temperature, state, etc. of the liquefied gas evaporated gas or liquefied gas supplied from the storage tank by using a compression unit, a heater, a vaporizer or the like and supplying it to the engine. The vessel may include a low pressure gas injection engine such as a Dual Fuel Disel Electric (DFDE) engine using two or more different fuels as fuel and a high pressure gas injection engine such as a ME-GI engine (Man B & W's Gas Injection engine) have. For example, a fuel gas supply system capable of supplying fuel to a low-pressure and high-pressure gas injection engine compresses the liquefied gas supplied from the storage tank to a high pressure and supplies it to the high-pressure gas injection engine, The evaporated gas can be compressed and then fed to the low pressure gas injection engine.

Conventionally, before the liquefied gas is loaded into the storage tank, a water removal operation for removing moisture from the storage tank and an inert gas injection with an inert gas such as nitrogen are performed. Thereafter, a cooling operation and a gas removal operation for the interior of the storage tank can be performed.

At this time, in order to perform water removal and ingotting in the storage tank, warm-up heaters and related equipment are required, and it takes much time to install and operate them.

As a related art, refer to Korean Patent Laid-Open No. 10-2010-0110500 (published on October 13, 2010).

Korean Patent Laid-Open No. 10-2010-0110500 (disclosed on October 13, 2010)

An embodiment of the present invention is to provide a storage tank water removal and ingot system capable of effectively performing water removal and ingot in a storage tank.

According to an aspect of the present invention, there is provided a compressor comprising: a compressor which compresses a mixed gas of a liquefied gas evaporated gas and nitrogen supplied from a storage tank and includes a plurality of compressors and a cooler; A first supply line connecting the storage tank and the compression unit and introducing the fluid through the compression unit into the storage tank to perform water removal and ingot in the storage tank; A nitrogen supply unit for supplying the nitrogen; And a second supply line connecting the front end of the compression section of the first supply line with the nitrogen supply section and joining the nitrogen supplied from the nitrogen supply section to the first supply line. .

A first control valve disposed between a compressor and a cooler at a last stage of the compression section, and a second control valve branched from the compressor and the first control valve of the first supply line, A second control valve disposed on the branch line, a temperature measurement unit disposed at a downstream end of the junction point of the first supply line and the branch line, for measuring a temperature of the fluid mixed at the junction point, Controlling the first control valve and the second control valve based on the measured temperature to regulate the amount of each fluid mixed at the merging point via the first supply line and the branch line, To a set value.

A first supply line that is branched from the cooler of the first supply line and is connected to the first supply line and the branch line; A surge line connected between a confluence point between the supply lines and a front end of the compression unit, and a surge valve disposed on the surge line.

The second control valve is closed based on at least one of a flow rate measured by the flow rate measurement unit and a difference between the pressures measured by the first pressure measurement unit and the second pressure measurement unit, And a surging control unit for preventing a surge from occurring in the compression unit.

According to another aspect of the present invention, there is provided a compressor comprising: a compressor which compresses a liquefied gas evaporated gas supplied from a storage tank and includes a plurality of compressors and a cooler; A first supply line connecting the storage tank and the compression section and introducing the evaporation gas through the compression section into the storage tank; A first control valve disposed between a compressor and a cooler at a final stage of the compression section; A branch line branched from the compressor of the first supply line and the first control valve and connected to the cooler rear end of the first supply line; A second control valve disposed on the branch line; A temperature measuring unit installed at a downstream end of the joining point of the first supply line and the branch line and measuring the temperature of the mixed gas at the joining point; And a temperature control unit controlling the first control valve and the second control valve based on the measured temperature to adjust a temperature of the evaporation gas to a set value, A storage tank water removal and ingot system may be provided that allows water to be introduced into the storage tank through the first supply line to remove water in the storage tank.

A nitrogen supply unit for supplying nitrogen to the upstream end of the compression unit of the first supply line, and a nitrogen supply unit for connecting the upstream side of the compression unit of the first supply line and the nitrogen supply unit to supply nitrogen supplied from the nitrogen supply unit to the first supply line A second supply line for introducing nitrogen into the storage tank; and a nitrogen supply valve for opening the nitrogen supply valve on the second supply line after nitrogen is removed from the storage tank, And a nitrogen supply controller for allowing the storage tank to perform the ingot by flowing into the tank.

The storage tank water removal and ingot system according to an embodiment of the present invention can effectively perform water removal and ingot in the storage tank.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the claims.

