KR102132085B1 - gas treatment system and offshore plant having the same - Google Patents

Abstract

The present invention relates to a gas treatment system and an offshore structure including the same, which is provided on the offshore structure and receives and processes gas from a gas well, and is a water treatment agent having an adsorption column that adsorbs moisture contained in the gas produced in the gas well. denial; And a liquefaction unit for liquefying the gas from which moisture has been removed, wherein the moisture removal unit comprises: a regeneration gas supply unit that supplies high-temperature regeneration gas to vaporize and separate moisture adsorbed on the adsorption column to the adsorption column; A regeneration gas cooling unit for condensing steam by cooling regeneration gas discharged from the adsorption column together with steam; And a water separation unit for separating the condensed moisture from the regeneration gas, and the regeneration gas cooling unit condenses the steam contained in the regeneration gas by exchanging heat with the moisture separated from the regeneration gas.

Description

Gas treatment system and offshore plant having the same}

The present invention relates to a gas treatment system and an offshore structure comprising the same.

As environmental regulations have recently been strengthened, the use of natural gas close to eco-friendly fuel among various fuels is increasing. Natural gas can be extracted in gaseous form from wells located in inland or ocean strata, and the extracted natural gas undergoes pretreatment such as mercury removal, drying, NGL removal, etc., and then liquefaction process for storage and transportation. Can be liquefied.

Natural gas can be changed to a liquid state by cooling below a boiling point (eg, -162°C under 1 atmosphere) while exchanging heat with a refrigerant, and when it becomes a liquid state, the volume is reduced to 1/600 compared to the gas state. Transport efficiency can be increased.

The liquefaction process as described above can be carried out in an on-shore plant or an offshore FLNG, and liquefied natural gas can be stored in an LNG storage tank and then supplied to a consumer.

For example, natural gas may be supplied from an LNG storage tank to an on-shore city gas facility or a power generation facility, or may be delivered to a cargo tank of an LNG carrier and transported to a desired region by the LNG carrier.

At this time, the natural gas may be vaporized and consumed after being discharged from the LNG storage tank or the cargo tank, and the vaporization facility may be provided in an onshore plant or FLNG, or in a facility that consumes natural gas.

As described above, natural gas is consumed through a pre-treatment, liquefaction process, storage, transportation, and vaporization process after being extracted from the gas well, and various research and development are conducted to ensure stability and improve efficiency of gas production, processing, and supply. This is happening continuously.

The present invention was created to solve the problems of the prior art as described above, and the object of the present invention is to recover heat from the regenerated gas used during regeneration in the process of producing natural gas at sea or to separate it from liquefied natural gas. It is intended to provide a gas treatment system and a marine structure including the same, by cooling renewable gas with a portion of the evaporated gas or liquefied natural gas, which significantly improves energy efficiency.

A gas treatment system according to an aspect of the present invention is provided on a marine structure, and is a system for receiving and processing gas from a gas well, comprising: a water removal part having an adsorption column that adsorbs moisture contained in the gas produced in the gas well; And a liquefaction unit for liquefying the gas from which moisture has been removed, wherein the moisture removal unit comprises: a regeneration gas supply unit that supplies high-temperature regeneration gas to vaporize and separate moisture adsorbed on the adsorption column to the adsorption column; A regeneration gas cooling unit for condensing steam by cooling regeneration gas discharged from the adsorption column together with steam; And a water separation unit for separating the condensed moisture from the regeneration gas, and the regeneration gas cooling unit condenses the steam contained in the regeneration gas by exchanging heat with the moisture separated from the regeneration gas.

Specifically, the regenerated gas cooling unit condenses the steam contained in the regenerated gas by exchanging the moisture separated from the regenerated gas and the moisture flowing in from the outside with the regenerated gas, and can change the heat exchanged with the regenerated gas into steam. .

Specifically, the regeneration gas supply unit may have a steam heater that generates high temperature regeneration gas by exchanging heat generated by the regeneration gas cooling unit with low temperature regeneration gas.

