KR101801890B1 - Offshore structure - Google Patents

Abstract

A marine structure capable of capturing and storing carbon dioxide is provided. Such a marine structure includes a regeneration module for regenerating the liquefied gas transferred from the liquefied gas storage tank to generate gaseous fuel; A combined power generation unit that generates power using the gaseous fuel; A carbon dioxide capture module for capturing carbon dioxide from the exhaust gas discharged from the combined-cycle power generation unit; And a carbon dioxide pressurizing module for pressurizing the captured carbon dioxide, wherein the pressurized carbon dioxide is heat-exchanged with the liquefied gas to be liquefied, and the liquefied carbon dioxide is stored in a carbon dioxide storage tank.

Description

Offshore structure

The present invention relates to a marine structure capable of combined power generation using liquefied gas as fuel.

Especially, as the environmental regulation condition is strengthened recently, a combined thermal power plant having high performance and reliability with less emission of pollution is often used compared with coal thermal power and nuclear power generation.

Such combined-cycle power generation includes, for example, a gas turbine and a steam turbine. In order to increase the efficiency of the system, the combined cycle power plant generates electricity by rotating the gas turbine with the high-temperature combustion gas generated by burning the fossil fuel first, and thereafter, the combustion gas (exhaust gas) The batch recovery boiler produces steam, which is then used to turn the steam turbine to produce secondary power.

Korean Patent Publication No. 10-2014-0104953 (published on August 29, 2014)

A problem to be solved by the present invention is to provide a marine structure capable of capturing and storing carbon dioxide.

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

According to an aspect of the present invention, there is provided a liquefied gas storage tank for storing a liquefied gas; A carbon dioxide storage tank for storing liquefied carbon dioxide; A regeneration module for regenerating the liquefied gas transferred from the liquefied gas storage tank to generate gaseous fuel; A combined power generation unit including a gas generating module that generates electricity using the gaseous fuel, and a steam generating module that generates steam using waste heat of the exhaust gas generated from the gas generating module and generates electricity using the generated steam; A carbon dioxide capture module for capturing carbon dioxide from the exhaust gas discharged from the combined-cycle power generation unit; And a carbon dioxide pressurizing module for pressurizing the captured carbon dioxide, wherein the pressurized carbon dioxide is heat-exchanged with the liquefied gas to be liquefied, and the liquefied carbon dioxide is stored in the carbon dioxide storage tank.

The carbon dioxide pressurization module further pressurizes the carbon dioxide evaporated in the carbon dioxide storage tank.

Wherein the carbon dioxide pressurizing module includes a first compressor for pressurizing the evaporated carbon dioxide to a first pressure, a second compressor for pressurizing the captured carbon dioxide and carbon dioxide pressurized by the first compressor to a second pressure greater than the first pressure, 2 compressors.

Wherein the regeneration module comprises a recondenser for condensing the liquefied gas, a pressurizing pump for pressurizing the liquefied gas condensed by the recondensor, carbon dioxide pressurized by the carbon dioxide pressurization module, A heat exchanger for exchanging heat with the gas, and a regenerator for regenerating the liquefied gas through the heat exchanger.

Wherein the carbon dioxide capturing module comprises a capturing unit for absorbing carbon dioxide as an absorbent from the exhaust gas discharged from the combined power generation unit, a regeneration unit for regenerating the absorbent by separating the carbon dioxide from the absorbent absorbing the carbon dioxide, And a condenser for condensing the separated carbon dioxide.

The heat source required in the regeneration unit includes steam generated in the steam generation module.

The refrigeration source required in the condenser includes a refrigerant cooled in the regeneration module using the liquefied gas.

The details of other embodiments are included in the detailed description and drawings.

1 is a view for explaining a marine structure according to some embodiments of the present invention.
2 is an exemplary conceptual view of the storage tank of FIG.
3 is an exemplary conceptual diagram of the re-evolving module of FIG.
4 is an exemplary block diagram of the combined power generation unit of FIG.
Figure 5 is an exemplary conceptual view of the CO2 capture module of Figure 1;
6 is an exemplary conceptional view of the carbon dioxide pressurization module of FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

It is to be understood that when an element or layer is referred to as being "on" or " on "of another element or layer, All included. On the other hand, a device being referred to as "directly on" or "directly above " indicates that no other device or layer is interposed in between.

