JP2002081788A - Refrigeration cycle system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigeration cycle combined system constituted by combining a compression refrigeration cycle and an absorption refrigeration cycle using an ejector. SOLUTION: The refrigeration cycle using the ejector comprises the ejector 10, a vapor generator 11 for feeding driving pressure vapor to the ejector 10, a condenser 12, an expansion valve 14a and an evaporator 14. Returning refrigerant vapor from the evaporator 14 is sucked by pressure refrigerant introduced into the ejector 10 and sent to the vapor generator side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration (including air conditioning and heat pump cycle) system in which a compression refrigeration cycle and an absorption refrigeration cycle using an ejector are effectively combined. The present invention relates to a refrigeration cycle that has been used in general.

[0002] In the direction of energy saving accompanying global warming prevention,
There is an increasing demand for further efficiency improvements in gas air conditioning systems. The COP of the most efficient gas engine driven turbo chiller system among the currently commercialized equipment is 1.8, and the COP of the triple effect absorption water heater whose development is being promoted with high efficiency is 1.6. The degree is the limit,
Various efforts are being made to improve the COP in the future.

[0003] However, conventional high-efficiency systems include a single unit (a triple-effect absorption water heater) or a combination of a gas engine driven compression refrigerator and an exhaust heat driven absorption refrigerator shown in FIG. There is an ammonia gas refrigerator driven by an efficient gas engine, but as a result, there is a problem that the equipment cost is increased.

The conventional high-efficiency gas engine driven ammonia refrigerator shown in FIG. 5 comprises a compression refrigerator 50 using ammonia as a refrigerant and an absorption refrigerator 60 having another refrigerant and an absorbent. The compression refrigerator 50 includes a compressor 51 driven by a gas engine 52 and the compressor 5.
A condenser 54 for condensing the refrigerant vapor compressed by 1;
It comprises an evaporator 55 that evaporates the condensed refrigerant liquid through an expansion valve 14 (not shown) and forms a cold heat source B by latent heat of evaporation.

The exhaust gas from the gas engine 52 passes through an exhaust gas heat exchanger 53b and an exhaust heat recovery heat exchanger 53a at 88 ° C.
Hot water is supplied to the regenerator as a heat source water for heating to the absorption refrigerator 60 so as to obtain the cold heat source A from the evaporator. The cold heat sources A and B are connected in series, and the cold water of 12 ° C. to 7 ° C. And supply it to the outside. The condenser 54
Is cooled through a cooling tower 57. That is, the exhaust heat of the gas engine 52 of the compression chiller 50 provides a drive heating source to the absorption chiller 60 which is basically configured by heat drive, and both of them are connected in series with the chilled water source A, B is formed to supply cold water to the outside.

[0006] Incidentally, the absorption refrigerator has an absorber and a regenerator instead of a compressor, and the absorber functions to suck the compressor and the regenerator to push the compressor. The absorber has an absorbent, which draws refrigerant vapor from the evaporator and then pumps it to the regenerator. There, it is heated to generate a refrigerant from the absorbent and push it out to the condenser. The absorbent from which the refrigerant has been separated returns to the absorber. The repetition serves as a compressor. After all, the absorption refrigeration cycle is basically has mainly a heat-driven, the recovery of exhaust heat of the gas engine cooperating, the reuse formed by highly effective essential configuration, generally in H ₂ is the refrigerant OL
iBr system, or _NH 3 -H ₂ O system is used.

However, since the refrigerant of a gas engine driven compression refrigerator that supplies waste heat to the cooperating absorption refrigerator has a different composition from the refrigerant used in the absorption refrigerator, both refrigerants are used. 5 is limited to the system as shown in FIG. 5 described above. Even though each of the composites is highly efficient, it leads to a high cost as a whole, and it is not easy to hybridize beyond the combination of existing devices. .

FIG. 3 shows a composite system in which a compression refrigeration cycle driven by a gas engine is combined with a refrigeration cycle using an ejector, which is a comparative example of the present invention. (Unknown) The combined system shown in this embodiment is a refrigeration cycle in which refrigerant vapor is compressed by an ejector 10 and a compressor 18, and the exhaust heat of a driving gas engine 19 of the compressor 18 is exhausted by an exhaust heat exchanger 19a. The drive refrigerant vapor generated by the steam generator 11 via the heat recovery exchanger 19b is used as a drive source for the ejector 10, and the return refrigerant vapor from the evaporator 14 is supplied to the compressor 18 via the liquid separator 15; The ejector 10 sucks, mixes and compresses the steam by the driving force of the steam, and merges and sends them to the condenser 12. The compression refrigeration cycle includes a compressor 18 and a condenser 1
2; an expansion valve 14a; an evaporator 14; and a liquid separator 15. The condenser 12, the expansion valve 14a, and the evaporator 14 are shared with a refrigeration cycle using the ejector 10, and the return refrigerant from the evaporator 14 is provided. After the vapor is separated from the vapor by the liquid separator 15, the refrigerant vapor is compressed by the compressor 18.

