Generator-condenser heat exchange coupled auto cascade absorption refrigeration cycle system

Abstract

The application discloses a generator-condenser heat exchange coupled self-recovery cascade absorption refrigeration cycle system. Based on the self-recovery cascade absorption refrigeration cycle, non-azeotropic mixed refrigerant and absorbent are used as working medium. In the condenser, the mixed refrigerant releases a large amount of temperature glide heat, and the heat is effectively recovered by establishing a coupling heat exchange process between the generator and the condenser, thereby reducing the heating amount of the generator in the system, and improving the COP of the cycle. In addition, the system can also adjust the refrigeration temperature by replacing the mixed refrigerant, and the refrigeration temperature range can be from near room temperature to below-100 DEG C, which has the characteristics of flexible refrigeration temperature adjustment. The application optimizes the self-recovery cascade absorption refrigeration cycle configuration by reasonably arranging the generator-condenser coupling heat exchanger, realizes the significant improvement of the refrigeration efficiency, has the advantages of energy saving and environmental protection, and provides a wide refrigeration temperature adjustment range, which is suitable for various application scenarios.

Description

Technical Field

[0001] The present invention relates to the technical field of absorption refrigeration, and in particular to a self-cascade absorption refrigeration cycle system with generator-condenser heat exchange coupling. Background Art

[0002] The widespread ineffective utilization of low-grade waste heat below 350°C is one of the main causes of high energy consumption. Low- and medium-grade thermal energy exists in a wide variety of forms, including industrial waste heat, ocean thermal energy, geothermal energy, and solar thermal energy. Currently, this low-grade heat is typically discarded. Effectively recycling this low-grade heat can significantly improve energy efficiency and significantly reduce thermal pollution.

[0003] Absorption refrigeration cycles can effectively utilize low-grade heat and produce a cooling effect. The self-cascade absorption refrigeration cycle applies the self-cascade principle to the traditional single-stage absorption refrigeration cycle. Compared to the single-stage absorption refrigeration cycle, at the same heat source driving temperature and cooling temperature, the self-cascade absorption refrigeration cycle can achieve lower cooling temperatures and a wider temperature adjustment range, significantly improving its application scenarios and applicability to low-grade heat sources. For example, it can provide low-temperature pre-cooling temperatures for the liquefaction of clean energy gases such as hydrogen and natural gas, thereby reducing the specific power consumption of the liquefaction process and promoting the development of clean energy.

[0004] However, while the self-cascade process can achieve lower refrigeration temperatures, the coefficient of performance (COP) is significantly reduced because a portion of the refrigerant's cooling capacity is used for self-precooling within the cycle. Therefore, the self-cascade absorption refrigeration cycle urgently needs to overcome the performance bottleneck of low COP.

[0005] For absorption refrigeration cycles, since the heat emitted during the absorption process overlaps with the solution heating temperature zone, an effective way to improve COP is to establish a heat coupling process between the generator and the absorber, namely Generator-Absorber Heat Exchange (GAX for short). However, although the GAX process can recycle waste heat from the absorption process, reduce the system's heat dissipation to the environment, and reduce the heat generated in the cycle, in order to achieve this process, the absorption temperature needs to be increased, resulting in a decrease in the absorbent's ability to absorb the refrigerant, thereby causing the absorption process to deteriorate. When the absorption temperature is high, GAX will significantly increase the cycle rate, which will have a negative impact on the actual operation of the system.

[0006] Since the self-cascade absorption refrigeration cycle must use a non-azeotropic mixed refrigerant, there is a significant temperature glide phenomenon in the condenser. During the condensation process, the various components of the high-temperature mixed refrigerant vapor (composed of a small amount of absorbent and mixed refrigerant components) condense step by step at different temperatures, which will emit a large amount of temperature glide heat. The condensation heat generally accounts for 40-65% of the heat input of the absorption refrigeration system (heat input from the generator and heat input from the evaporator), and this heat temperature zone overlaps with the heating temperature zone of the circulating solution. Therefore, drawing on the GAX concept, the present invention proposes to establish a generator-condenser heat exchange coupling in the self-cascade absorption refrigeration cycle, namely Generator-Condenser Heat Exchange (GCX), to effectively recover the temperature glide heat discharged by the non-azeotropic mixed refrigerant in the condenser, thereby significantly reducing the heat consumption of the generator and improving the COP.

