CN107677002B - Low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method - Google Patents
Low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method Download PDFInfo
- Publication number
- CN107677002B CN107677002B CN201710849069.5A CN201710849069A CN107677002B CN 107677002 B CN107677002 B CN 107677002B CN 201710849069 A CN201710849069 A CN 201710849069A CN 107677002 B CN107677002 B CN 107677002B
- Authority
- CN
- China
- Prior art keywords
- absorber
- heat
- chemical reaction
- generator
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
- F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
- F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B15/00—Sorption machines, plants or systems, operating continuously, e.g. absorption type
- F25B15/02—Sorption machines, plants or systems, operating continuously, e.g. absorption type without inert gas
- F25B15/04—Sorption machines, plants or systems, operating continuously, e.g. absorption type without inert gas the refrigerant being ammonia evaporated from aqueous solution
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/27—Relating to heating, ventilation or air conditioning [HVAC] technologies
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/62—Absorption based systems
Abstract
The invention discloses a low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and a method. The high-pressure gaseous refrigeration working medium ammonia and carbon dioxide enter a chemical reaction cooler, are absorbed by working liquid and generate ammonium carbamate to release heat, a resultant is dissolved in the working liquid, a mixed solution enters a chemical reaction evaporator through a heat regenerator and a throttling device, the ammonium carbamate is decomposed to generate ammonia and carbon dioxide and is evaporated, heat is absorbed, the ammonia and the carbon dioxide enter a first absorber and a second absorber to be selectively absorbed respectively, and the high-pressure gaseous refrigeration working medium is generated in the first generator and the second generator respectively. The invention realizes refrigeration/heating by utilizing reversible chemical reaction, has higher performance coefficient compared with phase-change refrigeration/heating, can realize the purpose of improving the pressure of mixed gas under larger compression ratio, and can conveniently adjust the flow proportion of gaseous refrigeration working media.
Description
Technical Field
The invention belongs to the technical field of air conditioning equipment, and particularly relates to a low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method.
Background
The existing artificial refrigeration method can be generally divided into two main categories of physical method and chemical method, and most refrigeration methods belong to the physical method. The refrigeration application is wide by using the heat absorption effect of the substance phase change, but the unit mass refrigerating capacity and the performance coefficient of the phase change refrigeration are not high due to the influence of the thermal property of the refrigerant. Therefore, it is considered to use a chemical method to achieve the refrigeration.
Ammonium carbamate is an intermediate product for synthesizing urea, is white solid, is unstable, and is easy to decompose when heated. The decomposition reaction of ammonium carbamate to form carbon dioxide and ammonia is highly endothermic with a heat of chemical reaction of 2010 KJ/KG. The decomposition of ammonium carbamate is closely related to temperature and pressure and can be achieved by reducing the pressure below the saturation pressure corresponding to the set temperature or by increasing the temperature above the saturation temperature corresponding to the set pressure. The carbon dioxide and the ammonia gas can carry out chemical reaction under different temperature conditions, and the ammonium carbamate (NH) can be generated under the conditions of room temperature, one atmosphere pressure and no participation of steam2COONH4) The synthesis reaction process is exothermic. Thus, the reversible chemical reaction of carbon dioxide and ammonia gas can be utilized to realize the preparationCold or heat. Because the synthesis and decomposition of ammonium carbamate are closely related to temperature and pressure, the cyclic compression ratio is large under the working condition of refrigeration or heating, the compression ratio is large according to the balance pressure required by the synthesis reaction and the decomposition reaction, which can reach more than 18, and a device is needed to realize the boosting process of the working medium under the large compression ratio.
Under the condition of large compression ratio, if a single-stage vapor compression type refrigeration technology is adopted, the actual compression process can be greatly deviated from the isentropic compression process, the exhaust temperature of the compressor is increased, the efficiency is reduced, the power consumption is increased, even the decomposition of refrigerant and lubricating oil in the system is caused, the operation condition is deteriorated, and the normal work of the compressor is damaged. Absorption refrigeration technology is therefore considered. The absorption type refrigeration/heating technology is a refrigeration/heating technology driven by heat energy, and is different from compression type refrigeration/heating in that the absorption process and the generation process of an absorbent to a refrigerant are utilized to change low-pressure steam into high-pressure steam, so that the pressure lifting process under the condition of a larger compression ratio can be realized. Meanwhile, the absorption refrigeration/heat pump unit utilizes heat energy as power, only consumes little mechanical energy, and can utilize heat energy with lower grade, such as waste heat, solar energy and the like.
Chinese patent application 201480031214.3 discloses an absorption refrigeration system comprising a dual refrigerant and a liquid working fluid, which uses ammonia and carbon dioxide as the refrigerant, the system has the limitations that: firstly, the system utilizes the phase change process of ammonia and carbon dioxide to realize refrigeration, which is different from the refrigeration mode of the invention, and because of the limitation of gas refrigerant (the critical temperature of carbon dioxide is too low), the condensation process of carbon dioxide in a condenser is generally difficult to realize under the natural cooling condition; secondly, in the absorber, under the conditions of absorption temperature and absorption pressure, ammonia and carbon dioxide are difficult to chemically react; third, the absorption refrigeration system provided in the patent only comprises one absorber for absorbing ammonia and carbon dioxide, but because of the limitation of the absorbent, it is difficult to simultaneously physically dissolve and desorb acidic and alkaline gases in one absorber, and the absorption refrigeration system provided in the patent is difficult to adjust the gas mass flow ratio of ammonia and carbon dioxide to meet the chemical reaction requirement of the system, which causes the pressure of the redundant gas refrigerant to be raised, resulting in energy loss.