1 shows a storage tank water removal and ingot system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are provided by way of example so that those skilled in the art will be able to fully understand the spirit of the present invention. The present invention is not limited to the embodiments described below, but may be embodied in other forms. In order to clearly explain the present invention, parts not related to the description are omitted from the drawings, and the width, length, thickness, etc. of the components may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

Referring to FIG. 1, a storage tank water removal and ingelling system 100 (hereinafter, also referred to as a system 100) according to an embodiment of the present invention includes a storage tank 110 for storing liquefied gas, A mixture of residual liquefied gas evaporation gas present in the storage tank 110 and nitrogen supplied from the nitrogen supply unit 130 to be described later is used to store the liquefied gas in the storage tank 110 before the liquefied gas is loaded again into the storage tank 110. [ The water removal in the fuel cell 110 and the inertizing operation through an inert gas injection such as nitrogen can be performed. The storage tank 110 may include a membrane type tank, an SPB type tank, and the like, which store the fuel in a liquefied state while maintaining an adiabatic state. The liquefied gas evaporation gas may be any one of LNG (Liquefied Natural Gas), LPG (Liquefied Petroleum Gas), DME (Dimethylether) and Ethane, but is not limited thereto.

Such a storage tank water removal and ingot system 100 can be used for various types of liquefied fuel carriers, liquefied fuel RVs (Regasification Vessels), container ships, general merchant ships, LNG FPSO (Floating, Production, Storage and Off-loading), LNG FSRU Storage and Regasification Unit) and so on.

Specifically, the storage tank water removal and ingot system 100 compresses a mixed gas of the liquefied gas evaporated gas and nitrogen supplied from the storage tank 110, and includes a plurality of compressors 121 and a cooler 122 And a control unit 120 connected to the storage tank 110 and the compression unit 120. The fluid passing through the compression unit 120 is introduced into the storage tank 110 to remove water from the storage tank 110, A nitrogen supply unit 130 for supplying nitrogen and a nitrogen supply unit 130 for connecting the front end of the compression unit 120 of the first supply line L1 to the nitrogen supply unit 130, And a second supply line L3 for joining the nitrogen supplied from the supply unit 130 to the first supply line L1. Although the two-stage compression unit 120 is shown in FIG. 1 for the sake of understanding, the compression unit 120 may be provided more than that.

The storage tank water removal and ingot system 100 further includes a first control valve V1 disposed between the compressor 123 at the last stage of the compression unit 120 and the cooler 124, A branch line L2 branched from the compressor 123 of the first supply line L1 and the first control valve V1 and connected to the downstream end of the cooler 124 of the first supply line L1, A second control valve V2 and a temperature measuring unit installed at a downstream end of the junction point A between the first supply line L1 and the branch line L2 and measuring the temperature of the fluid mixed at the junction point A, The first control valve V1 and the second control valve V2 are controlled based on the temperature measured by the temperature measuring unit 140 so that the first supply line L1 and the branch line L2 are controlled, And a temperature control unit 150 that adjusts the temperature of the mixed fluid at the confluence point A to a set value by adjusting the amount of each fluid to be mixed at the confluence point A described above. The temperature-controlled fluid may be supplied to the storage tank 110 through the first supply line L1 to be used for water removal and ingot operations in the storage tank 110. [

Hereinafter, a process of removing moisture and performing ingot in the storage tank 110 using the system 100 will be described.

The liquefied gas evaporated gas of the storage tank 110 supplied through the first supply line L1 is mixed with nitrogen of the nitrogen supply unit 130 supplied through the second supply line L3 and sent to the compression unit 120 Loses.

Next, the compression section 120 compresses the fluid in which the above-described liquefied gas evaporated gas and nitrogen are mixed. At this time, the compressor 123 and the cooler 124 of the compression unit 120 are alternately arranged to perform compression and cooling.

Next, the temperature measuring unit 140 provided at the end of the junction point A between the first supply line L1 and the branch line L2 is connected to the junction point A between the first supply line L1 and the branch line L2 The temperature of the mixed fluid is measured. At this time, the temperature of the fluid joining to the confluence point A through the branch line L2 without passing through the cooler 124 at the last stage passes through the corresponding cooler 124 through the first supply line L1, Is at a higher temperature than the fluid flowing into the point (A).

