An intermediate effect absorption refrigeration cycle system

Abstract

The application relates to the refrigeration technical field, in particular to an intermediate-effect absorption refrigeration cycle system, which comprises a semi-effect cycle refrigeration pipeline and a single-effect cycle refrigeration pipeline; a pressure generator module of the semi-effect cycle refrigeration pipeline is connected with a medium-pressure generator of the single-effect cycle refrigeration pipeline, the medium-pressure generator is connected with a condensing assembly of the single-effect cycle refrigeration pipeline, and the condensing assembly is connected with the pressure generator module; the pressure generator module is used for heating refrigerant solution output by the condensing assembly to generate high-temperature refrigerant steam under the driving of a heat source, and the high-temperature refrigerant steam is transmitted to the medium-pressure generator to drive refrigeration of the single-effect cycle refrigeration pipeline, and medium-temperature refrigerant steam generated by the medium-pressure generator is transmitted to the condensing assembly. The high-temperature refrigerant steam generated in the semi-effect refrigeration cycle process is used for driving the single-effect refrigeration cycle, so that the semi-effect cycle efficiency is improved, the utilization gradient of the heat source of the basic cycle is increased, and the low-grade heat energy is fully utilized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of refrigeration, in particular to an intermediate-efficiency absorption refrigeration cycle system. BACKGROUND

[0002] One of the reasons for high energy consumption is that low-grade waste heat below 70℃ is not effectively utilized. Low-grade heat energy exists in various forms, mainly including industrial waste heat, ocean thermal energy, geothermal energy, and solar thermal energy. At present, these low-grade heat energy is usually directly discarded. Effective recovery and utilization of these low-grade heat energy can significantly improve energy utilization efficiency and greatly reduce environmental heat pollution.

[0003] The traditional intermediate-efficiency refrigeration cycle is realized on the basis of the semi-efficiency cycle. The high-temperature refrigerant vapor generated is directly introduced into the cooler for cooling, and then the condensing solution output by the cooler is used to cool the object to be cooled. However, since the cooling efficiency of the cooler is fixed, when the high-temperature refrigerant vapor transmitted to the cooler is too high, the subsequent cooling based on the condensing solution still has a low coefficient of performance. Therefore, the existing intermediate-efficiency refrigeration cycle is only an improved two-stage cycle, and the problem of low refrigeration efficiency and coefficient of performance of the two-stage cycle has not been effectively solved.

[0004] Therefore, how to fully utilize low-grade heat energy has become a problem to be solved. SUMMARY

[0005] The main purpose of the present application is to provide an intermediate-efficiency absorption refrigeration cycle system, which aims to solve the technical problem of how to fully utilize low-grade heat energy.

[0006] To achieve the above-mentioned purpose, the present application discloses an intermediate-efficiency absorption refrigeration cycle system, which comprises a semi-efficiency cycle refrigeration pipeline and a single-effect cycle refrigeration pipeline.

[0007] The semi-efficiency cycle refrigeration pipeline is provided with a pressure generator module and a condensing assembly, and the single-effect cycle refrigeration pipeline is provided with a medium-pressure generator.

[0008] The pressure generator module is connected with the medium-pressure generator, the medium-pressure generator is connected with the condensing assembly, and the condensing assembly is connected with the pressure generator module.

[0009] The pressure generator module is used for heating the refrigerant solution output by the condensing assembly under the driving of a heat source, generating high-temperature refrigerant vapor, transmitting the high-temperature refrigerant vapor to the medium-pressure generator to drive the refrigeration of the single-effect cycle refrigeration pipeline, and transmitting the medium-temperature refrigerant vapor generated by the medium-pressure generator to the condensing assembly.

[0010] In an embodiment, the semi-cascade refrigeration pipeline further comprises: a low-temperature evaporator and a low-temperature absorber connected in sequence with the condensing assembly through pipelines, a heat exchanger assembly connected with the low-temperature absorber through a pipeline, and the heat exchanger assembly connected with the pressure generator module;

[0011] The low-temperature evaporator is configured to perform refrigeration on a medium to be cooled based on the refrigerant solution output by the condensing assembly, so as to convert the refrigerant solution into a first vapor;

[0012] The low-temperature absorber is configured to generate a dilute solution to be separated by absorbing the first vapor based on an absorbent, preheat the dilute solution to be separated through the heat exchanger assembly, and input the preheated dilute solution to be separated into the pressure generator module for heating.

[0013] In an embodiment, the pressure generator module comprises a high-pressure generator and a low-pressure generator connected in sequence through pipelines; and the heat exchanger assembly comprises a high-temperature heat exchanger and a low-temperature heat exchanger.

[0014] The high-pressure generator is connected with the medium-pressure generator and the high-temperature heat exchanger respectively, the low-pressure generator is connected with the high-temperature heat exchanger and the low-temperature heat exchanger respectively, and the low-temperature heat exchanger is connected with the high-temperature heat exchanger and the low-temperature absorber.

[0015] The dilute solution to be separated output by the low-temperature absorber is preheated through the low-temperature heat exchanger and the high-temperature heat exchanger and then input into the high-pressure generator.

[0016] The high-pressure generator is configured to heat the preheated dilute solution to be separated into a high-temperature refrigerant solution and a high-temperature refrigerant vapor based on the heat source, and output the high-temperature refrigerant vapor to the medium-pressure generator for heating.

[0017] The high-temperature refrigerant solution is input into the low-pressure generator for heating through the high-temperature heat exchanger.

[0018] In an embodiment, the single-cascade refrigeration pipeline further comprises: a medium-temperature heat exchanger and a high-temperature absorber connected in sequence with the medium-pressure generator through pipelines, and the high-temperature absorber connected with the low-temperature evaporator.

[0019] The medium-temperature heat exchanger is configured to preheat a concentrated refrigerant solution output by the high-temperature absorber and input the preheated concentrated refrigerant solution into the medium-pressure generator.

[0020] The medium pressure generator is configured to heat the preheated refrigerant concentrated solution based on the high temperature refrigerant vapor to generate the medium temperature refrigerant vapor, which is transmitted to the high temperature absorber via the condensing assembly and the low temperature evaporator to achieve refrigeration of the single effect cycle refrigeration pipeline.

[0021] In an embodiment, the system further comprises an intermediate evaporator and a gas-liquid separator.

[0022] The intermediate evaporator is in communication with the gas-liquid separator and the condensing assembly, respectively, and the gas-liquid separator is in communication with the high temperature absorber and the low temperature evaporator, respectively.

[0023] The intermediate evaporator is configured to refrigerate the medium to be cooled based on the refrigerant solution output by the condensing assembly, and generate and output a gas-liquid mixture to the gas-liquid separator, the gas-liquid mixture comprising medium temperature gas phase refrigerant and low temperature refrigerant solution.

[0024] The gas-liquid separator is configured to transmit the low temperature refrigerant solution to the low temperature evaporator, so that the low temperature evaporator refrigerates the medium to be cooled based on the low temperature refrigerant solution.

[0025] The gas-liquid separator is further configured to transmit the medium temperature gas phase refrigerant to the high temperature absorber, and the absorbent in the high temperature absorber absorbs the medium temperature gas phase refrigerant to form the refrigerant concentrated solution.

[0026] In an embodiment, the condensing assembly comprises a first condenser and a second condenser; and the refrigerant solution comprises a first refrigerant solution and a second refrigerant solution.

[0027] The first condenser is in communication with the medium pressure generator and the intermediate evaporator, respectively, and the second condenser is in communication with the low pressure generator and the intermediate evaporator, respectively.

