KR20160035187A - method of cold energy utilization - Google Patents

Abstract

According to an embodiment of the present invention, a cold heat utilizing method using a cold heat system exchanges heat with fuel supplied to a source of demand from a liquefied gas storage tank, and includes a PCM cold heat storage tank for storing a phase change material whose phase is changed to store cold heat of the fuel, and a cold heat supply line connected to a cold heat receiving device from the PCM cold heat storage tank so as to supply cold heat, and the method comprises: a step of measuring an amount of cold heat stored in the PCM cold heat storage tank; a step of measuring a required amount of the cold heat per apparatus; a step of calculating an amount of the cold heat which should be transferred from the PCM cold heat storage tank to each of the apparatuses; and a step of transferring the cold heat in the PCM cold heat storage tank to each of the apparatuses. According to the cold heat utilizing method in accordance with the present invention, when cryogenic liquefied gas is heated to be used as fuel, cold heat discharged from the liquefied gas is stored in a phase change material and used for cold thermal energy of an air conditioning unit or cooling a heating element, immediately or at intervals. Accordingly, energy can be saved because the cold heat is utilized rather than discarded. In addition, output of cold heat required from the air conditioning unit and the heating device can be reduced, thereby minimizing energy required for driving a vessel or an offshore plant.

Description

Methods of cold energy utilization

The present invention relates to a method of utilizing cold heat.

A ship is a means of transporting large quantities of minerals, crude oil, natural gas, or several thousand containers. It is made of steel and buoyant to float on the water surface. The thrust generated by rotation of the propeller ≪ / RTI >

Such a vessel generates thrust by driving the engine. In this case, the engine uses gasoline or diesel to move the piston so that the crankshaft is rotated by the reciprocating movement of the piston, so that the shaft connected to the crankshaft is rotated to drive the propeller It was common.

In recent years, however, LNG fuel supply systems for driving an engine using LNG as a fuel have been used in an LNG carrier carrying Liquefied Natural Gas (LNG) It is also applied to other ships.

Generally, it is known that LNG is a clean fuel and its reserves are more abundant than petroleum, and its usage is rapidly increasing as mining and transfer technology develops. This LNG is generally stored in a liquid state at a temperature of -162 ° C. or below under 1 atm. The volume of liquefied methane is about one sixth of the volume of methane in a gaseous state, The specific gravity is 0.42, which is about one half of that of crude oil.

However, the temperature and pressure required to drive the engine may be different from the state of the LNG stored in the tank. Therefore, in recent years, research and development have been made on the technology of controlling the temperature and pressure of the LNG stored in the liquid state and supplying the engine to the engine.

However, LNG at -162 ° C radiates 840 kJ / kg of cold heat when it is vaporized by NG. To utilize such cold heat, LNG-FSRU generates cold heat only in the regeneration process. In case of LNG- In situations such as changes in engine load or propulsion using general fuel oil, the degree of cold generation varies and there is a restriction to use as constant energy.

SUMMARY OF THE INVENTION The present invention has been made to improve the prior art, and an object of the present invention is to provide a method of utilizing a cold heat that minimizes energy required for operation of a ship / offshore plant by converting cold energy, which is difficult to be discarded or constantly used, .

A method of utilizing cold heat according to an embodiment of the present invention includes a PCM shaft cooling / heating tank in which phase change material is stored for heat exchange with fuel supplied from a liquefied gas storage tank to a customer, And a cold / hot supply line connected to the PCM shaft cooling / heating tank to supply the cold / hot water, the method comprising: Measuring a cold storage amount of the PCM shaft cooling / heating tank; Measuring the amount of heat required for each device; Calculating an amount of cool heat to be delivered to the equipment in the PCM shaft cooling / heating tank; And transmitting cold heat of the PCM shaft cooling / heating tank for each of the equipment.

Specifically, in the step of transmitting the cold heat of the PCM shaft cooling tank, the cold heat of the PCM shaft cooling tank is transferred to the sea water, and cold heat is transferred from the cooled sea water to the equipment.

