CN113825957A

CN113825957A - Multi-cascade cooling system

Info

Publication number: CN113825957A
Application number: CN201980054224.1A
Authority: CN
Inventors: A·多布金; M·西特科夫斯基
Original assignee: N AM Technology Co ltd
Current assignee: N AM Technology Co ltd
Priority date: 2018-06-19
Filing date: 2019-05-07
Publication date: 2021-12-21
Also published as: IL260159A; SG11202012695RA; AU2019291673A1; MX2020013866A; EP3811000A4; IL260159B; WO2019244144A1; BR112020026171A2; JP2021527794A; EP3811000A1; US20210270499A1

Abstract

A multi-cascade refrigeration system having a refrigerant flowing in a refrigeration assembly is disclosed, the multi-cascade refrigeration system comprising: at least one first heat exchanger configured to receive the refrigerant from one of the refrigeration components and cool it with a first fluid provided by a sorption machine; and at least one second heat exchanger configured to receive the refrigerant from the at least one first heat exchanger and to regulate a temperature of the refrigerant with a second fluid provided by an auxiliary cooler. The refrigerant flows from the at least one second heat exchanger to another of the refrigeration components.

Description

Multi-cascade cooling system

Technical Field

The subject matter of the present disclosure relates generally to refrigeration. More specifically, the subject matter of the present disclosure relates to energy efficiency improvements for cooling systems.

Background

Commercial cascade equipment typically consists of one or more single-circuit refrigeration units, each of which includes a compressor, an evaporator, a condenser, an expansion valve, and a heat exchanger. Typically, the cascade devices represent dual-circuit refrigeration devices, and thus each cascade has a different refrigeration power. The heat pump may operate in a cascade cycle with various refrigerants, such as an air-precooling type of apparatus that utilizes air as the heat carrier, while the primary cooling circuit contains a compressor, a condenser, an evaporator and a three-stream heat exchanger. Such commercial cascades employ auxiliary compressors, condensers and evaporators, which may be connected to a three-stream heat exchanger.

Two or more electrically powered compressors are commonly used in existing cascade refrigeration units. The input electric power of the low-temperature cascade refrigeration equipment is 30-40% higher than the output refrigeration electric power.

In other commercially available systems, the refrigeration apparatus may include both a compression circuit and an absorption circuit. The absorption circuit may include an engine or a main generator combination. The drive of which provides thermal energy for the generator of the absorption circuit and electrical energy for the electric drive of the refrigeration circuit. This coupling of the refrigeration compressor to the absorption circuit prevents the above-mentioned refrigeration device from being classified as a cascade device. On the other hand, it is likely to be classified as a hybrid device, where the compressor supplies refrigerant vapor to the condenser or the medium heat exchanger.

Disclosure of Invention

According to a first aspect of the presently disclosed subject matter, a multiple cascade cooling system having a refrigerant flowing in a refrigeration assembly, the system comprising:

at least one first heat exchanger configured to receive the refrigerant from one of the refrigeration components and cool it with a first fluid provided by a sorption machine;

at least one second heat exchanger configured to receive the refrigerant from the at least one first heat exchanger and to regulate a temperature of the refrigerant with a second fluid provided by an auxiliary cooler; and is

Wherein the refrigerant flows from the at least one second heat exchanger to another of the refrigeration components.

In some exemplary embodiments, the at least one first heat exchanger and the at least one second heat exchanger are integrated into at least one dual heat exchanger, and wherein the refrigerant is cooled by the first fluid while being conditioned by the second fluid in the at least one dual heat exchanger.

In some exemplary embodiments, the at least one second heat exchanger is configured to regulate a temperature of the first fluid with the second fluid; and wherein the at least one first heat exchanger is configured to receive the first fluid from the at least one second heat exchanger to cool the refrigerant, and wherein the refrigerant flows from the at least one first heat exchanger to the other of the refrigeration components.

In some exemplary embodiments, the at least one second heat exchanger is configured to cool the second fluid with the first fluid, wherein the at least one first heat exchanger is configured to receive the cooled second fluid from the at least one second heat exchanger to cool the refrigerant, and wherein the refrigerant flows from the at least one first heat exchanger to the other of the refrigeration components.

In some exemplary embodiments, the sorbent is selected from the group consisting of: an absorption machine; an adsorption machine; and any combination thereof.