[0028] The first condenser is configured to condense the medium temperature refrigerant vapor output by the medium pressure generator after heating into the first refrigerant solution, and output the first refrigerant solution to the intermediate evaporator.

[0029] The second condenser is configured to condense the low temperature refrigerant vapor output by the low pressure generator after heating into the second refrigerant solution, and output the second refrigerant solution to the intermediate evaporator.

[0030] In an embodiment, the system further comprises a first solution pump; and the first solution pump is in communication with the low temperature absorber and the low temperature heat exchanger, respectively.

[0031] The first solution pump is configured to transport the dilute solution generated by the low-temperature absorber to the low-temperature heat exchanger.

[0032] In an embodiment, the system further comprises a second solution pump; the second solution pump is respectively connected to the high-temperature absorber and the intermediate heat exchanger.

[0033] The second solution pump is configured to transport the concentrated refrigerant solution generated by the high-temperature absorber to the intermediate heat exchanger.

[0034] In an embodiment, the heat source is low-grade heat energy, including at least one of industrial waste heat, geothermal energy, and solar energy.

[0035] In an embodiment, the absorber concentration of the medium-pressure generator is greater than the absorber concentration of the high-pressure generator.

[0036] The present application discloses an intermediate-efficiency absorption refrigeration cycle system, which comprises a semi-effective cycle refrigeration pipeline and a single-effective cycle refrigeration pipeline; the semi-effective cycle refrigeration pipeline is provided with a pressure generator module and a condensing assembly, and the single-effective cycle refrigeration pipeline is provided with a medium-pressure generator; the pressure generator module is connected to the medium-pressure generator, the medium-pressure generator is connected to the condensing assembly, and the condensing assembly is connected to the pressure generator module; the pressure generator module is configured to heat the refrigerant solution output by the condensing assembly under the driving of a heat source, generate high-temperature refrigerant vapor, and transmit the high-temperature refrigerant vapor to the medium-pressure generator to drive the refrigeration of the single-effective cycle refrigeration pipeline, and transmit the medium-temperature refrigerant vapor generated by the medium-pressure generator to the condensing assembly. The present application combines semi-effective refrigeration cycle and single-effective refrigeration cycle, and drives the single-effective refrigeration cycle by the high-temperature refrigerant vapor generated in the semi-effective refrigeration cycle process. In this process, the heat source is first passed through the semi-effective cycle, and then the single-effective cycle is generated by the vapor of the semi-effective cycle, thereby realizing multiple utilization of the heat source, achieving the effect of double-effective refrigeration and improving the refrigeration efficiency, and realizing the effect of single-effective COP energy efficiency by using a lower heat source. Therefore, the present application increases the heat source utilization gradient of the basic cycle while increasing the efficiency of the semi-effective cycle, thereby realizing full utilization of low-grade heat energy. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0038] Figure 1 It is a first module block diagram of the intermediate-efficiency absorption refrigeration cycle system of the present application;

[0039] Figure 2 A second module block diagram of the intermediate-effect absorption refrigeration cycle system of the present application;

[0040] Figure 3 A third module block diagram of the intermediate-effect absorption refrigeration cycle system of the present application;

[0041] Figure 4 A fourth module block diagram of the intermediate-effect absorption refrigeration cycle system of the present application;

[0042] Figure 5 A fifth module block diagram of the intermediate-effect absorption refrigeration cycle system of the present application;

[0043] Figure 6 A configuration schematic diagram of the intermediate-effect absorption refrigeration cycle system of the present application.

[0044] Explanation of reference numerals:

[0045] 1, first solution pump; 2, low-temperature heat exchanger; 3, low-pressure generator; 4, first flow regulating valve; 5, high-temperature heat exchanger; 6, high-pressure generator; 7, first condenser; 8, second flow regulating valve; 9, intermediate evaporator; 10, gas-liquid separator; 11, third flow regulating valve; 12, low-temperature evaporator; 13, low-temperature absorber; 14, fourth flow regulating valve; 15, intermediate-pressure generator; 16, intermediate heat exchanger; 17, fifth flow regulating valve; 18, high-temperature absorber; 19, second solution pump; 20, second condenser.

[0046] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0048] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly.

[0049] In addition, the description related to "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes, for example, "A and / or B" includes A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the protection scope required by the present application.

[0050] Please refer to Figure 1 , Figure 1 A first module block diagram of an intermediate-efficiency absorption refrigeration cycle system of the present application is shown in Figure 1 In the present embodiment, the intermediate-efficiency absorption refrigeration cycle system comprises:

[0051] a semi-efficient cycle refrigeration pipeline and a single cycle refrigeration pipeline;

[0052] The semi-efficient cycle refrigeration pipeline is provided with a pressure generator module and a condensing assembly, and the single cycle refrigeration pipeline is provided with a medium-pressure generator 15;

[0053] The pressure generator module is connected with the medium-pressure generator 15, the medium-pressure generator 15 is connected with the condensing assembly, and the condensing assembly is connected with the pressure generator module;

[0054] The pressure generator module is used for heating the refrigerant solution output by the condensing assembly under the driving of a heat source, generating high-temperature refrigerant vapor, and transmitting the high-temperature refrigerant vapor to the medium-pressure generator 15 to drive the refrigeration of the single cycle refrigeration pipeline, and transmitting the medium-temperature refrigerant vapor generated by the medium-pressure generator 15 to the condensing assembly.

[0055] It should be noted that in the present embodiment, the heat source is the driving energy of the entire system. As an implementable manner, in the present embodiment, the heat source is low-grade heat energy, which refers to heat energy with relatively low temperature (usually ≤120℃) and difficult to be directly utilized, including but not limited to industrial waste heat (such as boiler flue gas waste heat), geothermal energy (such as hot spring water), solar energy.

[0056] The semi-effective cycle refrigeration pipeline is a refrigeration circuit with the pressure generator module as the core in the system, responsible for the first use of heat source energy to make the liquid condensant such as water into high-temperature water vapor, that is, the high-temperature refrigerant vapor; and the single-effect cycle refrigeration pipeline can be a refrigeration circuit with the medium-pressure generator 15 as the core in the system, using the vapor generated by the semi-effective cycle for secondary refrigeration.

[0057] The pressure generator module can be a set of devices for heating the refrigerant solution to generate high-temperature refrigerant vapor, which is a key component of the semi-effective cycle refrigeration that provides high-temperature driving vapor, and provides energy source for subsequent single-effect cycle driving. The condensing assembly can be a device (such as a condenser) for cooling and condensing the refrigerant vapor to change it from a gaseous state to a liquid state, ensuring that the refrigerant can be recycled and maintaining the continuity of the system refrigeration process.

[0058] The medium-pressure generator 15 can be a core heating device in the single-effect cycle refrigeration, which receives the high-temperature refrigerant vapor from the pressure generator module and uses its heat to heat the refrigerant solution inside itself to generate medium-temperature refrigerant vapor to drive the single-effect cycle refrigeration.

[0059] Exemplarily, the embodiment can use stainless steel pipes to seal and connect the pressure generator module and the medium-pressure generator 15, so that the high-temperature refrigerant vapor generated by the pressure generator module can be smoothly transmitted to the medium-pressure generator 15; at the same time, the medium-pressure generator 15 and the condensing assembly are sealed and connected to ensure that the medium-temperature refrigerant vapor generated by the medium-pressure generator 15 can be transmitted to the condensing assembly; in addition, the condensing assembly and the pressure generator module are connected, so that the refrigerant solution condensed by the condensing assembly can flow back to the pressure generator module, forming a complete circulation path.