The temperature control unit 150 controls the first control valve V1 and the second control valve V2 based on the temperature of the fluid measured by the temperature measurement unit 140 to adjust the temperature of the fluid to the set value. The amount of the fluid flowing into the confluence point A through the branch line L2 by the control of the first control valve V1 and the second control valve V2 flows through the first supply line L1, (A), the temperature of the fluid measured by the temperature measuring unit 140 is increased.

The fluid then flows into the storage tank 110 and is used for water removal and ingotting in the storage tank 110.

In the above-described process, the process of simultaneously removing moisture and performing ingress in the storage tank 110 using the mixed gas of the liquefied gas evaporated gas supplied from the storage tank 110 and the nitrogen supplied from the nitrogen supply unit 130 The water removal and ingot in the storage tank 110 may be sequentially performed.

To this end, the nitrogen supply valve V6 on the second supply line L3 is firstly closed to remove moisture in the storage tank 110 and the opening / closing valve V5 And only the liquefied gas evaporated gas is supplied from the storage tank 110 to the compression unit 120 through the first supply line L1 and is then subjected to the above process and then flows into the storage tank 110 to perform the water removal operation can do.

Next, after the water removal to the inside of the storage tank 110 is completed, the opening / closing valve V5 provided at the rear end of the storage tank 110 of the first supply line L1 is closed and the nitrogen supply valve V6 is opened Nitrogen supplied by the nitrogen supplier 130 flows into the storage tank 110 through the first supply line L1 through the compression unit 120 so that the storage tank 110 is internally . At this time, the nitrogen supply control unit 190 can control the operation of the above-described open / close valves V5 and V6.

On the other hand, when a surge occurs in which vibration and noise are generated in the compressor 123 due to a sudden change in pressure before and after the compression unit 120, fluctuations in flow rate, and other problems, the compression unit 120 is broken .

The storage tank moisture removal and ingot system 100 is connected to the cooler 124 at the last stage of the compression unit 120 and to the junction point of the first supply line L1 and the branch line L2 And a second supply line L1 branched from the cooler 124 and the check valve V3 of the first supply line L1 and branched from the first supply line L1 and the second supply line V2, A surge line L4 connected between the confluence point B between the compression unit 120 and the compression unit 120 and a surge valve V4 disposed on the surge line L4.

The storage tank water removal and ingot system 100 includes a flow rate measuring unit 160 for measuring a flow rate supplied to the compressing unit 120 and a flow rate measuring unit 160 for measuring the pressures of the upstream and downstream stages of the compressing unit 120 The flow rate measured by the first pressure measuring unit 171 and the second pressure measuring unit 172 and the flow rate measured by the flow rate measuring unit 160 and the flow rate measured by the first pressure measuring unit 171 and the second pressure measuring unit 172 And a surge control unit 180 that locks the second control valve V2 based on at least one of the differences in measured pressure and opens the surge valve V4 to prevent the compression unit 120 from generating surge have.

The flow rate measuring unit 160 may be disposed between the connection point C between the first supply line L1 and the surge line L4 and the front end of the compression unit 120. [

The first pressure measuring part 171 is provided at the junction point B between the first supply line L1 and the second supply line L3 and the connection point C between the first supply line L1 and the surge line L4, As shown in FIG.

The second pressure measuring portion 172 may be disposed between the branch point D of the first supply line L1 and the surge line L4 and the check valve V3.

The surge control unit 180 determines whether the flow rate measured by the flow rate measuring unit 160 is less than the set value or the difference between the pressures measured by the first pressure measuring unit 171 and the second pressure measuring unit 172 is less than a set value It is possible to eliminate the surge phenomenon by closing the second control valve V2 and opening the surge valve V4.

This is because a sufficient amount of fluid passing through the cooler 124 at the last end of the compression unit 120 flows to the front end of the compression unit 120 through the surge line L4. At this time, the above-described check valve V3 can prevent the high-temperature fluid passing through the branch line L2 from flowing backward into the surge line L4. The check valve V3 may include, for example, a check valve for allowing fluid to flow in one direction.

Here, the surge protection valve V3 of the first supply line L1 is in an open state. When the surge phenomenon occurs, the surge control unit 180 gradually locks the second control valve V2, Can be controlled while being opened slowly. Only a part of the flow rate is initially sent to the surge line L4, and if the surge phenomenon is not solved, the second control valve V2 is fully submerged, and the surge valve V4 can be fully opened. The second control valve V2 may be controlled through the surge control unit 180 and the temperature control unit 150. However, the second control valve V2 may be controlled by receiving the control value of the surge control unit 180 in order to protect the equipment. The second control valve V2 can be controlled only by the temperature control unit 150 during normal operation except when a surge phenomenon occurs.