Specifically, the regeneration gas supply unit has a regeneration gas heater that heats the regeneration gas by consuming fuel, and the steam heater may be provided upstream of the regeneration gas heater.

The offshore structure according to one aspect of the present invention is characterized by having the gas treatment system.

The gas treatment system and the marine structure including the same according to the present invention can innovatively improve energy use efficiency by efficiently cooling regeneration gas for regeneration of the adsorption unit in a process of adsorbing moisture from natural gas.

1 and 2 are partial conceptual views of a gas processing system according to a first embodiment of the present invention.
3 is a partial conceptual diagram of a gas processing system according to a second embodiment of the present invention.
4 and 5 are partial conceptual diagrams of a gas processing system according to a third embodiment of the present invention.
6 and 7 are partial conceptual diagrams of a gas processing system according to a fourth embodiment of the present invention.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments, which are associated with the accompanying drawings. In addition, it should be noted that, in addition to reference numerals to the components of each drawing in the present specification, the same components have the same numbers as possible, even if they are displayed on different drawings. In addition, in the description of the present invention, when it is determined that detailed descriptions of related known technologies may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, gas is a hydrocarbon such as LPG, LNG, ethane, and may mean a substance having a boiling point lower than room temperature, but for convenience, the present invention will be described as limited to the final production and storage of LNG (methane). In addition, in this specification, the gas is not limited to a gas phase in spite of the terminology.

Hereinafter, it is noted that high pressure (HP), low pressure (LP), high temperature, and low temperature are relative, and do not represent absolute values.

The present invention may include a gas treatment system described below and a marine structure on which the gas treatment system is mounted. First, the marine structure of the present invention will be briefly described.

Offshore structures are moored/fixed in the deep sea or offshore, and receiving, and processing, refining, and liquefying the gas produced from the gas well, and supplying it to the demander. It can mean offshore plants such as FLNG, FSRU, and fixed platforms. . Of course, the offshore structure of the present invention can be used as a concept encompassing a general merchant ship if the gas treatment configuration can be mounted.

Offshore structures include a hull side, which is a ship, and a top side, which is provided on the hull. A storage unit may be mainly provided on the hull side of the offshore structure, and for example, a liquefied gas storage tank or the like is provided. The liquefied gas storage tank is configured to purify and liquefy the production gas, and may be provided as a membrane type in order to stably store the gas in a cryogenic liquid state, but is not limited thereto.

A plurality of liquefied gas storage tanks may be provided in the longitudinal direction of the hull, and two or more may be provided in the left and right directions of the hull. The number or arrangement of liquefied gas storage tanks can be variously determined according to the size of the production gas to be processed by offshore structures.

The top side includes a configuration for treating gas. The top side may include a gas treatment system to be described later, and detailed configuration of the gas treatment system will be described below.

In addition to the top side, the upper side of the hull side may be provided with a residence cabin, an engine casing for discharging engine exhaust, and a flare tower, but most of the upper side of the hull side may be utilized for installation of the top side.

Hereinafter, the gas treatment system of the present invention will be described in detail with reference to FIGS. 1 to 7.

1 and 2 are partial conceptual views of a gas processing system according to a first embodiment of the present invention.

1 and 2, the gas treatment system 1 according to the first embodiment of the present invention is a system provided in an offshore structure to receive and process gas from a gas well W, and a water removal unit 10 , The liquefaction unit 20 is included. Of course, although not shown in the drawings, other facilities (mercury removal unit, low-temperature distillation unit, etc.) for treating the gas produced in the gas well W may be added.

The moisture removal unit 10 removes moisture contained in the gas produced in the gas well W. The moisture removal unit 10 may use the inlet filter 11 and the adsorption column 12 to remove moisture from the gas.

The gas supply line L10 may be connected to the water removal unit 10 from the gas well W. On the gas supply line L10, the inlet filter 11 and the adsorption column 12 may be arranged in series. The inlet filter 11 primarily removes moisture from the gas, and the moisture removed from the inlet filter 11 is discharged to the outside through the moisture discharge line L12.