The terms spatially relative, "below", "beneath", "lower", "above", "upper" May be used to readily describe a device or a relationship of components to other devices or components. Spatially relative terms should be understood to include, in addition to the orientation shown in the drawings, terms that include different orientations of the device during use or operation. For example, when inverting an element shown in the figures, an element described as "below" or "beneath" of another element may be placed "above" another element. Thus, the exemplary term "below" can include both downward and upward directions. The elements can also be oriented in different directions, so that spatially relative terms can be interpreted according to orientation.

Although the first, second, etc. are used to describe various elements, components and / or sections, it is needless to say that these elements, components and / or sections are not limited by these terms. These terms are only used to distinguish one element, element or section from another element, element or section. Therefore, it goes without saying that the first element, the first element or the first section mentioned below may be the second element, the second element or the second section within the technical spirit of the present invention.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that the terms "comprises" and / or "comprising" used in the specification are intended to be inclusive in a manner similar to the components, steps, operations, and / Or additions.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. A description thereof will be omitted.

1 is a view for explaining a marine structure according to some embodiments of the present invention.

Referring to FIG. 1, a marine structure according to some embodiments of the present invention includes a storage tank 109, a regeneration module 200, a combined power generation unit 599, a carbon dioxide capture module 800, a carbon dioxide pressurization module 900, And the like.

The storage tank 109 includes a liquefied gas storage tank 100 and a carbon dioxide storage tank 101. The liquefied gas storage tank 100 may store liquefied gas, for example, LNG (liquid natural gas). The liquefied gas is not limited to LNG, and any gas that can be used as fuel for the gas generating module 400 is possible. The carbon dioxide storage tank 101 stores liquefied carbon dioxide (LCO2).

The regeneration module 200 regenerates the liquefied gas (LNG) transferred from the liquefied gas storage tank 100 to generate the gaseous fuel (NG). Further, the boil-off gas (BOG) generated in the liquefied gas storage tank 100 can be compressed and regenerated to generate the gaseous fuel (NG). In addition, seawater can be taken through the seachest and used for regasification, and used seawater can be exported to the outside. Because the seawater is used, the heat source can be used at low cost.

Gas fuel (NG) is regenerated low-temperature, high-pressure gas. The gaseous fuel (NG) can be used to cool the refrigerant (HTCM) to form a cooled refrigerant (LTCM). Therefore, energy required for cooling can be reduced. 3 and FIG. 5, the refrigerant LTCM thus cooled may be used in the carbon dioxide capture module 800 (e.g., the condenser 880 in the module 800).

The combined power generation unit 599 includes a gas generation module 400 and a steam generation module 500.

The gas generating module 400 generates air by compressing the air and burning the gas fuel (NG) with compressed air. The gas generating module 400 can minimize the generation of pollutants by using the gaseous fuel (NG) regenerating the liquefied gas. On the other hand, since air to be used for combustion is in the sea air, it may be necessary to perform pretreatment before being supplied to the gas generating module 400. Here, the pretreatment includes lowering the temperature of the air or removing the humidity of the air.

When the temperature of the air is lowered, the power generation efficiency of the gas generating module 400 can be increased. The power generation efficiency of the gas generator module 400 is inversely proportional to the temperature of the air flowing into the compressor connected to the gas turbine.

Also, it is necessary to remove the humidity of the air, because the gas turbine and the compressor in the gas generating module 400 are vulnerable to droplets and salt. Since the offshore structures are operated in open sea, high humidity and cooling processes can produce droplets. In addition, a significant amount of in-air salinity is also treated by this dehydration process. In addition, in the case of the humidifier, the density is lower than that of the actual dry air, so that the relatively inflow mass flow rate is lowered. Therefore, it is necessary to appropriately dry (dehydrate) the air to be used.

The steam generating module 500 generates steam using the waste heat of the exhaust gas discharged from the gas generating module 400, and generates steam using the generated steam. On the other hand, the steam generated in the steam generating module 500 is transferred to the carbon dioxide capture module 800 and can be used when separating carbon dioxide (or regenerating the absorbent). Therefore, the energy used for separating carbon dioxide can be reduced.