[0060] In this circulation path, the pressure generator module first heats the refrigerant solution flowing back from the condensing assembly under the driving of the low-grade heat energy (such as industrial waste heat, geothermal energy, solar energy). During the heating process, the refrigerant in the refrigerant solution absorbs heat and evaporates to generate high-temperature refrigerant vapor. Then, compared with the existing intermediate-effect refrigeration cycle that directly transmits the high-temperature refrigerant vapor to the condensing assembly, the embodiment can use the pressure difference in the system and the guiding effect of the pipeline to transport the high-temperature refrigerant vapor from the pressure generator module to the medium-pressure generator 15 for heating, providing heat for the medium-pressure generator 15 and driving the single-effect cycle refrigeration pipeline to start working.

[0061] The medium-pressure generator 15 is heated by the heat of the high-temperature refrigerant vapor, and the refrigerant solution in the medium-pressure generator 15 is heated to evaporate the refrigerant in the solution to form a medium-temperature refrigerant vapor. The medium-temperature refrigerant vapor is transmitted to the condensing assembly through the connecting pipeline, and the medium-temperature refrigerant vapor is cooled by the cooling medium (such as cooling water) to condense into a liquid refrigerant solution.

[0062] Finally, the condensed refrigerant solution is returned to the pressure generator module through the connecting pipeline, and is heated again to generate high-temperature refrigerant vapor, so as to realize continuous refrigeration, thereby ensuring that the vapor transmission path is unobstructed, and realizing the effect of twice utilization of the heat source in the half-effect cycle and the single-effect cycle.

[0063] Therefore, the embodiment combines the advantages of the half-effect refrigeration cycle and the single-effect refrigeration cycle, so that the high-temperature vapor generated in the half-effect refrigeration cycle under the action of the pressure generator module drives the single-effect refrigeration cycle, which not only improves the half-effect cycle efficiency, but also increases the heat source utilization gradient of the basic cycle (single-effect cycle), fully utilizes the low-grade heat energy, improves the energy utilization efficiency, and reduces the energy waste. Therefore, the embodiment effectively reduces the temperature of the refrigerant solution received by the evaporator, improves the coefficient of performance of the evaporator, and improves the refrigeration efficiency of the entire system.

[0064] In an embodiment of the present application, referring to Figure 2 , Figure 2 is a second module block diagram of an intermediate-effect absorption refrigeration cycle system of the present application, as Figure 2 shown, the half-effect cycle refrigeration pipeline further comprises: a low-temperature evaporator 12 and a low-temperature absorber 13 which are sequentially connected with the condensing assembly according to the pipeline, and a heat exchanger assembly which is connected with the low-temperature absorber 13 according to the pipeline, and the heat exchanger assembly is connected with the pressure generator module;

[0065] The low-temperature evaporator 12 is used to refrigerate the medium to be cooled based on the refrigerant solution output by the condensing assembly, so as to convert the refrigerant solution into a first vapor;

[0066] The low-temperature absorber 13 is used to generate a dilute solution to be separated by absorbing the first vapor based on the absorbent, and the dilute solution to be separated is preheated by the heat exchanger assembly, and then the preheated dilute solution to be separated is input into the pressure generator module for heating.

[0067] It should be understood that, in the embodiment, as Figure 2 shown, the condensing assembly, the low-temperature evaporator 12, the low-temperature absorber 13, and the heat exchanger assembly can be sequentially and sealingly connected according to the flow order of the refrigerant solution and the vapor by using the pipeline, so as to ensure that the refrigerant flows in the half-effect cycle according to the preset path.

[0068] The low-temperature evaporator 12 can be a device for refrigerating the medium to be cooled in the semi-cycle refrigeration process, can receive the refrigerant solution from the condensing assembly, and can absorb the heat of the medium to be cooled by evaporation of the refrigerant solution to achieve cooling refrigeration, which is the refrigeration execution component of the semi-cycle. The first steam can be the steam formed by the evaporation of the refrigerant solution after the heat exchange between the low-temperature evaporator 12 and the medium to be cooled, absorbing the heat of the medium to be cooled and changing from liquid to gas. This process achieves refrigeration of the medium to be cooled.

[0069] The low-temperature absorber 13 can be a device for absorbing the first steam output by the low-temperature evaporator 12 in the semi-cycle refrigeration process, and contains an absorbent. The absorbent stored in the low-temperature absorber 13 (as well as the high-temperature absorber 18, the medium-pressure generator 15, and the high-pressure generator 6) can be a lithium bromide solution, or a multi-salt solution of lithium bromide, such as a lithium bromide-lithium chloride solution ( ), a lithium bromide-sodium chloride solution ( ), a lithium bromide-sodium nitrate solution ( ), a lithium bromide-calcium chloride solution ( ), and the like. After the absorbent in the low-temperature absorber 13 fully contacts the first steam, the absorbent can absorb the first steam to form a dilute solution to be separated (i.e., the dilute solution of the absorbent to be separated), and complete the recovery of the refrigerant.

[0070] The heat exchange assembly can be a device for recovering the waste heat of the solution in the system, and is used to reduce energy loss. Therefore, in the embodiment, the heat exchanger assembly can use the heat of other high-temperature fluid (such as the high-temperature solution output by the pressure generator module) in the system to increase the temperature of the dilute solution to be separated output by the low-temperature absorber 13, and reduce the energy required for the subsequent pressure generator module to heat the dilute solution to be separated. Then, the pressure generator module further heats to generate the high-temperature refrigerant steam to continue participating in the system cycle.

[0071] Therefore, by arranging the low-temperature evaporator 12, the refrigeration of the medium to be cooled is realized by the refrigerant solution output by the condensing assembly, the refrigeration execution process of the semi-cycle is clear, and the refrigeration specificity and efficiency of the semi-cycle are improved. The arrangement of the low-temperature absorber 13 realizes the effective absorption of the first steam, converts it into the dilute solution to be separated, improves the recovery rate of the refrigerant, and reduces the waste of the refrigerant.

[0072] In addition, the heat exchanger assembly can preheat the dilute solution to be separated, reduce the energy consumption required for the pressure generator module to heat the dilute solution to be separated, further improve the energy utilization efficiency of the system, and reduce the overall operating cost.

[0073] In an embodiment of the present application, reference is made to Figure 3 , Figure 3 Figure 3 is a third module block diagram of an intermediate-efficiency absorption refrigeration cycle system according to the present application, as shown, the pressure generator module comprises a high-pressure generator 6 and a low-pressure generator 3 in sequence pipeline communication; the heat exchanger assembly comprises a high-temperature heat exchanger 5 and a low-temperature heat exchanger 2; Figure 3

[0074] The high-pressure generator 6 is connected to the medium-pressure generator 15 and the high-temperature heat exchanger 5, respectively, and the low-pressure generator 3 is connected to the high-temperature heat exchanger 5 and the low-temperature heat exchanger 2, respectively, and the low-temperature heat exchanger 2 is connected to the high-temperature heat exchanger 5 and the low-temperature absorber 13;

[0075] The low-temperature absorber 13 outputs the to-be-fractionated dilute solution, which is preheated by the low-temperature heat exchanger 2 and the high-temperature heat exchanger 5, and then input into the high-pressure generator 6;

[0076] The high-pressure generator 6 is used for heating the preheated to-be-fractionated dilute solution into a high-temperature refrigerant solution and a high-temperature refrigerant vapor based on the heat source, and the high-temperature refrigerant vapor is output to the medium-pressure generator 15 for heating;

[0077] The high-temperature refrigerant solution is input into the low-pressure generator 3 for heating through the high-temperature heat exchanger 5.