In the case of the comparative combined system shown in FIG. 3, by using the exhaust heat of the prime mover as the drive source of the ejector 10 as described above, the refrigeration cycle using the ejector can perform the refrigeration driven by the exhaust heat. While the system is simplified and a compression cycle with reduced mechanical power can be obtained, the refrigerant vapor that is operated and compressed by both the compressor 18 and the ejector 10 is a system using a single refrigerant, and uses a separate refrigerant. Is impossible.

FIG. 4 shows another comparative example of the present invention. In this comparative example, the ejector 10 includes a condenser 12 and an evaporator 14.
The gas is extracted to the suction side of the ejector 10 from the gas-liquid mixed state in the intercooler 13 provided in the middle of the ejector 10, and the efficiency of the ejector 10 is improved as compared with the case of FIG. The compressor is introduced to the compressor through a liquid separator 15. Also in the case of this comparative example, as in the case of FIG. 3, the efficiency of the compression refrigeration cycle can be improved by reducing the mechanical power, and the refrigeration cycle using the ejector can be used by using the exhaust heat of the motor as the drive source of the ejector. The exhaust heat can be used, the exhaust heat utilization system can be simplified, and a compression cycle with reduced mechanical power can be obtained. On the other hand, the refrigerant vapor that is operated and compressed by both the compressor 18 and the ejector 10 is a single unit. It is limited to a system using one refrigerant. It becomes difficult to select a refrigerant according to each condition.

[0011]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a combined refrigeration cycle using an ejector and a compression refrigeration cycle, and to provide an efficient combined system thereof. It is another object of the present invention to provide a system in which each is formed as an independent system, each of which can select a different optimum working medium, and each of which can take an optimum compression form, and which can achieve high efficiency. On offer. Another object of the present invention is to provide an efficient combined system that improves the efficiency by utilizing the exhaust heat of the drive of the compressor of a compression refrigeration cycle driven by a motor.

[0012]

According to the present invention, there is provided a steam generator for generating a refrigerant vapor from a refrigerant solution by a heating source, a condenser, an expansion valve, and an evaporator. And a refrigerant cycle between the evaporator and the steam generator is provided with an ejector, and the refrigerant on the evaporator side is guided to the steam generator side by using the suction force of the ejector. And that a second refrigeration cycle configured to have a condensing function, an expansion function, and an evaporating function on a compressed refrigerant gas closed path of a compressor is independently combined with a refrigerant path different from that of the first refrigeration cycle. A characteristic refrigeration cycle system is proposed.

According to the invention, since the absorption type refrigeration cycle can be circulated with a single refrigerant using the ejector and in an independent path, the refrigeration cycle using the ejector and the compression refrigeration cycle are combined. However, since each cycle is formed as an independent system, each of them can select a different optimum working medium, each can take an optimum compression form, and high efficiency can be achieved. In particular, since water does not enter in the compression cycle, it can cope with various compressors. Also, by combining the two cycles independently, a high efficiency can be achieved by reducing the suction-discharge pressure difference on the compression cycle side, while increasing the solution pressure after absorption on the absorption cycle side by increasing the solution pressure after absorption. The pump power to the regenerator (steam generator) can be reduced.

According to a second aspect of the present invention, a refrigerant evaporation heat source of the steam generator of the first refrigeration cycle, a condensation heat source of the condenser, and an absorption heat cooling heat source of the ejector are obtained from the second refrigeration cycle. Features.

By effectively utilizing the heat source of the compression type refrigeration cycle, the heat source for heating the steam generator of the refrigeration cycle using the ejector, the heat source for condensing heat cooling of the condenser and the heat source for absorbing heat cooling of the ejector are heated and cooled. And no special heat energy is required.

According to a third aspect of the present invention, exhaust heat of a compressor of a second refrigeration cycle or a prime mover for driving the compressor is supplied to the steam generator of the first refrigeration cycle. .