The carbon dioxide capture module 800 captures carbon dioxide (CO2) from the exhaust gas (MTEG) discharged from the combined power generation unit 599. The carbon dioxide capture module 800 may utilize a wet capture method using an absorbent, but is not limited thereto.

The carbon dioxide pressurization module 900 pressurizes the captured carbon dioxide (CO2). Further, the carbon dioxide pressurization module 900 can further pressurize the carbon dioxide (LPGCO2) vaporized in the carbon dioxide storage tank 101. [ Thus, the pressurized carbon dioxide (HPGCO2) is liquefied by heat exchange with the liquefied gas (LNG), and the liquefied carbon dioxide (LCO2) is stored in the carbon dioxide storage tank 101. [

Although not shown separately in FIG. 1, it is apparent that the sea structure according to some embodiments of the present invention includes a pump and a compressor valve necessary for liquid / gas transportation and operation.

2 is an exemplary conceptual view of the storage tank of FIG.

Referring to FIG. 2, the storage tank 109 includes a liquefied gas storage tank 100 and a carbon dioxide storage tank 101.

The storage tank 109 includes a liquefied gas storage tank 100 and a carbon dioxide storage tank 101. The liquefied gas storage tank 100 may store liquefied gas (e.g., LNG). The liquefied gas storage tank 100 provides the liquefied gas to the regeneration module 200 using an internal pump. The boil-off gas generated in the liquefied gas storage tank 100 is also provided to the regeneration module 200.

The carbon dioxide storage tank 101 stores liquefied carbon dioxide (LCO2).

In the carbon dioxide storage tank 101, evaporated carbon dioxide (LPGCO2) may be generated. The evaporated carbon dioxide (LPGCO2) may be supplied to the carbon dioxide pressurization module 900 to be pressurized / liquefied and become liquefied carbon dioxide (LCO2) again.

3 is an exemplary conceptual diagram of the re-evolving module of FIG.

3, the regeneration module 200 includes a low pressure compressor 213, a high pressure compressor 215, a recondenser 220, a pressurization pump 230, a cooling medium cooler 235, A regenerator 237, a regenerator 240, a temperature controller 700, and the like.

The low pressure compressor 213 compresses the boil-off gas generated in the liquefied gas storage tank 100 to the first pressure to generate the first compressed gas IPBOG. The high pressure compressor 215 compresses the first compressed gas IPBOG to a second pressure greater than the first pressure to produce a second compressed gas HPBOG.

The first valve (V1) is disposed on the line connecting the low-pressure compressor (213) and the recondenser (220). The second valve (V2) is disposed on a line connecting the low-pressure compressor (213) and the high-pressure compressor (215).

On the other hand, when the liquefied gas is loaded (unloaded) into the liquefied gas storage tank 100, the boil-off gas may be excessively generated. In this case, the high-pressure compressor 215 may be used selectively. The high-pressure compressor 215 compresses the boil-off gas at a high pressure, thereby minimizing the boil-off gas consumed.

For example, the high pressure compressor 215 can be selectively operated by monitoring the level L1 of the liquefied gas storage tank 100 or the pressure P1 of the unloading line connected to the liquefied gas storage tank 100. Specifically, when the measured level L1 of the liquefied gas storage tank 100 is lower than the first reference value Lc, the first valve V1 is closed and the second valve V2 is opened, (IPBOG) to the high-pressure compressor (215). Alternatively, if the pressure P1 is less than the second reference value Pc, then the first valve V1 is closed and the second valve V2 is closed, if the pressure P1 is lower than the second reference value Pc, on the loading line connecting the liquefied gas storage tank 100 in the liquefied gas transfer line. And the first compressed gas (IPBOG) is delivered to the high pressure compressor (215).

The recondenser 220 condenses the liquefied gas (LNG) and / or the compressed boiling off gas (i.e., the first compressed gas (IPBOG)). The pressurization pump 230 pressurizes the condensed liquefied gas by the recondenser 220.