The adsorption column 12 removes moisture from the gas that has passed through the inlet filter 11 secondaryly, and can separate moisture using adsorption. At this time, the adsorption column 12 uses a known adsorbent, and may be provided in one or more. For example, three adsorption columns 12 may be provided, and the gas supply line L10 is branched and connected to a plurality of adsorption columns 12, respectively. Equipped with a plurality of adsorption column 12 is to enable the removal of moisture to the other adsorption column 12 when the adsorption column 12 is regenerated.

Since the adsorption column 12 has limited adsorption of water through the adsorbent, it is difficult to adsorb more moisture when sufficient moisture is adsorbed to the adsorbent. Therefore, it is necessary to regenerate by removing moisture from the adsorbent and returning the adsorption column 12 to a state in which moisture can be removed again.

To this end, the present embodiment can supply hot regeneration gas to the adsorption column 12, so that the water adsorbed by the adsorbent is heated by heat and evaporates to separate from the adsorbent, and the evaporated steam is adsorbed together with the regeneration gas (12).

For regeneration of the adsorption column 12, the moisture removal unit 10 includes a regeneration gas supply unit 13, a regeneration gas cooling unit 14, and a water separation unit 15.

The regeneration gas supply unit 13 may supply high-temperature regeneration gas to vaporize and separate moisture adsorbed on the adsorption column 12 to the adsorption column 12. At this time, the regenerated gas is a sufficiently dried gas, and it is also possible to utilize the gas produced in the gas well W and then passed through the moisture removal part 10.

The regeneration gas may be heated to a temperature of 250°C to 280°C and supplied to the adsorption column 12. To this end, the regeneration gas supply unit 13 includes a regeneration gas heater 131 for heating the regeneration gas. .

The regenerative gas heater 131 is used to heat the regenerative gas by consuming fuel, wherein the fuel may be a part of the gas produced in the gas well W or may be separately provided fuel.

The regeneration gas heater 131 utilizes heat generated by combustion of fuel to heat the regeneration gas to 250 degrees C or more, so that when the regeneration gas is supplied to the adsorption column 12, the moisture attached to the adsorbent is changed to steam. can do.

The gas delivered from the gas well W is branched after passing through the inlet filter 11 along the gas supply line L10 and is delivered to each of the adsorption columns 12, and the regenerated gas is opposite to the gas supply line L10. Regeneration gas may be supplied to each adsorption column 12 through the provided regeneration gas supply line L11. However, since the adsorption column 12 is not adsorbed and regenerated at the same time, at least a portion of the gas supply line L10 may be used as the regeneration gas supply line L11.

The gas supply line (L10) is branched downstream from the inlet filter (11) and then re-joined after passing through each adsorption column (12) and transferred to the liquefaction section (20), and the regenerated gas supply line (L11) is also provided. . That is, the regeneration gas supply line (L11) is branched from the downstream of the regeneration gas heater (131), passes through each adsorption column (12) through the gas supply line (L10), and then rejoins the regeneration gas cooling unit (14). It is transferred to the water removal unit 10 through.

The regeneration gas cooling unit 14 cools the regeneration gas discharged from the adsorption column 12 together with steam to condense the steam to generate moisture. When the high temperature regeneration gas changes the moisture adsorbed on the adsorption column 12 to steam and then exits the adsorption column 12 together with the steam, the regeneration of the adsorption column 12 is completed, and the regeneration gas is full of steam. Becomes.

At this time, the regeneration gas cooling unit 14 may separate the steam contained in the regeneration gas to dry the regeneration gas, and separating the steam from the regeneration gas is achieved through cooling of the regeneration gas.

For cooling the regeneration gas, the regeneration gas cooling unit 14 may include an air cooling cooler 141. That is, the regeneration gas is discharged from the adsorption column 12 along the regeneration gas supply line (L11) and then cooled to 100 degrees C or less in the air-cooled cooler 141, so that steam contained in the regeneration gas can be condensed into moisture.