After performing the water removal and ingot in the storage tank 110, the cooling operation and the gas removal operation in the storage tank 110 can be performed. Thereafter, the liquefied gas can be loaded into the storage tank 110 have. The liquefied gas evaporated gas of the loaded storage tank 110 may be supplied to the fuel of the engine (not shown) through the compression unit 120 through the first supply line L1 described above. That is, the system 100 according to an embodiment of the present invention utilizing the existing fuel supply system (compression unit, supply line, etc.) can perform water removal and ingotting in the storage tank 110 , It is possible to reduce the cost of manufacturing, purchasing and installing various devices and equipments conventionally required to perform water removal and ingotting in the storage tank.

110: storage tank 120: compression unit
121: compressor 122: cooler
130: nitrogen supply part 140: temperature measurement part
150: temperature control unit 160: flow rate measuring unit
171, 172: pressure measuring section 180: surging control section
190: nitrogen supply control unit L1: first supply line
L2: branch line L3: second supply line
L4: Surge line V1, V2: Control valve
V3: Anti-backflow valve V4: Surge valve

Claims (6)

A compression unit for compressing a liquid mixture of a liquefied gas evaporation gas and nitrogen supplied from a storage tank and including a plurality of compressors and a cooler;
A first supply line connecting the storage tank and the compression unit and introducing the fluid through the compression unit into the storage tank to perform water removal and ingot in the storage tank;
A nitrogen supply unit for supplying the nitrogen;
A second supply line connecting the front end of the compression section of the first supply line and the nitrogen supply section to join the nitrogen supplied from the nitrogen supply section to the first supply line;
A first control valve disposed between a compressor and a cooler at a final stage of the compression section;
A branch line branched from the compressor of the first supply line and the first control valve and connected to the cooler rear end of the first supply line;
A second control valve disposed on the branch line;
A temperature measuring unit installed at a downstream end of the merging point of the first supply line and the branch line and measuring the temperature of the mixed fluid at the merging point; And
Controlling the first control valve and the second control valve based on the measured temperature to adjust the amount of each fluid mixed at the merging point through the first supply line and the branch line, And a temperature controller for adjusting the temperature of the fluid to a preset value. delete The method according to claim 1,
A reverse flow prevention valve disposed between the cooler and the merging point of the first supply line and the branch line,
A surge line branched from the cooler of the first supply line and the check valve and connected between a merging point between the first supply line and the second supply line and a front end of the compression unit,
And a surge valve disposed on the surge line. The method of claim 3,
A flow rate measuring unit for measuring a flow rate supplied to the compression unit,
A first pressure measuring unit and a second pressure measuring unit for respectively measuring the pressure at the front end and the rear end of the compression unit,
Further comprising a surge control unit for closing said second control valve based on at least one of said pressure differences and opening said surge valve to prevent surge from occurring in said compression unit. A compression unit for compressing the liquefied gas evaporated gas supplied from the storage tank and including a plurality of compressors and a cooler;
A first supply line connecting the storage tank and the compression section and introducing the evaporation gas through the compression section into the storage tank;
A first control valve disposed between a compressor and a cooler at a final stage of the compression section;
A branch line branched from the compressor of the first supply line and the first control valve and connected to the cooler rear end of the first supply line;
A second control valve disposed on the branch line;
A temperature measuring unit installed at a downstream end of the joining point of the first supply line and the branch line and measuring the temperature of the mixed gas at the joining point; And
And a temperature control unit controlling the first control valve and the second control valve based on the measured temperature to adjust the temperature of the evaporation gas to a set value,
Wherein the evaporation gas passing through the temperature control unit flows into the storage tank through the first supply line to remove water in the storage tank. 6. The method of claim 5,
A nitrogen supply unit for supplying nitrogen to a front end of the compression unit of the first supply line,
A second supply line connecting the front end of the compression section of the first supply line and the nitrogen supply section and supplying the nitrogen supplied from the nitrogen supply section to the first supply line,
The nitrogen supply valve on the second supply line is opened and the nitrogen supplied by the nitrogen supply unit flows into the storage tank through the first supply line, Further comprising a nitrogen supply control unit for performing an enrichment of the nitrogen in the storage tank.

Images