Specifically, the method further includes the step of measuring an inflow amount and a temperature of the seawater to receive the cold heat from the PCM shaft cooling / heating tank after the step of measuring the required heat amount for each equipment.

Measuring the temperature of the seawater for delivering cold heat to each of the equipment, after the step of transmitting the cold heat of the PCM shaft cooling / heating tank by the equipment; And discharging the seawater when the state of the seawater meets the discharge criterion.

Specifically, the step of transferring the cold heat of the PCM shaft cooling / heating tank to each of the equipment is characterized in that the cooling heat is directly transferred from the PCM shaft cooling / heating tank to the equipment.

In the method of utilizing cold heat according to the present invention, when heating is performed to use cryogenic liquefied gas as fuel, the cold heat discharged from the liquefied gas is stored in the phase change material and used immediately or as a cold energy of the air- By using it to cool down the equipment, it is possible to reduce the energy required to operate the ship or the offshore plant by reducing the amount of cold heat required by the air conditioner and the heating device, .

In addition, the present invention can be applied to a PCM cooling / heating system such as a PCM cooling / heating system in which a liquefied gas processed in a liquefied gas processing system is continuously supplied to a PCM shaft cooling / So that the cold heat of the liquefied gas can be prevented from being discarded and the amount of cold heat generated in the air conditioner or the like can be reduced, thereby minimizing the energy required for operation of the ship or offshore plant.

1 is a view showing a cooling / heating system according to a first embodiment of the present invention.
2 is a view illustrating a method of utilizing cold heat according to a second embodiment of the present invention.
3 is a flowchart of a method of utilizing cold heat according to a third embodiment of the present invention.
4 is a flowchart of a method of utilizing cold heat according to a fourth embodiment of the present invention.
5 is a flowchart of a method of utilizing cold heat according to a fifth embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The objects, particular advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements have the same numerical numbers as much as possible even if they are displayed on different drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a view showing a cooling system according to a first embodiment of the present invention, and FIG. 2 is a diagram illustrating a cooling system according to a second embodiment of the present invention.

As shown in FIG. 1, the cooling system 1 according to an embodiment of the present invention includes a PCM shaft cooling / heating tank 40 and a cooling / heating supply line 50.

The PCM shaft cooling / heating tank 40 stores a phase change material (PCM) cooled by heat exchange with the fuel supplied from the liquefied gas storage tank 10 to the customer 20.

The PCM shaft cooling and heating tank 40 is provided so that the fuel supply line 21 connected from the liquefied gas storage tank 10 to the consumer 20 is passed through the inside thereof so that the stored phase change material can be heat- .

Here, the liquefied gas storage tank 10 and the customer 20 are included in a liquefied gas processing system (not shown). The liquefied gas processing system not only processes liquefied gas but also generates power using liquefied gas .

That is, in the liquefied gas processing system, a boosting pump (not shown) pressurizes the liquefied gas discharged from the storage tank 10 through the fuel supply line 21 to several to several tens of bar, Pressurizes the liquefied gas to a pressure required by the customer 20, for example, the customer 20, and supplies the pressurized liquefied gas to the heat exchanger (see Fig. 2). The heat exchanger 30 can increase the temperature of the liquefied gas supplied from the pump and supply the liquefied gas in the supercritical state to the customer 20.

Here, the liquefied gas storage tank 10 is to store the fuel to be supplied to the customer 20, and the liquefied gas storage tank 10 must store the fuel in a liquid state, It can have tank form. For example, the liquefied gas storage tank 10 may include an outer tank (not shown), an inner tank (not shown), a thermal insulation (not shown), and may store the stored liquefied gas in a liquefied gas storage tank A manhole structure (not shown) may be provided at an upper portion of the liquefied gas storage tank 10 so that the liquefied gas can be discharged to the upper side of the liquefied gas storage tank 10.

The customer 20 is driven through the liquefied gas supplied from the liquefied gas storage tank 10 to generate thrust. At this time, the customer 20 may be a MEGI engine or a dual fuel engine. When the customer 20 is a dual fuel engine, liquefied gas or oil may be supplied selectively without supplying a mixture of liquefied gas and oil. This is to prevent the mixture of two materials having different combustion temperatures from being mixed to prevent the efficiency of the consumer 20 from being lowered.