As the air-cooled cooler 141 is used, cooling of the regenerated gas is affected by the outside air temperature. In this case, the air-cooled cooler 141 may have a different load in consideration of the outside temperature and the flow rate of the regenerated gas, or the flow rate of the regenerated gas flowing into the air-cooled cooler 141 may be controlled by a valve or the like.

The moisture separation unit 15 separates the moisture condensed by the regeneration gas cooling unit 14 from the regeneration gas. Since the regeneration gas (gas phase) and water (liquid phase) have different phases, the water separator 15 may use a water separator 151 that implements gas-liquid separation.

The gaseous regeneration gas separated from the water separator 151 is discharged along the regeneration gas supply line L11, and the discharged regeneration gas may be introduced into the regeneration gas heater 131 and recycled.

Alternatively, since the regenerated gas utilizes the gas produced in the gas well W, and thus has a calorific value, it can also be consumed at a customer D such as a generator or a boiler. That is, the recycled gas from which moisture is separated after being used for regeneration of the adsorption column 12 may be recycled or consumed.

The liquefaction unit 20 liquefies the gas from which moisture has been removed. The liquefaction unit 20 may liquefy gaseous gas into a liquid phase using various non-limiting refrigerants such as nitrogen, propane, and mixed refrigerant. Hereinafter, the liquefaction unit 20 will be described on the assumption that a phase-changing material is used as a refrigerant while exchanging heat with gas.

The liquefaction unit 20 includes a liquefier 21 for exchanging gas and refrigerant, and the liquefier 21 can liquefy the gas from which moisture has been removed by exchanging heat with the refrigerant. When moisture is included in the gas, when the gas is liquefied, the liquefier 21 may be damaged due to condensation of moisture, and the moisture removal unit 10 is provided upstream of the liquefaction unit 20.

In order to supply the refrigerant to the liquefier 21, a refrigerant circulation line L21 is provided. That is, the liquefier 21 has a two-stream structure in which the gas supply line (L10) and the refrigerant circulation line (L21) through which the moisture-removed gas flows flow.

The refrigerant circulation line L21 includes a refrigerant compressor 211 for compressing a refrigerant, a refrigerant cooler 212 for cooling the compressed refrigerant, and a refrigerant separator 213 for gas-liquid cooling refrigerant, and the refrigerant separator 213 ) Is separated from the liquid refrigerant is transferred to the liquefier (21).

The liquid refrigerant may be vaporized as the gas is liquefied in the liquefier 21, and the gaseous refrigerant discharged from the liquefier 21 is mixed with the gaseous refrigerant separated from the refrigerant separator 213 and is a refrigerant compressor. (211).

In addition, a refrigerant expander (not shown) may be provided in the refrigerant circulation line L21 to lower the pressure of the compressed refrigerant to decrease the temperature of the refrigerant, and the refrigerant expander may be a pressure reducing valve or the like.

The gas liquefied by heat exchange with the refrigerant in the liquefier 21 flows into the gas-liquid separator 22. Since components having a very low boiling point, such as nitrogen, are mixed in the gas, components that remain in the gas phase may exist even if the main component such as methane is liquefied due to heat exchange by a refrigerant.

Therefore, the gas-liquid separator 22 can separate the gas remaining in the gas phase as an evaporation gas (flash gas), and transfer the liquid liquefied gas to a storage unit S such as a liquefied gas storage tank.

However, since the boil-off gas is also derived from the gas produced in the gas well W, and thus has a calorific value, the boil-off gas separated from the gas-liquid separator 22 can be consumed at a demand source D of a generator, an engine, etc. From the separator 22, a boil-off gas supply line L22 may be provided to the demand destination D.

As described above, in the present embodiment, the moisture contained in the gas produced in the gas well W is adsorbed and removed and then liquefied, and the adsorption performance can be continuously maintained by using regenerated gas.

3 is a partial conceptual diagram of a gas processing system according to a second embodiment of the present invention.

Hereinafter, the present embodiment will be mainly described in terms of differences from the previous embodiment, and parts omitted from description will be replaced with the previous content. It is noted that this is the same in other embodiments described later.

