JP5409440B2 - Refrigeration refrigerant manufacturing method using intermediate medium vaporizer and refrigeration refrigerant supply facility - Google Patents

Description

  The present invention relates to a method for producing a refrigeration refrigerant and an refrigeration refrigerant supply destination facility using an intermediate medium type vaporizer that vaporizes liquefied gas such as liquefied natural gas.

  As a means for continuously vaporizing liquefied gas such as liquefied natural gas (LNG) with a compact structure, an intermediate medium type vaporizer using a heat source medium and an intermediate medium is known. In this intermediate medium type vaporizer, the intermediate medium evaporated by the heat source medium is heat-exchanged with the liquefied gas to condense the intermediate medium, and the liquefied gas is vaporized by the condensation heat.

  In Patent Document 1, an intermediate heat medium type heat exchanger using seawater as a heat source medium, a parallel flow heat exchanger using seawater as a heat source medium, and a countercurrent heat exchanger are connected in series, and LNG is added in this order. A large-scale class of liquefied natural gas vaporizers that pass through and vaporize is disclosed.

  Further, Patent Document 2 discloses a medium-scale class intermediate medium type vaporizer in which hot water or the like is used as a heat source medium, and the heat source pipe is provided with two or more passes to increase the flow velocity in the pipe, and a natural gas supply method using the vaporizer. Is disclosed.

JP-A-53-5207 JP 2001-200995 A

By the way, in recent years, the industry has been given a major proposition of reducing CO ₂ by 25% due to low carbonization, and fuel conversion from oil to natural gas (NG) is progressing. Moreover, cold recovery from LNG has been studied for some time, and some have been put into practical use.

  Cold energy recovery from LNG has been put to practical use for cold power generation in large-scale class carburetors, and for refrigeration warehouse replacement or air conditioning in medium- and small-scale class carburetors. An intermediate medium type vaporizer is used as a large-scale class cold-heat recovery vaporizer. On the other hand, LNG / refrigerant direct heat exchangers are used as medium- and small-scale class cold-heat recovery vaporizers.

Like the food industry, in an industry that has both LNG demand and refrigeration refrigerant demand, LNG vaporization equipment that collects cold heat from LNG and cools the refrigeration refrigerant reduces running costs and reduces CO ₂ emissions. It is extremely effective. However, the direct heat exchanger, which is a medium-to-small class cold heat recovery vaporizer, has problems such as freezing of refrigerant, generation of thermal stress, and accompanying fatigue accumulation and weld cracking. For this reason, it has been impossible to sufficiently reduce the running cost and CO _{2 in} the medium-to-small-scale class cold-heat recovery vaporizer.

SUMMARY OF THE INVENTION An object of the present invention is to provide a refrigerant supply method and refrigerant supply using an intermediate medium type vaporizer capable of sufficiently reducing running costs and CO _{2 in} a medium-to-small-scale class cold-heat recovery vaporizer. To provide advanced equipment.

  The method for producing a refrigeration refrigerant using the intermediate medium vaporizer according to the present invention includes the shell containing an intermediate medium having a boiling point of −40 ° C. or lower under normal pressure, and the liquid intermediate medium so as to be immersed therein. A heat source pipe provided in the shell and having a freezing temperature of −20 ° C. or less supplied from outside passes through the inside, and a liquefied gas provided in the shell and supplied from outside passes through the inside. A refrigerant refrigerant manufacturing method using an intermediate medium type vaporizer comprising a heat pipe, wherein the liquid intermediate medium in the shell exchanges heat with the refrigerant refrigerant in the heat source pipe, And evaporating the liquid intermediate medium, cooling the refrigeration refrigerant to a predetermined temperature in the heat source pipe, and exchanging heat between the liquefied gas in the heat transfer pipe and the evaporated intermediate medium in the shell. The above With evaporating the liquefied gas within the tube, characterized by having a the steps of liquefying the intermediate medium evaporated in the shell.

According to the above configuration, the intermediate medium having a boiling point under normal pressure of −40 ° C. or less and a frozen refrigerant having a freezing temperature of −20 ° C. or less are subjected to heat exchange. The liquefied gas is evaporated in a low temperature region below zero. At this time, the intermediate medium that has recovered the cold heat of the liquefied gas is liquefied to cool the refrigeration refrigerant to a predetermined temperature, so that the refrigeration refrigerant can be used in a refrigerator, an air conditioner, or the like. And, by using such an intermediate medium type vaporizer as a vaporizer for cold / heat recovery of the medium / small class, the running cost and CO ₂ can be sufficiently reduced in the vaporizer for cold / heat recovery of the medium / small class. Can do.

  Moreover, in the manufacturing method of the refrigerating refrigerant | coolant using the intermediate-medium type vaporizer | carburetor in this invention, you may further have the process of heating the said liquefied gas evaporated from the said heat exchanger tube. According to said structure, the vaporization gas of desired temperature can be supplied to a supply destination by heating the evaporated liquefied gas (vaporization gas) discharged | emitted from the inside of a heat exchanger tube.

  Further, in the method for producing a refrigeration refrigerant using the intermediate medium type vaporizer according to the present invention, a liquefied gas vaporizer provided in parallel with the intermediate medium type vaporizer and supplied with a heat source and the liquefied gas from the outside is further provided. And the liquefied gas vaporizer may further include a step of vaporizing the liquefied gas with heat of the heat source. According to the above configuration, in parallel with the vaporization of the liquefied gas by the intermediate medium type vaporizer, the liquefied gas is vaporized by the liquefied gas vaporizer, and liquefied according to the increase or decrease in the amount of vaporized liquefied gas by the intermediate medium type vaporizer. The total vaporization amount of the liquefied gas can be adjusted by increasing / decreasing the vaporization amount of the liquefied gas by the gas vaporizer. Further, by using the liquefied gas vaporizer as a backup for the intermediate medium type vaporizer, the supply of the vaporized gas can be continued while the vaporization of the liquefied gas by the intermediate medium type vaporizer is stopped.

  In addition, the refrigeration refrigerant supply destination facility according to the present invention is supplied with the refrigeration refrigerant so that a refrigeration load by the refrigeration refrigerant manufactured by the method for manufacturing the refrigeration refrigerant using the intermediate medium vaporizer is applied. A refrigerating refrigerant supply destination facility, a cooling means for applying another refrigerating load to the refrigerating refrigerant supply destination facility, and the cooling means according to the increase or decrease of the refrigerating load due to the refrigerating refrigerant And a control means for imparting.

  According to the above configuration, the refrigeration load caused by the refrigeration refrigerant cooled by the cold recovered from the liquefied gas fluctuates in linkage with the vaporization load of the liquefied gas. By applying another refrigeration load, the total refrigeration load of the refrigeration refrigerant supply destination facility can be adjusted. In addition, it is possible to suppress an increase in running cost by operating the cooling means only when adjusting the total refrigeration load of the refrigeration refrigerant supply destination facility.

According to the method for producing a refrigeration refrigerant and the refrigeration refrigerant supply destination facility using the intermediate medium type vaporizer of the present invention, the intermediate medium that recovered the cold heat of the liquefied gas is liquefied to cool the refrigeration refrigerant to a predetermined temperature. The refrigerant can be used for a refrigerator, an air conditioner and the like. And, by using such an intermediate medium type vaporizer as a vaporizer for cold / heat recovery of the medium / small class, the running cost and CO ₂ can be sufficiently reduced in the vaporizer for cold / heat recovery of the medium / small class. Can do.

It is the schematic which shows the cold-heat recovery LNG vaporization equipment and freezer using an intermediate-medium type vaporizer. It is the schematic of an intermediate-medium type vaporizer. It is the schematic which arranged the hot water type LNG vaporizer in parallel with the cold-heat recovery LNG vaporization installation.

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

[First Embodiment]
(overall structure)
The manufacturing method of the refrigerating refrigerant | coolant using the intermediate medium type vaporizer by this embodiment is performed in the cold recovery LNG vaporization equipment 40 using an intermediate medium type vaporizer, as shown in FIG. The cold recovery LNG vaporization facility 40, a freezer Atsushi Nobori refrigerant R _i is a freezer refrigerant -25 ° C. from (frozen coolant supply destination equipment) 41 is supplied. In the cold recovery LNG vaporization facility 40, the temperature rising refrigerant R _i passes through the inside of the intermediate medium type vaporizer as the refrigeration refrigerant R. As a result, LNG is vaporized as will be described later. At that time, the refrigeration refrigerant R collects the cold heat of LNG and is cooled to -30 ° C. (predetermined temperature). Thereafter, frozen refrigerant R that was recovered LNG cold heat is supplied to the freezer 41 the cooled refrigerant R _O is -30 ° C. refrigeration refrigerant. The temperature of heating the refrigerant R _i is not limited to -25 ° C., the temperature of the cooling refrigerant R _O is not limited to -30 ° C..

Cold heat source freezer 41 is composed of a cooling refrigerant R _O supplied from the cold heat recovery LNG vaporization facility 40, connected to the refrigerator the freezer 41 and (cooling means) 42. Cooling refrigerant R _O by refrigeration load A, and, refrigeration load by the refrigerator 42 (other refrigeration load) B is applied to the freezer 41, respectively. The refrigeration load A due to the temperature-decreasing refrigerant R _O varies in linkage with the LNG vaporization load, while the refrigeration load B due to the refrigerator 42 is constant. Therefore, the total refrigeration load of the freezer 41 is adjusted by the refrigeration load B when the control means (not shown) controls the operation of the refrigerator 42. That is, when the total refrigeration load of the freezer 41 is insufficient due to a decrease in the refrigeration load A, the refrigerator 42 is operated by the control means so that the refrigeration load B is compensated for the shortage. When the total freezing load of the freezer 41 becomes excessive due to the increase, the operation of the refrigerator 42 is stopped by the control means so as not to give the freezing load B.

In this way, by imparting refrigeration load B to the refrigerator 42 in accordance with the increase or decrease in the refrigeration load A by cooling the refrigerant R _O, it is possible to adjust the total refrigeration load freezer 41. Moreover, the increase in running cost can be suppressed by operating the refrigerator 42 only at the time of adjustment of the total freezing load of the freezer 41.

(Configuration of intermediate medium type vaporizer)
As shown in FIG. 2, the intermediate medium type vaporizer 1 used in the cold heat recovery LNG vaporization facility 40 includes a shell 11, a heat source pipe 12 provided in the shell 11, and a heat transfer pipe 21 provided in the shell 11. And an NG warmer 30.

In the shell 11, the boiling point at atmospheric pressure is housed intermediate medium P of -40 ℃ below, some of which become the intermediate medium liquid P _L of -40 ℃ liquefied. At the bottom of the shell 11, as will be immersed in the intermediate liquid medium P _L, the heat source pipe 12 is disposed. Here, the intermediate medium P is, for example, propane, an HFC mixed refrigerant, or the like. The temperature of the intermediate liquid medium P _L is not limited to -40 ° C..

Inside the heat pipe 12, as a heat source for evaporating the intermediate liquid medium P _L, warm refrigerant R _i from the freezer 41 -25 ° C. is supplied. Heating the refrigerant R _i passes through the heat source pipe 12 as refrigeration refrigerant R, an intermediate liquid medium P _L and to the heat exchanger. Frozen refrigerant R and the intermediate liquid medium P _L that has exchanged heat evaporates, rises next intermediate medium gas P _G of -40 ° C., as a heat source for vaporizing the LNG. On the other hand, the intermediate liquid medium P _L and refrigeration refrigerant R that has exchanged heat is cooled to -30 ° C. (predetermined temperature), it is supplied to the freezer 41 the cooled refrigerant R _O. Here, the freezing refrigerant | coolant R is EG system brine, PG system brine, and organic acid salt system brine, for example, and freezing temperature is -20 degrees C or less. Brine is an antifreeze containing saline as a component. The temperature of the intermediate medium gas P _G is not limited to -40 ° C..

A heat transfer tube 21 to which LNG at −140 ° C. is supplied is disposed in the upper part of the shell 11. LNG flowing heat transfer tube 21 is an intermediate medium gas _{P G} exchanging heat evaporated warmed outside the heat transfer tube 21, is sent to the NG tubing 31 as NG of -50 ° C.. On the other hand, the intermediate medium gas P _G that LNG and the heat exchange, fall is condensed by the recovery of the LNG cold intermediate liquid medium P _L becomes, the liquid reservoir portion is a lower portion of the shell 11. That is, the intermediate medium P repeats liquefaction and gasification. In addition, the temperature of LNG is not limited to -140 degreeC, The temperature of NG is not limited to -50 degreeC.

  The NG warmer 30 is supplied with hot water at 60 ° C. as a heat source from the outside (for example, a hot water boiler). The -50 [deg.] C. NG supplied from the NG pipe 31 to the NG heater 30 is further heated to 10 [deg.] C. by this hot water and sent to an NG supply destination (for example, a boiler). On the other hand, the warm water that warms NG becomes 40 ° C. warm water and is discharged from the NG warmer 30. The temperature of NG sent to the NG supply destination is not limited to 10 ° C., and the temperature of hot water supplied to and discharged from the NG heater 30 is not limited to 60 ° C. and 40 ° C.

In order to link the LNG vaporization amount and the recovery cold quantity is sensed pressure intermediate medium gas P _G at the pressure sensor 32, so that the pressure is constant at all times, refrigeration refrigerant discharged from the heat source pipe 12 (Cooling refrigerant) The flow rate of R 2 _O is adjusted by the control valve 33.

(Operation of intermediate medium type vaporizer)
Next, a method for producing a refrigeration refrigerant using the intermediate medium type vaporizer 1 will be described through the operation of the intermediate medium type vaporizer 1.

First, as shown in FIG. 2, heating refrigerant R _i of -25 ° C. from the freezer 41 to the heat source pipe 12 is supplied. A refrigeration refrigerant R passing through the heat source pipe 12, by heat exchange with the intermediate medium liquid P _L in the shell 11, the intermediate medium gas P _G next rise of the intermediate liquid medium P _L of -40 ℃ evaporated to -40 ℃ To do.

-140 of ° C. LNG passing through the heat transfer tube 21 is evaporated warmed to an intermediate medium gas _{P G} heat exchange outside the heat transfer tube 21, via the NG tubing 31 as NG of -50 ° C. NG It is sent to the warmer 30. On the other hand, the intermediate medium gas P _G that LNG and the heat exchange, fall is condensed by the recovery of the LNG cold intermediate liquid medium P _L becomes, the liquid reservoir portion is a lower portion of the shell 11. Further, the refrigeration refrigerant R that intermediate liquid medium P _L heat exchange collected of LNG cold is cooled to -30 ° C. (predetermined temperature), is supplied to the freezer 41 the cooled refrigerant R _O. In this way, the cold heat of LNG is recovered in the refrigeration refrigerant R.

In this way, the intermediate medium P having a boiling point of −40 ° C. or less under normal pressure and the refrigeration refrigerant R having a freezing temperature of −20 ° C. or less are subjected to heat exchange, whereby the intermediate medium P evaporated in the low temperature region below zero is LNG is evaporated in a low temperature region below zero. At this time, the intermediate medium P that has recovered the cold energy from the LNG is liquefied to cool the refrigeration refrigerant R to a predetermined temperature (−30 ° C.), so that the refrigeration refrigerant R can be used for a refrigerator, an air conditioner, or the like. Further, by using such an intermediate medium type vaporizer 1 as a medium-to-small class cold energy recovery vaporizer, the running cost and CO ₂ can be sufficiently reduced in the medium-to-small class cold energy recovery vaporizer. be able to.

  The -50 ° C. NG supplied from the heat transfer tube 21 to the NG heater 30 is heated to 10 ° C. by 60 ° C. hot water passing through the NG heater 30 and is supplied to the NG supply destination (for example, boiler). Sent out. The warm water in which NG is heated is lowered to 40 ° C. and discharged from the NG heater 30.

  Thus, by heating NG discharged | emitted from the inside of the heat exchanger tube 21, NG of desired temperature can be supplied to a supply destination.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. This embodiment is different from the first embodiment in that a hot water LNG vaporizer (liquefied gas vaporizer) 50 that vaporizes LNG by heat from a heat source is arranged in the cold recovery LNG vaporization facility 40 in parallel. Yes.

  LNG is supplied to the cold recovery LNG vaporizer 40 and the hot water LNG vaporizer 50 in parallel. Hot water is supplied to the hot water LNG vaporizer 50 as a heat source for vaporizing LNG. The cold heat recovery LNG vaporization facility 40 vaporizes LNG using the refrigeration refrigerant R and discharges NG. On the other hand, the hot water type LNG vaporizer 50 vaporizes LNG using warm water and discharges NG.

  In the LNG supply path, a switching valve 51 a is provided on the upstream side of the cold recovery LNG vaporization equipment 40, and a switching valve 51 b is provided on the upstream side of the hot water LNG vaporizer 50. Normally, the switching valves 51 a and 51 b are controlled so that LNG is supplied only to the intermediate medium type vaporizer 1 of the cold recovery LNG vaporization facility 40 and LNG is not supplied to the hot water type LNG vaporizer 50. The control of the switching valves 51a and 51b may be automatic or manual.

  The refrigeration load A (see FIG. 1) applied to the freezer 41 by the intermediate medium type vaporizer 1 of the cold recovery LNG vaporization equipment 40 varies in linkage with the LNG vaporization load by the intermediate medium type vaporizer 1. Therefore, when the refrigeration load A by the intermediate medium carburetor 1 falls below the LNG vaporization load, the LNG vaporization load by the intermediate medium carburetor 1 is lowered to balance the refrigeration load A and the LNG vaporization load. The switching valves 51a and 51b are controlled so that the supply amount of LNG to the intermediate medium type carburetor 1 is decreased and the supply amount of LNG to the hot water LNG vaporizer 50 is increased. Thereby, the amount of LNG vaporization by the intermediate medium type vaporizer 1 decreases, and the amount of LNG vaporization by the hot water type LNG vaporizer 50 increases. The decrease in the amount of LNG vaporized by the intermediate medium type vaporizer 1 is supplemented by the increase in the amount of LNG vaporized by the hot water type LNG vaporizer 50. Thereafter, when the reduced refrigeration load A has recovered, an intermediate medium carburetor is used to increase the LNG vaporization load in accordance with the degree of recovery and to balance the refrigeration load A and the LNG vaporization load. The switching valves 51a and 51b are controlled so that the amount of LNG supplied to 1 is increased and the amount of LNG supplied to the hot water LNG vaporizer 50 is decreased. Thereby, the amount of LNG vaporization by the intermediate medium type vaporizer 1 increases, and the amount of LNG vaporization by the hot water type LNG vaporizer 50 decreases. As described above, the total amount of LNG vaporized is adjusted.

  In addition, when the refrigeration load A by the intermediate medium carburetor 1 becomes zero, in order to make the LNG vaporization load by the intermediate medium carburetor 1 zero, supply of LNG to the intermediate medium carburetor 1 is performed. The switching valves 51a and 51b are controlled to stop and supply LNG only to the hot water LNG vaporizer 50. Thereby, although LNG is no longer vaporized by the intermediate medium type vaporizer 1, since LNG is vaporized by the hot water type LNG vaporizer 50 as a backup of the intermediate medium type vaporizer 1, the supply of NG is continued.

  Thus, in parallel with the vaporization of LNG by the intermediate medium type vaporizer 1, LNG is vaporized by the hot water type LNG vaporizer 50, and the hot water type LNG is changed according to the increase or decrease of the amount of vaporization of LNG by the intermediate medium type vaporizer 1. By increasing or decreasing the amount of LNG vaporized by the vaporizer 50, the total amount of LNG vaporized can be adjusted. Further, by using the hot water type LNG vaporizer 50 as a backup for the intermediate medium type vaporizer 1, the supply of NG can be continued while the vaporization of LNG by the intermediate medium type vaporizer 1 is stopped.

  Since other configurations are the same as those of the first embodiment, the description thereof is omitted.

(Modification of this embodiment)
The embodiment of the present invention has been described above, but only specific examples are illustrated, and the present invention is not particularly limited, and the specific configuration and the like can be appropriately changed in design. Further, the actions and effects described in the embodiments of the invention only list the most preferable actions and effects resulting from the present invention, and the actions and effects according to the present invention are described in the embodiments of the present invention. It is not limited to what was done.

For example, although LNG was used as the liquefied gas, the liquefied gas may be liquefied ethylene, LO ₂ (liquefied oxygen), LN ₂ (liquefied nitrogen), or the like.

  Further, in the second embodiment, normally, LNG is supplied only to the intermediate medium type vaporizer 1 of the cold recovery LNG vaporization facility 40 and LNG is not supplied to the hot water type LNG vaporizer 50. It is not limited to a structure, The structure by which LNG is always supplied to both may be sufficient. In this case as well, the total amount of LNG vaporized can be adjusted by increasing or decreasing the amount of LNG vaporized by the hot water LNG vaporizer 50 in accordance with the increase or decrease of the amount of LNG vaporized by the intermediate medium vaporizer 1.

  In the second embodiment, the liquefied gas vaporizer provided in the cold recovery LNG vaporization facility 40 is not limited to the hot water LNG vaporizer 50 using hot water, and may use a heat source medium such as seawater. Good.

DESCRIPTION OF SYMBOLS 1 Intermediate medium type vaporizer 11 Shell 12 Heat source pipe 21 Heat transfer pipe 30 NG warmer 31 NG piping 32 Pressure sensor 33 Control valve 40 Cold-heat recovery LNG vaporization equipment 41 Freezer (refrigerant supply destination equipment)
42 Refrigerator (cooling means)
50 Hot water type LNG vaporizer (liquefied gas vaporizer)
51a, 51b selector valves A, B refrigeration load P intermediate medium P _G intermediate medium gas P _L intermediate medium liquid R refrigeration refrigerant R _i warm refrigerant R _O cooled refrigerant

Claims (4)

A shell containing an intermediate medium having a boiling point of −40 ° C. or lower under normal pressure and a freezing temperature supplied from the outside provided in the shell so as to be immersed in the liquid intermediate medium is −20 ° C. or lower. Production of refrigeration refrigerant using an intermediate medium type vaporizer provided with a heat source pipe through which the refrigeration refrigerant passes through and a heat transfer pipe provided in the shell through which liquefied gas supplied from the outside passes through the inside A method,
The liquid intermediate medium in the shell and the refrigeration refrigerant in the heat source pipe are heat-exchanged to evaporate the liquid intermediate medium in the shell, and the refrigeration refrigerant is cooled to a predetermined temperature in the heat source pipe. And a process of
Heat exchange between the liquefied gas in the heat transfer tube and the evaporated intermediate medium in the shell evaporates the liquefied gas in the heat transfer tube and liquefies the intermediate medium evaporated in the shell. Process,
The manufacturing method of the refrigerating refrigerant | coolant using the intermediate-medium type vaporizer characterized by having.   The method for producing a refrigeration refrigerant using an intermediate medium vaporizer according to claim 1, further comprising a step of heating the evaporated liquefied gas discharged from the heat transfer tube. A liquefied gas vaporizer provided in parallel to the intermediate medium vaporizer, to which a heat source and the liquefied gas are supplied from the outside;
The method for producing a refrigeration refrigerant using an intermediate medium type vaporizer according to claim 1 or 2, further comprising a step of vaporizing the liquefied gas with heat of the heat source in the liquefied gas vaporizer. The said refrigeration refrigerant | coolant is supplied so that the refrigeration load by the said refrigeration refrigerant | coolant manufactured with the manufacturing method of the refrigeration refrigerant | coolant using the intermediate medium type vaporizer of any one of Claims 1-3 may be provided. Refrigeration refrigerant supply facility,
Cooling means for applying another refrigeration load to the refrigerant supply destination facility;
Control means for applying the other refrigeration load to the cooling means in accordance with an increase or decrease in the refrigeration load due to the refrigeration refrigerant;
A refrigeration refrigerant supply destination facility characterized by comprising:

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