In the refrigerant cooler 235, the refrigerant (HTCM) and the condensed liquefied gas (HPLNG) are heat-exchanged to generate the cooled refrigerant (LTCM). The cooled refrigerant (LTCM) is provided to the carbon dioxide capture module 800. For example, the cooled refrigerant (LTCM) may be used in the condenser 880 of the carbon dioxide capture module 800.

In the heat exchanger 237, the carbon dioxide (HPGCO2) pressurized by the carbon dioxide pressurization module 900 and the liquefied gas (HPLNG) condensed by the pressurizing pump 203 exchange heat. The pressurized carbon dioxide (HPGCO2) undergoes heat exchange and becomes liquefied carbon dioxide (LCO2). Liquefied carbon dioxide (LCO2) is delivered to the carbon dioxide storage tank (101).

The regenerator 240 also heats the condensed liquefied gas (HPLNG) in the pressurization pump 230. Here, the regenerator 240 can receive the seawater (HTSW) through the seachest and use it for regasification, and can export the seawater (LTSW) to the outside. Because the sea water (HTSW) is used, the heat source can be used at low cost.

Meanwhile, the second compressed gas HPBOG compressed by the high pressure compressor 215 may bypass the re-condenser 220, the pressurizing pump 230, and the regenerator 240.

The temperature controller 700 receives the regenerated gas by the bypassed second compressed gas (HPBOG) and / or the regenerator 240, and generates hot gaseous fuel (NG). The gas generating module 400 receives and uses the gaseous fuel (NG) to generate electricity.

4 is an exemplary block diagram of the combined power generation unit of FIG.

4, the combined power generation unit 109 includes a gas generating module 400 and a steam generating module 500, and the steam generating module 500 includes a steam generator 510 and a steam turbine 520 do.

The steam generator 510 generates steam (STM) and exhausts the exhaust gas (MTEG) by using the waste heat of the exhaust gas (HTEG) provided in the gas generating module (400). The generated steam (STM) is supplied to the steam turbine 520. The steam STM may be supplied to the regeneration section 830 of the carbon dioxide capture module 800 (specifically, the reboiler 870 installed in the regeneration section 830).

The steam turbine 520 generates steam using steam (STM). The condensed water (CDS) generated after the power generation is transferred to the steam condenser 530. The steam condenser 530 cools the delivered condensed water (CDS). At this time, the refrigerant (LTCM) cooled by the refrigerant cooler 235 can be used.

Figure 5 is an exemplary conceptual view of the CO2 capture module of Figure 1;

5, the carbon dioxide capture module 800 includes a trap 810, an exhaust gas separator 820, a desiccant heat exchanger 860, a regeneration unit 830, an absorbent cooler 850, a condenser 880, and the like .

In the capturing unit 810, carbon dioxide in the exhaust gas (MTEG) discharged from the combined power generation unit 599 is absorbed by the absorbent. Here, the absorbent may be, for example, an amine, but is not limited thereto. Although FIG. 5 shows the wet capturing method using an absorbent, it is not limited thereto. Amines, including carbon dioxide, are called rich amines, and relatively less (or free) amines are called lean amines. Therefore, in the capturing unit 810, a lean absorbent is used to absorb carbon dioxide to produce a rich absorbent.

The exhaust gas separator 820 separates the exhaust gas EG and the rich absorbent LTRA. The exhaust gas (EG) is exhausted to the outside of the carbon dioxide capture module 800.

In the desiccant heat exchanger 860, the rich absorbent LTRA and the lean absorbent HTLA provided from the regeneration section 830 exchange heat with each other. Therefore, the low temperature absorbent (LTRA) increases in temperature and becomes a high temperature absorbent (HTRA), and the high temperature absorbent (HTLA) decreases in temperature to become a middle temperature absorbent (MTLA).

The regeneration section 830 regenerates the absorbent by separating carbon dioxide from the hot absorbent HTRA. For example, the regeneration unit 830 is provided with a reboiler 870, which heats the high temperature absorbent HTRA to separate it into carbon dioxide and a lean absorbent (HTLA). The heat source required in the regeneration unit 830 (or the reboiler 870) may utilize the steam (STM) provided in the steam generating module 500.

The condenser 880 condenses the carbon dioxide separated from the regeneration unit 830. Here, the refrigerant source required in the condenser 880 may be a refrigerant (LTCM) cooled using the liquefied gas in the regeneration module 200.