Referring to FIG. 3, in the gas treatment system 1 according to the second embodiment of the present invention, the regeneration gas cooling unit 14 replaces the water cooling cooler 142 in place of the air cooling cooler 141 in the previous embodiment. Includes.

In the case of the previous embodiment, the regenerated gas cooling unit 14 implements cooling by using external air for the regenerated gas containing moisture. However, in this case, the efficiency of separation of moisture from the regenerated gas may vary depending on the temperature of the outside air.

In addition, there is a high demand for steam in offshore structures, and heating is required to convert the moisture condensed in the renewable gas to steam. Therefore, in the present embodiment, considering the use of such energy, the water-cooled cooler 142 is placed to heat the moisture separated from the regenerated gas with the regenerated gas to condense the steam contained in the regenerated gas, and the moisture exchanged with the regenerated gas is steam. Can be supplied to the steam demand (D).

However, only the water separated from the regenerated gas cannot sufficiently dry the regenerated gas containing steam while passing through the adsorption column 12, so the water cooling cooler 142 of the present embodiment is separated from the regenerated gas and introduced from the outside. Heat exchanged with the regenerated gas to condense the steam contained in the regenerated gas.

At this time, the water inlet line L13 is connected to the water cooling cooler 142 from the outside, and the water outlet line L12 may be joined from the water separator 151 to the water inlet line L13. In addition, the outside is a separate water supply unit 142a, which may be configured to receive condensate discharged from a steam consumer or a fresh water tank, and the amount of water supplied from the outside is the flow rate of the regenerated gas, the state of the gas well (W), and the gas well ( It can be adjusted using a valve according to the moisture content of the gas supplied from W).

Steam generated in the water cooling cooler 142 may be supplied to a steam consumer such as a boiler through the steam supply line (L14), the regeneration gas supply unit 13 can also utilize the heat of the steam. To this end, the regeneration gas supply unit 13 includes a steam heater 132 for heating regeneration gas to steam, and a steam supply line L14 is connected from the water cooling cooler 142 to the steam heater 132.

The steam heater 132 may heat the steam generated in the regeneration gas cooling unit 14 with low temperature regeneration gas to generate high temperature regeneration gas. However, since the temperature of the regeneration gas required for the adsorption column 12 is 250 degrees C or more, the regeneration gas heater 131 described above may be provided downstream of the steam heater 132.

Therefore, the regenerated gas is heated in the steam heater 132 and cooled in the water-cooled cooler 142, the water-cooled cooler 142 uses the heat of the high-temperature regenerated gas to make moisture into steam, and the steam heater 132 is a water-cooled cooler ( The regenerated gas can be made to a high temperature using the steam generated in 142).

At this time, the steam supplied to the steam heater 132 may be condensed while exchanging heat with renewable gas, and the condensed moisture may be returned to the water cooling cooler 142 and circulated.

As described above, the present embodiment utilizes moisture separated from the regenerated gas when cooling for separation of the regenerated gas, and utilizes steam generated during cooling of the regenerated gas when heating the regenerated gas, so that it is not affected by the outside temperature. It is possible to remove moisture without being stable, and to maximize energy efficiency.

4 and 5 are partial conceptual diagrams of a gas processing system according to a third embodiment of the present invention.

4 and 5, in the gas treatment system 1 according to the third embodiment of the present invention, the regeneration gas cooling unit 14 uses an air-cooled cooler 141, and a gas heat exchanger 143 It may further include.

The regeneration gas cooling unit 14 may exchange heat with at least a portion of the evaporation gas that is gas-liquid separated from the liquefaction unit 20. In the gas-liquid separator 22 of the liquefaction section 20, the liquefied gas and the evaporation gas are separated, and the liquefied gas may be supplied to the storage section S, and the evaporation gas may be supplied to the demand destination D, which is required by the demand destination D. The temperature of the gas may be higher than the temperature of the evaporated gas separated from the gas-liquid separator 22 and close to the boiling point of the gas.

Therefore, the boil-off gas separated from the gas-liquid separator 22 must be supplied to the demand destination (D) after heating, and this embodiment can utilize the boil-off gas to cool the renewable gas in consideration of this energy flow.