Disclosure of Invention
The invention aims to provide a low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device which utilizes reversible chemical reaction to realize refrigeration/heating, has higher performance coefficient compared with liquid vaporization phase change refrigeration/heating, can respectively increase the pressure of gaseous refrigeration working media ammonia and carbon dioxide under a larger compression ratio, and can conveniently adjust the flow ratio of two gaseous refrigeration working media meeting the chemical reaction.
Another object of the present invention is to provide a method for cooling/heating using the circulation device.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device comprises a chemical reaction cooler 1, a throttling device, a chemical reaction evaporator 4, a heat regenerator 7, a first absorber 8, a first heat exchanger 11, a first generator 12, a second absorber 14, a second heat exchanger 17 and a second generator 18;
the gas outlet of the first generator 12 and the gas outlet of the second generator 18 are respectively connected with the gas inlet of the chemical reaction cooler 1, the liquid inlet of the chemical reaction cooler 1 is connected with the low-temperature side outlet of the heat regenerator 7, and the low-temperature side inlet of the heat regenerator 7 is connected with the liquid outlet of the chemical reaction evaporator 4; the liquid outlet of the chemical reaction cooler 1 is connected with the high-temperature side inlet of the heat regenerator 7, the high-temperature side outlet of the heat regenerator 7 is connected with the inlet of the throttling device, and the outlet of the throttling device is connected with the liquid inlet of the chemical reaction evaporator 4;
a gas outlet of the chemical reaction evaporator 4 is connected to a gas inlet of the first absorber 8, and a gas outlet of the first absorber 8 is connected to a gas inlet of the second absorber 14; a liquid inlet of the first absorber 8 is connected with a high-temperature side liquid outlet of the first heat exchanger 11, a high-temperature side liquid inlet of the first heat exchanger 11 is connected with a liquid outlet of the first generator 12, a liquid inlet of the first generator 12 is connected with a low-temperature side liquid outlet of the first heat exchanger 11, and a low-temperature side liquid inlet of the first heat exchanger 11 is connected with a liquid outlet of the first absorber 8;
the liquid inlet of the second absorber 14 is connected with the high-temperature side liquid outlet of the second heat exchanger 17, the high-temperature side liquid inlet of the second heat exchanger 17 is connected with the liquid outlet of the second generator 18, the liquid inlet of the second generator 18 is connected with the low-temperature side liquid outlet of the second heat exchanger 17, and the low-temperature side liquid inlet of the second heat exchanger 17 is connected with the liquid outlet of the second absorber 14.
Furthermore, the first gaseous refrigeration working medium is ammonia gas, the second gaseous refrigeration working medium is carbon dioxide, an absorbent for selectively absorbing alkaline gas is arranged in the first absorber, and an absorbent for selectively absorbing acidic gas is arranged in the second absorber; or the first gaseous refrigeration working medium is carbon dioxide, the second gaseous refrigeration working medium is ammonia gas, the first absorber is an absorbent for selectively absorbing acid gas, and the second absorber is an absorbent for selectively absorbing alkaline gas; the working liquid is organic alcohol.
Further, the organic alcohol is one or a mixture of propylene glycol and ethylene glycol.
Furthermore, the absorbent for selectively absorbing the alkaline gas is LiSCN, NaSCN or LiNO3(ii) a The absorbent for selectively absorbing the acid gas is organic amine or ionic liquid.
Furthermore, a cooling water or heat medium water pipeline of the chemical reaction cooler 1, a cooling water or heat medium water pipeline of the first absorber 8 and a cooling water or heat medium water pipeline of the second absorber 14 are respectively arranged in the chemical reaction cooler 1, the first absorber 8 and the second absorber 14, a heat source of the first generator 12 and a heat source of the second generator 18 are respectively arranged in the first generator 12 and the second generator 18, and the bottom of the chemical reaction evaporator 4 is connected with a chilled water or low-temperature heat source pipeline.
Further, the throttling device is a U-shaped pipe, a capillary pipe or a throttling valve, and preferably is a U-shaped pipe.
The method for refrigerating and heating by utilizing the circulating device comprises the following steps:
step 1: the first generator and the second generator respectively output a first gaseous refrigerant and a second gaseous refrigerant under a high pressure state, the first gaseous refrigerant and the second gaseous refrigerant enter the chemical reaction cooler and are absorbed and reacted by working liquid, reaction products are dissolved in the working liquid to form a mixed solution, and the mixed solution is cooled by cooling water or heats heating medium water;
step 2: the mixed solution enters a chemical reaction evaporator through a throttling device, and a reaction product is decomposed and absorbs heat at low temperature and low pressure to generate a first gaseous refrigerant and a second gaseous refrigerant which are evaporated from working liquid to cool refrigerant water or absorb heat of a low-temperature heat source;
and step 3: the working liquid of the chemical reaction evaporator is subcooled by the heat regenerator, and then is sent into the chemical reaction cooler;
and 4, step 4: the first and second gaseous refrigeration working media enter a first absorber, the first gaseous refrigeration working media are selectively absorbed by the absorber, the released heat enters cooling water or heating medium water, and then the solution is sent to a first generator to be heated to generate the first gaseous refrigeration working media in a high-pressure state; the second gaseous refrigerant enters the second absorber and is absorbed by the absorbent, the released heat enters the cooling water or the heating medium water, the solution is sent to the second generator to be heated to generate the second gaseous refrigerant in a high-pressure state, and the steps are repeated to form a cycle.
Furthermore, the flow ratio of the first gaseous refrigerant and the second gaseous refrigerant is adjusted by adjusting the size, the structure or the operation parameters of the first absorber and the second absorber.