[0017] Since the exhaust heat of the engine which is the prime mover for driving the compressors operating in parallel is used as the heating source for generating the refrigerant vapor which is the drive source of the ejector, a refrigerator driven by the exhaust heat is constructed. The exhaust heat of the driven compression refrigeration cycle can also be used, and the system as the exhaust heat utilization system can be simplified, and the compression cycle can be formed without using mechanical power.

According to a fourth aspect of the present invention, there is provided a steam generator for generating a refrigerant vapor from a refrigerant solution by a heating source, a condenser,
A first refrigerant system in which a single refrigerant system is circulated by the expansion valve and the evaporator;
And a refrigerant cycle between the evaporator and the steam generator is provided with an ejector, and the pressure of the steam generator is set higher at the nozzle inlet side of the ejector than at the outlet side. The refrigerant is introduced, the refrigerant vapor from the evaporator is sucked and mixed into the suction chamber, and the mixed refrigerant is guided to the steam generator.

According to the invention, the return refrigerant vapor from the evaporator is sucked and mixed into the suction chamber of the ejector by the refrigerant solution from the steam generator, which is jetted into the nozzle port of the ejector, and continues to the suction chamber. The heat is condensed again by heat absorption in the diffuser and sent to a steam generator. With this configuration, the refrigeration cycle using the ejector can use a single refrigerant as a working medium, and can also perform refrigeration at 0 ° C. or less depending on the selection of the refrigerant, and operate a parallel and independent circuit in a normal compression operation cycle. Becomes possible. Also, as described above, during the absorption process in the ejector,
By condensing, it is possible to reduce the pump power sent to the steam generator.

According to a fifth aspect of the present invention, a heat exchanger which communicates between a steam generator and an ejector and performs heat transfer between a refrigerant ejector suction path and a refrigerant ejector discharge side path is provided on the refrigerant path. Features. According to this invention, heat can be exchanged even on the refrigerant reciprocating path, and the present invention can be more effectively achieved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to an embodiment shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto, unless otherwise specified. It is only an illustrative example. FIG. 1 is a view showing an embodiment in which a gas engine driven compressor refrigeration cycle is combined with an ejector refrigeration cycle. In the configuration of the combined system shown in this embodiment on the compression refrigeration cycle side, the gas engine 19
, The heat exchanger 36 (condenser) for condensing the compressed refrigerant gas of the compressor 20, the expansion valve 22, and the diffuser 10c of the ejector 10 on the absorption cycle side. It is composed of an evaporating function section 23 for absorbing heat. The compressed refrigerant gas of the refrigerating compressor is branched and the branched refrigerant compressed gas is used as a heating source of a steam generator 11 functioning as a regenerator of an absorption cycle.

Also, the refrigeration cycle side using the ejector
A condenser that takes in a steam generator 11 functioning as a regenerator of an absorption refrigeration cycle and a cold / heat source of a gas-liquid mixed refrigerant from a return line 40 from the outlet side of the evaporator 14 on the compression cycle side to perform a condensation operation. 12, an expansion valve 14a for decompressing and expanding the refrigerant from the condenser 12, an evaporator 14 for cooling by heat exchange between the latent heat of evaporation of the ammonia working refrigerant from the expansion valve 14a and the load water, and an evaporative refrigerant from the evaporator 14 , And a heat exchanger 34 disposed so as to straddle between a refrigerant suction path 41 and a return path 42 between the ejector 10 and the steam generator 11. Form a refrigeration cycle.

The steam generator 11 takes in the heat of condensation of the compressed refrigerant discharged from the compressor 20 to generate refrigerant vapor and sends it to the condenser 12 side.
The drive refrigerant vapor is sent from 1 through the heat exchanger 34 to the suction side of the ejector 10. The generation of steam from the steam generator 11 is accompanied by heating by the heat of condensation of the compressed refrigerant gas,
This is performed by pumping heated water heated by the exhaust heat of the gas engine 19 that drives the compressor 20 with the pump 31.

In the ejector 10, its suction nozzle port 1
Due to the ejector effect of the refrigerant vapor from the vapor generator 11 ejected and introduced from the discharge chamber 0a, the return refrigerant vapor from the evaporator 14 is sucked into the suction chamber 10b of the ejector and mixed with the refrigerant vapor. After the latent heat of the evaporated refrigerant on the compression refrigeration cycle side in the diffuser 10c is removed, the refrigerant liquid discharged from the ejector 10 is returned to the steam generator side via the pump 33 and the heat exchanger 34. The heat exchanger cools the ammonia refrigerant passing through the suction path of the ejector and cools the ammonia refrigerant on the return path side to reduce the heat load on the steam generator and increase the energy of the working medium on the ejector suction side. ing.

Next, the operation of the combined cycle will be described. First, on the compression refrigeration cycle side, the discharge side temperature is 40 ° C.
The suction-discharge pressure difference is reduced so that the suction-side temperature becomes 23 ° C., thereby achieving higher efficiency. That is, the refrigerant compressed by the compressor 20 and heated to about 40 ° C. is branched and the heat exchange coil 1 of the steam generator 10 on the absorption refrigeration cycle side.
The ammonia refrigerant in the generator 10 is condensed by imparting latent heat of condensation to the ammonia refrigerant in the generator 10, is maintained at a temperature of 40 ° C., and returns to the outlet side of the condensation heat exchanger 36 as a condensed refrigerant. Compressor 2
The other refrigerants than zero are condensed in the condensing heat exchanger 36 and merge with the condensed refrigerant from the branch path.

The condensed refrigerant that has been joined is supplied to the expansion valve 2.
2 is decompressed and decompressed by the ejector 10
The heat is led to 0c and evaporated. A part of the 23 ° C. gas-liquid mixed refrigerant expanded and decompressed by the expansion valve 22 is partially guided to the condenser 12 on the absorption cycle side via the return path 40, where the refrigerant completely discharges latent heat of evaporation to form a 23 ° C. refrigerant. The gas is returned to the suction side of the compressor, and the above operation is repeated.
On the other hand, the exhaust heat of the gas engine 19 for driving the compressor 20 is heated and pumped by heating the heated water in the exhaust heat recovery path 37 via an exhaust heat exchanger 19a for exhaust heat recovery and an exhaust heat recovery heat exchanger 19b. The heat exchange coil 1 in the steam generator 11
Evaporation efficiency is further improved by supplying exhaust heat to 1b.

Next, the operation on the absorption cycle side will be described. First, the steam generator 10 receives the compressed gas refrigerant and the exhaust heat from the compression cycle side and evaporates.
The 00% ammonia refrigerant gas is sent to the condenser 12 side at 23 ° C. and 0.95 MPa. The condenser 12 exchanges heat with the gas-liquid mixed refrigerant at the outlet side of the expansion valve 22 on the compression cycle side and condenses by the latent heat of evaporation.

The condensed ammonia condensate is supplied to the expansion valve 14.
The pressure is reduced to 0 ° C. by a and introduced into the evaporator 14 to cool the load water by the latent heat of evaporation.

In the ejector 10, the steam generator 11
Of 68% ammonia refrigerant solution at 40 ° C. 0.95 MPa
After the heat is first removed by the heat exchanger 34 in the state described above, the 100% ammonia refrigerant gas from the evaporator 14 is kept at 0 ° C. 0.45 MPa by the ejector effect ejected from the suction nozzle port 10 a and introduced. After being drawn into the suction chamber 10b of the ejector and absorbed by the driving refrigerant solution, the diffuser 10c following the suction chamber 10b deprives the latent heat of the evaporated refrigerant on the compression refrigeration cycle side to condense,
A 76% ammonia refrigerant solution is discharged from the ejector 10 at 23 ° C. and 0.7 MPa.

The refrigerant solution is conveyed by a pump 33, heated in a heat exchanger 34 by thermal contact with the suction side refrigerant liquid, and then returned to the steam generator side. The heat exchanger 34 cools the ammonia refrigerant passing through the suction path 41 of the ejector 10 and heats the ammonia refrigerant on the return path 42 side, thereby reducing the heat load of the steam generator 11 and the ejector suction side working medium. Energy is increased.

According to this embodiment, the refrigerant vapor generated by the evaporator 14 is used as the vapor generator 11 functioning as a regenerator.
The structure is such that the 63-73% ammonia refrigerant solution sent from the tank is sucked and absorbed by the ejector 10 having an absorption function, and is further condensed by the latent heat of vaporization on the compression cycle side. (Regenerator), condenser 1
The heat source for absorption heat cooling of the ejector 2 and the ejector 10 is configured to be supplied from the compression cycle side.