[0007] After searching, in the field of absorption refrigeration technology, no prior art related to the self-cascade absorption refrigeration cycle system with generator-condenser heat exchange coupling conceived by the present invention has been found. Summary of the Invention

[0008] The present invention aims to address the shortcomings of existing technologies by proposing a self-cascaded absorption refrigeration cycle system with a generator-condenser heat exchange coupling. By integrating a heat exchange coupling process between the generator and condenser within the self-cascaded absorption refrigeration cycle, the present invention recovers the temperature glide heat of the non-azeotropic high-temperature mixed refrigerant vapor at the generator's gas phase outlet, thereby significantly reducing the amount of heat required to heat the generator and improving the cycle's COP.

[0009] The object of the present invention is achieved through the following technical solution: a self-cascade absorption refrigeration cycle system with generator-condenser heat exchange coupling, the system comprising:

[0010] Generator, its gas phase enters the gas-liquid separator through the generator-condenser heat exchanger GCX; the liquid dilute solution enters the absorber through the solution heat exchanger and solution expansion valve;

[0011] The liquid phase of the gas-liquid separator passes through the first throttle valve and the low-temperature side of a regenerator and then enters the absorber. The gas phase passes through the high-temperature sides of two regenerators and passes through the second throttle valve and evaporator, and then passes through the low-temperature sides of two regenerators and then enters the absorber.

[0012] In the absorber, the concentrated liquid solution is divided into two streams after passing through the solution pump, and enters the generator through the solution heat exchanger and the GCX heat exchanger respectively.

[0013] Furthermore, both the concentrated liquid solution and the dilute liquid solution include a non-azeotropic mixed refrigerant and an absorbent, and the molar proportion of the non-azeotropic mixed refrigerant in the concentrated liquid solution is higher than the molar proportion of the mixed refrigerant in the dilute liquid solution.

[0014] Furthermore, the non-azeotropic mixed refrigerant is selected from at least two of hydrofluoroalkanes, alkanes, olefins and hydrofluoroolefins.

[0015] Furthermore, the non-azeotropic mixed refrigerant is tetrafluoromethane and difluoroethane.

[0016] Furthermore, the heat source of the generator adopts low-grade thermal energy, the source of which includes at least one of industrial waste heat, industrial waste heat, ocean thermal energy, geothermal energy or solar energy.

[0017] Furthermore, the liquid phase outlet of the absorber is connected to a solution pump, which raises the solution from a low pressure to a high pressure state and then separates the solution into two streams.

[0018] Furthermore, a distillation device is installed between the generator and the generator-condenser heat exchanger GCX.

[0019] Furthermore, a condenser is installed between the generator-condenser heat exchanger GCX and the gas-liquid separator.

[0020] Furthermore, the absorbent content in the non-azeotropic mixed refrigerant vapor and the mass flow rate ratio of the hot and cold side streams of the GCX heat exchanger are regulated to maximize the refrigeration coefficient of performance (COP) of the generator-condenser coupled heat exchange cascade absorption refrigeration (GCX-ACAR) cycle.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) By recovering the temperature glide condensation heat of the non-azeotropic mixed refrigerant components, the refrigeration coefficient of performance (COP) of the cycle is improved. The auto-cascade absorption refrigeration (ACAR) cycle must use a non-azeotropic mixed refrigerant. The high-temperature mixed refrigerant vapor during the condensation process is composed of a small amount of absorbent and mixed refrigerant. Due to the different dew point temperatures of the different components, a large amount of temperature glide heat is discharged, and the heat temperature range overlaps with the heating temperature of the concentrated solution. This heat is directly discharged to the environment through the condenser in the ACAR cycle and is not utilized. Therefore, the present invention proposes to establish a generator-condenser heat exchange coupling (GCX) process in the ACAR cycle to effectively utilize the temperature glide condensation heat discharged by the non-azeotropic mixed refrigerant, thereby significantly reducing the heat consumption of the generator and improving the cycle COP. A simulation model of the GCX-ACAR system was built, and the calculation results showed that after establishing the generator-condenser heat exchange coupling process in the ACAR cycle, the cycle COP can be effectively improved, with the maximum COP improvement rate reaching 190%.