[0078] It should be noted that, as shown in Figure 3, the high-pressure generator 6 and the low-pressure generator 3 can be sealed and communicated in sequence to form the main structure of the pressure generator module; the high-temperature heat exchanger 5 and the low-temperature heat exchanger 2 are sealed and connected by pipelines to form the heat exchanger assembly. Figure 3 Meanwhile, the devices of the pressure generator module can be sealed and connected in the order of high-pressure generator 6→ high-temperature heat exchanger 5→ low-pressure generator 3→ low-temperature heat exchanger 2 using stainless steel pipelines; at the same time, the heat exchanger assembly and the low-temperature absorber 13 and the high-pressure generator 6 are sealed and connected in the order of low-temperature absorber 13→ low-temperature heat exchanger 2→ high-temperature heat exchanger 5→ high-pressure generator 6, to ensure that the solution flows in the preset order.

[0079]

[0080] ​​It is easy to understand that the high-pressure generator 6 described above can be a high-temperature heating device in the pressure generator module, receiving the preheated solution to be separated after the heat exchanger assembly, using high-temperature low-grade heat (such as 100-120℃ industrial waste heat) to heat it, so that a large amount of refrigerant in the solution evaporates to generate high-temperature refrigerant vapor and high-temperature refrigerant solution; and the low-pressure generator 3 can be a low-temperature heating device in the pressure generator module, which can receive the high-temperature refrigerant solution from the high-pressure generator 6, and further heat it using low-temperature low-grade heat (such as 60-70℃ industrial waste heat), so that the remaining refrigerant in the solution continues to evaporate to generate low-temperature refrigerant vapor.

[0081] The high-temperature heat exchanger 5 described above can be a high-temperature heat exchange device in the heat exchanger assembly, mainly used to realize heat exchange between the high-temperature refrigerant solution output by the high-pressure generator 6 and the solution to be separated, and transfer the heat of the high-temperature refrigerant solution to the solution to be separated to preheat it; and the low-temperature heat exchanger 2 is a low-temperature heat exchange device in the heat exchanger assembly, used to realize heat exchange between the low-temperature refrigerant solution concentrated solution output by the low-pressure generator 3 and the solution to be separated, and further preheat the solution to be separated, while cooling the low-temperature refrigerant solution concentrated solution.

[0082] As an implementable manner, in the embodiment, the heat source temperature of the low-pressure generator 3 is 60-70℃, and the heat source temperature of the high-pressure generator 6 is 100-120℃.

[0083] It is understood that the heat source temperature (60-70℃) of the low-pressure generator 3 can be the heat source temperature range entering the low-pressure generator 3, which can adapt to medium and low-grade heat (such as industrial waste water waste heat). The heat source temperature (100-120℃) of the high-pressure generator 6 can be the heat source temperature range entering the high-pressure generator 6, which can adapt to higher low-grade heat (such as solar collector hot water).

[0084] Therefore, in the embodiment, the staged cooperation process of the pressure generator module and the heat exchange assembly can be as follows:

[0085] First, the solution to be separated output by the low-temperature absorber 13 can first flow through the low-temperature heat exchanger 2 to absorb the heat of the low-temperature refrigerant solution concentrated solution output by the low-pressure generator 3, and the temperature is preliminarily raised; then flow through the high-temperature heat exchanger 5 to further absorb the heat of the high-temperature refrigerant solution output by the high-pressure generator 6, and the temperature is raised again, completing the preheating process of the solution to be separated.

[0086] Then, the high-pressure generator 6 uses low-grade heat energy (such as high-temperature industrial waste heat) at 100-120℃ to heat the preheated dilute solution to be separated. During the heating process, the refrigerant in the dilute solution to be separated absorbs a large amount of heat and evaporates to form high-temperature refrigerant vapor, which is transported to the medium-pressure generator 15 through the pipeline. At the same time, the refrigerant content in the solution decreases and the concentration increases, becoming a high-temperature refrigerant solution.

[0087] The high-temperature refrigerant solution is transported through a pipeline to the high-temperature heat exchanger 5, where it exchanges heat with the dilute solution to be separated, resulting in a temperature reduction. It is then transported through a pipeline to the low-pressure generator 3, which uses low-grade heat energy (60-70℃) to further heat the high-temperature refrigerant solution. The remaining refrigerant in the solution continues to evaporate, forming low-temperature refrigerant vapor. This low-temperature refrigerant vapor is transported through a pipeline to the condenser assembly. Simultaneously, the solution is further concentrated, forming a concentrated low-temperature refrigerant solution. This concentrated solution is transported through a pipeline to the low-temperature heat exchanger 2, where it exchanges heat with the dilute solution to be separated. It is then transported through a pipeline to the low-temperature absorber 13, completing the solution reflux of the half-effect cycle.

[0088] In this embodiment, the pressure generator module adopts a combination structure of high-pressure generator 6 and low-pressure generator 3, which respectively utilize low-grade heat energy at different temperature levels (100-120℃ and 60-70℃), realize the cascade utilization of low-grade heat energy, improve energy utilization efficiency, and avoid the waste of high-grade heat energy.

[0089] Meanwhile, the heat exchanger assembly adopts a combination structure of high-temperature heat exchanger 5 and low-temperature heat exchanger 2, which preheats the dilute solution to be separated twice, significantly increasing the temperature of the dilute solution to be separated when it enters the high-pressure generator 6, reducing the heating energy consumption of the high-pressure generator 6 and the low-pressure generator 3, and further improving the energy utilization efficiency of the system.

[0090] In addition, the stepwise heating of the high-pressure generator 6 and the low-pressure generator 3 allows the refrigerant in the refrigerant solution to evaporate fully, increasing the production of refrigerant vapor and providing a sufficient energy source for subsequent single-effect and half-effect cycle refrigeration, thereby improving the system's cooling capacity and efficiency.

[0091] In one embodiment of this application, reference is made to Figure 4 , Figure 4 This is a block diagram of the fourth module of an intermediate-efficiency absorption refrigeration cycle system according to this application, as shown below. Figure 4 As shown, the single-effect circulating refrigeration pipeline also includes: an intermediate heat exchanger 16 and a high-temperature absorber 18 that are sequentially connected to the medium-pressure generator 15 via pipelines, and the high-temperature absorber 18 is connected to the low-temperature evaporator 12.

[0092] The intermediate heat exchanger 16 is used to preheat the refrigerant concentrated solution output by the high-temperature absorber 18 and input the preheated refrigerant concentrated solution to the medium-pressure generator 15.

[0093] The medium-pressure generator 15 is used to heat the preheated refrigerant concentrated solution based on the high-temperature refrigerant steam to generate the medium-temperature refrigerant steam, which is transmitted to the high-temperature absorber 18 via the condensing assembly and the low-temperature evaporator 12 to achieve refrigeration of the single-effect cycle refrigeration pipeline.