The regeneration gas cooling unit 14 is provided with an air-cooled cooler 141 for condensing steam by cooling the regeneration gas, and a gas heat exchanger 143 provided downstream of the air-cooled cooler 141 to exchange evaporation gas and regeneration gas. Can have

In addition, an evaporation gas branch line (L22a) connected to the gas heat exchanger 143 is branched to the evaporation gas supply line (L22) connected from the gas-liquid separator 22 to the customer (D), and the evaporation gas supply line (L22) and The evaporation gas branch line (L22a) is provided with an evaporation gas supply valve (V22) and an evaporation gas branch valve (V22a), respectively, so that the flow rate of the evaporation gas supplied to the gas heat exchanger (143) or the customer (D) can be adjusted. .

The evaporation gas supply line L22 may be supplied from the gas-liquid separator 22 to the demander D via the liquefier 21, through which the low-temperature evaporation gas is removed from moisture and flows into the liquefier 21. It can be used to cool the gas, and it is possible to heat the boil-off gas supplied to the customer (D) without going through the gas heat exchanger (143).

On the other hand, the evaporation gas branch line (L22a) is connected from the gas-liquid separator 22 to the gas heat exchanger 143, so that the low-temperature evaporation gas is heated as it exchanges heat with the high-temperature regeneration gas. Thereafter, the heated boil-off gas may be joined to the boil-off gas supply line (L22) to transfer the boil-off gas to the customer (D).

Of course, the demand source (D) to which the boil-off gas supply line (L22) and the boil-off gas branch line (L22a) are connected may be different, and in this case, the boil-off gas supply line (L22) and the boil-off gas branch line (L22a) are not joined It may be connected to each demand destination (D).

Through this configuration, the liquefaction unit 20 supplies boil-off gas separated by gas to the customer (D), but at least some of the boil-off gas can be delivered to the gas heat exchanger 143, but the boil-off gas supply line (L22) As it passes through the liquefier 21, the liquefaction unit 20 heats the gas-separated evaporation gas from the liquefier 21 and supplies it to the customer (D), but at least a part of the evaporation gas is a gas heat exchanger ( 143) to be heated in the gas heat exchanger (143).

That is, some of the evaporated gas separated from the gas-liquid separator 22 is heated in the liquefier 21 and then supplied to the demand destination D, and the rest is heated in the gas heat exchanger 143 and then supplied to the demand destination D, and the gas The temperature of the evaporated gas heated in the heat exchanger 143 may be higher than the required temperature of the demand destination (D), but may be adapted to the required temperature of the demand destination (D) while being mixed with the evaporated gas heated in the liquefier 21. . Of course, a heating/cooling means for setting the temperature of the boil-off gas to the required temperature of the customer D may be added downstream of the confluence point of the boil-off gas supply line L22 and the boil-off gas branch line L22a.

In this embodiment, the boil-off gas is branched to the gas heat exchanger 143 and used to cool the regenerated gas is to consider the outside temperature. When the outside temperature is high, since the cooling of the regenerated gas cannot be sufficiently achieved by the air-cooled cooler 141, the present embodiment places the gas heat exchanger 143 into the air-cooled cooler 141 after the regenerated gas is pre-cooled with evaporative gas. By being sufficiently cooled, water separation from the regenerated gas can be smoothed.

To this end, the flow rate of the evaporated gas flowing into the gas heat exchanger 143 may vary depending on the outside temperature, and specifically, the opening degree of the evaporated gas branch valve V22a is adjusted according to the outside temperature flowing into the air-cooled cooler 141, The flow rate of the evaporated gas delivered to the gas heat exchanger 143 can be adjusted. At this time, the opening degree of the evaporation gas branch valve V22a or the like can be made by a ratio controller (not shown).

For example, when the outside air temperature is higher than the reference value, the evaporation gas branch valve V22a expands the opening degree, and the regeneration gas is sufficiently pre-cooled with the evaporation gas and then cooled in the air-cooled cooler 141 so that the steam in the regeneration gas condenses. On the other hand, when the outside temperature is lower than the reference value, the evaporation gas branch valve V22a closes the opening degree, so that the regeneration gas is cooled only in the air-cooled cooler 141 without heat exchange with the evaporation gas, so that moisture is separated.