[0023] 2) A self-cascade absorption refrigeration system with generator-condenser heat exchange coupling can achieve efficient refrigeration at different refrigeration temperatures. Because the self-cascade absorption refrigeration system has the characteristic of flexible refrigeration temperature adjustment, applying the generator-condenser heat exchange coupling technology to this system can achieve efficient refrigeration at different refrigeration temperatures by replacing the mixed refrigerant components. For example, when using the R1234zeE+R32 / DMF working fluid pair, efficient refrigeration can be achieved in the range of -30 to -50°C; when using the R134a+R23 / DMF working fluid pair, efficient refrigeration can be achieved in the range of -50 to -80°C; and when using the R152a+R14 / DMF working fluid pair, efficient refrigeration can be achieved in the range of -90 to -115°C.

[0024] 3) The generator-condenser heat exchange coupling process does not adversely affect other processes in the cycle. Compared with the typical generator-absorber heat exchange coupling (GAX) process, although the GAX process can recover waste heat from the absorption process, thereby reducing the system's heat dissipation to the environment and reducing the amount of heat generated, in order to achieve this process, it is necessary to increase the absorption temperature, resulting in a decrease in the absorbent's ability to absorb the refrigerant, thereby causing the absorption process to deteriorate. In the generator-condenser heat exchange coupling process, the recovered heat comes from the condensation heat of the high-temperature refrigerant vapor, and this process will not have a negative impact on other links in the cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the generator-condenser heat exchange coupled self-cascade absorption refrigeration cycle system of Example 1.

[0026] Figure 2 Schematic diagram of the generator-condenser heat exchange coupled self-cascade absorption refrigeration cycle system of Example 2.

[0027] Figure 3 Schematic diagram of the generator-condenser heat exchange coupled self-cascade absorption refrigeration cycle system of Example 3.

[0028] Figure 4 Schematic diagram of the generator-condenser heat exchange coupled self-cascade absorption refrigeration cycle system of Example 4.

[0029] Figure 5 The effect of the absorbent ratio (zDMF) in the high-temperature refrigerant vapor in Example 1 on the COP of the GCX-ACAR cycle (zDMF = 0.03 / 0.1 / 0.2 / 0.3).

[0030] Figure 6The effect of the GCX heat exchanger flow ratio (β) of Example 1 on the COP of the GCX-ACAR cycle.

[0031] Figure 7 The COP comparison between the GCX-ACAR cycle and the ACAR cycle in Example 2 is shown.

[0032] Figure 8 Comparison of the cooling curves of refrigerant vapor in different cycles for the condensation process. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to the accompanying drawings and specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0034] Example 1. See Figure 1 The present invention provides a self-cascade absorption refrigeration cycle system with generator-condenser heat exchange coupling, comprising a generator 1. The top gas phase outlet of the generator is connected to the inlet of the gas-liquid separator 5 through the distillation device 2, the generator-condenser heat exchanger GCX3 and the condenser 4 in sequence, and the bottom liquid phase outlet of the gas-liquid separator is connected to the low-temperature side inlet of the first regenerator 7 through the first throttle valve 6; the top gas phase outlet of the gas-liquid separator 5 is connected to the low-temperature side inlet of the first regenerator 7 through the high-temperature side of the first regenerator 7, the high-temperature side of the second regenerator 8, the second throttle valve 9, the evaporator 10 and the low-temperature side of the second regenerator 8. The low-temperature side outlet of the first regenerator 7 is connected to the gas phase inlet end of the absorber 11. The bottom liquid phase outlet of the generator 1 is connected to the liquid phase inlet of the absorber 11 through the solution heat exchanger 12 and the solution expansion valve 13. The liquid phase outlet at the bottom of the absorber is divided into two streams after passing through the solution pump 14. One stream is connected to the inlet of the generator 1 through the low temperature side of the solution heat exchanger 12; the other stream is connected to the inlet of the generator 1 through the low temperature side of the GCX heat exchanger 3.

[0035] The inlet of the generator 1 is a concentrated solution;

[0036] The liquid phase outlet at the bottom end of the generator 1 is a dilute solution;

[0037] The concentrated solution and the dilute solution both include a mixed refrigerant and an absorbent, and the molar ratio of the mixed refrigerant in the concentrated solution is higher than the molar ratio of the mixed refrigerant in the dilute solution.

[0038] The absorbent may be selected from at least one of an organic solvent, an ionic liquid, a deep eutectic solvent, and a refrigeration oil, including N,N-dimethylformamide (DMF), N,N-dimethylacetamide, triethylene glycol dimethyl ether, α-pyrrolidone, and the like;

[0039] The non-azeotropic mixed refrigerant may be selected from at least two of hydrofluoroalkanes, alkanes, olefins and hydrofluoroolefins;

[0040] The generator-condenser heat exchange coupled self-cascade absorption refrigeration cycle system can use low-grade thermal energy as the heat source of the generator, and its source may include at least one of industrial waste heat, industrial waste heat, ocean thermal energy, geothermal energy, solar energy, etc., or other forms of low-grade thermal energy.

[0041] Each throttle valve in the present invention can be a capillary tube, a manual throttle valve, an automatic throttle valve, or other forms of throttle valves.

[0042] The internal structure of the condenser can be a floating head type, a fixed tube sheet type, a U-shaped tube sheet type, a plate type, a sleeve type or a shell and tube type.

[0043] The absorber may be a spray type, a packing type, a falling film type, or other types of absorbers.

[0044] The solution pump can raise the solution from low pressure to high pressure, which is similar to the solution pump used in the traditional absorption refrigeration system.

[0045] The distillation device may be composed of three parts, namely, a stripping section, a rectifying section and a rectifying condenser, or may be a distillation device in other forms.

[0046] Each of the regenerators may be a plate-fin multi-channel heat exchanger or other forms of heat exchangers.

[0047] In this example, the mixed refrigerant is a non-azeotropic refrigerant composed of R14 (tetrafluoromethane) and R152a (difluoroethane), and the absorbent is N,N-dimethylformamide (DMF). The basic cycle parameters given during the analysis are a generation temperature of 200°C, a condensation temperature of 30°C, an absorption temperature of 30°C, a cooling temperature of -105°C, and a generation pressure of 800 kPa. The molar proportion of DMF in the circulating concentrated solution is 95%.

[0048] For the generator-condenser coupled heat exchange auto-cascade absorption refrigeration (GCX-ACAR) cycle, there are two main variables that significantly affect the condenser-generator coupled heat exchange process and thus the COP of the cycle: the absorbent DMF content in the high-temperature mixed refrigerant vapor at the generator gas phase outlet and the mass flow rate ratio of the hot and cold side streams of the GCX heat exchanger.

[0049] See also Figure 5The figure shows the variation trend of the COP of the GCX-ACAR cycle with the molar ratio of R14 in the refrigerant components when the molar content of DMF (zDMF) in the high-temperature mixed refrigerant vapor at the gas phase outlet of the generator in Example 1 is 0.03, 0.1, 0.2 and 0.3, as well as the COP improvement rate compared to the ACAR cycle. By adjusting the number of distillation trays and the cooling water flow rate of the distillation device in Example 1, the molar content of DMF (zDMF) in the high-temperature mixed refrigerant vapor can be adjusted. Figure 5 It can be seen that within the studied operating conditions, the GCX-ACAR cycle improves the COP by approximately 10-105% compared to the ACAR cycle. The COP improvement of the GCX-ACAR cycle increases continuously with increasing zDMF. For example, when zDMF is 0.03, the COP improvement is approximately 10-14%, while when zDMF is 0.3, the COP improvement is approximately 70-110%. Regarding the refrigeration coefficient of performance (COP) of the GCX-ACAR cycle, as zDMF increases from 0.03 to 0.3, the peak COP of the GCX-ACAR cycle increases continuously from 0.0262 to 0.0290.

[0050] To analyze the effect of the GCX heat exchanger cold-to-hot flow ratio on cycle performance, the mass flow ratio of the GCX heat exchanger's cold-to-hot flow is defined as β, as shown below. The COP trends of the GCX-ACAR cycle were studied for GCX flow ratios of 0.5, 1, 1.5, and 2.

[0051]

[0052] Where: β is the mass flow rate ratio of the GCX cold side to the hot side stream; m 20 is the mass flow rate at the cold side inlet of the GCX heat exchanger, kg / h; m1 is the mass flow rate at the hot side inlet of the GCX heat exchanger, kg / h.

[0053] See also Figure 6 This figure shows the effect of flow ratio β on the COP of the GCX-ACAR cycle at different zDMF contents in Example 1, and compares it with the COP of the ACAR cycle. As can be seen, the COP of the GCX-ACAR cycle improves compared to the ACAR cycle at all flow ratios, validating the effectiveness of coupled generator-condenser heat exchange in improving cycle COP. Furthermore, under various zDMF content conditions, an optimal flow ratio of approximately 1.5 exists, at which the COP of the GCX-ACAR cycle reaches its maximum.

[0054] Example 2, see Figure 2. The self-cascade absorption refrigeration system with generator-condenser heat exchange coupling can also be installed without the distillation device that must be used in the traditional self-cascade absorption refrigeration cycle. The above analysis shows that although the distillation device can reduce the DMF content (i.e. zDMF) in the high-temperature mixed refrigerant vapor, theoretically less DMF in the ACAR cycle refrigerant can achieve a greater throttling effect. However, for the GCX-ACAR cycle, the reduction in the DMF content in the high-temperature mixed refrigerant vapor also causes the hot side stream flow and inlet temperature of the GCX heat exchanger to decrease, and the heat recovery of the GCX heat exchanger is reduced, which has a negative impact on COP. Therefore, the GCX-ACAR cycle can still achieve efficient operation after removing the distillation device.

[0055] See also Figure 7 , calculated as the COP of the GCX-ACAR system without a distillation unit in Example 2 varies with the molar ratio of R14 in the mixed refrigerant. The basic cycle parameters given during the calculation are a generation temperature of 200°C, a condensation temperature of 30°C, an absorption temperature of 30°C, a refrigeration temperature of -105°C, and a generation pressure of 800 kPa. As can be seen from the figure, within the study range, the maximum COP of the GCX-ACAR system without a distillation unit is 0.029. At this time, the molar ratio of refrigerants R14 and R152a in the concentrated solution at the absorber outlet is 36:64, which is a 185% improvement in the COP compared to the ACAR cycle without a distillation unit.

[0056] Example 3, see Figure 3 . The self-cascade absorption refrigeration system with generator-condenser heat exchange coupling can also be installed without the condenser that must be used in the traditional self-cascade absorption refrigeration cycle. In the GCX heat exchanger, the flow ratio of the hot and cold side fluids is within a reasonable range. Since the temperature of the high-temperature refrigerant vapor is close to the temperature of the concentrated solution at the outlet of the solution pump after passing through the GCX heat exchanger, and the temperature of the concentrated solution at the outlet of the solution pump is close to the temperature of the cooling water in the absorber, that is, the hot side outlet temperature of the GCX heat exchanger is close to the temperature of the cooling water. Therefore, after the condenser is removed from the GCX-ACAR cycle, the high-temperature mixed refrigerant stream can still be effectively condensed in the GCX heat exchanger, so the cycle can still operate efficiently.

[0057] Example 4, see Figure 4 The generator-condenser heat exchange coupled self-cascade absorption refrigeration system can also be installed without the distillation device and condenser that must be used in the traditional self-cascade absorption refrigeration cycle.

[0058] See also Figure 8, the figure shows the cooling curves of three refrigerant vapors in the condensation process, namely R152a+R14 (containing 3% DMF, the molar ratio of R152a to R14 is 7:3), NH3 (containing 1% H2O) and H2O, which represent the GCX-ACAR cycle, ammonia water cycle and lithium bromide water cycle respectively. The inlet temperature of the three refrigerant vapors is 100°C, and the outlet temperature is 30°C. It can be seen from the figure that when the refrigerant is water, since the phase change process of the elemental component is a constant temperature process, the entire condensation process is basically at 40°C, and the solution heating process is basically in a single-phase temperature change heating process, so it is difficult to effectively utilize the constant temperature condensation heat. For the NH3 refrigerant in the ammonia cycle, since a small amount of H2O is usually present in the refrigerant, there is a certain amount of variable temperature heat dissipation in the initial stage of condensation. However, due to the low H2O content (to prevent H2O from solidifying and clogging the pipeline when evaporating below 0°C), after the small amount of H2O condenses, the remaining NH3 vapor enters a constant temperature condensation stage of approximately 35°C. For the R152a+R14 mixed refrigerant in the GCX-ACAR cycle, since both refrigerants account for a high proportion, the condensation process smoothly reduces the temperature from 100°C to 30°C as heat is discharged, which can achieve a good temperature match with the variable temperature heating process of the solution. This figure reveals the fundamental reason why generator-condenser coupled heat exchange can be established in a typical ACAR cycle.

[0059] Table 1 shows the freezing points of the absorbent and refrigerant in the GCX-ACAR cycle and compares them with the ammonia cycle, which explains why the GCX-ACAR cycle has a larger temperature glide heat.

[0060] Table 1

[0061]

[0062] The data in Table 1 shows that the absorbent (DMF) in the GCX-ACAR cycle has a relatively low freezing point of only -61°C. In this cycle, the majority of the absorbent (over 99.5%) at the outlet of the gas-liquid separator enters the first regenerator, providing pre-cooling above -50°C, without entering the evaporator. Therefore, this absorbent does not affect the throttling and cooling effect of the refrigerant stream before the evaporator, nor does it pose the risk of freezing and clogging the piping. Consequently, the high-temperature refrigerant vapor in the GCX-ACAR cycle can contain a higher proportion of absorbent, thereby increasing the heat rejection of the mixed refrigerant vapor in the GCX heat exchanger. In contrast, the absorbent (water) in the ammonia cycle has a freezing point of 0°C, and there is no gas-liquid separator at the condenser outlet. Therefore, in the ammonia cycle, a high water content in the high-temperature refrigerant vapor would affect the throttling and cooling effect before the evaporator and pose the risk of clogging the piping due to water freezing. Therefore, the water content in the high-temperature refrigerant vapor in the ammonia cycle must be kept low, typically no more than 2%. This makes the temperature range of available temperature glide heat in the ammonia cycle relatively small.

[0063] The above embodiments are used to illustrate the present invention rather than to limit the present invention. Any modifications and changes made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser, characterized in that: The system includes: Generator, its gas phase enters the gas-liquid separator through the generator-condenser heat exchanger GCX; the liquid dilute solution enters the absorber through the solution heat exchanger and solution expansion valve; The gas-liquid separator, its liquid phase passes through the first throttle valve and the low-temperature side of the first regenerator and then enters the absorber, and the gas phase passes through the first regenerator, the high-temperature side of the second regenerator, the second throttle valve and the evaporator, and then passes through the second regenerator and the low-temperature side of the first regenerator and then enters the absorber; In the absorber, the concentrated liquid solution is divided into two streams after passing through the solution pump, and enters the generator through the solution heat exchanger and the generator-condenser heat exchanger GCX respectively.

2. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 1, characterized in that: The concentrated liquid solution and the dilute liquid solution both include a non-azeotropic mixed refrigerant and an absorbent, and the molar proportion of the non-azeotropic mixed refrigerant in the concentrated liquid solution is higher than the molar proportion of the mixed refrigerant in the dilute liquid solution.

3. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 2, characterized in that: The non-azeotropic mixed refrigerant is selected from at least two of hydrofluoroalkanes, alkanes, olefins and hydrofluoroolefins.

4. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 3, characterized in that: The non-azeotropic mixed refrigerant is tetrafluoromethane and difluoroethane.

5. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 1, characterized in that: The heat source of the generator adopts low-grade thermal energy, and its source includes at least one of industrial waste heat, industrial waste heat, ocean thermal energy, geothermal energy or solar energy.

6. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 1, characterized in that: The liquid phase outlet of the absorber is connected to a solution pump, which raises the solution from a low pressure to a high pressure state and then separates the solution into two streams.

7. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 1, characterized in that: A distillation device is installed between the generator and the generator-condenser heat exchanger GCX.

8. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 1, characterized in that: A condenser is installed between the generator-condenser heat exchanger GCX and the gas-liquid separator.

9. The self-cascade absorption refrigeration cycle system with heat exchange coupling between a generator and a condenser according to claim 2, characterized in that: The absorbent content in the non-azeotropic mixed refrigerant vapor and the mass flow rate ratio of the hot and cold side streams of the generator-condenser heat exchanger GCX are regulated to maximize the refrigeration coefficient of performance (COP) of the self-cascade absorption refrigeration GCX-ACAR cycle with generator-condenser coupled heat exchange.

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