Furthermore, the first gaseous refrigeration working medium is ammonia gas, the second gaseous refrigeration working medium is carbon dioxide, an absorbent for selectively absorbing alkaline gas is arranged in the first absorber, and an absorbent for selectively absorbing acidic gas is arranged in the second absorber; or the first gaseous refrigeration working medium is carbon dioxide, the second gaseous refrigeration working medium is ammonia gas, the first absorber is an absorbent for selectively absorbing acid gas, and the second absorber is an absorbent for selectively absorbing alkaline gas; the working liquid is organic alcohol.
Further, the organic alcohol is one or a mixture of two of propylene glycol and ethylene glycol, and is preferably propylene glycol.
Furthermore, the absorbent for selectively absorbing the alkaline gas is LiSCN, NaSCN or LiNO3(ii) a The absorbent for selectively absorbing the acid gas is organic amine or ionic liquid.
Has the advantages that:
(1) the invention utilizes the chemical reaction heat of the reversible chemical reaction and the liquid vaporization heat to realize refrigeration/heating, compared with liquid vaporization phase change refrigeration/heating, the refrigeration quantity or the heating quantity is larger, and the chemical reaction heat is much larger than the phase change latent heat, so the invention has higher performance coefficient.
(2) Compared with the condition that only one absorber is used for absorbing the mixed gas, the invention has the advantages that ① can increase the pressure of the mixed gas under the condition of larger compression ratio, the pressure of the two gases is difficult to increase simultaneously by the two gases in one absorber under the limitation of the absorber, the same pressure ratio is increased, ② can conveniently adjust the flow ratio of the two gases meeting the chemical reaction, and avoid the energy loss caused by the pressure increase of redundant gaseous refrigerant, and the mass flow ratio of the two gases needs to meet the chemical reaction requirement of the device, and the two absorbers are needed to adjust and adapt.
(3) The invention provides a specific working circulation mode for realizing refrigeration/heating by utilizing the chemical reaction heat and the liquid vaporization heat of the reversible chemical reaction, which comprises refrigeration working medium circulation, selective absorbent circulation and working liquid circulation and can realize the high-efficiency utilization of energy.
(4) The invention adopts the heat regenerator to supercool the solution from the cooler, recovers the cold quantity and improves the circulating refrigerating capacity and coefficient.
(5) The invention takes heat energy as a driving mode, can utilize low-grade heat sources such as waste heat, geothermal energy, solar energy and the like, improves the performance coefficient of the device, and generates cold or heat to meet the energy requirement of users. The device operates under negative pressure, is safe and reliable, and has no damage to the environment.
Drawings
Fig. 1 is a schematic diagram of a low-grade heat-driven absorption chemical reaction refrigeration/heating cycle device.
Detailed Description
The invention will be better understood from the following examples. However, those skilled in the art will readily appreciate that the description of the embodiments is only for illustrating the present invention and should not be taken as limiting the invention as detailed in the claims.
The invention relates to a low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device which comprises a working medium circulating loop, a selective absorbent circulating loop and a working liquid circulating loop.
As shown in fig. 1, the circulation device provided by the present invention comprises a chemical reaction cooler 1, a throttling device, a chemical reaction evaporator 4, a heat regenerator 7, a first absorber 8, a first heat exchanger 11, a first generator 12, a second absorber 14, a second heat exchanger 17, and a second generator 18;
the gas outlet of the first generator 12 and the gas outlet of the second generator 18 are respectively connected with the gas inlet of the chemical reaction cooler 1, the liquid inlet of the chemical reaction cooler 1 is connected with the low-temperature side outlet of the heat regenerator 7, and the low-temperature side inlet of the heat regenerator 7 is connected with the liquid outlet of the chemical reaction evaporator 4; the liquid outlet of the chemical reaction cooler 1 is connected with the high-temperature side inlet of the heat regenerator 7, the high-temperature side outlet of the heat regenerator 7 is connected with the inlet of the throttling device, and the outlet of the throttling device is connected with the liquid inlet of the chemical reaction evaporator 4;
a gas outlet of the chemical reaction evaporator 4 is connected to a gas inlet of the first absorber 8, and a gas outlet of the first absorber 8 is connected to a gas inlet of the second absorber 14; a liquid inlet of the first absorber 8 is connected with a high-temperature side liquid outlet of the first heat exchanger 11, a high-temperature side liquid inlet of the first heat exchanger 11 is connected with a liquid outlet of the first generator 12, a liquid inlet of the first generator 12 is connected with a low-temperature side liquid outlet of the first heat exchanger 11, and a low-temperature side liquid inlet of the first heat exchanger 11 is connected with a liquid outlet of the first absorber 8;
the liquid inlet of the second absorber 14 is connected with the high-temperature side liquid outlet of the second heat exchanger 17, the high-temperature side liquid inlet of the second heat exchanger 17 is connected with the liquid outlet of the second generator 18, the liquid inlet of the second generator 18 is connected with the low-temperature side liquid outlet of the second heat exchanger 17, and the low-temperature side liquid inlet of the second heat exchanger 17 is connected with the liquid outlet of the second absorber 14.
The first gaseous refrigeration working medium is ammonia gas, the second gaseous refrigeration working medium is carbon dioxide, an absorbent for selectively absorbing alkaline gas is arranged in the first absorber, and an absorbent for selectively absorbing acidic gas is arranged in the second absorber; or the first gaseous refrigeration working medium is carbon dioxide, the second gaseous refrigeration working medium is ammonia gas, the first absorber is an absorbent for selectively absorbing acid gas, and the second absorber is an absorbent for selectively absorbing alkaline gas; the working liquid is organic alcohol.