[0094] It should be noted that, as shown in the embodiment, the single-effect cycle devices can be sealed and connected in the order of the medium-pressure generator 15→the intermediate heat exchanger 16→the high-temperature absorber 18 by using stainless steel pipes, and the high-temperature absorber 18 is connected to the low-temperature evaporator 12 to ensure the orderly flow of the refrigerant solution and steam in the single-effect cycle. Figure 4

[0095] In the embodiment, the high-temperature absorber 18 is a device used to absorb refrigerant steam in the single-effect cycle refrigeration, and also contains an absorbent (such as lithium bromide solution) to complete the recovery of the refrigerant in the single-effect cycle. The refrigerant concentrated solution formed after the absorbent in the high-temperature absorber 18 absorbs the medium-temperature gaseous refrigerant has a high concentration of refrigerant and contains a large amount of refrigerant to be evaporated, which is the core solution to be heated in the single-effect cycle. The intermediate heat exchanger 16 can be a heat recovery device in the single-effect cycle refrigeration, which is used to preheat the refrigerant concentrated solution output by the high-temperature absorber 18, increase the temperature of the refrigerant concentrated solution, reduce the energy required by the medium-pressure generator 15 to heat the refrigerant concentrated solution, and improve the energy utilization efficiency of the single-effect cycle.

[0096] Therefore, in the embodiment, the specific process of the single-effect cycle is as follows:

[0097] 1. The medium-pressure generator 15 receives the heat of the high-temperature refrigerant steam generated by the high-pressure generator 6 and heats the refrigerant concentrated solution preheated by the intermediate heat exchanger 16 to evaporate the refrigerant in the solution to form medium-temperature refrigerant steam.

[0098] 2. The medium-temperature refrigerant steam is condensed into a liquid refrigerant solution by the condensing assembly, and then partially forms steam after passing through the low-temperature evaporator 12 and is transmitted to the high-temperature absorber 18 by the pipeline, which is absorbed by the absorbent in the high-temperature absorber 18 to complete the recovery of the refrigerant in the single-effect cycle.

[0099] As an implementable manner, in an implementable manner, the absorbent concentration of the medium-pressure generator 15 is greater than the absorbent concentration of the high-pressure generator 6.

[0100] ​It can be understood that the concentration of the absorbent refers to the mass percentage of the absorbent (such as lithium bromide) in the solution, and the higher the concentration of the absorbent in the solution, the stronger the ability to absorb the refrigerant vapor.

[0101] The concentration of the absorbent in the high-pressure generator 6 can refer to the concentration of the absorbent (such as lithium bromide solution) in the high-pressure generator 6 for heating to generate high-temperature refrigerant vapor in the semi-cycle. The absorbent in the high-pressure generator 6 comes from the low-temperature absorber 13 and is preheated by the low-temperature heat exchanger 2 and the high-temperature heat exchanger 5 before entering the high-pressure generator 6.

[0102] The concentration of the absorbent in the high-pressure generator 6 can refer to the concentration of the absorbent (such as lithium bromide solution) in the high-pressure generator 6 for heating to generate high-temperature refrigerant vapor in the semi-cycle. The absorbent in the high-pressure generator 6 comes from the low-temperature absorber 13 and is preheated by the low-temperature heat exchanger 2 and the high-temperature heat exchanger 5 before entering the high-pressure generator 6.

[0103] In this embodiment, the concentration of the absorbent (lithium bromide) in the medium-pressure generator 15 can be higher than that in the high-pressure generator 6. For example, the concentration of the lithium bromide solution in the medium-pressure generator 15 can be 55% to 58%, and the concentration of the lithium bromide solution in the high-pressure generator 6 can be 53% to 55%. The high-concentration absorbent in the medium-pressure generator 15 can more efficiently absorb the vapor heat from the high-pressure generator 6, enhancing the solution heating effect. Meanwhile, in the high-temperature absorber 18, the high-concentration absorbent can quickly absorb the refrigerant vapor, improving the reaction rate of the single-cycle.

[0104] It should be noted that the concentration of the absorbent in the medium-pressure generator 15 is higher, and its ability to absorb refrigerant vapor is stronger. After absorbing the medium-temperature gas-phase refrigerant from the gas-liquid separator 10, it can form a refrigerant solution with a higher concentration, providing more sufficient refrigerant to be evaporated for the heating process of the medium-pressure generator 15, improving the refrigerant vapor production of the single-cycle, and further improving the refrigeration efficiency of the single-cycle.

[0105] The relatively low concentration of the absorbent in the high-pressure generator 6 not only matches the heating demand and refrigerant evaporation capacity of the semi-cycle, but also avoids the problems of increased solution viscosity and flow resistance due to too high concentration of the absorbent, and the difficulty of further evaporating the refrigerant due to too high concentration, ensuring smooth operation and efficiency of the semi-cycle.

[0106] Correspondingly, if the absorbent concentration in the medium-pressure generator 15 is not greater than the absorbent concentration in the high-pressure generator 6, it is easy to cause the refrigerant evaporation amount to decrease in the single-effect cycle or the refrigerant absorption to be insufficient in the semi-effect cycle, affecting the overall refrigeration efficiency of the system. Therefore, the embodiment can realize efficient cooperation of the single-effect cycle and the semi-effect cycle by setting the size relationship of the absorbent concentrations in the two generators, so that the two cycles cooperate with each other in energy utilization and refrigerant processing, further improving the coefficient of performance (COP) of the entire system and the energy utilization efficiency, and ensuring that the system can stably and efficiently operate under different working conditions.

[0107] The embodiment first realizes preheating of the refrigerant concentrated solution through the setting of the intermediate heat exchanger 16, reduces the energy consumption required for the medium-pressure generator 15 to heat the refrigerant concentrated solution, and improves the energy utilization efficiency of the single-effect cycle. And through the effective absorption of the refrigerant vapor by the high-temperature absorber 18, the efficient recovery and recycling of the refrigerant in the single-effect cycle are ensured, the loss of the refrigerant is reduced, and the refrigeration efficiency of the single-effect cycle and the stability of the system are further improved. Thus, the single-effect cycle can efficiently utilize the high-temperature refrigerant vapor generated by the semi-effect cycle as a heat source, realizing deep cooperation between the semi-effect cycle and the single-effect cycle, and improving the energy cascade utilization level of the entire system.

[0108] In addition, in view of the problem that the absorbent concentration is uniform in the traditional cycle, which cannot match the heating and absorption requirements of different generators, resulting in limited efficiency, the embodiment can adapt to the requirements of the medium-pressure generator 15 “double heating” (heat source + vapor) and the high-temperature absorber 18 “efficient absorption” with different concentrations, strengthen the energy transfer between the single-effect cycle and the semi-effect cycle, and improve the overall COP.

[0109] In an embodiment of the present application, with reference to Figure 5 , Figure 5 Figure 5 is a fifth module block diagram of an intermediate-effect absorption refrigeration cycle system according to the present application, as shown in the figure, the system further comprises: an intermediate evaporator 9 and a gas-liquid separator 10; Figure 5

[0110] The intermediate evaporator 9 is connected to the gas-liquid separator 10 and the condensing assembly respectively, and the gas-liquid separator 10 is connected to the high-temperature absorber 18 and the low-temperature evaporator 12 respectively;

[0111] The intermediate evaporator 9 is used to cool the medium to be cooled based on the refrigerant solution output by the condensing assembly, generate and output a gas-liquid mixture to the gas-liquid separator 10, and the gas-liquid mixture includes medium-temperature gas-phase refrigerant and low-temperature refrigerant solution;

[0112] ​The gas-liquid separator 10 is configured to transmit the low-temperature refrigeration solution to the low-temperature evaporator 12, so that the low-temperature evaporator 12 performs refrigeration on the medium to be cooled based on the low-temperature refrigeration solution.