In some exemplary embodiments, the sorption machine is primarily powered by residual energy selected from the group consisting of: ash water; steam; waste gas, hot water; and any combination thereof.

In some exemplary embodiments, the second fluid is used to regulate the temperature of the refrigerant due to inconsistent temperatures of the first fluid due to volatility of residual energy.

In some exemplary embodiments, the component is a condenser and the other component is an expansion valve.

In some exemplary embodiments, the refrigerant is selected from the group consisting of: r22; R410A; r12; r134; and any combination thereof.

In some exemplary embodiments, the first fluid and the second fluid are selected from the group consisting of: water; r22; R410A; r12; r134; and any combination thereof.

According to another aspect of the presently disclosed subject matter, there is provided a method of operating a multiple cascade cooling system, the method comprising:

receiving the refrigerant from the assembly;

cooling the refrigerant with the first fluid;

adjusting the temperature of the refrigerant with the second fluid; and

flowing the refrigerant to the other component.

In some exemplary embodiments, said adjusting said temperature is adjusting said temperature of said first fluid with said second fluid.

In some exemplary embodiments, said cooling said refrigerant is cooling and adjusting said temperature of said refrigerant with said second fluid, and wherein said first fluid is cooling said second cooling.

In some exemplary embodiments, the multiple cascade cooling system is installed in a transport vehicle.

In some exemplary embodiments, the sorption machine is powered by residual energy selected from the group consisting of: radiator fluid of a vehicle engine, engine oil of a vehicle engine, exhaust gas; and any combination thereof.

In some exemplary embodiments, the auxiliary cooler is powered by an auxiliary battery.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the subject matter disclosed herein belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the presently disclosed subject matter, suitable methods and materials are described below. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

Drawings

Some embodiments of the disclosed subject matter are described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the disclosed subject matter only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the disclosed subject matter. In this regard, no attempt is made to show structural details of the disclosed subject matter in more detail than is necessary for a fundamental understanding of the disclosed subject matter, the description taken with the drawings making apparent to those skilled in the art how the several forms of the disclosed subject matter may be embodied in practice.

In the drawings:

FIG. 1 shows a block diagram of a configuration of a multiple cascade cooling system, according to some exemplary embodiments of the disclosed subject matter;

FIG. 2 shows a block diagram of another configuration of a multiple cascade cooling system, in accordance with some exemplary embodiments of the disclosed subject matter;

fig. 3 shows a block diagram of yet another configuration of a multiple cascade cooling system, according to some exemplary embodiments of the disclosed subject matter.

FIG. 4 shows a block diagram of another configuration of a multiple cascade cooling system, in accordance with some exemplary embodiments of the disclosed subject matter; and

FIG. 5 depicts a P-H diagram of a multiple cascade cooling system in accordance with some exemplary embodiments of the disclosed subject matter.

Detailed Description

Before explaining at least one embodiment of the disclosed subject matter in detail, it is to be understood that the disclosed subject matter is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The disclosed subject matter is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. The drawings are generally not drawn to scale. For purposes of clarity, unnecessary elements have been omitted in some of the drawings.

It is a technical object of the present disclosure to improve the energy efficiency of a commercial cooling system by cascading at least one heat exchanger between a condenser and an evaporator of the cooling system. In some exemplary embodiments, a heat exchanger may be added to the cooling system. The heat exchanger may utilize the residual fluid to absorb heat from the refrigerant flowing between the condenser and the evaporator of a commercially available system. One technical effect of utilizing the disclosed subject matter is to significantly reduce energy consumption by reducing refrigerant temperature using a heat exchanger.

Another technical challenge addressed by the disclosed subject matter is the utilization of the availability of residual fluids such as steam, grey water, and combinations thereof. In addition, residual fluid variability and instability are addressed, which may affect cooling system accuracy, such as set point temperature and energy consumption.

Another technical solution is to cascade at least one compressor-based cooling system outside the heat exchanger to adjust the refrigerant temperature and compensate for the variability of the residual fluid fed to the heat exchanger. It should be noted that the loss of residual fluid typically occurs during off-time. Accordingly, another aspect of the present disclosure is to maintain an energy efficient solution even without a source that continuously provides residual fluid.