The invention mainly utilizes the decomposition process of the ammonium carbamate to absorb a large amount of heat for refrigeration, comprises chemical reaction heat and vaporization heat, utilizes the heat release in the synthesis reaction process of the ammonium carbamate and the heat absorption released in the absorber to realize heating in a heat pump mode, and has higher coefficient of performance compared with the traditional adsorption refrigeration/heating because the chemical reaction heat is much larger than the latent heat of phase change. Meanwhile, two solution loops consisting of a generator, an absorber and a heat exchanger are respectively adopted to respectively increase the pressure of the gaseous refrigeration working medium under the condition of large compression ratio, so that the waste heat resource can be effectively utilized, and the performance coefficient of the device is improved.
Reversible chemical reaction between ammonia and carbon dioxide:
in one embodiment, the first gaseous refrigerant is ammonia gas, the second gaseous refrigerant is carbon dioxide, and accordingly, the absorbent in the first absorber is a solvent for selectively absorbing alkaline gas, and the absorbent in the second absorber is a solvent for selectively absorbing acidic gas. Ammonia and carbon dioxide enter a first absorber, the ammonia is absorbed by an absorbent which selectively absorbs alkaline gas in the first absorber, and then the solution is sent to a first generator to be heated to generate ammonia in a high-pressure state; the carbon dioxide enters the second absorber, is absorbed by the absorbent for absorbing the acid gas in the second absorber, and the solution is sent to the second generator and is heated to generate the carbon dioxide in a high-pressure state.
In another embodiment, the first gaseous refrigeration medium is carbon dioxide and the second gaseous refrigeration medium is ammonia, and accordingly, the absorbent in the first absorber is a solvent that selectively absorbs acidic gases and the absorbent in the second absorber is a solvent that selectively absorbs basic gases. Ammonia and carbon dioxide enter a first absorber, the carbon dioxide is absorbed by an absorbent which selectively absorbs acid gas in the first absorber, and then the solution is sent to a first generator to be heated to generate carbon dioxide in a high-pressure state; the ammonia enters the second absorber, is absorbed by the absorbent for absorbing alkaline gas in the second absorber, and the solution is sent to the second generator and heated to generate the ammonia in a high-pressure state.
The first absorber and the second absorber are arranged to utilize two different selective absorbents, and one absorber is limited by the absorbents, so that the acid and alkali gases are difficult to be physically dissolved and desorbed by one absorbent and no chemical reaction occurs. The two absorbers respectively absorb the first and second gaseous refrigeration working media with low temperature and low pressure, and the two generators respectively output the first and second gaseous refrigeration working media with high pressure, so that the first and second gaseous refrigeration working media are respectively pressurized under a larger compression ratio. The invention can conveniently adjust the flow ratio of the two gases meeting the chemical reaction by adjusting the size, the structure or the operation parameters of the first absorber and the second absorber.
The invention is provided with a heat regenerator 7, and the working liquid from the chemical reaction evaporator 4 overcools the solution from the chemical reaction cooler 1 through the heat regenerator 7. The present invention improves the refrigeration capacity and the refrigeration coefficient of the cycle by providing the regenerator 7 to recover the refrigeration capacity, and all similar alternatives and modifications will be apparent to those skilled in the art and are considered to be included within the spirit, scope and content of the present invention. It will be apparent to those skilled in the art that the technology of the present invention can be implemented by modifying or appropriately combining the regenerator of the present invention without departing from the spirit, scope and content of the present invention.
The chemical reaction cooler 1, the first absorber 8 and the second absorber 14 are respectively provided with a chemical reaction cooler cooling water or heat medium water pipeline 2, a first absorber cooling water or heat medium water pipeline 9 and a second absorber cooling water or heat medium water pipeline 15, a first generator heat source 13 and a second generator heat source 19 are respectively arranged in the first generator 12 and the second generator 18, and the bottom of the chemical reaction evaporator 4 is connected with a chilled water or low-temperature heat source pipeline 5, which is well known by persons skilled in the art.
The throttling device of the invention includes but is not limited to a U-shaped pipe, a capillary pipe or a throttling valve. Because the absolute value of the throttling depressurization is smaller, the throttling device is preferably a U-shaped pipe, is simple and low in cost, and can meet the requirements. The present invention is directed to throttling pressure reduction by providing a throttling device, all such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and content of the invention. It will be apparent to those skilled in the art that the technology of the present invention can be implemented by modifying or appropriately combining the throttle devices described in the present invention without departing from the spirit, scope and spirit of the invention.
The present invention further includes a solution pump 6, a first generation pump 10, and a second generation pump 16, which are respectively disposed between the chemical reaction cooler 1 and the chemical reaction evaporator 4, between the first absorber 8 and the first generator 12, and between the second absorber 14 and the second generator 18, for transferring a solution, which is well known to those skilled in the art.
The method for refrigerating and heating by using the circulating device comprises the following steps:
step 1: the first generator and the second generator respectively output a first gaseous refrigerant and a second gaseous refrigerant under a high pressure state, the first gaseous refrigerant and the second gaseous refrigerant enter the chemical reaction cooler and are absorbed and reacted by working liquid, reaction products are dissolved in the working liquid to form a mixed solution, and the mixed solution is cooled by cooling water or heats heating medium water;
step 2: the mixed solution enters a chemical reaction evaporator through a throttling device, and a reaction product is decomposed and absorbs heat at low temperature and low pressure to generate a first gaseous refrigerant and a second gaseous refrigerant which are evaporated from working liquid to cool refrigerant water or absorb heat of a low-temperature heat source;
and step 3: the working liquid of the chemical reaction evaporator is subcooled by the heat regenerator, and then is sent into the chemical reaction cooler;
and 4, step 4: the first and second gaseous refrigeration working media enter a first absorber, the first gaseous refrigeration working media are selectively absorbed by the absorber, the released heat enters cooling water or heating medium water, and then the solution is sent to a first generator to be heated to generate the first gaseous refrigeration working media in a high-pressure state; the second gaseous refrigerant enters the second absorber and is absorbed by the absorbent, the released heat enters the cooling water or the heating medium water, the solution is sent to the second generator to be heated to generate the second gaseous refrigerant in a high-pressure state, and the steps are repeated to form a cycle.