[0113] The gas-liquid separator 10 is further configured to transmit the medium-temperature gas-phase refrigerant to the high-temperature absorber 18, and the absorber of the high-temperature absorber 18 absorbs the medium-temperature gas-phase refrigerant to form the refrigerant concentrated solution.

[0114] It should be understood that, as shown in Figure 5 The intermediate evaporator 9, the gas-liquid separator 10, the condensing assembly, the high-temperature absorber 18 and the low-temperature evaporator 12 can be connected by stainless steel pipes, so that the gas-liquid mixture and the separated refrigerant can be smoothly transmitted in the system.

[0115] The intermediate evaporator 9 can be an auxiliary refrigeration device arranged between the condensing assembly and the low-temperature evaporator 12, configured to receive the refrigerant solution from the condensing assembly, perform preliminary refrigeration on the medium to be cooled by using evaporation of the refrigerant solution, and generate a gas-liquid mixture containing the medium-temperature gas-phase refrigerant in a gaseous state and the low-temperature refrigeration solution in a liquid state, to prepare for subsequent gas-liquid separation.

[0116] The gas-liquid separator 10 can be a device for separating the gas-liquid mixture output by the intermediate evaporator 9, configured to separate the medium-temperature gas-phase refrigerant and the low-temperature refrigeration solution in the gas-liquid mixture by gravity sedimentation or centrifugal separation, and transmit the separated low-temperature refrigeration solution to the low-temperature evaporator 12 and the separated medium-temperature gas-phase refrigerant to the high-temperature absorber 18, to realize directional transportation of refrigerants in different states.

[0117] The low-temperature refrigeration solution in the low-temperature evaporator 12 can be further evaporated based on the pre-cooled low-temperature refrigeration solution to absorb heat of the medium to be cooled, so that the temperature of the medium to be cooled is further reduced, and deep refrigeration is realized; the absorber (such as lithium bromide solution) in the high-temperature absorber 18 fully contacts and absorbs the medium-temperature gas-phase refrigerant to form a refrigerant concentrated solution, and the refrigerant concentrated solution is transported to the intermediate heat exchanger 16 by a pipe to participate in the next round of heating process of the single-effect cycle.

[0118] Therefore, the embodiment can further refine the refrigerant processing process by adding the intermediate evaporator 9 and the gas-liquid separator 10, realize staged refrigeration on the medium to be cooled, and improve the refrigeration effect of the system and the utilization efficiency of the refrigerant.

[0119] 1. The arrangement of the intermediate evaporator 9 realizes preliminary refrigeration of the medium to be cooled, shares the refrigeration load of the low-temperature evaporator 12, enables the low-temperature evaporator 12 to focus more on deep refrigeration, and improves the overall refrigeration effect and refrigeration depth of the system.

[0120] 2. The gas-liquid separator 10 effectively separates the medium-temperature gas-phase refrigerant and the low-temperature refrigeration solution in the gas-liquid mixture, so that the low-temperature refrigeration solution with higher subcooling degree after splitting can accurately enter the low-temperature evaporator 12 for deep refrigeration, reducing the evaporation load of the low-temperature evaporator 12 and also reducing the volume requirement of the low-temperature evaporator 12 under the same refrigeration capacity; the medium-temperature gas-phase refrigerant can accurately enter the high-temperature absorber 18 for recovery, i.e., the high-temperature absorber 18 only absorbs pure gas-phase refrigerant, which can avoid dilution of the absorption liquid concentration by liquid-phase refrigerant, maintain high-efficiency absorption power, and reduce heat loss in the absorption process, improving the mass transfer efficiency per unit area.

[0121] In this embodiment, to solve the problems in the existing system that the condensed refrigerant directly enters the evaporator, which can easily lead to low evaporation efficiency due to insufficient superheat degree, and the gas-liquid mixture affects the absorption effect of the absorber, the high-purity gaseous refrigerant is separated by the intermediate evaporator 9 to improve the absorption efficiency of the high-temperature absorber 18; the liquid-phase refrigerant is subcooled and then enters the low-temperature evaporator 12, increasing the evaporation capacity and improving the refrigeration capacity per unit flow, and strengthening the overall refrigeration effect. Meanwhile, the staged refrigeration mode makes the cooling process of the medium to be cooled more stable and efficient, avoids the problem of system instability caused by excessive refrigeration load, and improves the stability and reliability of the system operation.

[0122] In an embodiment of the present application, reference is made to Figure 6 , Figure 6 The present application is a structure schematic diagram of an intermediate-effect absorption refrigeration cycle system, as shown in Figure 6 , the condensing assembly includes a first condenser 7 and a second condenser 20; the refrigerant solution includes a first refrigeration solution and a second refrigeration solution;

[0123] The first condenser 7 is respectively connected to the intermediate-pressure generator 15 and the intermediate evaporator 9, and the second condenser 20 is respectively connected to the low-pressure generator 3 and the intermediate evaporator 9;

[0124] The first condenser 7 is used for condensing the medium-temperature refrigerant vapor output by the intermediate-pressure generator 15 after heating into the first refrigeration solution, and outputting the first refrigeration solution to the intermediate evaporator 9;

[0125] The second condenser 20 is used for condensing the low-temperature refrigerant vapor output by the low-pressure generator 3 after heating into the second refrigeration solution, and outputting the second refrigeration solution to the intermediate evaporator 9.

[0126] It should be noted that, as Figure 6 As shown, in this embodiment, stainless steel pipes can be used to seal the inlet of the first condenser 7 to the steam outlet of the medium-pressure generator 15, and the outlet to the inlet of the intermediate evaporator 9; and the inlet of the second condenser 20 to the steam outlet of the low-pressure generator 3, and the outlet to the inlet of the intermediate evaporator 9, to ensure that refrigerant vapors from different sources can enter the corresponding condensers, and the condensed solution can enter the intermediate evaporator 9.

[0127] The first condenser 7 can be a high-temperature condensing device in the condensing assembly, specifically used to cool and condense the medium-temperature refrigerant vapor output from the medium-pressure generator 15, converting it into a liquid first refrigeration solution. It is the core device for refrigerant condensation in a single-effect cycle. The second condenser 20 can be a low-temperature condensing device in the condensing assembly, used to cool and condense the low-temperature refrigerant vapor output from the low-pressure generator 3, converting it into a liquid second refrigeration solution. It is an important device for refrigerant condensation in a half-effect cycle.

[0128] In this embodiment, a cooling medium (such as cooling water) is introduced into the condensation components (first condenser 7 and second condenser 20). The cooling medium exchanges heat with the refrigerant vapor, causing the refrigerant vapor to release heat, lower its temperature, and change from a gaseous state to a liquid state, forming corresponding refrigerant solutions (i.e., the first refrigerant solution and the second refrigerant solution). The first condenser 7 transports the condensed, medium-temperature first refrigerant solution to the intermediate evaporator 9 through a pipeline, and the second condenser 20 can also transport the condensed, low-temperature second refrigerant solution to the intermediate evaporator 9 through a pipeline, providing sufficient refrigerant solution for the intermediate evaporator 9.