One technical effect of utilizing the disclosed subject matter is efficient energy consumption of the refrigeration equipment. The most important operating parameters of a cascade refrigeration plant with two circuits are the control accuracy and the operating stability of its operating parameters.

Referring now to fig. 1, a block diagram of a first configuration of a multiple cascade cooling system 100 is shown, in accordance with some exemplary embodiments of the disclosed subject matter. The cooling system may include: a compressor 101, a condenser 102, a main heat exchanger 103, an auxiliary heat exchanger 104, an expansion valve 105, an evaporator 107, and a temperature sensor 106. Additionally, refrigerant conductive lines 111 may be used to connect the refrigeration components listed above in a circuit such as the configuration depicted in fig. 1. In some exemplary embodiments, a coolant refrigerant, such as R22, R410A, R12, R134, etc., may flow in the conductive line 111 and through the refrigeration components listed above.

In some exemplary embodiments, the coolant refrigerant flows in the circuit from the compressor 101 to the evaporator 107 in the following order: the first condenser 102, the second refrigerant circuit of the main heat exchanger 103, the third refrigerant circuit of the auxiliary heat exchanger 104 and the final expansion valve 105 are subsequently expanded into the evaporator 107. In some exemplary embodiments, the coolant refrigerant flows through the primary loop 103P of the main heat exchanger 103 and then through the primary loop 104P of the main heat exchanger 103. The coolant refrigerant can be cooled by a fluid flowing through the circuit 108 of the heat exchanger 103 (hereinafter referred to as fluid 108) and a fluid flowing in the circuit 109 of the auxiliary heat exchanger 104 (hereinafter referred to as fluid 109).

In some exemplary embodiments, as a second step in the cascade system, a primary heat exchanger 103 may be used to cool the coolant refrigerant with a fluid 108. Fluid 108 may be provided by a sorption machine (not shown). Additionally or alternatively, as a third step in the cascade system, an auxiliary heat exchanger 104 may be used to cool the coolant refrigerant with fluid 109. Fluid 109 may be provided by a commercially available cooling system that acts as an auxiliary cooling system (not shown). The sorbers typically utilize residual fluid as their energy source, where the energy consumption of both the Auxiliary Cooling System (ACS) and the sorbers is much lower than the energy consumption of the base system, i.e., the system 100 minus the two heat exchangers. It should be noted that the coefficient of performance (COP) of the system 100 is significantly improved due to the additional cooling of the coolant refrigerant with the spent residual energy of the fluid 108.

In some exemplary embodiments, as a third step of cooling in the cascade system, an auxiliary heat exchanger 104 may be used. Since the residual fluid and/or any other absorbent material supply is volatile, the auxiliary heat exchanger 104 may be connected after the main heat exchanger 103 in order to stabilize the coolant refrigerant temperature. Additionally, the auxiliary heat exchanger 104 may be used to control cooling to a desired temperature, thus acting as a regulator. This affects the overall system benefits, provides stability to its operation, and extends the useful life of the compressor and expansion valve 105. In some exemplary embodiments, the auxiliary heat exchanger 104 may be a commercially available cooling system that feeds coolant fluid into the second loop 109 in order to regulate the main refrigerant temperature and compensate for temperature losses due to lack of residual thermal uniformity.

It should be appreciated that in the event of increased residual fluid production, the dual cascade self-regulating system may not require activation of the auxiliary heat exchanger 104, where steam, grey water, etc. contribute most of the energy. However, in the absence of residual fluid, most of the workload falls on the condenser 102 and the ACS providing fluid 109, which will operate at an apparent temperature and therefore a much higher COP than commercial machines.

In some exemplary embodiments, the sorbent may utilize a solid absorbent material instead of a fluid. Additionally or alternatively, the sorption machine may be assisted with a supplemental (backup) heat reservoir (residual) that will feed heat to the machine in the absence of residual energy.

In some exemplary embodiments of the disclosed subject matter, the multiple cascade cooling system 100 may be used in a cargo transport vehicle (FTV), such as a refrigerated truck, a railroad car, a shipping container, and the like. Refrigerated FTVs are used to transport perishable goods at specific temperatures. The cooling system 100 of the present disclosure may also be used in cargo ships to maintain a particular temperature during bulk transport of, for example, meat, fish, vegetables, plants, hazardous materials, and the like.

