A lithium bromide absorption unit capable of double-effect refrigeration and single-effect heating

Abstract

The utility model relates to a lithium bromide absorption unit of double-effect refrigeration and single-effect heating, which is based on a steam double-effect lithium bromide absorption water chiller with solution parallel circulation, a heat pump generator is additionally arranged in the low-pressure generator and the condenser cylinder, the heat pump generator is arranged between the low-pressure generator and the condenser, a condensate heat exchanger for the heat pump is separately arranged, and switching and adjusting valves are additionally arranged between the pipelines connecting the components. Through the switching and adjusting of the valves, the double-effect refrigeration cycle and the single-effect heating cycle can be safely, stably and reliably operated on the same unit, the initial investment of the equipment is reduced, the management cost of the equipment is saved, the land occupation of the equipment is saved, the annual operation rate of the unit is improved, the unit has wider adaptability and can be designed in a large size. The unit can meet the air conditioning and production process use through double-effect refrigeration in summer and can recover waste heat for heating through single-effect heat pump in winter, is very energy-saving and environment-friendly, and has very good economic and social benefits.

Description

Technical Field

[0001] This utility model relates to the field of refrigeration equipment technology, specifically to a lithium bromide absorption chiller capable of both dual-effect refrigeration and single-effect heating. Background Technology

[0002] In production processes and daily life, cooling is typically needed in summer and heating in winter. In situations with steam heat sources and low-temperature waste heat, for energy conservation and environmental protection, summer cooling requires the installation of steam-powered dual-effect lithium bromide absorption chillers (such as...). Figure 1 The diagram shown illustrates the working principle of one type of parallel circulation process in a steam-type double-effect lithium bromide absorption chiller. Winter heating requires the installation of a Class I lithium bromide absorption heat pump unit (such as...). Figure 2 The diagram shown illustrates the working principle of one type of single-effect cycle process in a first-class lithium bromide absorption heat pump unit. Simultaneous construction of both types of equipment inevitably increases initial investment and management costs. To reduce initial investment, lower operating costs, and minimize equipment footprint, it is necessary to research and develop highly efficient lithium bromide absorption heat pump units that are adaptable, energy-saving, easy to operate, safe, reliable, and capable of providing both cooling in summer and heating in winter. Utility Model Content

[0003] The purpose of this utility model is to provide a lithium bromide absorption chiller that is widely adaptable, energy-saving, easy to operate, safe and reliable, with both dual-effect refrigeration and single-effect heating. It has a high annual utilization rate and can reduce initial investment and management costs as well as floor space.

[0004] The purpose of this utility model is achieved as follows: A lithium bromide absorption chiller capable of both dual-effect refrigeration and single-effect heating comprises a high-pressure generator, a low-pressure generator, a condenser, an evaporator, an absorber, a high-temperature heat exchanger, a low-temperature heat exchanger, a condensate heat exchanger for refrigeration, a high-pressure dilute solution pump, a low-pressure dilute solution pump, and a refrigerant pump, forming a steam dual-effect lithium bromide absorption chiller with parallel solution circulation. A heat pump generator is also installed within the cylinder containing the low-pressure generator and the condenser, positioned between them. The heat pump generator and the condenser are separated by a baffle plate assembly. The low-pressure generator and the heat pump generator share a concentrated solution bladder and concentrated solution piping. The heat pump generator is equipped with a separate condensate heat exchanger for heat pumps. Hot water enters the condensate heat exchanger for heat pumps through a hot water inlet pipe. A hot water switching valve D is provided on the hot water inlet pipe for heat pumps. A dilute solution connecting pipe is provided between the pipelines at the outlets of the high-pressure dilute solution pump and the low-pressure dilute solution pump. A dilute solution switching valve A is provided on the dilute solution connecting pipe. A dilute solution switching valve B is provided on the dilute solution pipeline before entering the high-temperature heat exchanger. The dilute solution pipeline from the condensate heat exchanger for refrigeration is divided into two branches: one is the inlet pipe of the low-pressure generator, which is equipped with a dilute solution switching valve E; the other is the inlet pipe of the heat pump generator, which is equipped with a dilute solution switching valve F. A refrigerant water regulating valve G is installed on the refrigerant water U-shaped pipe from the condenser to the evaporator; A cooling water switching valve H is installed on the cooling water pipe leading to the condenser, a cooling water switching valve I is installed on the cooling water pipe leading to the absorber, and a hot water switching valve J is installed on the hot water pipes leading to the absorber and the condenser.