In this liquefied gas processing system, the liquefied gas passing through the fuel supply line 21 can be heat-exchanged via the PCM shaft cooling / heating tank 40.

As described above, since the fuel supply line 21 passes through the PCM shaft cooling / heating tank 40, the phase change material inside the PCM shaft cooling / heating tank 40 is heat-exchanged with the liquefied gas, So that the phase change material has cold heat.

Here, the fuel supply line 21 in the PCM shaft cooling / heating tank 40 may have a spiral shape or a zigzag shape from one side (inlet) to the other (outlet) so as to expand the contact surface with the phase change material, The shape can be variously modified, such as a curved shape or a bent shape at a right angle.

This PCM shaft cooling / heating tank 40 can be located upstream of the heat exchanger (see FIG. 2 or the vaporizer) of the liquefied gas processing system on the fuel supply line 21 to reduce the load on the heat exchanger 30, The phase change material stored in the PCM shaft cooling / heating tank 40 may store cold heat transferred from the liquefied gas and used when necessary. That is, it is possible to minimize the energy required for operation of a ship or an offshore plant by converting the cold heat obtained from the liquefied gas into energy without discarding it by heating the liquefied gas.

Although not shown in the drawing, the PCM shaft cooling / heating tank 40 may be composed of multiple stages (or may be divided into a plurality of spaces), and the phase change material stored in the multi-stage PCM shaft cooling / Each of which may be different in phase change point from each other. Accordingly, the amount of cold stored in each of the multi-stage PCM shaft cooling / heating tanks 40 may be different.

For example, the phase change material may comprise a first material and a second material, wherein the first material has a first phase change point and the second material has a second phase change point that is higher than the first phase change point Lt; / RTI > The first material and the first material can be made of materials of known techniques.

The cooling / heating supply line 50 has a structure for discharging the cold heat of the phase change material obtained from the liquefied gas in the PCM shaft cooling / heating tank 40 to the cooling / heating device 60, To the device (60).

Here, the cold / hot supply line 50 may include a first line 51 and a second line 52 to efficiently utilize the first material and the second material having different phase change points. For example, the first line 51 may be a path for transferring the cold energy of the first material, and the second line 52 may be a path for transferring the cold energy of the second material.

When the phase change point of the second material is higher than the phase change point of the first material, the second material is phase-changed (e.g., solid in liquid) at a higher temperature than the first material to store the cold obtained from the phase change. And, since the first material is phase-changed at a lower temperature than the second material, it receives more cold heat and stores a phase change (for example, solid in liquid) to save the cold obtained from the phase change.

At this time, the cold heat of each of the first material and the second material may be individually moved along the first line 51 and the second line 52 and supplied to the cold heat receiving device 60. In this case, when the first material and the second material are separated and stored, the first line 51 is connected to the PCM shaft cooling / heating tank 40 And the second line 52 may pass through the region of the PCM shaft cooling / heating tank 40 where the second material is stored.

On the other hand, when the PCM shaft cooling / heating tank 40 is composed of multiple stages (plural tanks), the phase change material having the same phase change is stored in the individual spaces, and the first line 51 And the second line 52 may pass through the tank in which the second material is stored.

In this embodiment, since the second material has a phase change point higher than that of the first material, the cold heat of the first material can be supplied to the heat receiving device 60 that requires relatively high heat. Here, the cooling / heating device 60 may include an air conditioner 61 and a heating device 62.

The first line 51 is connected to an air conditioner 61 such as an HVAC and an air conditioner to supply cold and heat to the air conditioner 61. The second line 52 is connected to a heat generating device 62 such as an engine, (62).

Here, the cold / hot supply line 50 is a duct for forming a path for gas or liquid to flow, and the liquid on the cold / hot supply line 50 passing through the phase change material in the PCM shaft cooling / Cold heat can be obtained from the material.