The invention can adjust the flow ratio of the first gaseous refrigerant and the second gaseous refrigerant by adjusting the size, the structure or the operation parameters of the first absorber and the second absorber. According to the mass flow ratio of two gas refrigerants, the sizes of the two absorbers, the pipe diameters of heat exchange pipelines, pipes, the surface structures of the pipes, the arrangement of pipe bundles, the pipe spacing, the structures and the heights of liquid distributors and the like are designed when the absorbers are designed; during operation, the operation parameters of the two absorbers, such as the spraying density of concentrated solution, the cooling water flow, the inlet temperature, the solution circulation amount and the like, are respectively adjusted to respectively adjust the mass flow of the two gaseous refrigeration working media, so that the flow ratio of the two gaseous refrigeration working media meets the requirement of reversible chemical reaction, and the pressure rise of redundant gaseous refrigeration working media is avoided to cause energy loss. The flow regulation of the single gas refrigerant can refer to the energy regulation mode of a single-effect lithium bromide absorption refrigerator. When the single-effect lithium bromide absorption refrigerator operates under variable working conditions, the flow of the refrigerant is adjusted by adjusting the operation parameters such as the temperature and the flow of the cooling water inlet, the solution circulation amount and the like, and the refrigerating capacity of the device is changed, so that the single-effect lithium bromide absorption refrigerator obtains the optimal refrigerating effect.
The first gaseous refrigeration working medium is ammonia gas, the second gaseous refrigeration working medium is carbon dioxide, an absorbent for selectively absorbing alkaline gas is arranged in the first absorber, and an absorbent for selectively absorbing acidic gas is arranged in the second absorber; or the first gaseous refrigeration working medium is carbon dioxide, the second gaseous refrigeration working medium is ammonia gas, the first absorber is an absorbent for selectively absorbing acid gas, and the second absorber is an absorbent for selectively absorbing alkaline gas; the working liquid is organic alcohol.
The absorbent for selectively absorbing an alkaline gas according to the present invention is an absorbent conventionally used by those skilled in the art, and may be any of various agents suitable for absorbing an alkaline gas but incapable of absorbing an acid gas. Examples of suitable absorbents for selectively absorbing alkaline gases include a wide range of reagents, and the present invention ensures that ammonia gas and carbon dioxide at low temperature and low pressure are respectively absorbed in two absorbers and ammonia gas and carbon dioxide at high temperature and high pressure are respectively output in two generators by the absorbents for selectively absorbing alkaline gases. In certain embodiments, the absorbent for selectively absorbing alkaline gases of the present invention is LiSCN, NaSCN or LiNO3。
The absorbent for selectively absorbing an acid gas according to the present invention is an absorbent conventionally used by those skilled in the art, and may be any of various agents suitable for absorbing an acid gas but incapable of absorbing an alkaline gas. Examples of suitable absorbents for selectively absorbing acid gases include a wide range of reagents, and the present invention ensures that ammonia gas and carbon dioxide at low temperature and low pressure are respectively absorbed in two absorbers and ammonia gas and carbon dioxide at high temperature and high pressure are respectively output in two generators by the absorbent for selectively absorbing acid gases. The absorbent for selectively absorbing acid gas includes, but is not limited to, organic amine absorbent, ionic liquid. The organic amine absorbent includes, but is not limited to, one or more of Monoethanolamine (MEA), Diethanolamine (DEA), Triethanolamine (TEA), and Methyldiethanolamine (MDEA). The ionic liquid comprises but is not limited to one or more of [ apbim ] BF4, [ bmim ] [ PF6] and [ bmim ] [ BF4 ].
The working fluid of the present invention may be any of a variety of reagents suitable for dissolving the reaction product, increasing the heat flux density, and increasing the rate of chemical reaction. Examples of suitable working fluids include a wide range of reagents that have the function of dissolving the reaction product, increasing the heat flux density and increasing the rate of chemical reaction. Working liquids described herein include, but are not limited to, organic alcohols. In certain embodiments, the organic alcohol is one or a mixture of propylene glycol and ethylene glycol; in a preferred embodiment, the organic alcohol is propylene glycol.
The invention can realize refrigeration cycle by utilizing reversible chemical reaction, ammonium carbamate is decomposed at low temperature and low pressure in the chemical reaction evaporator to generate ammonia gas and carbon dioxide, and a large amount of heat (including chemical reaction heat and vaporization heat) is absorbed for refrigeration.
The invention can realize heat pump circulation by utilizing reversible chemical reaction, the refrigeration working medium ammonia and carbon dioxide react in a chemical reaction cooler at high temperature and high pressure to generate ammonium carbamate, and the released heat enters heat medium water to output heat; decomposing ammonium carbamate in a chemical reaction evaporator to absorb heat of a low-temperature heat source in a heat transfer pipe; selectively absorbing ammonia and carbon dioxide as refrigerating media in a first absorber and a second absorber respectively by using an absorbent, and outputting heat after the released heat enters hot media water; in the first generator and the second generator, the heat source is driven to heat the solution to generate ammonia gas and carbon dioxide respectively.