Therefore, according to this configuration, the difference between the suction and discharge pressures can be reduced in the compression cycle, and the efficiency can be improved. In the absorption cycle,
By incorporating the ejector in the absorber, the solution pressure after absorption can be increased, and the power of the liquid pump to the regenerator can be reduced. Therefore, in the present invention, since it is constituted by two independent cycles of the absorption cycle and the compression cycle, it is possible to select the refrigerant according to each cycle.
Further, in this embodiment, the efficiency is further improved by utilizing the exhaust heat of the gas engine. As a result, simplicity and high efficiency can be achieved by combining conventional devices.

The combined system shown in FIG. 2 is another embodiment of the present invention. The combined system is closed by the compressor, the condenser 21, the expansion valve 22, and the evaporator 23 without directing the refrigerant gas of the compression cycle to the absorption cycle side. The compression refrigeration cycle of the circuit is constituted, and the steam generator heat is provided on the absorption cycle side using the brine paths 45, 46, 48 on the condenser side, and the evaporator and ejector on the absorption cycle side are provided on the evaporator side. The indirect heat application on the absorption cycle side is performed using the brine path of (1).

[0034]

As described above, the refrigeration combined system of the present invention is constituted by combining an ejector-based refrigeration cycle and a compression refrigeration cycle, and each is formed as an independent system. This is a system in which a working medium can be selected, and each of them can take an optimal compression form, and high efficiency can be achieved. Further, the efficiency is improved by utilizing the exhaust heat of the compression refrigeration cycle driven by the motor.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment in which a gas engine driven compression refrigeration cycle is combined with a refrigeration cycle using an ejector.

FIG. 2 is a schematic diagram showing a modification of FIG.

FIG. 3 is a schematic diagram showing a comparative example of FIG.

FIG. 4 is a schematic diagram showing a comparative example of FIG.

FIG. 5 is a diagram showing an example of a conventional complex system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Ejector 10a Nozzle port 10b Suction chamber 10c Diffuser 11 Steam generator 12, 21 Condenser 13 Intercooler 14, 23 Evaporator 14a, 13a, 22 Expansion valve 15 Liquid separator 16 Heat pump system 18, 20 Compressor 19 Gas engine

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Noriyuki Nishiyama 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. (72) Inventor Masahiro Oka 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas (72) Inventor Junji Matsuda 2-13-1, Botan, Koto-ku, Tokyo Inside the Maekawa Works Co., Ltd. (72) Asahi Yoshikawa 2-3-1, Botan, Koto-ku, Tokyo Co., Ltd. Inside the factory (72) Inventor Hiroyuki Suzuki 2-3-1 Botan, Koto-ku, Tokyo Inside Maekawa Corporation (72) Inventor Shuji Fukano 2-3-1, Botan, Koto-ku, Tokyo Inside Maekawa Corporation F term (reference) 3L093 BB01 BB21 BB26

Claims (5)

[Claims] 1. A first refrigeration cycle in which a single refrigerant system is circulated by a steam generator that generates refrigerant vapor from a refrigerant solution by a heating source, a condenser, an expansion valve, and an evaporator. An ejector is interposed in the refrigerant path between the evaporator and the steam generator, and the refrigerant on the evaporator side is guided to the steam generator side by using the suction force of the ejector, and the compressed refrigerant gas of the compressor is closed. A refrigeration cycle system wherein a second refrigeration cycle configured to have a condensing function, an expansion function, and an evaporating function on a road is independently combined with a different refrigerant path from the first refrigeration cycle. 2. A heat source for evaporating refrigerant in a steam generator, a heat source for condensing heat in a condenser, and a heat source for absorbing heat cooling in an ejector of the first refrigeration cycle, respectively. A refrigeration cycle system as described. 3. The refrigeration system according to claim 1, wherein exhaust heat of a compressor of a second refrigeration cycle or a prime mover for driving the compressor is supplied to the steam generator of the first refrigeration cycle. Cycle system. 4. A first refrigeration cycle in which a single refrigerant system is circulated by a steam generator that generates refrigerant vapor from a refrigerant solution by a heating source, a condenser, an expansion valve, and an evaporator. An ejector is interposed in a refrigerant path between the evaporator and the steam generator, and a refrigerant from a steam generator whose pressure is set relatively higher than an outlet side at a nozzle inlet side of the ejector is introduced to evaporate. A refrigeration cycle system wherein refrigerant vapor from a heater is sucked and mixed into a suction chamber, and the mixed refrigerant is guided to a steam generator. 5. A heat exchanger for transferring heat between a refrigerant ejector suction path and a refrigerant ejector discharge side path communicating between a steam generator and an ejector is disposed on the refrigerant path. A refrigeration cycle system as described.