1, the PCM shaft cooling / heating tank 40 is provided on the fuel supply line 21, and the fuel supply line 21 directly exchanges heat with the phase change material in the PCM shaft cooling / heating tank 40 , And the phase change material is transferred from the liquefied gas to the cold heat.

However, this is merely an example for facilitating understanding and explanation of the present invention, and the present invention is not limited to this, and various modifications thereof are various.

As another example, as shown in FIG. 2, the cooling system 2 according to the second embodiment of the present invention includes a PCM shaft cooling / heating tank 40A and a cooling / heating supply line 50.

The cooling system 2 of the second embodiment differs from the PCM cooling / heating tank 40A of the first embodiment in that the PCM shaft cooling / heating tank 40A is connected to the liquefied gas storage tank 10 connected to the customer 20 through the heat exchanger 30 on the fuel supply line 21A.

That is, the PCM shaft cooling / heating tank 40A of the present embodiment is connected to the heat exchanger 30 to receive cold heat, and the PCM shaft cooling / heating tank 40A is connected to the heat exchanger 30 through a heat transfer material (for example, The refrigerant circulation line 31 through which the heat transfer material flows can be provided.

Here, the heat transfer material is configured to transfer cold heat, which is different from that in which the phase change material stores cold heat. The heat transfer material receives the cold heat from the liquefied gas in the heat exchanger 30 and is supplied to the PCM shaft cooling / heating tank 40A along the refrigerant circulation line 31 to transfer cold heat to the phase change material in the PCM shaft cooling / The heat transfer material is transferred to the heat exchanger 30 along the refrigerant circulation line 31 and is re-cooled. As a result, the heat transfer material passes through the refrigerant circulation line 31 and cooling and heating are repeatedly performed have.

As described above, in the present embodiments, the cold heat discharged from the liquefied gas is stored in the phase change material, and used immediately or in a time lag as the cold energy of the air conditioner 61 or used for cooling the heat generator 62, The energy required for operation of the ship or the offshore plant can be minimized because the amount of cold heat required by the air conditioner 61 and the heat generator 62 can be reduced.

FIG. 3 is a flowchart of a method of utilizing cold heat according to a third embodiment of the present invention, and FIG. 4 is a flowchart of a method of utilizing cold heat according to the fourth embodiment of the present invention.

As shown in FIG. 3, the method for utilizing cold heat according to an embodiment of the present invention includes steps of measuring a cold storage amount of a PCM shaft cooling / heating tank (S10) (S30) of measuring the amount and temperature of the seawater to receive cold and heat from the PCM shaft cooling / heating tank (S30), calculating the amount of cold heat to be transmitted to the equipment in the PCM shaft cooling / heating tank (S50) of transmitting cold heat of the PCM shaft cooling / heating tank (S50), measuring the temperature of the seawater for delivering cold and cold by the equipment (S60), and discharging the seawater do.

Here, the present embodiment may be applied not only to the cooling system 1 or 2 according to the first or second embodiment, but also to a general cooling system. In the present embodiment, the cooling system 1 of the first embodiment will be described as an example for convenience of explanation and understanding, but the present invention is not limited thereto, and a duplicate description will be omitted.

First, in step S10, the cold storage amount of the PCM shaft cooling / heating tank 40 is measured.

A plurality of sensors (not shown) may be provided in the PCM shaft cooling / heating tank 40 in which the PCM (phase change material) is stored, and the sensor can sense the phase change of the PCM and the phase of the PCM.

The plurality of sensors are provided in the PCM shaft cooling / heating tank 40 so as to be spaced apart from each other. For example, the sensors may be provided in various forms such as up, down, left, right or radial. The plurality of sensors can detect the temperature and the phase change of the PCM irrespective of the position of the bottom, top, or corner of the inside of the PCM shaft cooling / heating tank 40.

The phase change of the PCM can be measured by the density difference or the ratio of the liquid to the solid state generated from the liquid to the solid, and is phase-changed into the solid, and the amount (volume) The total amount of cold storage of the PCM stored in the PCM shaft cooling / heating tank 40 is measured by measuring the temperature and the amount of the PCM in the liquid state in which the temperature is lowered due to the cold.

That is, the sum of the cold storage amount of the PCM having the lowered temperature can be the total of the cold storage amount of the PCM although the phase change with the stored amount of the cold heat of the PCM having the phase changed is not achieved.

In step S20, the required amount of heat for each equipment is measured. Here, the equipment may include an air conditioner (61) and a heating device (62) that require cold heat as the heat receiving device (60).

For example, the air conditioner 61 is composed of an HVAC and an air-conditioner, and the required temperature (for example, 20 ° C to 30 ° C) may be different depending on the area in which the HVAC and the air conditioner are driven, ) Can be made different from each other.

In other words, the required amount of cold heat to generate cold by each equipment can be varied depending on the influence of the external environment (solar heat, seasonal factors, etc.) or depending on environmental conditions (space size, etc.) do.

At this time, the required amount of cooling heat for each equipment is set by the user to set a certain value as a default value for the required cold heat according to the individual equipment, or for the environment change (season, etc.) measured by the surrounding environment and driving stabilization of the heat generating device 62 It can be measured corresponding to the temperature set according to the required temperature or the like.

In step S30, the storage amount and the temperature of the seawater are measured.

In this embodiment, the cold heat can be transmitted to each of the equipment by the seawater whose phase change material is heat-exchanged with the seawater and the cold heat is obtained from the phase change material.

At this time, a sea water tank (not shown) in which seawater is stored and a sea water line (not shown) circulating in the seawater tank may be provided by measuring the storage amount and temperature of the seawater obtained from the phase change material, The sea water line can receive cold heat from the PCM shaft cooling / heating tank 40 via the PCM shaft cooling / heating tank 40, and the sea water can obtain cold heat.

Here, the cold / hot supply line 50 may be connected to the seawater tank, and may be a path for transferring the cold water to the cold water. On the other hand, when the stored amount of seawater is measured, the seawater can flow in from the outside of the ship. It is needless to say that the inflow amount and the discharge amount of seawater can be measured separately.

In step S40, the amount of cold heat to be delivered for each equipment in the PCM shaft cooling / heating tank 40 is calculated.

The cold storage amount of the PCM shaft cooling / heating tank 40 measured in the step S10 described above may be different from the cooling / heating required amount of each equipment measured in the step S20. When the cold storage capacity of the PCM storage tank 40 is higher than the storage capacity of the PCM storage tank 40, it is possible to supply all of the cold storage in accordance with the required cooling capacity of the refrigerator 40. At this time, .

On the other hand, in the case where the cold storage capacity of the PCM storage / cooling tank 40 is less than the required storage capacity of each equipment, the cooling / heating efficiency of the PCM storage / 40 and the cold storage amount of the PCM shaft cooling / heating tank 40 may be distributed, and the distribution of the cold / hot storage amount of the PCM shaft cooling / heating tank 40 may be performed in steps S10 and S20 The value measured by the heat source becomes the input value, and the value of the cold heat amount can be calculated.

In step S50, the cold heat of the PCM shaft cooling / heating tank 40 is transferred for each equipment.

The value to which the cold heat is distributed is set according to the amount of the cold heat calculated in step S40 and the cold heat can be transmitted by controlling the opening degree of the cold / hot supply line 50 according to the calculated distribution amount, . Here, a damper is provided on the cold / hot supply line 50 so that the flow of the seawater via the cool / heat supply line 50 can be adjusted by controlling the opening degree of the damper.

In step S60, the temperature of the seawater is measured.

When the seawater whose temperature is different by the PCM and the cold / hot supply line (50) is arbitrarily discharged, there is a possibility of deteriorating the marine environment so that the seawater temperature inside the seawater tank is measured do.

Here, a separate sensor (not shown) is provided in the seawater tank to measure the temperature of the seawater in real time.

In step S70, the state of the seawater discharges seawater when the discharge criterion is satisfied.

When the seawater used for the heat exchange of cold and heat satisfies the discharge condition, the sea water is discharged. If the temperature is extremely lower than the sea water temperature, And discharged according to the discharge standard in a state where the temperature is raised.

3, when the cold heat is supplied from the PCM shaft cooling / heating tank 40 to the cold / hot supply line 50, the cool / heat transfer medium is transferred using seawater. However, the present invention is not limited to this, The cold / hot supply line 50 may directly receive cold heat from the PCM shaft cold / heat tank 40 without using the cold / heat transfer medium.

That is, as shown in FIG. 4, the method for utilizing cold heat according to the fourth embodiment includes a step (S10) of measuring a cold / hot storage amount of a PCM shaft cooling / heating tank, a step (S20) (S41) of measuring the amount of cold heat to be delivered to the equipment in the cooling / heating tank, and transmitting the cold / cold of the PCM shaft cooling / heating tank to each of the equipment (S51).

Unlike the third embodiment, unlike the third embodiment, the cold heat is directly transferred from the PCM shaft cooling / heating tank 40 to each equipment. Step S40 of the third embodiment is a step S41 of the third embodiment in which the PCM shaft cooling / Measuring the amount of cold to be delivered is the same or similar.

However, in the third embodiment, the storage amount and the temperature of the seawater are measured by using the seawater. In this embodiment, the storage amount and the temperature of the seawater in the step S30 of the third embodiment are measured, , The seawater discharge in step S70 may be omitted.

That is, step S41 is performed after step S41 in this embodiment, and step S51 is performed. In step S51, PCM cold heat is transmitted for each equipment, which is performed in the same manner as or similar to step S50.

As described above, in the present embodiments, the cold heat discharged from the liquefied gas is stored in the phase change material to be used as the cooling energy of the air conditioner 61 or to cool the heat generating device 62, It is possible to reduce the amount of cold heat required by the air conditioner 61 and the heat generating device 62 and to minimize the energy required for operation of the ship or offshore plant.

5 is a flowchart of a method of utilizing cold heat according to a fifth embodiment of the present invention.

As shown in FIG. 5, the method for utilizing cold heat according to the fifth embodiment includes a step S110 of measuring a cool / heat storage amount of a PCM shaft cooling / heating tank, a step S120 of measuring a supply amount and a temperature of a liquefied gas, A step S140 of measuring the cold temperature discharged from the cooling / heating tank S130, a step S140 of calculating the target temperature of the liquefied gas, a step S150 monitoring the cool heat transferred from the liquefied gas to the PCM shaft cooling / (S160).

Here, the present embodiment may be applied not only to the cooling system 1 or 2 according to the first or second embodiment, but also to a general cooling system. In the present embodiment, the cooling system 1 of the first embodiment will be described as an example for convenience of explanation and understanding, but the present invention is not limited thereto, and a duplicate description will be omitted.

In step S110, the cold storage amount of the PCM shaft cooling / heating tank 40 is measured. This can be performed in the same or similar manner as in the third and fourth embodiments. A plurality of sensors (not shown) may be provided in the PCM shaft cooling / heating tank 40 in which the PCM is stored, However, the sum of the amount of cold heat stored in the PCM with the reduced temperature can be the sum of the stored amount of the cold stored in the PCM.

In step S120, the supply amount and the temperature of the liquefied gas are measured.

This embodiment is carried out to control whether or not the PCM is cooled according to the heat exchangeability of the liquefied gas processed in the liquefied gas processing system and to discharge cold heat (supply cold heat by an air conditioner or the like). In step S120, By grasping the amount (supply) and temperature of the gas, it allows the PCM to extract the amount of cold that it can store.

Here, the supply amount of the liquefied gas may be the flow rate of the liquefied gas on the fuel supply line 21 supplied to the customer 20, and the supply amount and the temperature of the liquefied gas may be measured by a flow sensor provided on the fuel supply line 21, Or the like.

In step S130, cold heat discharged from the PCM shaft cooling / heating tank is measured.

When the liquefied gas processing system is driven so that the PCM obtains the cold heat and simultaneously the cold heat of the PCM is supplied to the heat receiving apparatus 60, the amount of the cold heat that the PCM can additionally store is the amount of the cold heat discharged to the heat receiving apparatus 60 Lt; / RTI >

Accordingly, the step S130 is for measuring the cold heat discharged from the PCM shaft cooling / heating tank 40, and the cooling / heating supply mechanism for discharging the PCM is performed by the cold / hot supply line 50, And the function and operation of the cold /

In step S140, the target temperature of the liquefied gas is calculated.

The liquefied gas is heated to a temperature required by the customer 20 in the course of supplying the liquefied gas to the customer 20, which is preheated by supplying cold heat to the PCM in the PCM shaft cooling tank 40, have.

The target temperature calculation for preheating and heating the liquefied gas can be made differently depending on whether the heating device (heat exchanger or the like) can be driven or not, and can be made corresponding to the required temperature of the liquefied gas required by the customer 20.

In step S150, the cold heat transferred from the liquefied gas to the PCM shaft cooling / heating tank 40 is monitored.

For example, a PCM that obtains heat from a liquefied gas by heat exchange with a liquefied gas may solidify the liquid to store cold, but the maximum storage capacity may be limited. At this time, preheating of the liquefied gas may be difficult if the cold storage state of the PCM is close to or equal to the maximum storage capacity.

Accordingly, in step S150, the cool heat transferred to the PCM is monitored in real time so that the liquefied gas can supply heat to the PCM to heat the liquefied gas during the operation of the liquefied gas processing system, and monitoring is performed in steps S110 to S140 In a loop.

In step S160, cold heat stored in the PCM shaft cooling / heating tank 40 is discharged.

For example, when the target temperature of the liquefied gas is larger than the amount by which the PCM is able to chill the cold heat, it is possible to discharge the cold heat so as to increase the chiller capacity of the PCM, or to improve the driving efficiency of the cold / The cold heat of the PCM obtained by heat exchange from the liquefied gas can be supplied to the air conditioner 61 and the heating device 62 or the like.

As described above, in the present embodiment, the liquefied gas processed in the liquefied gas processing system, such as measuring the cooling state of the PCM shaft cooling / heating tank 40 in real time, is always supplied with the cold heat to the PCM shaft cooling / heating tank 40, It is possible to control the cooling and discharging of the PCM so that the cold heat of the liquefied gas can be prevented from being discarded and the amount of cold heat to be generated in the air conditioner can be reduced to minimize the energy required for operation of the ship or offshore plant.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It is obvious that the modification and the modification are possible.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

1, 2: Cooling and heating system 10: Liquefied gas storage tank
20: customer demand 21, 21A: fuel supply line
30: Heat exchanger 40, 40A: PCM shaft cooling / heating tank
50: cold / hot supply line 51: first line
52: second line 60: cooling / heating device
61: air conditioner 62: heating device

Claims (5)

A PCM shaft cooling / heating tank in which a phase change material that is phase-exchanged with fuel supplied from a liquefied gas storage tank to a customer and stores a phase change material for storing cold heat of the fuel is stored; And a cold / hot supply line connected to the PCM shaft cooling / heating tank to supply the cold / hot water to the cold / hot water supply unit,
remind Measuring a cold storage amount of the PCM shaft cooling / heating tank;
Measuring the amount of heat required for each device;
Calculating an amount of cool heat to be delivered to the equipment in the PCM shaft cooling / heating tank; And
And transferring the cold heat of the PCM shaft cooling / heating tank to each of the devices. The method according to claim 1,
Wherein the step of delivering the cold heat of the PCM shaft cooling /
Wherein the cold heat of the PCM shaft cooling / heating tank is transferred to the seawater, and the cold heat is transferred from the cooled seawater to the equipment. 3. The method of claim 2,
After the step of measuring the heat demand by equipment,
Further comprising the step of measuring an inflow amount and a temperature of the seawater to receive cold heat from the PCM shaft cooling / heating tank. The method of claim 3,
After the step of transferring the cold heat of the PCM shaft cooling /
Measuring the temperature of the seawater for delivering cold heat to the equipment; And
And discharging the seawater when the state of the seawater satisfies the emission standard. The method according to claim 1,
Wherein the step of delivering the cold heat of the PCM shaft cooling /
Wherein the cold heat is directly transferred from the PCM shaft cooling / heating tank to the equipment.

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