In such an exemplary embodiment of an FTV, the cooling system 100 may be similar to the embodiment depicted in fig. 1, but the primary heat exchanger 103 and the auxiliary heat exchanger 104 may be powered differently. As a second step in the cascade system, a primary heat exchanger 103 can be used to cool the coolant refrigerant with a stream 108. Fluid 108 may be provided by a sorption machine (not shown). In some exemplary embodiments, the sorbers utilized in FTV embodiments may differ from typical stationary sorbers due to the residual energy sources they use. In an FTV embodiment, the alternative source of residual energy may be selected from the group consisting of: a radiator fluid of a vehicle engine, an oil of a vehicle engine, an exhaust gas, any combination thereof, and the like.

Additionally or alternatively, as a third step in the cascade system, an auxiliary heat exchanger 104 may be used to cool the coolant refrigerant with fluid 109. The fluid 109 may be provided by a commercially available cooling system powered by a rechargeable auxiliary battery (not shown). In some exemplary embodiments, the auxiliary battery may be used to be powered by the vehicle alternator and line power when the vehicle is parked.

The use of a sorption machine and an ACS in an FTV embodiment may significantly reduce energy consumption and thus significantly improve COP compared to commercially available refrigerated vehicles.

An additional technical effect of utilizing the FTV feature of the disclosed subject matter is to reduce the fuel consumption of the vehicle below a regulatory threshold, thereby sparing the use of biodiesel.

Referring now to fig. 2, a block diagram of a second configuration of a multiple cascade cooling system 200 is shown, in accordance with some exemplary embodiments of the disclosed subject matter. The cooling system may include refrigeration components such as a compressor 101, a condenser 102, a dual heat exchanger 110, an expansion valve 105, an evaporator 107, and a temperature sensor 106. Additionally, refrigerant conductive lines 111 may be used to connect the refrigeration components listed above in a circuit such as the configuration depicted in fig. 2. In some exemplary embodiments, a coolant refrigerant (fluid), such as R22, R410A, R12, R134, etc., may flow in the conductive line 111 and through the refrigeration components listed above.

In some exemplary embodiments, the refrigerant flows in a loop from compressor 101 to condenser 102 to double heat exchanger 110 and then to expansion valve 105, and then expands into evaporator 107. In some exemplary embodiments, the refrigerant flowing through the primary circuit 110P of the dual heat exchanger 110 may be cooled by a first fluid flowing through the first circuit 108 and a second fluid flowing in the second circuit 109 of the dual heat exchanger 110.

In some exemplary embodiments, the first fluid flowing through the first circuit 108 (hereinafter fluid 108) may be water or any of the refrigerants described above. Similarly, the second fluid (hereinafter referred to as fluid 109) flowing through the second circuit 109 may be either water or the above-described refrigerant. Fluid 108 may be provided by a commercially available sorption machine (not shown) and fluid 109 may be a typical refrigerant coolant commonly provided by an ACS (not shown).

It should be noted that the sorption machine is used to regenerate the sorption solution by removing heat from the cooling water by utilizing residual energy from steam, exhaust gas, hot water, any combination thereof, and the like. Sorption is a physical and chemical process by which one substance becomes attached to another. It should be noted that the present disclosure may utilize an absorption or adsorption machine. The absorption machine incorporates a substance in one state that changes to another state, such as a liquid absorbed by a solid or a gas absorbed by a liquid. The adsorber bonds ions and molecules to the surface of another phase, such as an agent adsorbed to the surface of a solid catalyst. For example, an adsorber incorporates a solid substance that sorbs a fluid coolant, while an adsorber incorporates a liquid substance that sorbs a gas coolant.

In some exemplary embodiments, an absorption or adsorption machine (not shown) may be used to cool the fluid 108, which then cools the coolant refrigerant (flowing into the primary loop 110P) of the dual heat exchanger 110. Therefore, by cascading the double heat exchanger 110 for further cooling the coolant refrigerant with the sorption machine using the residual energy, the coefficient of performance (COP) of the system can be improved.

Additionally or alternatively, an ACS (not shown), such as a chiller, may be used to condition the fluid 109, which then cools the coolant refrigerant (flowing into the primary loop 110P) of the dual heat exchanger 110. It should be appreciated that fluid 109 may be used to regulate the temperature of the coolant refrigerant flowing into primary loop 110P. In some exemplary embodiments, cooling and conditioning the coolant refrigerant may be performed simultaneously by fluid 108 and fluid 109, respectively.