Example 1
The first gaseous refrigerant adopted in this embodiment is ammonia, the second gaseous refrigerant is carbon dioxide, the working liquid is propylene glycol, and the absorbent in the first absorber is LiNO3Second, secondThe absorbent in the absorber is ionic liquid [ bmim][PF6]。
As shown in fig. 1, the circulation device of the present embodiment includes a chemical reaction cooler 1, a chemical reaction cooler cooling water or heat medium water pipe 2, a U-shaped pipe 3, a chemical reaction evaporator 4, a chilled water or low temperature heat source pipe 5, a solution pump 6, a regenerator 7, a first absorber 8, a first absorber cooling water or heat medium water pipe 9, a first generator pump 10, a first heat exchanger 11, a first generator 12, a first generator heat source 13, a second absorber 14, a second absorber cooling water or heat medium water pipe 15, a second generator pump 16, a second heat exchanger 17, a second generator 18, a second generator heat source 19;
the gas outlet of the first generator 12 and the gas outlet of the second generator 18 are respectively connected with the gas inlet of the chemical reaction cooler 1, the liquid inlet of the chemical reaction cooler 1 is connected with the low-temperature side outlet of the heat regenerator 7, the low-temperature side inlet of the heat regenerator 7 is connected with the outlet of the solution pump 6, and the inlet of the solution pump 6 is connected with the liquid outlet of the chemical reaction evaporator 4; the liquid outlet of the chemical reaction cooler 1 is connected with the high-temperature side inlet of the heat regenerator 7, the high-temperature side outlet of the heat regenerator 7 is connected with the inlet of the U-shaped pipe 3, and the outlet of the U-shaped pipe 3 is connected with the liquid inlet of the chemical reaction evaporator 4;
a gas outlet of the chemical reaction evaporator 4 is connected to a gas inlet of the first absorber 8, and a gas outlet of the first absorber 8 is connected to a gas inlet of the second absorber 14; a liquid inlet of the first absorber 8 is connected with a high-temperature side liquid outlet of the first heat exchanger 11, a high-temperature side liquid inlet of the first heat exchanger 11 is connected with a liquid outlet of the first generator 12, a liquid inlet of the first generator 12 is connected with a low-temperature side liquid outlet of the first heat exchanger 11, a low-temperature side liquid inlet of the first heat exchanger 11 is connected with an outlet of the first generating pump 10, and an inlet of the first generating pump 10 is connected with a liquid outlet of the first absorber 8;
a liquid inlet of the second absorber 14 is connected with a high-temperature side liquid outlet of the second heat exchanger 17, a high-temperature side liquid inlet of the second heat exchanger 17 is connected with a liquid outlet of the second generator 18, a liquid inlet of the second generator 18 is connected with a low-temperature side liquid outlet of the second heat exchanger 17, a low-temperature side liquid inlet of the second heat exchanger 17 is connected with an outlet of the second generating pump 16, and an inlet of the second generating pump 16 is connected with a liquid outlet of the second absorber 14;
the chemical reaction cooler 1, the first absorber 8 and the second absorber 14 are respectively provided with a chemical reaction cooler cooling water or heat medium water pipeline 2, a first absorber cooling water or heat medium water pipeline 9 and a second absorber cooling water or heat medium water pipeline 15, the first generator 12 and the second generator 18 are respectively provided with a first generator heat source 13 and a second generator heat source 19, and the bottom of the chemical reaction evaporator 4 is connected with a chilled water or low-temperature heat source pipeline 5.
The cooling/heating method of the present embodiment includes the steps of:
step 1: the first generator 12 and the second generator 18 respectively output refrigeration working media ammonia and carbon dioxide in a high-pressure state under the drive of a heat source, the ammonia and the carbon dioxide enter the chemical reaction cooler 1, are absorbed by propylene glycol and react to generate ammonium carbamate, and the ammonium carbamate is dissolved in the propylene glycol to form a mixed solution, releases heat, and is cooled by cooling water or heated by heating water (to realize heating);
step 2: the mixed solution enters a chemical reaction evaporator 4 through a U-shaped pipe 3 of a throttling device, ammonium carbamate is decomposed and absorbs heat at low temperature and low pressure to generate ammonia gas and carbon dioxide, the ammonia gas and the carbon dioxide are evaporated from propylene glycol to absorb heat, and the temperature of chilled water is reduced (refrigeration is realized) or the heat of a low-temperature heat source is absorbed;
and step 3: the propylene glycol in the chemical reaction evaporator 4 supercools the liquid from the chemical reaction cooler 1 through a solution pump 6 and a heat regenerator 7, and then is sent into the chemical reaction cooler 1;
and 4, step 4: ammonia gas and carbon dioxide enter a first absorber 8, the ammonia gas is selectively absorbed by an absorbent, released heat enters cooling water or heating medium water, then the solution is sent to a first generator 12 by a first generating pump 10, and a heat source is driven to heat the solution in the first generator 12 to generate ammonia gas in a high-pressure state; the carbon dioxide which is not selectively absorbed enters the second absorber 14, is absorbed by the absorbent, the released heat enters cooling water or heating medium water, the solution in the absorber is sent to the second generator 18 by the second generating pump 16, the heat source is driven to heat the solution in the second generator 18 to generate the carbon dioxide in a high-pressure state, and the steps are repeated to form a cycle.