[0129] It is easy to understand that traditional condensing units are mostly single devices that simultaneously process refrigerant vapors at different temperatures. This leads to insufficient condensation of high-temperature vapors or overcooling of low-temperature vapors, wasting energy and affecting system efficiency. Therefore, to solve the problem of low condensation efficiency and insufficient condensation of refrigerant vapors at different temperatures in condensing units, in this embodiment, the condensing unit can adopt a split structure of a first condenser 7 and a second condenser 20, which respectively process medium-temperature refrigerant vapors and low-temperature refrigerant solutions. This ensures that each refrigerant can be fully condensed under suitable temperature conditions, improving condensation efficiency and sufficiency, and avoiding waste of refrigerant vapors. At the same time, the split condensing structure allows for more rational use of the cooling medium, avoiding energy waste of the cooling medium caused by processing vapors at different temperatures, reducing the system's cooling energy consumption, and improving the overall energy utilization efficiency of the system.

[0130] In one embodiment, the system further includes a first solution pump 1; the first solution pump 1 is connected to the low-temperature absorber 13 and the low-temperature heat exchanger 2 respectively;

[0131] The first solution pump 1 is used to transport the dilute solution to be separated generated by the low-temperature absorber 13 to the low-temperature heat exchanger 2.

[0132] It should be understood that, as shown in the figure, the first solution pump 1 can be connected to the dilute solution outlet of the low-temperature absorber 13 and the dilute solution inlet of the low-temperature heat exchanger 2 by using corrosion-resistant pipes (such as PTFE pipes or stainless steel pipes) to form a dilute solution conveying path. Figure 6 The first solution pump 1 is a power device for conveying the dilute solution to be separated in the semi-effective cycle, has corrosion resistance and high-temperature resistance, and can suck the dilute solution to be separated in the low-temperature absorber 13 into the pump body by mechanical power (such as motor-driven impeller rotation to generate pressure), and then convey the dilute solution to be separated to the low-temperature heat exchanger 2 under the action of pressure to realize the directional movement of the dilute solution to be separated, and is a power source for the solution flow in the semi-effective cycle.

[0133] In an implementation manner, the system further comprises a second solution pump 19; the second solution pump 19 is connected to the high-temperature absorber 18 and the intermediate heat exchanger 16 respectively.

[0134] The first solution pump 1 is used to transport the dilute solution to be separated generated by the low-temperature absorber 13 to the low-temperature heat exchanger 2.

[0135] It should be understood that, as shown in the figure, the first solution pump 1 can be connected to the dilute solution outlet of the low-temperature absorber 13 and the dilute solution inlet of the low-temperature heat exchanger 2 by using corrosion-resistant pipes (such as PTFE pipes or stainless steel pipes) to form a dilute solution conveying path.

[0136] Further, the second solution pump 19 can suck the concentrated refrigerant solution in the high-temperature absorber 18 into the pump body by the pressure generated by the motor-driven impeller rotation, and then convey the concentrated refrigerant solution to the intermediate heat exchanger 16 under the action of pressure to realize the directional conveying of the concentrated refrigerant solution.

[0137]

[0138] ​In addition, the first solution pump 1 or the second solution pump 19 can adjust the delivery flow and pressure according to the operation requirements of the system, so that the delivery amount of the dilute solution to be separated or the concentrated solution of the refrigerant matches the requirements of the subsequent preheating and heating process, further optimizes the operation parameters of the semi-efficient cycle, and improves the energy utilization efficiency and refrigeration efficiency of the refrigeration cycle.

[0139] It is easy to understand that in the existing semi-efficient cycle and single-efficient cycle, the dilute solution to be separated relies on gravity flow. When the system pipeline is long or there is resistance, the flow speed is slow or even unable to flow, which causes the semi-efficient cycle and single-efficient cycle to be interrupted or reduced in efficiency. To solve this problem, the first solution pump 1 is provided for the flow of the dilute solution to be separated, and the second solution pump 19 is provided for the flow of the concentrated solution of the refrigerant, so as to provide stable power for the flow of the dilute solution to be separated and the concentrated solution of the refrigerant, to ensure that the dilute solution to be separated and the concentrated solution of the refrigerant can overcome the resistance of the system pipeline and be quickly and stably delivered, to ensure smooth operation of the refrigeration cycle and avoid the problem of reduced efficiency or interruption of the system caused by poor solution flow.

[0140] In an implementable manner, as shown in Figure 6 The system further comprises a first flow regulating valve 4, a second flow regulating valve 8, a third flow regulating valve 11, a fourth flow regulating valve 14, and a fifth flow regulating valve 17.

[0141] The first flow regulating valve 4 is connected to the high-temperature heat exchanger 5 and the low-pressure generator 3, the second flow regulating valve 8 is connected to the first condenser 7 and the intermediate evaporator 9, the third flow regulating valve 11 is connected to the gas-liquid separator 10 and the low-temperature evaporator 12, the fourth flow regulating valve 14 is connected to the low-temperature heat exchanger 2 and the low-temperature absorber 13, and the fifth flow regulating valve 17 is connected to the high-temperature absorber 18 and the intermediate heat exchanger 16.

[0142] It should be noted that the basic function of the first flow regulating valve 4, the second flow regulating valve 8, the third flow regulating valve 11, the fourth flow regulating valve 14, and the fifth flow regulating valve 17 is to regulate the pressure, so that the absorbers (i.e., the low-temperature absorber 13 and the high-temperature absorber 18) and the evaporators (i.e., the intermediate evaporator 9 and the low-temperature evaporator 12) are maintained in a stable and safe operating range through pressure reduction by throttling; at the same time, each flow regulating valve also has corresponding flow regulating capability, so that the unit can be adjusted according to the system load fluctuation under variable load conditions.

[0143] In summary, in the intermediate-efficiency absorption refrigeration cycle system provided by the application, the heat source input end of the system is directly connected to a low-grade heat supply device (such as an industrial waste heat pipeline, a geothermal water pump or a solar heat collector), the heat source first enters the high-pressure generator 6 of the semi-efficient cycle (utilizing 100-120℃ energy) for primary high-temperature driving, then enters the medium-pressure generator 15 of the single-effect cycle (utilizing lower-temperature energy) for secondary energy reuse, and the remaining heat enters the low-pressure generator 3 (utilizing 60-70℃ energy) for tertiary deep recovery, realizing full-process non-dependence on high-temperature heat sources, so that the external driving heat required by the application is far less than that of the traditional cycle under the premise of obtaining the same refrigeration capacity. The high-temperature absorber 18 serves as the coupling node of the circulation process of the first refrigerant solution and the circulation process of the second refrigerant solution, can not only absorb the gaseous refrigerant (from the gas-liquid separator 10) generated by the circulation of the first refrigerant solution, but also provide the second refrigerant solution circulation with low-concentration solution to be regenerated, so as to convert the waste heat of the first refrigerant solution circulation into the driving force of the second refrigerant solution circulation, realize the thermal energy cascade reuse of the two sets of cycles, reduce the irreversible loss of the low-temperature evaporator 12, and reduce the energy consumption of the medium-pressure generator 15 through the independent solution regeneration cycle (i.e., the independent closed loop formed by the high-temperature absorber 18→ the second solution pump 19→ the medium-pressure generator 15→ the intermediate heat exchanger 16→ the high-temperature absorber 18).

[0144] Secondly, in the traditional cycle, the condensed refrigerant is directly throttled and evaporated, and its cold energy potential has not been fully tapped. The application first performs preliminary refrigeration through the intermediate evaporator 9, and then separates the preliminary gas-liquid mixture into high-grade energy (i.e., medium-temperature gaseous refrigerant) and low-grade working medium (i.e., low-temperature refrigeration solution in liquid phase) through the core component, the gas-liquid separator 10. Then, the medium-temperature gaseous refrigerant is delivered to the high-temperature absorber 18 according to the demand, and its grade is just matched with the demand of the absorption process, efficiently driving the single-effect sub-cycle. The low-temperature refrigeration solution in liquid phase becomes supercooled liquid due to flashing, so that the unit refrigeration capacity in the low-temperature evaporator 12 is greatly improved, and the molecules (refrigeration capacity) are significantly increased.