On the other hand, the regenerated lean absorbent (HTLA) becomes an intermediate lean absorbent (MTLA) through the absorbent heat exchanger 880.

Again, the lean absorbent (MTLA) is cooled in absorbent cooler 850. In the absorbent cooler 850, the lean absorbent (MTLA) and the cooled refrigerant (LTCM) heat-exchange with each other to produce a low-temperature lean absorbent (LTLA). The refrigerant source used in the absorbent cooler 850 may be a refrigerant (LTCM) that is cooled using the liquefied gas in the regeneration module 200.

The low temperature lean absorbent (LTLA) is provided in trapping portion 810.

6 is an exemplary conceptional view of the carbon dioxide pressurization module of FIG.

Referring to FIG. 6, the carbon dioxide pressurization module includes a first compressor 910 and a second compressor 920.

The first compressor 910 pressurizes the vaporized carbon dioxide (LPGCO2) to the first pressure.

The second compressor 920 pressurizes the carbon dioxide (CO2) captured by the carbon dioxide capture module 800 and the carbon dioxide (IPGCO2) pressurized by the first compressor 910 to a second pressure greater than the first pressure. The pressurized carbon dioxide (HPGCO2) in the second compressor 920 is provided to the regeneration module 200. [ In the heat exchanger 237 of the regeneration module 200, the pressurized carbon dioxide (HPGCO2) exchanges heat with the liquefied gas. As a result, the pressurized carbon dioxide (HPGCO2) becomes liquefied carbon dioxide (LCO2). The liquefied carbon dioxide (LCO2) is stored in the carbon dioxide storage tank (101).

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

100: Liquefied gas storage tank
101: Carbon dioxide storage tank
200: Reassembly module
400: gas generating module
500: steam generator module
599: Combined power generation unit
800: CO2 capture module
900: CO2 pressurization module

Claims (8)

A regeneration module for regenerating the liquefied gas transferred from the liquefied gas storage tank to generate gaseous fuel;
A combined power generation unit that generates power using the gaseous fuel;
A carbon dioxide capture module for capturing carbon dioxide from the exhaust gas discharged from the combined-cycle power generation unit; And
And a carbon dioxide pressurizing module for pressurizing the captured carbon dioxide,
Wherein the pressurized carbon dioxide is introduced into the regeneration module and is liquefied by heat exchange with the liquefied gas inside the regeneration module and the liquefied carbon dioxide is stored in a carbon dioxide storage tank. The method according to claim 1,
Wherein the carbon dioxide pressurization module further pressurizes the carbon dioxide evaporated in the carbon dioxide storage tank. The method of claim 2, wherein the carbon dioxide pressurization module
A first compressor for pressurizing the evaporated carbon dioxide to a first pressure,
And a second compressor for pressurizing the captured carbon dioxide and the carbon dioxide pressurized by the first compressor to a second pressure greater than the first pressure. The method of claim 1,
A recondenser for condensing the liquefied gas,
A pressurizing pump for pressurizing the liquefied gas condensed by the recondenser,
A heat exchanger in which the carbon dioxide pressurized by the carbon dioxide pressurization module and the liquefied gas condensed by the pressurization of the pressurizing pump are heat-
And a regenerator for regenerating the liquefied gas passing through the heat exchanger. The method of claim 1, wherein the carbon dioxide capture module
A capturing unit for absorbing carbon dioxide as an absorbent from the exhaust gas discharged from the combined power generation unit;
A regeneration section for regenerating the absorbent by separating the carbon dioxide from the absorbent absorbed by the carbon dioxide,
And a condenser for condensing the carbon dioxide separated from the regeneration section. 6. The method of claim 5,
Wherein the heat source necessary for the regeneration unit includes steam generated from the steam generator module of the combined power generation unit. 6. The method of claim 5,
Wherein the refrigerant source necessary for the condenser includes a refrigerant cooled by the liquefaction gas in the re-evaporation module. The method according to claim 1,
The combined power generation unit includes a gas generation module, and a steam power generation module that generates steam using waste heat of the exhaust gas generated from the gas power generation module and generates electricity using the generated steam.

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