Due to variability in the residual energy driving the sorbent, adjustments may be required. In some exemplary embodiments, residual energy, such as grey water, steam, and the like, may be accumulated during peak periods to compensate for off-peak periods to maintain a continuous supply to the sorbent. In such embodiments, fluid 109 may be used to adjust the coolant refrigerant temperature to compensate for cooling requirements and instability in the temperature of fluid 108. In other exemplary embodiments, fluid 109 may also be used to compensate for off-peak periods in systems lacking a residual energy accumulator.

In some exemplary embodiments, the coolant refrigerant of the cooling cascade may be carried out in three stages: a first phase by means of compressor 101 and condenser 102; a second stage by means of fluid 108, and a third stage by means of fluid 109. It should be noted that the second loop 109 of the dual heat exchanger 110 may be used to stabilize the coolant refrigerant temperature since the residual fluid has volatility that may affect the throughput of the sorption machine. The second loop 109 may also be used to control cooling to a desired temperature. This configuration of the cascade cooling system 200 increases the efficiency of the overall system, provides stability to its operation, and extends the useful life of the compressor 101 and expansion valve 105. In some exemplary embodiments, fluid 109 may be provided by a commercially available cooling system that feeds coolant fluid 109 to second loop 109 in order to regulate the main refrigerant temperature and compensate for temperature losses due to lack of residual thermal uniformity.

It should be appreciated that in the event of increased residual fluid production, the dual cascade self-regulating system may not require activation of the auxiliary heat exchanger 104, where steam, grey water, etc. contribute most of the energy. However, in the absence of residual fluid, most of the workload falls on the compressor 101, condenser 102 and ACS, which will operate at apparent temperatures, and therefore, the COP is much higher than that of commercially available machines. It should be noted that the COP of the cooling cascade is significantly improved by taking advantage of the energy build-up in the residual fluid.

Referring now to fig. 3, a block diagram of a second configuration of a multiple cascade cooling system 300 is shown, in accordance with some exemplary embodiments of the disclosed subject matter. The cooling system may include refrigeration components such as a compressor 101, a condenser 102, a primary heat exchanger 103, an auxiliary heat exchanger 104, an expansion valve 105, an evaporator 107, and a temperature sensor 106. Additionally, refrigerant conductive lines 111 may be used to connect the refrigeration components listed above in a circuit such as the configuration depicted in fig. 3. In some exemplary embodiments, a coolant refrigerant, such as R22, R410A, R12, R134, etc., may flow in the conductive line 111 and through the refrigeration components listed above.

In some exemplary embodiments, the coolant refrigerant (fluid) flows in a loop from compressor 101 to condenser 102 to main heat exchanger 103 and then to expansion valve 105, and then expands into evaporator 107. The coolant refrigerant flows to the expansion valve 105 via the primary circuit 103P of the main heat exchanger 103. The coolant refrigerant can be cooled in the main heat exchanger 103 by a fluid 108 provided to the circuit 108 by a sorption machine (not shown). In some exemplary embodiments, the fluid 108 first enters the auxiliary heat exchanger 104 for further cooling and temperature conditioning purposes. The fluid 108 may be conditioned in the auxiliary heat exchanger 104 by a second fluid flowing in a circuit 109 of the auxiliary heat exchanger 104.

In some exemplary embodiments, the first fluid (fluid 108) flowing through the first circuit 108 may be water or any of the refrigerants described above. Similarly, the second fluid (hereinafter referred to as fluid 109) flowing through the second circuit 109 may be either water or the above-described refrigerant.

Fluid 108 may be provided by a commercially available sorption machine (not shown) and fluid 109 may be a typical refrigerant coolant commonly provided by an ACS (not shown).

It should be noted that the sorption machine is used to regenerate the sorption solution by removing heat from the cooling water by utilizing residual energy in the form of steam, exhaust gas, hot water, any combination thereof, and the like. Sorption is a physical and chemical process by which one substance becomes attached to another. It should be noted that the present disclosure may utilize an absorption or adsorption machine. The absorption machine incorporates a substance in one state that changes to another state, such as a liquid absorbed by a solid or a gas absorbed by a liquid. The adsorber bonds ions and molecules to the surface of another phase, such as an agent adsorbed to the surface of a solid catalyst.

In some exemplary embodiments, an absorption or adsorption machine (not shown) may be used to cool the fluid 108, which then cools the coolant refrigerant of the primary heat exchanger 103 (flowing into the primary loop 103P). Therefore, by cascading the main heat exchanger 103 for further cooling the coolant refrigerant with the sorption machine utilizing the residual energy, the coefficient of performance (COP) of the system can be improved.

Additionally or alternatively, an ACS (not shown) may be used to cool fluid 109, which cools fluid 108 in primary heat exchanger 103. It will be appreciated that the fluid 109 can be used to regulate the temperature of the fluid 108 due to variability in the residual energy driving the sorbent. In some exemplary embodiments, residual energy, such as grey water, steam, and the like, may be accumulated during peak periods to compensate for off-peak periods to maintain a continuous supply to the sorbent. In such embodiments, the fluid 109 may be used to adjust the fluid 108 temperature in order to compensate for cooling requirements and instability in the fluid 108 temperature.

In some exemplary embodiments, the coolant refrigerant of the cooling cascade may be carried out in three stages: a first phase by means of compressor 101 and condenser 102; a second stage by means of fluid 108, and a third stage by means of fluid 109. It should be noted that the loop 109 of the heat exchanger 104 may be used to stabilize the temperature of the fluid 108, since the residual fluid has volatility that may affect the throughput of the sorption machine. The loop 109 may also be used to control cooling to a desired temperature. This configuration of the cascade cooling system 300 increases the efficiency of the overall system, provides stability to its operation, and extends the useful life of the compressor and expansion valve 105. In some exemplary embodiments, fluid 109 may be provided by a commercially available cooling system that feeds coolant fluid 109 to loop 109 to regulate the temperature of fluid 108.

It should be appreciated that in the event of increased residual fluid production, the dual inline self-regulating system may not require activation of an additional cooling system that provides fluid 108, where steam, grey water, etc. contribute most of the energy.

Referring now to fig. 4, a block diagram of a fourth configuration of a multiple cascade cooling system 400 is shown, in accordance with some exemplary embodiments of the disclosed subject matter. It should be noted that the following fourth configuration of the multiple cascade cooling system 400 may be suitable for applications where the supply of residual energy is very unstable and may be frequently interrupted.

The cooling system may include refrigeration components such as a compressor 101, a condenser 102, a primary heat exchanger 104, an auxiliary heat exchanger 103, an expansion valve 105, an evaporator 107, and a temperature sensor 106. Additionally, refrigerant conductive lines 111 may be used to connect the refrigeration components listed above in a circuit such as the configuration depicted in fig. 4. In some exemplary embodiments, a coolant refrigerant, such as R22, R410A, R12, R134, etc., may flow in the conductive line 111 and through the refrigeration components listed above.

In some exemplary embodiments, the coolant refrigerant flows in a loop from compressor 101 to condenser 102 to main heat exchanger 104 and then to expansion valve 105, and then expands into evaporator 107. The coolant refrigerant flows to the expansion valve 105 via the primary circuit 104P of the main heat exchanger 103. The coolant refrigerant may be cooled in the main heat exchanger 104 by a fluid 109 provided by an ACS (not shown), such as an air conditioning system, chiller, etc. Stream 109 can be used to cool the coolant refrigerant flowing into the primary loop 104P of the main heat exchanger 104. In some exemplary embodiments, stream 109 may be fed to auxiliary heat exchanger 103 via loop 109 prior to entering main heat exchanger 104 for further cooling purposes. In this exemplary embodiment, the auxiliary heat exchanger 103 may be used to cool the fluid 109 with the fluid 108 provided by a sorption machine (not shown) via the circuit 108. It should be appreciated that the sorbers act as a supplemental energy source, which utilizes the residual energy to provide additional cooling to the fluid 109. In this configuration, additional cooling of fluid 109 is not mandatory for normal operation of the system of the present disclosure, however the presence of residual energy significantly reduces the energy consumption of the cooling system providing fluid 109, thereby increasing the COP of the entire cascade system. It should be noted that the fluid 109 acts as a temperature regulator, and its operation may be determined by the cooling demand of the setpoint sensor 106 and the presence of residual energy of the sorption machine.

In some exemplary embodiments, the fluid 108 may be water or any of the refrigerants described above. Similarly, the fluid 109 flowing through the circuit 109 may be either water or the above-described refrigerant. Fluid 108 may be provided by a commercially available sorption machine (not shown) and fluid 109 may be a typical refrigerant coolant commonly provided by an ACS (not shown).

In some exemplary embodiments, an absorption or adsorption machine (not shown) may be used to cool the fluid 108, which then cools the coolant refrigerant of the main heat exchanger 104 (flowing into the primary loop 104P). Therefore, by cascading the main heat exchanger 103 for further cooling the coolant refrigerant with the sorption machine utilizing the residual energy, the coefficient of performance (COP) of the system can be improved.

Additionally or alternatively, additional cooling systems (not shown), such as air conditioning systems, chillers, etc., may be used to cool the fluid 109, which cools the coolant refrigerant. It should be appreciated that the fluid 109 may also serve as a conditioner due to variability in the residual energy driving the sorbent. In some exemplary embodiments, residual energy, such as grey water, steam, and the like, may be accumulated during peak periods to compensate for off-peak periods to maintain a continuous supply to the sorbent. In such embodiments, the fluid 108 may be used to further cool the fluid 109 in order to compensate for cooling requirements and mitigate the source of the fluid 109.

In some exemplary embodiments, the coolant refrigerant of the cooling cascade may be carried out in three stages: a first phase by means of compressor 101 and condenser 102; a second stage by means of fluid 109 and a third stage by means of fluid 108. This configuration of the cascade cooling system 300 increases the efficiency of the overall system, provides stability to its operation, and extends the useful life of the compressor and expansion valve 105.

Referring now to FIG. 5, a P-H diagram of a multiple cascade cooling system is depicted in accordance with some exemplary embodiments of the disclosed subject matter. The p-h diagram is a graph with absolute pressure [ p ] on the vertical axis and specific enthalpy [ h ] on the horizontal axis. This map can be used to determine and evaluate the performance of the multiple cascade cooling system of the present disclosure relative to commercially available cooling systems. In some exemplary embodiments, the gaseous coolant flows out of the evaporator 107 (point 1) and into the compressor 101. After compression, the coolant has a higher pressure and temperature (point 2). The hot vapor flows into condenser 102 where it is cooled and condensed with slight subcooling (point 3). In contrast to the commercial cycle (condenser 102 followed by expansion valve 105 and temperature control sensor 6), the disclosed solution includes two additional circuits (103 and 104) connected in series to further cool the coolant refrigerant with

fluids

108 and 109. Thus, the cycle (subcooling) is stretched to point 3' so that the main heat treatment workload falls on the circuit 108. In this context, the sorption circuit operates at a higher temperature, which significantly increases its COP and allows the use of low-grade waste heat with maximum efficiency. A circuit 109 connected after the circuit 108 can be used to control the subcooling process by cooling the base coolant to a preset temperature (point 4') with high accuracy. This increases the cooling amount by δ Q.

The following includes test data for the exemplary configuration (100) depicted in fig. 1. The system includes basic cooling equipment, namely a compressor 101, a condenser 102, an expansion valve 105, an evaporator 107, a temperature sensor 106 connected by refrigerant conducting lines 111. The refrigeration power of the basic cooling device (with cascade unit) is about 350 kW. The following two cascaded units have been added to the base system:

a. a main heat exchanger 103 which is refrigerated by a 12KW solid sorbent (adsorbent) machine via loop 108.

b. An auxiliary heat exchanger 104, which is refrigerated through a 15KW ACS with a 4HP compressor via circuit 109.

c. Thus, the power added by the cascade loop is 27KW in total, which is less than 8% of the main system.

d. The coolant refrigerant is R22.

e. The operating temperature in the evaporator 107 was-7 ℃.

f. The average temperature of R22 at the outlet of condenser 102 was 40 ℃.

The two cascades added reduce the temperature of the coolant to 18 ℃, which increases the COP by 8%. Since the refrigeration load of the equipment is kept stable, the increase of the refrigeration capacity stops the operation of the fan and the compressor of the basic condenser, and the power consumption is gradually reduced by 12%. The economy is most remarkable during the hot days when the electricity is the most expensive.

It should be noted that in view of both the difficulty of negative temperature sorption device customization and its lower COP, a cascade circuit connection on the hot side of the refrigeration cycle can be effectively substituted for a negative temperature design sorption device.