[0145] Therefore, the application can directly utilize low-grade heat to drive refrigeration, widen the energy utilization range, realize a 30%-40% COP improvement of the system, reduce the consumption of fossil energy and the emission of greenhouse gases, and achieve a win-win of energy saving and environmental protection. That is, the application focuses on the core of "high-efficiency utilization of low-grade heat", realizes the high-efficiency utilization of low-grade heat through the coupling of semi-efficient and single-effect cycles, the cascade utilization of multi-stage pressure heat sources and the dual-cycle refrigerant coupling of component collaborative design, takes the concentration difference of the absorbent solution as the medium, breaks through the temperature and energy efficiency limitations of the traditional absorption refrigeration system, solves the problems of low efficiency and poor heat source adaptability of the traditional cycle, and realizes the dual effects of refrigeration efficiency improvement and low-grade heat recovery.

[0146] The above merely preferred embodiments of the present application, and not therefore limit the patent scope of the present application, any equivalent structural transformation made in the concept of the present application, using the contents of the present application specification and drawings, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present application.

Claims

1. An intermediate-effect absorption refrigeration cycle system, comprising: The system comprises a semi-cycle refrigeration pipeline and a single-cycle refrigeration pipeline; The semi-cycle refrigeration pipeline is provided with a pressure generator module and a condensing assembly, and the single-cycle refrigeration pipeline is provided with a medium-pressure generator; The pressure generator module is connected with the medium-pressure generator, the medium-pressure generator is connected with the condensing assembly, and the condensing assembly is connected with the pressure generator module; The pressure generator module is used for heating refrigerant solution output by the condensing assembly under the driving of a heat source, generating high-temperature refrigerant vapor, transmitting the high-temperature refrigerant vapor to the medium-pressure generator to drive refrigeration of the single-cycle refrigeration pipeline, and transmitting medium-temperature refrigerant vapor generated by the medium-pressure generator to the condensing assembly; The semi-cycle refrigeration pipeline further comprises a low-temperature evaporator and a low-temperature absorber which are sequentially connected with the condensing assembly in sequence according to pipelines, and a heat exchanger assembly which is connected with the low-temperature absorber according to a pipeline and is connected with the pressure generator module; The low-temperature evaporator is used for refrigerating a medium to be cooled based on the refrigerant solution output by the condensing assembly, so as to convert the refrigerant solution into a first vapor; The low-temperature absorber is used for absorbing the first vapor based on an absorbent, generating a dilute solution to be separated, preheating the dilute solution to be separated through the heat exchanger assembly, and inputting the preheated dilute solution to be separated into the pressure generator module for heating; The pressure generator module comprises a high-pressure generator and a low-pressure generator which are sequentially connected according to pipelines; and the heat exchanger assembly comprises a high-temperature heat exchanger and a low-temperature heat exchanger; The high-pressure generator is connected with the medium-pressure generator and the high-temperature heat exchanger respectively, the low-pressure generator is connected with the high-temperature heat exchanger and the low-temperature heat exchanger respectively, and the low-temperature heat exchanger is connected with the high-temperature heat exchanger and the low-temperature absorber; The low-temperature absorber outputs the preheated dilute solution to be separated through the low-temperature heat exchanger and the high-temperature heat exchanger and inputs the preheated dilute solution to be separated into the high-pressure generator; The high-pressure generator is used for heating the preheated dilute solution to be separated into high-temperature refrigerant solution and high-temperature refrigerant vapor based on the heat source, and the high-temperature refrigerant vapor is output to the medium-pressure generator for heating; The high-temperature refrigerant solution is input to the low-pressure generator for heating through the high-temperature heat exchanger.

2. The intermediate-effect absorption refrigeration cycle system of claim 1, wherein, The single-cycle refrigeration pipeline further comprises an intermediate heat exchanger and a high-temperature absorber which are sequentially connected with the medium-pressure generator according to pipelines, and the high-temperature absorber is connected with the low-temperature evaporator; The intermediate heat exchanger is used for preheating refrigerant concentrated solution output by the high-temperature absorber and inputting the preheated refrigerant concentrated solution into the medium-pressure generator; The medium-pressure generator is used for heating the preheated refrigerant concentrated solution based on the high-temperature refrigerant vapor, generating the medium-temperature refrigerant vapor, and transmitting the medium-temperature refrigerant vapor to the high-temperature absorber via the condensing assembly and the low-temperature evaporator to realize refrigeration of the single-cycle refrigeration pipeline.

3. The intermediate-effect absorption refrigeration cycle system of claim 2, wherein, The system further comprises an intermediate evaporator and a gas-liquid separator; The intermediate evaporator is connected with the gas-liquid separator and the condensing assembly respectively, and the gas-liquid separator is connected with the high-temperature absorber and the low-temperature evaporator respectively; The intermediate evaporator is configured to cool the medium to be cooled based on the refrigerant solution output by the condensing assembly, to generate and output a gas-liquid mixture to the gas-liquid separator, the gas-liquid mixture comprising medium-temperature gas-phase refrigerant and low-temperature refrigerant solution; The gas-liquid separator is configured to transmit the low-temperature refrigerant solution to the low-temperature evaporator, so that the low-temperature evaporator cools the medium to be cooled based on the low-temperature refrigerant solution; The gas-liquid separator is further configured to transmit the medium-temperature gas-phase refrigerant to the high-temperature absorber, and the absorbent in the high-temperature absorber absorbs the medium-temperature gas-phase refrigerant to form the refrigerant concentrated solution.

4. The intermediate-effect absorption refrigeration cycle system of claim 3, wherein, The condensing assembly comprises a first condenser and a second condenser, and the refrigerant solution comprises a first refrigerant solution and a second refrigerant solution; The first condenser is connected with the medium-pressure generator and the intermediate evaporator respectively, and the second condenser is connected with the low-pressure generator and the intermediate evaporator respectively; The first condenser is configured to condense the medium-temperature refrigerant vapor output by the medium-pressure generator after heating into the first refrigerant solution, and output the first refrigerant solution to the intermediate evaporator; The second condenser is configured to condense the low-temperature refrigerant vapor output by the low-pressure generator after heating into the second refrigerant solution, and output the second refrigerant solution to the intermediate evaporator.

5. The intermediate-effect absorption refrigeration cycle system of claim 4, wherein, The system further comprises a first solution pump; the first solution pump is connected with the low-temperature absorber and the low-temperature heat exchanger respectively; The first solution pump is configured to transmit the dilute solution to be separated generated by the low-temperature absorber to the low-temperature heat exchanger.

6. The intermediate-effect absorption refrigeration cycle system of claim 5, wherein, The system further comprises a second solution pump; the second solution pump is connected with the high-temperature absorber and the intermediate heat exchanger respectively; The second solution pump is configured to transmit the refrigerant concentrated solution generated by the high-temperature absorber to the intermediate heat exchanger.

7. The intermediate-effect absorption refrigeration cycle system of claim 1, wherein, The heat source is low-grade heat energy, including at least one of industrial waste heat, geothermal energy, and solar energy.

8. The intermediate-effect absorption refrigeration cycle system of claim 1, wherein, The absorbent concentration of the medium-pressure generator is greater than the absorbent concentration of the high-pressure generator.

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