The opening degree of the boil-off gas branch valve V22a can be adjusted by the external air temperature measured directly, or it can be made by the position of the offshore structure indirectly indicating the outdoor air temperature.

As described above, in the present embodiment, the regenerated gas containing steam is cooled with the air-cooled cooler 141 to condense the steam into moisture, but by precooling the regenerated gas with evaporation gas generated during liquefaction in case the outside temperature is high, moisture Separation efficiency can be ensured.

6 and 7 are partial conceptual diagrams of a gas processing system according to a fourth embodiment of the present invention.

6 and 7, in the gas treatment system 1 according to the fourth embodiment of the present invention, unlike the previous embodiment, the gas heat exchanger 143 of the regeneration gas cooling unit 14 replaces the evaporated gas. The liquefied gas can be used to pre-cool the regenerated gas.

The regeneration gas cooling unit 14 may exchange regeneration gas by exchanging at least a portion of the liquefied gas gas-liquid separated from the liquefaction unit 20 to cool the regeneration gas, and the gas heat exchanger 143 is a liquefied gas other than evaporation gas. It is possible to pre-cool the regeneration gas by exchanging heat with the regeneration gas.

To this end, the liquefaction unit 20 is separated from the gas supply line (L10) that transfers the liquefied gas separated from the gas-liquid separator 22 to the storage unit (S), and at least a part of the liquefied gas is transferred to the gas heat exchanger (143). A liquefied gas branching line (L10a) for transferring may be provided, and a liquefied gas branching valve (V10a) for adjusting the flow rate of liquefied gas delivered to the gas heat exchanger (143) is provided in the liquefied gas branching line (L10a).

The liquefied gas branch line L10a may transfer liquefied gas to the gas heat exchanger 143 to cool the regenerated gas, and the liquefied gas heat-exchanged in the regenerated gas may be vaporized and supplied to the customer (D).

That is, the liquefied gas branch line (L10a) is branched from the gas supply line (L10) to supply the liquefied gas via the gas heat exchanger (143) to the demand destination (D), and is supplied through the gas heat exchanger (143). It is connected to D), and may be joined to the evaporation gas supply line L22 upstream of the demand destination D.

However, the boil-off gas supply line (L22) may be connected to the demand destination (D) from the gas-liquid separator 22 through the liquefier 21, the liquefied gas branch line (L10a) as shown in the drawing, the boil-off gas supply line (L22) ) Is joined upstream of the liquefier 21, and the liquefied gas heat-exchanged with the regeneration gas may be additionally heated in the liquefier 21 and then supplied to the demand destination D.

The demand destination (D) operates by consuming the evaporated gas separated from the gas-liquid separator 22 as described above. However, the load of the demand source D or the flow rate of the evaporation gas may not be constant, and a case where the flow rate of the evaporation gas is insufficient compared to the gas demand amount of the demand source D may occur.

In order to prepare for this, the present embodiment, by supplementing some of the liquefied gas separated from the gas-liquid separator 22 to the demand destination (D), it is possible to ensure normal operation of the demand destination (D) even if the evaporation gas flow rate is insufficient. However, since the liquefied gas separated from the gas-liquid separator 22 is a low-temperature liquid, this embodiment transfers the low-temperature liquid liquefied gas to the gas heat exchanger 143 so as to be vaporized by the regenerated gas and then delivered to the customer (D).

At this time, the flow rate of the liquefied gas to be supplied to the demand destination (D) through the gas heat exchanger (143) may vary depending on the gas demand of the demand destination (D) and the amount of evaporated gas separated from the gas-liquid separator (22). Specifically, the liquefied gas branch valve (V10a) provided in the liquefied gas branch line (L10a), the opening degree can be adjusted in comparison to the required amount of the demand (D) and the amount of evaporated gas separated from the gas-liquid separator 22.

For example, if the amount of evaporated gas separated by gas-liquid compared to the demand of the demand (D) is insufficient, the liquefied gas branch valve (V10a) opens to open so that the liquefied gas is vaporized by the regenerated gas and then supplied with the evaporated gas to the demand (D) can do. On the other hand, when the demand amount of the customer D is equal to or less than the amount of evaporated gas that is gas-liquid separated, the liquefied gas branch valve V10a may close the opening to allow all of the gas-liquid separated liquefied gas to be transferred to the storage unit S.

As described above, in the present embodiment, when the flow rate of the evaporated gas generated during liquefaction does not meet the demand of the demand destination (D), some of the liquefied liquefied gas is supplemented with the demand destination (D), but cooling of the regenerated gas containing steam By utilizing the for the heating of the liquefied gas supplemented to the demand source (D), it is possible to increase energy use efficiency and realize power and cost savings.

The present invention is not limited to the above-described embodiments, and it is needless to say that a combination of the above embodiments or a combination of at least one of the above embodiments and a known technology may be included as another embodiment. For example, the present invention may include an embodiment having a regeneration gas cooling unit 14 including a water cooling cooler 142 and a gas heat exchanger 143.

In the above, the present invention has been described based on the embodiments of the present invention, but this is merely an example and does not limit the present invention, and those skilled in the art to which the present invention pertains will not depart from the essential technical content of the present embodiment. It will be appreciated that various combinations or variations and applications not illustrated in the examples are possible in the scope. Therefore, technical contents related to modifications and applications that can be easily derived from the embodiments of the present invention should be interpreted as being included in the present invention.

1: gas treatment system W: gas well
S: storage D: demand
10: moisture removal unit 11: inlet filter
12: adsorption column 13: regeneration gas supply
131: regenerative gas heater 132: steam heater
14: regeneration gas cooling unit 141: air cooling cooler
142: water cooling cooler 142a: water supply
143: gas heat exchanger 15: water separator
151: water separator L10: gas supply line
L10a: Liquefied gas branch line V10a: Liquefied gas branch valve
L11: Regeneration gas supply line L12: Water discharge line
L13: Moisture inlet line L14: Steam supply line
20: liquefaction section 21: liquefier
211: refrigerant compressor 212: refrigerant cooler
213: refrigerant separator L21: refrigerant circulation line
22: gas-liquid separator L22: evaporation gas supply line
V22: Boil-off gas supply valve L22a: Boil-off gas branch line
V22a: Evaporative gas branch valve

Claims (5)

A system that is provided on an offshore structure and receives and processes gas from a gas well,
A moisture removal unit having an adsorption column that adsorbs moisture contained in the gas produced in the gas well; And
It includes a liquefaction section for liquefying the gas from which the moisture is removed,
The moisture removal unit,
A regeneration gas supply unit supplying high-temperature regeneration gas to vaporize and separate moisture adsorbed on the adsorption column to the adsorption column;
A regeneration gas cooling unit for condensing steam by cooling regeneration gas discharged from the adsorption column together with steam; And
It includes a water separator for separating the condensed water from the regeneration gas,
The regeneration gas cooling unit exchanges moisture separated from the regeneration gas and the regeneration gas to condense the steam contained in the regeneration gas while changing the heat exchanged with the regeneration gas to steam.
The regeneration gas supply unit,
And a steam heater that heats the steam generated in the regenerated gas cooling unit with a low-temperature regenerated gas to generate a high-temperature regenerated gas. According to claim 1, wherein the regeneration gas cooling unit,
A gas treatment system characterized by condensing the steam contained in the regenerated gas by heat-exchanging the moisture separated from the regenerated gas and the moisture introduced from the outside with the regenerated gas, and changing the heat exchanged with the regenerated gas to steam. delete According to claim 1, The regeneration gas supply unit,
Has a regenerative gas heater that heats the regenerative gas by consuming fuel,
The steam heater is a gas treatment system, characterized in that provided on the upstream of the regeneration gas heater. A marine structure characterized by having the gas treatment system of claim 1, 2 or 4.

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