In the example, the removal of heat from the basic refrigeration circuit at a relatively high temperature (up to +40 ℃), point 3 in fig. 5, results in an increase in the COP of both circuits added and an increase in the refrigeration capacity (δ Q) of the basic system, which is substantially close to the value of the excess refrigeration capacity. The enthalpy difference between points 3 and 3 'is equal to the enthalpy difference between points 4 and 4', and is calculated according to the following formula: δ Q ═ h_3,4-h_3',4'Wherein δ Q is the refrigeration capacity; h is_3,4Represents the enthalpy values at

points

3 and 4 of the thermodynamic p-h diagram; h is_3',4'Indicating the enthalpy values at points 3 'and 4' in the thermodynamic p-h diagram. It should be noted that the increase in the cooling capacity δ Q occurs simultaneously with the lowest consumption of electricity and contributes significantly to the increase in COP of the basic refrigeration circuit.

Such exemplary embodiments exhibit efficiency in utilizing low grade waste heat, and natural and automatic regulation due to cooperation of the two added circuits, optimizing operational control of the refrigeration appliance. The choice of the end temperature of the subcooling process (point 3' in fig. 5) is determined by the requirements of the optimization and can be achieved with great precision due to the added compression circuit. A sufficient amount of low potential waste heat can be utilized with maximum efficiency, and thus power consumption can be reduced by 30%. Reducing the run time of the compressor in the base loop can extend the life of the compressor, thereby reducing maintenance costs.

While the present subject matter has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present subject matter.

Claims

1. A multiple cascade cooling system having a refrigerant flowing in a refrigeration assembly, the system comprising:

2. The system of claim 1, wherein the at least one first heat exchanger and the at least one second heat exchanger are integrated into at least one dual heat exchanger, and wherein the refrigerant is cooled in the at least one dual heat exchanger by the first fluid while being conditioned by the second fluid.

3. The system of claim 1, wherein the at least one second heat exchanger is configured to regulate a temperature of the first fluid with the second fluid; and wherein the at least one first heat exchanger is configured to receive the first fluid from the at least one second heat exchanger for cooling the refrigerant, and wherein the refrigerant flows from the at least one first heat exchanger to the other of the refrigeration components.

4. The system of claim 1, wherein the at least one second heat exchanger is configured to cool the second fluid with the first fluid, wherein the at least one first heat exchanger is configured to receive the cooled second fluid from the at least one second heat exchanger for cooling the refrigerant, and wherein the refrigerant flows from the at least one first heat exchanger to the other of the refrigeration components.

5. The system of any one of claims 2 to 4, wherein the sorption machine is selected from the group consisting of: an absorption machine; an adsorption machine; and any combination thereof.

6. The system of claim 5, wherein the sorption machine is primarily powered by residual energy selected from the group consisting of: ash water; steam; waste gas, hot water; and any combination thereof.

7. The system of claim 5, wherein the temperature of the refrigerant is regulated with the second fluid due to a temperature inconsistency of the first fluid due to volatility of residual energy.

8. The system of claim 5, wherein the component is a condenser and the other component is an expansion valve.

9. The system of claim 5, wherein the refrigerant is selected from the group consisting of: r22; R410A; r12; r134; and any combination thereof.

10. The system of claim 5, wherein the first fluid and the second fluid are selected from the group consisting of: water; r22; R410A; r12; r134; and any combination thereof.

11. A method of operating the multiple cascade cooling system of claim 1, the method comprising:

receiving the refrigerant from the assembly;

cooling the refrigerant with the first fluid;

adjusting the temperature of the refrigerant with the second fluid; and

flowing the refrigerant to the other component.

12. The method of claim 11, wherein said adjusting said temperature is adjusting said temperature of said first fluid with said second fluid.

13. Adjusting the temperature of the refrigerant with the second fluid, and wherein the first fluid is cooling the second cooling.

14. The system of claim 5, wherein the multiple cascade cooling system is installed in a transport vehicle.

15. The system of claim 14, wherein the sorption machine is powered by residual energy selected from the group consisting of: radiator fluid of a vehicle engine, engine oil of a vehicle engine, exhaust gas; and any combination thereof.

16. The system of claim 14, wherein the auxiliary cooler is powered by an auxiliary battery.