[0005] Preferably, in summer, when the unit operates in a dual-effect refrigeration mode according to the parallel circulation process of the solution, the electric regulating valve for steam, dilute solution switching valve A, hot water switching valve D, dilute solution switching valve F and hot water switching valve J of the heat pump are closed, and the heat pump generator and the condensate heat exchanger for the heat pump stop operating; the electric regulating valve for steam, dilute solution switching valve B, dilute solution switching valve E, refrigerant water regulating valve G, cooling water switching valve H and cooling water switching valve I of the refrigeration are opened, and the opening degree of the high-temperature refrigerant water throttling valve K is adjusted according to the refrigeration operation requirements.

[0006] Preferably, in winter, when the unit operates in heating mode according to the single-effect heating cycle, the following valves are closed: the electric regulating valve for refrigeration steam, the dilute solution switching valve B, the dilute solution switching valve E, the cooling water switching valve H, the cooling water switching valve I, and the high-temperature refrigerant water throttling valve K. The high-pressure generator, the low-pressure generator, the high-temperature heat exchanger, and the refrigeration condensate heat exchanger stop operating. The following valves are opened: the electric regulating valve for heat pump steam, the dilute solution switching valve A, the hot water switching valve D, the dilute solution switching valve F, and the hot water switching valve J. The opening of the refrigerant water regulating valve G is adjusted according to the operating status of the heat pump.

[0007] The beneficial effects of this utility model are: Through the aforementioned novel structural design and valve switching and adjustment, both the dual-effect refrigeration cycle and the single-effect heating cycle can operate safely, stably, and reliably on the same unit, achieving dual functionality with a single machine. This reduces initial equipment investment, saves equipment management costs, conserves space, and increases the unit's annual operating utilization rate. When designing the unit, the area of ​​the chiller can be determined first based on the external parameters for refrigeration and heating, as well as the required load size. Then, the area of ​​the heat pump generator can be determined based on the area of ​​the evaporator absorber required for refrigeration, while the condenser area can be determined to accommodate both refrigeration and heating needs. Alternatively, the area of ​​the heat pump unit can be determined first, and then the areas of the high-pressure and low-pressure generators can be determined based on the area of ​​the evaporator absorber required for heating. This allows the unit's refrigeration and heating loads to be matched to user needs, reducing material costs. The added heat pump generator eliminates the limitations of the area and structure of the high-pressure generator used for refrigeration, allowing for targeted design based on external steam conditions. For example, heat pumps are applicable to steam pressures between 0.8 MPa.G and 0.1 MPa.G, broadening the unit's adaptability. Larger-scale designs are also possible based on user requirements. Therefore, the unit of this utility model can provide dual-effect cooling in summer to meet the needs of air conditioning and production processes, and a single-effect heat pump in winter to recover waste heat for heating. It is very energy-saving and environmentally friendly, and has very good economic and social benefits. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the working principle of one type of solution parallel circulation process in a steam-type double-effect lithium bromide absorption chiller.

[0009] Figure 2 This is a schematic diagram of the working principle of one type of single-effect cycle process in a Class I lithium bromide absorption heat pump unit.

[0010] Figure 3 This utility model discloses a flow chart of a lithium bromide absorption chiller capable of both dual-effect refrigeration and single-effect heating.

[0011] In the diagram: 1. High-pressure generator; 2. Low-pressure generator; 3. Condenser; 4. Cooling water outlet or hot water outlet; 5. Cold water outlet or waste hot water outlet; 6. Evaporator; 7. Absorber; 8. Cold water inlet or waste hot water inlet; 9. Cooling water inlet or hot water inlet; 10. Refrigerant pump; 11. High-pressure dilute solution pump; 12. Low-pressure dilute solution pump; 13. Low-temperature heat exchanger; 14. Condensate heat exchanger for refrigeration; 15. Condensate outlet; 16. High-temperature heat exchanger; 17. Refrigeration steam inlet; 18. Electric regulating valve for refrigeration steam. 8. High-temperature refrigerant water throttling valve K19. Heat pump generator 20. Hot water switching valve D21. Heat pump condensate heat exchanger 22. Heat pump condensate outlet 23. Heat pump steam inlet 24. Heat pump steam inlet regulating valve 25. Dilute solution switching valve E26. Dilute solution switching valve F27. Cooling water switching valve I28. Hot water switching valve J29. Refrigerant water regulating valve G30. Cooling water switching valve H31. Dilute solution switching valve A32. Dilute solution switching valve B33. Detailed Implementation

[0012] See Figure 3 This utility model relates to a lithium bromide absorption chiller capable of both dual-effect refrigeration and single-effect heating, comprising a high-pressure generator 1, a low-pressure generator 2, a heat pump generator 20, a condenser 3, an evaporator 6, an absorber 7, a high-temperature heat exchanger 16, a low-temperature heat exchanger 13, a condensate heat exchanger 14 for refrigeration, a condensate heat exchanger 22 for heat pump, a high-pressure dilute solution pump 11, a low-pressure dilute solution pump 12, a refrigerant pump 10, and connecting pipes, valves, and a control system between the components, in which the solution circulates in parallel. Based on the steam-type double-effect lithium bromide absorption chiller unit, a heat pump generator 20 is added inside the low-pressure generator 2 and condenser 3 cylinders, and the heat pump generator 20 is placed between the low-pressure generator 2 and condenser 3. The heat pump generator 20 includes a heat pump generator heat transfer tube bundle, a heat pump generator liquid inlet pipe, a heat pump generator solution distribution pipe, a heat pump generator spray plate, and front and rear pipe boxes of the heat pump generator. The concentrated solution bladder and concentrated solution pipeline of the heat pump generator are shared with the concentrated solution bladder and concentrated solution pipeline of the low-pressure generator.

[0013] The heat pump generator 20 is equipped with a separate condensate heat exchanger 22 for the heat pump. A hot water inlet to the condensate heat exchanger is provided from the hot water inlet, and a hot water switching valve D21 is installed on this pipeline.

[0014] A dilute solution connecting pipe is provided between the outlets of the high-pressure dilute solution pump 11 and the low-pressure dilute solution pump 12, and a dilute solution switching valve A32 is installed on it. A dilute solution switching valve B33 is installed on the dilute solution pipeline before entering the high-temperature heat exchanger. The dilute solution pipeline exiting the condensate heat exchanger 14 for refrigeration is divided into two branches: one is the inlet pipe of the low-pressure generator, which is equipped with a dilute solution switching valve E26; the other is the inlet pipe of the heat pump generator, which is equipped with a dilute solution switching valve F27.

[0015] A refrigerant water regulating valve G30 is installed on the refrigerant water U-shaped pipe from the condenser to the evaporator.

[0016] A cooling water switching valve H31 is installed on the cooling water pipe leading to the condenser, a cooling water switching valve I28 is installed on the cooling water pipe leading to the absorber, and a hot water switching valve J29 is installed on the hot water pipes leading to the absorber and the condenser.

[0017] In summer, when the unit operates in dual-effect refrigeration mode according to the parallel circulation process of the solution, close the following five valves: heat pump steam electric regulating valve 25, dilute solution switching valve A32, hot water switching valve D21, dilute solution switching valve F27, and hot water switching valve J29. The heat pump generator 20 and the heat pump condensate heat exchanger 22 will stop operating. Open the following six valves: refrigeration steam electric regulating valve 18, dilute solution switching valve B33, dilute solution switching valve E26, refrigerant water regulating valve G30, cooling water switching valve H31, and cooling water switching valve I28. Adjust the opening degree of the high-temperature refrigerant water throttling valve K according to the refrigeration operation requirements. The dual-effect refrigeration process is as follows: High-pressure dilute solution pump 11 lifts a portion of the dilute solution, heats it via high-temperature heat exchanger 16, and enters the high-pressure generator 1 housing. Driven steam within the high-pressure generator tube bundle concentrates the dilute solution into a high-pressure concentrated solution, simultaneously generating high-temperature refrigerant vapor. The high-pressure concentrated solution is cooled by high-temperature heat exchanger 16 and flows by gravity into the absorber 7 spray plate. The high-temperature refrigerant vapor enters the low-pressure generator 2 tube bundle, releasing heat and condensing into high-temperature refrigerant water. Low-pressure dilute solution pump 12 lifts a portion of the dilute solution, first through low-temperature heat exchanger 13, then through refrigeration condensate heat exchanger 14, and heats it before entering the low-pressure generator 2 spray plate. It is sprayed onto the surface of the low-pressure generator 2 tube bundle, absorbing heat and concentrating into a low-pressure concentrated solution, simultaneously generating low-temperature refrigerant vapor. The low-pressure concentrated solution is cooled by the low-temperature heat exchanger 13 and flows by gravity into the absorber 7's spray plate. The low-temperature refrigerant vapor passes through the heat pump generator tubes and enters the condenser 3 through the liquid-blocking device, releasing heat and condensing into refrigerant water. The high-temperature refrigerant water is throttled by the high-temperature refrigerant water throttling valve K19 and enters the bottom of the condenser 3. After flashing, it flows by gravity together with the refrigerant water condensed in the condenser 3 and enters the evaporator 6 through the refrigerant water regulating valve G30 on the refrigerant water U-tube. The unflashed refrigerant water enters the bottom of the evaporator 6 and is pumped into the surface of the evaporator 6 tube bundle by the refrigerant pump 10 to absorb heat and evaporate. The evaporated refrigerant vapor enters the absorber 7 and is absorbed by the concentrated solution sprayed on the surface of the absorber 7 tube bundle inside the absorber's spray plate, becoming a dilute solution that enters the bottom of the absorber 7. The driving steam supplied by the external system enters the high-pressure generator 1 through the electric regulating valve 18 for refrigeration steam, where it releases heat and condenses into condensate. The condensate is cooled by the refrigeration condensate heat exchanger 14 and then flows out of the unit from the condensate outlet 15. Chilled water enters the evaporator 6 through the chilled water inlet 8, where it releases heat and cools before flowing out of the unit from the chilled water outlet 5. Cooling water enters the absorber 7 and condenser 3 in parallel through the cooling water inlet 9, where it absorbs heat and heats up before flowing out of the unit from the cooling water outlet 4. The unit continuously circulates this process to produce chilled water for user use.

[0018] In winter, when the unit operates in heating mode according to the single-effect heating cycle, close the following six valves: refrigeration steam electric regulating valve 18, dilute solution switching valve B33, dilute solution switching valve E26, cooling water switching valve H31, cooling water switching valve I28, and high-temperature refrigerant water throttling valve K19. The high-pressure generator 1, low-pressure generator 2, high-temperature heat exchanger 16, and refrigeration condensate heat exchanger 14 will stop operating. Open the following five valves: heat pump steam inlet regulating valve 25, dilute solution switching valve A32, hot water switching valve D21, dilute solution switching valve F27, and hot water switching valve J29. Adjust the opening of the refrigerant water regulating valve G30 according to the operating status of the heat pump. The single-effect heating process is as follows: High-pressure dilute solution pump 11 and low-pressure dilute solution pump 12 are connected in parallel to simultaneously lift the dilute solution. The dilute solution is heated by low-temperature heat exchanger 13 and flows through refrigeration condensate heat exchanger 14 into the liquid distribution pipe of heat pump generator 20 and then into the spray plate of heat pump generator 20. The dilute solution is sprayed on the surface of heat pump generator 20 tube bundle and the heat of the driving steam in the absorption tube becomes a concentrated solution. The concentrated solution is cooled by low-temperature heat exchanger 13 and flows by gravity into the spray plate of absorber 7. The refrigerant vapor generated by the concentrated solution of heat pump generator 20 enters condenser 3 through liquid baffle device, releases heat and condenses into refrigerant water. The refrigerant water is throttled by refrigerant water regulating valve G30 and enters evaporator 6 for flashing. The unflashed refrigerant water enters the bottom of evaporator 6 and is pumped into the surface of evaporator 6 tube bundle by refrigerant pump 10 to absorb heat and evaporate. The evaporated refrigerant vapor enters absorber 7 and is absorbed by the concentrated solution sprayed on the surface of absorber 7 tube bundle in absorber spray plate, becoming a dilute solution that enters the bottom of absorber 7. The driving steam supplied by the external system enters the high-pressure generator 1 through the heat pump's electric steam regulating valve 25, releasing heat and condensing into condensate. The condensate is then cooled by the heat pump's condensate heat exchanger 22, which heats the hot water in the tubes, before flowing out of the unit from the heat pump condensate outlet 23. Waste hot water enters the evaporator 6 through the waste hot water inlet 8, releasing heat and cooling before flowing out of the unit from the waste hot water outlet 5. Hot water from the hot water inlet 9 splits into two paths: one enters the absorber 7 to absorb heat and increase its temperature, and the other enters the heat pump's condensate heat exchanger 22 to absorb heat and increase its temperature. The hot water then merges and enters the condenser 3 through the tubes to absorb heat and further increase its temperature before flowing out of the unit from the hot water outlet 4. The unit continuously cycles in this way, recovering heat from the waste hot water to produce hot water for users.

[0019] In addition to the above embodiments, this utility model also includes other implementation methods. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of this utility model.

Claims

1. A lithium bromide absorption chiller capable of both dual-effect refrigeration and single-effect heating, comprising a high-pressure generator, a low-pressure generator, a condenser, an evaporator, an absorber, a high-temperature heat exchanger, a low-temperature heat exchanger, a condensate heat exchanger for refrigeration, a high-pressure dilute solution pump, a low-pressure dilute solution pump, and a refrigerant pump, forming a parallel-circulation steam dual-effect lithium bromide absorption chiller, characterized in that: A heat pump generator is also installed inside the cylinder containing the low-pressure generator and the condenser. The heat pump generator is placed between the low-pressure generator and the condenser. The heat pump generator and the condenser are separated by a baffle plate assembly. The low-pressure generator and the heat pump generator share a concentrated solution bladder and a concentrated solution pipeline. The heat pump generator is equipped with a separate condensate heat exchanger for heat pumps. Hot water enters the condensate heat exchanger for heat pumps through a hot water inlet pipe. A hot water switching valve D is provided on the hot water inlet pipe for heat pumps. A dilute solution connecting pipe is provided between the pipelines at the outlets of the high-pressure dilute solution pump and the low-pressure dilute solution pump. A dilute solution switching valve A is provided on the dilute solution connecting pipe. A dilute solution switching valve B is provided on the dilute solution pipeline before entering the high-temperature heat exchanger. The dilute solution pipeline from the condensate heat exchanger for refrigeration is divided into two branches: one is the inlet pipe of the low-pressure generator, which is equipped with a dilute solution switching valve E; the other is the inlet pipe of the heat pump generator, which is equipped with a dilute solution switching valve F. A refrigerant water regulating valve G is installed on the refrigerant water U-shaped pipe from the condenser to the evaporator; A cooling water switching valve H is installed on the cooling water pipe leading to the condenser, a cooling water switching valve I is installed on the cooling water pipe leading to the absorber, and a hot water switching valve J is installed on the hot water pipes leading to the absorber and the condenser.

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