Compared with an absorption refrigeration system only comprising one absorber, the invention adjusts the flow ratio of two gases meeting the chemical reaction by arranging two absorbers to respectively absorb ammonia gas and carbon dioxide. Otherwise, the volume flow of the absorption gas is unbalanced due to the change of the absorption condition, and if the pressure of the gas refrigerant with the unbalanced flow proportion is increased, a large amount of certain gas finally cannot participate in the reaction and cannot play the roles of refrigeration and heating. For example, under the drive of a low-grade heat source at 100 ℃, when the evaporation temperature is 10 ℃ and the cooling temperature is 40 ℃, the absorption volume flow of ammonia and carbon dioxide is about 1: 1, wherein about 50% of ammonia can not participate in the reaction, so that the energy consumption can be saved by about 50% after the selective absorption device is adopted.
Claims (9)
1. A low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device is characterized by comprising a chemical reaction cooler (1), a throttling device, a chemical reaction evaporator (4), a heat regenerator (7), a first absorber (8), a first heat exchanger (11), a first generator (12), a second absorber (14), a second heat exchanger (17) and a second generator (18);
the gas outlet of the first generator (12) and the gas outlet of the second generator (18) are respectively connected with the gas inlet of the chemical reaction cooler (1), the liquid inlet of the chemical reaction cooler (1) is connected to the low-temperature side outlet of the heat regenerator (7), and the low-temperature side inlet of the heat regenerator (7) is connected with the liquid outlet of the chemical reaction evaporator (4); the liquid outlet of the chemical reaction cooler (1) is connected with the high-temperature side inlet of the heat regenerator (7), the high-temperature side outlet of the heat regenerator (7) is connected with the inlet of the throttling device, and the outlet of the throttling device is connected with the liquid inlet of the chemical reaction evaporator (4);
a gas outlet of the chemical reaction evaporator (4) is connected to a gas inlet of the first absorber (8), and a gas outlet of the first absorber (8) is connected with a gas inlet of the second absorber (14); a liquid inlet of the first absorber (8) is connected with a high-temperature side liquid outlet of the first heat exchanger (11), a high-temperature side liquid inlet of the first heat exchanger (11) is connected with a liquid outlet of the first generator (12), a liquid inlet of the first generator (12) is connected with a low-temperature side liquid outlet of the first heat exchanger (11), and a low-temperature side liquid inlet of the first heat exchanger (11) is connected with a liquid outlet of the first absorber (8);
a liquid inlet of the second absorber (14) is connected with a high-temperature side liquid outlet of the second heat exchanger (17), a high-temperature side liquid inlet of the second heat exchanger (17) is connected with a liquid outlet of the second generator (18), a liquid inlet of the second generator (18) is connected with a low-temperature side liquid outlet of the second heat exchanger (17), and a low-temperature side liquid inlet of the second heat exchanger (17) is connected with a liquid outlet of the second absorber (14);
the first gaseous refrigeration working medium is ammonia gas, the second gaseous refrigeration working medium is carbon dioxide, the first absorber is an absorbent for selectively absorbing alkaline gas, and the second absorber is an absorbent for selectively absorbing acidic gas; alternatively, the first and second electrodes may be,
the first gaseous refrigerating working medium is carbon dioxide, the second gaseous refrigerating working medium is ammonia, the first absorber is an absorbent for selectively absorbing acid gas, and the second absorber is an absorbent for selectively absorbing alkaline gas.
2. The circulation device according to claim 1, wherein: the working liquid is organic alcohol.
3. The circulation device according to claim 1, wherein a cooling water or heat medium water pipeline of the chemical reaction cooler (1), a cooling water or heat medium water pipeline of the first absorber (8) and a cooling water or heat medium water pipeline of the second absorber (14) are respectively arranged in the chemical reaction cooler (1), the first absorber (8) and the second absorber (14), a heat source of the first generator (12) and a heat source of the second generator (18) are respectively arranged in the first generator (12) and the second generator (18), and a chilled water or low-temperature heat source pipeline is connected to the bottom of the chemical reaction evaporator (4).
4. The recycling apparatus according to claim 1, wherein the throttling means is a U-tube, a capillary tube or a throttle valve.
5. A method for cooling and heating by using the circulation device according to any one of claims 1 to 4, comprising the steps of:
step 1: the first generator and the second generator respectively output a first gaseous refrigerant and a second gaseous refrigerant under a high pressure state, the first gaseous refrigerant and the second gaseous refrigerant enter the chemical reaction cooler and are absorbed and reacted by working liquid, reaction products are dissolved in the working liquid to form a mixed solution, and the mixed solution is cooled by cooling water or heats heating medium water;
step 2: the mixed solution enters a chemical reaction evaporator through a throttling device, and a reaction product is decomposed and absorbs heat at low temperature and low pressure to generate a first gaseous refrigeration working medium and a second gaseous refrigeration working medium, and the first gaseous refrigeration working medium and the second gaseous refrigeration working medium are evaporated from working liquid to cool chilled water or absorb heat of a low-temperature heat source;
and step 3: the working liquid of the chemical reaction evaporator is subcooled by the heat regenerator, and then is sent into the chemical reaction cooler;
and 4, step 4: the first and second gaseous refrigeration working media enter a first absorber, the first gaseous refrigeration working media are selectively absorbed by the absorber, the released heat enters cooling water or heating medium water, and then the solution is sent to a first generator to be heated to generate the first gaseous refrigeration working media in a high-pressure state; the second gaseous refrigerant enters the second absorber and is absorbed by the absorbent, the released heat enters the cooling water or the heating medium water, the solution is sent to the second generator to be heated to generate the second gaseous refrigerant in a high-pressure state, and the steps are repeated to form a cycle.
6. A method of producing heat and cooling as claimed in claim 5, wherein the flow ratio of the first and second gaseous cooling medium is adjusted by adjusting the size, configuration or operating parameters of the first and second absorbers.
7. Method for producing cold and heat according to claim 5,
the first gaseous refrigeration working medium is ammonia gas, the second gaseous refrigeration working medium is carbon dioxide, the first absorber is an absorbent for selectively absorbing alkaline gas, and the second absorber is an absorbent for selectively absorbing acidic gas; alternatively, the first and second electrodes may be,
the first gaseous refrigeration working medium is carbon dioxide, the second gaseous refrigeration working medium is ammonia, the first absorber is an absorbent for selectively absorbing acid gas, and the second absorber is an absorbent for selectively absorbing alkaline gas;
the working liquid is organic alcohol.
8. A method for producing heat and cooling as recited in claim 7 wherein said organic alcohol is one or a mixture of propylene glycol and ethylene glycol.
9. A method for producing heat and cold as recited in claim 7 wherein said absorbent for selectively absorbing alkaline gas is LiSCN, NaSCN or LiNO3(ii) a The absorbent for selectively absorbing the acid gas is organic amine or ionic liquid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710849069.5A CN107677002B (en) | 2017-09-18 | 2017-09-18 | Low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710849069.5A CN107677002B (en) | 2017-09-18 | 2017-09-18 | Low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107677002A CN107677002A (en) | 2018-02-09 |
| CN107677002B true CN107677002B (en) | 2020-02-18 |
Family
ID=61136836
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710849069.5A Active CN107677002B (en) | 2017-09-18 | 2017-09-18 | Low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107677002B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110081636A (en) * | 2019-04-19 | 2019-08-02 | 东南大学 | A kind of solution chiasma type ammonium hydroxide absorbs, reabsorbs formula heat pump system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1380525A (en) * | 2002-02-28 | 2002-11-20 | 浙江大学 | Refrigeration equipment with cryogenic refrigeration absorbent |
| CN102292608A (en) * | 2008-11-26 | 2011-12-21 | 纳幕尔杜邦公司 | Absorption cycle system having dual absorption circuits |
| CN102413901A (en) * | 2009-02-26 | 2012-04-11 | 北京联力源科技有限公司 | Apparatus and method for compressing co2, system and method for separating and recovering co2 |
| CN105264040A (en) * | 2013-05-28 | 2016-01-20 | 徐延杰 | Refrigeration system with dual refrigerants and liquid working fluids |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6598420B2 (en) * | 2001-06-26 | 2003-07-29 | Carrier Corporation | Heat exchanger for high stage generator of absorption chiller |
-
2017
- 2017-09-18 CN CN201710849069.5A patent/CN107677002B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1380525A (en) * | 2002-02-28 | 2002-11-20 | 浙江大学 | Refrigeration equipment with cryogenic refrigeration absorbent |
| CN102292608A (en) * | 2008-11-26 | 2011-12-21 | 纳幕尔杜邦公司 | Absorption cycle system having dual absorption circuits |
| CN102413901A (en) * | 2009-02-26 | 2012-04-11 | 北京联力源科技有限公司 | Apparatus and method for compressing co2, system and method for separating and recovering co2 |
| CN105264040A (en) * | 2013-05-28 | 2016-01-20 | 徐延杰 | Refrigeration system with dual refrigerants and liquid working fluids |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107677002A (en) | 2018-02-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103868278B (en) | Low-grade energy drives CO2absorption type cold-hot chp system | |
| CN109519243B (en) | Supercritical CO2 and ammonia water combined cycle system and power generation system | |
| CN104963732A (en) | Combined circulating energy supplying system | |
| CN107606816B (en) | Low-grade heat-driven adsorption type chemical reaction refrigeration heat pump circulating device and method | |
| CN112554983A (en) | Liquid carbon dioxide energy storage system and method coupled with kalina cycle | |
| Gao et al. | System principles and applications of hybrid sorption–compression heat pump–A review | |
| CN102322705B (en) | Circulating device combining diffusing absorption-type refrigeration and vapor compression refrigeration | |
| CN101776347B (en) | Absorption type refrigerating unit with pressure recovery part | |
| CN114198173B (en) | Electric cooling combined supply system integrating full-regenerative brayton cycle and absorption refrigeration | |
| CN110926108A (en) | Middle and low temperature industrial flue gas carbon dioxide capture system | |
| CN108148555B (en) | Refrigeration absorbent and waste heat driven absorption type deep refrigeration method | |
| CN107677002B (en) | Low-grade heat-driven absorption type chemical reaction refrigeration heat pump circulating device and method | |
| CN206131515U (en) | A air -cooled absorbed refrigeration machine for car | |
| CN110986418B (en) | Absorption type circulating system based on temperature rising and pressure rising technology | |
| CN103075835B (en) | Novel absorption type refrigeration and power-generation combining device | |
| CN109631413A (en) | A kind of absorption/compression mixture circulatory system adsorbing cooling air-breathing | |
| WO2023083242A1 (en) | Low-temperature cyclic power generation system and method with carbon dioxide gas as working medium | |
| CN103175332A (en) | Two-stage absorption refrigeration circulation system based on double working pairs and refrigeration method thereof | |
| CN105546870A (en) | Supergravity thermal drive refrigeration device and method | |
| CN107630727B (en) | Medium-low temperature heat energy driven power generation, refrigeration and carbon capture coupling system | |
| CN202361696U (en) | Heat pump circulating system and evaporation system | |
| CN109631405A (en) | A kind of boosting type heat chemistry adsorption heat pump circulatory system with cooling cycle | |
| Bula et al. | Thermodynamic simulation of a solar absorption refrigeration system, generator heat exchanger | |
| CN107726665B (en) | Two-stage compression refrigeration heat pump circulation device and method based on reversible chemisorption heat release | |
| CN113091349A (en) | High-efficient absorption heat pump |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |