CN112483207A - Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system - Google Patents

Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system Download PDF

Info

Publication number
CN112483207A
CN112483207A CN202011434998.8A CN202011434998A CN112483207A CN 112483207 A CN112483207 A CN 112483207A CN 202011434998 A CN202011434998 A CN 202011434998A CN 112483207 A CN112483207 A CN 112483207A
Authority
CN
China
Prior art keywords
double
carbon dioxide
effect absorption
outlet
supercritical carbon
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.)
Pending
Application number
CN202011434998.8A
Other languages
Chinese (zh)
Inventor
张峰
廖高良
谌冰洁
戴幸福
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hunan University
Original Assignee
Hunan University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hunan University filed Critical Hunan University
Priority to CN202011434998.8A priority Critical patent/CN112483207A/en
Publication of CN112483207A publication Critical patent/CN112483207A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K25/00Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
    • F01K25/08Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours
    • F01K25/10Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours the vapours being cold, e.g. ammonia, carbon dioxide, ether
    • F01K25/103Carbon dioxide
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D15/00Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
    • F01D15/10Adaptations for driving, or combinations with, electric generators
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K13/00General layout or general methods of operation of complete plants
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K13/00General layout or general methods of operation of complete plants
    • F01K13/006Auxiliaries or details not otherwise provided for
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K17/00Using steam or condensate extracted or exhausted from steam engine plant
    • F01K17/02Using steam or condensate extracted or exhausted from steam engine plant for heating purposes, e.g. industrial, domestic
    • F01K17/025Using steam or condensate extracted or exhausted from steam engine plant for heating purposes, e.g. industrial, domestic in combination with at least one gas turbine, e.g. a combustion gas turbine

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)

Abstract

The application discloses supercritical carbon dioxide circulation and double-effect absorption power cycle combined power generation system includes: the system comprises a supercritical carbon dioxide recompression circulation system as top circulation and a double-effect absorption power circulation system as bottom circulation, wherein the two subsystems are connected in a coupling mode through a generator. The double-effect absorption type power circulation system absorbs low-temperature waste heat of a supercritical carbon dioxide recompression circulation system through a low-concentration lithium bromide aqueous solution, and separates the lithium bromide aqueous solution into water vapor and a high-concentration saturated lithium bromide aqueous solution, wherein the water vapor expands in a high-pressure turbine to work, the high-concentration saturated lithium bromide aqueous solution further separates extra water vapor through a reheater, a throttle valve and a separator in sequence, the water vapor is mixed with high-pressure turbine expansion exhaust gas, and the mixture is subjected to heat absorption and temperature rise through the reheater and then further expands in a low-pressure turbine to work, so that the output power of the absorption type power circulation subsystem is improved, and the power generation efficiency of the combined power generation system is further improved.

Description

Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system
Technical Field
The application relates to the technical field of power generation systems, in particular to a supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system.
Background
In the field of power generation, thermal power generation still occupies an absolute dominant position; whether it is a coal-fired power plant with the largest market proportion, a nuclear power plant with an increasing specific gravity year by year, or a new energy power plant, such as a solar power plant and a geothermal power plant, and a distributed power plant which is popularized in recent years and uses a gas turbine area for power supply, etc., these power plants require an efficient thermodynamic system for converting thermal energy of a heat source or exhaust gas into mechanical energy.
The conventional steam power cycle is the most widely applied energy conversion mode in the field of thermal power generation at present, the cycle power generation technology tends to be mature, and in order to further improve the thermal power generation efficiency to relieve the energy crisis and the global environmental problem, a conversion thought is needed, so that the energy conversion mode is fundamentally innovated. The supercritical carbon dioxide brayton cycle is a very potential thermodynamic cycle mode, and is considered to be a promising main energy conversion mode in the field of thermal power generation to replace the traditional steam rankine cycle in the future. The supercritical carbon dioxide power cycle has the advantages that the special physical properties of the carbon dioxide working medium near the critical point are beneficial to obviously reducing the compression work of the compressor, so that the carbon dioxide needs to release a large amount of low-grade waste heat before entering the compressor to reduce the temperature of the carbon dioxide to be near the critical point, and the part of the waste heat is directly absorbed by a cold source, so that a large amount of cold source loss is caused. In order to further optimize the supercritical carbon dioxide power cycle, a power system suitable for a low-grade heat source is adopted to recycle the waste heat, so that the power generation efficiency of the whole system is improved.
The power system commonly used for the low-grade heat source mainly comprises an organic Rankine cycle, a kalina cycle, a transcritical carbon dioxide power cycle and a single-effect absorption power cycle, wherein working mediums of the organic Rankine cycle and the transcritical carbon dioxide power cycle are single fluids, and the pure fluids have phase change in the evaporation and condensation processes to ensure that the temperature of the fluids is highRemaining unchanged, the temperature difference between the respective working fluid and the heat source and heat sink is greater, resulting in a greater temperature difference
Figure BDA0002828192870000011
And (4) loss. The kalina cycle and the single-effect absorption power cycle still have great performance improvement space.
In summary, how to improve the power generation efficiency of the power generation system is a problem to be solved urgently by those skilled in the art.
Disclosure of Invention
In view of the above, an object of the present application is to provide a combined power generation system with supercritical carbon dioxide cycle and double-effect absorption type power cycle, which includes a supercritical carbon dioxide recompression cycle system and a double-effect absorption type power cycle system, and compared with the prior art that a mixture ammonia water is used, a cycle working medium of the double-effect absorption type power cycle system in the present application is a lithium bromide aqueous solution, and a saturation pressure of the lithium bromide aqueous solution can be significantly reduced by using a conventional cold source such as environmental water during absorption and condensation, so as to reduce turbine backpressure and improve turbine work capacity.
In order to achieve the above purpose, the present application provides the following technical solutions:
a supercritical carbon dioxide cycle and double-effect absorption power cycle combined power generation system, comprising: the system comprises a supercritical carbon dioxide recompression circulation system and a double-effect absorption power circulation system, wherein the supercritical carbon dioxide recompression circulation system and the double-effect absorption power circulation system are coupled and connected through a generator, low-temperature waste heat of the supercritical carbon dioxide recompression circulation system is absorbed through a circulation working medium in the double-effect absorption power circulation system, and the circulation working medium is a lithium bromide aqueous solution;
the generator is used for separating the low-concentration lithium bromide aqueous solution into water vapor and a first high-concentration saturated lithium bromide aqueous solution.
Preferably, the double-effect absorption power cycle system further comprises a first throttling valve for throttling and depressurizing the first high-concentration saturated lithium bromide aqueous solution and a separator connected with an outlet of the first throttling valve;
the separator is used for separating the first high-concentration saturated lithium bromide aqueous solution into water vapor and a second high-concentration saturated lithium bromide aqueous solution after being throttled and depressurized by the first throttle valve; and the concentration of the second high-concentration saturated lithium bromide aqueous solution is greater than that of the first high-concentration saturated lithium bromide aqueous solution.
Preferably, the double-effect absorption power cycle system further comprises a high-pressure turbine and a low-pressure turbine, and a steam outlet of the generator is connected with an inlet of the high-pressure turbine, so that the steam separated from the generator is expanded in the high-pressure turbine to produce work;
and the water vapor separated by the separator and the water vapor expanded and worked in the high-pressure turbine enter the low-pressure turbine to be further expanded and worked.
Preferably, the double-effect absorption power cycle system further comprises a first generator coaxially connected to both the high pressure turbine and the low pressure turbine, the high pressure turbine and the low pressure turbine averagely transfer mechanical energy to the first generator, and the first generator converts the mechanical energy into electrical energy.
Preferably, the double-effect absorption power cycle system further comprises a reheater, a hot-side fluid inlet of the reheater is connected with the solution outlet of the generator, and a hot-side fluid outlet of the reheater is connected with the inlet of the first throttling valve;
the steam outlet of the separator and the outlet of the high-pressure turbine are both connected with the cold-side fluid inlet of the reheater; the cold side fluid outlet of the reheater is connected to the inlet of the low pressure turbine.
Preferably, the double-effect absorption power cycle system further comprises a solution heat exchanger, a second throttling valve, an absorber and a pump; the solution outlet of the separator is connected to the hot-side fluid inlet of the solution heat exchanger, the hot-side fluid outlet of the solution heat exchanger is connected to the inlet of the second throttling valve, the outlet of the second throttling valve is connected to the solution inlet of the absorber, the outlet of the low-pressure turbine is connected to the steam inlet of the absorber, the solution outlet of the absorber is connected to the inlet of the pump, and the outlet of the pump is connected to the cold-side fluid inlet of the solution heat exchanger.
Preferably, the supercritical carbon dioxide recompression circulating system comprises a heat source, a high-temperature regenerator, a low-temperature regenerator, a main compressor, a cooler, a recompressor, a turbine and a second generator;
the cold side fluid outlet of the high-temperature regenerator is connected with the inlet of the heat source, the outlet of the heat source is connected with the inlet of the turbine, the outlet of the turbine is connected with the hot side fluid inlet of the high-temperature regenerator, the hot side fluid outlet of the high-temperature regenerator is connected with the hot side fluid inlet of the low-temperature regenerator, the inlet of the recompressor and the hot side fluid inlet of the generator are both connected with the hot side fluid outlet of the low-temperature regenerator, the hot side fluid outlet of the generator is connected with the hot side fluid inlet of the cooler, the hot side fluid outlet of the cooler is connected with the inlet of the main compressor, the outlet of the main compressor is connected with the cold side fluid inlet of the low-temperature regenerator, and the outlet of the recompressor and the cold side fluid inlet of the high-temperature regenerator are both connected with the cold side fluid outlet of the low-temperature regenerator.
Preferably, the turbine, the main compressor, the secondary compressor and the second generator are all coaxially arranged;
or the turbine comprises two stages, wherein one stage of turbine is coaxially connected with the main compressor and the secondary compressor, the other stage of turbine is a power turbine, and the power turbine is coaxially connected with the second generator.
Preferably, the heat source is a nuclear reactor of a nuclear power station, or a boiler of a coal-fired power station, or a heat collector of a solar power station, or a geothermal source of a geothermal power station, or a gas turbine tail gas of a gas turbine combined power generation system.
In the process of using the supercritical carbon dioxide circulation and double-effect absorption power circulation combined power generation system provided by the application, the low-temperature waste heat of the supercritical carbon dioxide recompression circulation system can be utilized by the double-effect absorption power circulation system, the supercritical carbon dioxide recompression circulation system and the double-effect absorption power circulation system are in coupling connection through the generator, the carbon dioxide working medium in the supercritical carbon dioxide recompression circulation system enters the generator, heat is transferred to the lithium bromide aqueous solution working medium in the double-effect absorption power circulation system, the lithium bromide aqueous solution absorbs heat and is heated to generate steam and a high-concentration lithium bromide aqueous solution, the steam expands and works in a high-pressure turbine, the high-concentration saturated lithium bromide aqueous solution further separates extra steam through a reheater, a throttle valve and a separator sequentially, the part of the steam is mixed with the high-pressure turbine expansion exhaust gas, absorbs heat and is heated through the reheater, and is further separated in a low-pressure reheater The medium expansion works to improve the output work of the absorption power circulation subsystem.
Compared with the prior art, the double-effect absorption type power cycle working medium provided by the application is the lithium bromide aqueous solution, and the saturation pressure of the lithium bromide aqueous solution can be obviously reduced by using a conventional cold source (such as environmental water) in the absorption and condensation process, so that the turbine back pressure in the double-effect absorption type power cycle system is reduced, and the work capacity of the turbine is improved. Compared with the single-effect absorption power cycle, the double-effect absorption power cycle can generate more work working media and higher low-pressure turbine inlet temperature, and the work doing capability of the turbine is improved, so that the power generation efficiency of the combined power generation system is improved.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic structural diagram of an embodiment of a combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system provided by the present application.
In fig. 1:
1 is a heat source, 2 is a turbine, 3 is a second generator, 4 is a high temperature regenerator, 5 is a low temperature regenerator, 6 is a cooler, 7 is a main compressor, 8 is a recompressor, 9 is a generator, 10 is a high pressure turbine, 11 is a low pressure turbine, 12 is a first generator, 13 is an absorber, 14 is a pump, 15 is a solution heat exchanger, 16 is a reheater, 17 is a first throttle valve, 18 is a separator, and 19 is a second throttle valve.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The core of the application is to provide a supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system, which comprises a supercritical carbon dioxide recompression circulation system and a double-effect absorption type power circulation system, wherein a circulation working medium in the double-effect absorption type power circulation system is a lithium bromide aqueous solution, and the saturation pressure of the lithium bromide aqueous solution can be obviously reduced by using a conventional cold source (such as environmental water) in the absorption and condensation process, so that the turbine backpressure in the double-effect absorption type power circulation system is reduced, the work capacity of a turbine is improved, and the double-effect absorption type power circulation can generate more work working media and higher low-pressure turbine inlet temperature compared with the single-effect absorption type power circulation, so that the work capacity of the turbine is improved, and the power generation efficiency of the combined power generation system is improved.
Referring to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of a supercritical carbon dioxide cycle and double-effect absorption type power cycle combined power generation system provided in the present application.
It should be noted that the working medium in the supercritical carbon dioxide recompression circulating system is carbon dioxide, which is an environmentally friendly, nontoxic, economical and chemically inert fluid, and it has very attractive physical and transmission characteristics near the critical point (31.3 ℃, 7.39MPa), and has the physical advantages of liquid and gas as power circulating working medium, i.e. high density, low viscosity, strong fluidity, excellent heat transfer performance, strong work capacity, etc. The supercritical carbon dioxide Brayton cycle utilizes the characteristics of high density, low viscosity and the like of carbon dioxide near a critical point to reduce the compression power consumption of the compressor, thereby improving the cycle efficiency. In addition, the critical temperature of carbon dioxide is close to the ambient temperature, which makes the temperature range of the heat source 1 applicable to the supercritical carbon dioxide power cycle very wide, such as coal-fired boiler, nuclear reactor, solar heat collector, fuel cell, geothermal heat, gas turbine exhaust and other industrial waste heat, etc., and the carbon dioxide power cycle can cool the carbon dioxide to the temperature near the critical point by using the conventional cooling working medium such as ambient water or air.
In order to utilize the special physical properties of carbon dioxide near the critical point, the carbon dioxide needs to release a large amount of low-grade heat in a heat sink before entering the compressor, which results in a large amount of heat
Figure BDA0002828192870000061
And (4) loss. In order to further optimize the power cycle of the supercritical carbon dioxide and improve the cycle efficiency, a waste heat recovery system is needed to recover the low-grade heat and convert the low-grade heat into mechanical energy to drive the generator to rotate, so that the power generation efficiency is improved. The supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system can better utilize a large amount of low-grade heat released in a heat sink before carbon dioxide enters the air compressor, the utilization rate of the heat is improved, and the power generation efficiency of the power generation system is further improved.
The specific embodiment provides a supercritical carbon dioxide cycle and double-effect absorption type power cycle combined power generation system, which comprises: the system comprises a supercritical carbon dioxide recompression circulation system and a double-effect absorption power circulation system, wherein the supercritical carbon dioxide recompression circulation system and the double-effect absorption power circulation system are coupled and connected through a generator 9, low-temperature waste heat of the supercritical carbon dioxide recompression circulation system is absorbed through a circulation working medium in the double-effect absorption power circulation system, and the circulation working medium is a lithium bromide aqueous solution; the generator 9 is used to separate the low concentration aqueous lithium bromide solution into water vapor and a first high concentration saturated aqueous lithium bromide solution.
In the operation process of the supercritical carbon dioxide cycle and double-effect absorption power cycle combined power generation system provided by the embodiment, the low-temperature waste heat of the supercritical carbon dioxide recompression cycle system can be utilized by the double-effect absorption power cycle system, the supercritical carbon dioxide recompression cycle system and the double-effect absorption power cycle system are coupled and connected through the generator 9, the carbon dioxide working medium in the supercritical carbon dioxide recompression cycle system enters the generator 9, the heat is transferred to the lithium bromide aqueous solution working medium in the double-effect absorption power cycle system, the lithium bromide aqueous solution absorbs heat and is heated to generate steam and a high-concentration lithium bromide aqueous solution, wherein the steam expands in the high-pressure turbine 10 to do work, and the high-concentration saturated lithium bromide aqueous solution further separates extra steam through the reheater 16, the first throttle valve 17 and the separator 18 in sequence, the partial steam is mixed with the expansion exhaust gas of the high-pressure turbine 10, absorbs heat through a reheater 16, is heated, and then is expanded in the low-pressure turbine 11 to do work, so that the output work of the absorption power cycle subsystem is improved.
Compared with the prior art, because the circulating working medium is the lithium bromide aqueous solution, the saturation pressure of the lithium bromide aqueous solution can be obviously reduced by using a conventional cold source (such as environmental water) in the absorption and condensation process, so that the back pressure of the turbine 10 and the turbine 11 in the double-effect absorption type power circulating system is reduced, and the work capacity of the turbine 10 and the turbine 11 is improved. Compared with the single-effect absorption power cycle, the double-effect absorption power cycle can generate more work working media and higher inlet temperature of the low-pressure turbine 11, and the work doing capability of the turbine is improved, so that the power generation efficiency of the combined power generation system is improved.
It should be noted that, the high pressure turbine 10 and the low pressure turbine 11 are both connected to the first generator 12, and the high pressure turbine 10, the low pressure turbine 11 and the first generator 12 are coaxially connected, and in the use process, the high pressure turbine 10 and the low pressure turbine 11 transmit mechanical energy to the first generator 12, and the first generator 12 converts the mechanical energy into electric energy.
When the carbon dioxide working medium in the supercritical carbon dioxide recompression circulating system flows through the generator 9, the low-temperature waste heat is transferred to the lithium bromide aqueous solution in the generator 9, so that part of heat of the supercritical carbon dioxide is utilized, and the cold source loss of the supercritical carbon dioxide power circulating system is reduced.
The double-effect absorption power cycle system also comprises a first throttling valve 17 for throttling and depressurizing the first high-concentration saturated lithium bromide aqueous solution and a separator 18 connected with an outlet of the first throttling valve 17;
the separator 18 is for separating the first high-concentration saturated lithium bromide aqueous solution after being throttled and depressurized by the first throttle valve 17 into water vapor and a second high-concentration saturated lithium bromide aqueous solution; and the concentration of the second high concentration saturated aqueous lithium bromide solution is greater than the concentration of the first high concentration saturated aqueous lithium bromide solution.
In the using process, the aqueous lithium bromide solution is separated only once in the prior art, while in the working process of the supercritical carbon dioxide cycle and double-effect absorption type power cycle combined power generation system in the embodiment, after the aqueous lithium bromide solution separates out water vapor and the first high-concentration saturated aqueous lithium bromide solution in the generator 9, the first high-concentration saturated aqueous lithium bromide solution is depressurized after flowing through the first throttle valve 17, the saturation concentration of the first high-concentration saturated aqueous lithium bromide solution after depressurization is further increased, the first high-concentration saturated aqueous lithium bromide solution is separated into water vapor and the second high-concentration saturated aqueous lithium bromide solution again in the separator 18, and the concentration of the second high-concentration saturated aqueous lithium bromide solution is greater than that of the first high-concentration saturated aqueous lithium bromide solution at this time.
Compared with the prior art, the secondary separation device can extract more water vapor, so that extra steam for doing work is generated, the work efficiency is improved, and the power generation efficiency of the power generation system is further improved.
The double-effect absorption type power cycle system can also comprise a high-pressure turbine 10 and a low-pressure turbine 11, and a water vapor outlet of the generator 9 is connected with an inlet of the high-pressure turbine 10 so as to expand water vapor separated from the generator 9 in the high-pressure turbine 10 to work; the water vapor separated by the separator 18 and the water vapor expanded and worked in the high pressure turbine 10 enter the low pressure turbine 11 for further expansion and work.
Compared with the prior art, the arrangement of the low-pressure turbine 11 and the high-pressure turbine 10 can enable the turbines to generate more output work, and the power generation efficiency of the power generation system is improved.
In addition, the double-effect absorption power cycle system further comprises a reheater 16, a hot-side fluid inlet of the reheater 16 is connected with a solution outlet of the generator 9, and a hot-side fluid outlet of the reheater 16 is connected with an inlet of the first throttling valve 17;
the cold side fluid inlet of reheater 16 is connected to both the steam outlet of separator 18 and the outlet of high pressure turbine 10; the cold-side fluid outlet of reheater 16 is connected to the inlet of low-pressure turbine 11.
In the using process, the water vapor separated by the separator 18 and the water vapor expanded and worked by the high-pressure turbine 10 are converged, the converged water vapor enters the reheater 16 and then absorbs the heat of the lithium bromide aqueous solution flowing into the reheater 16 from the generator 9, the heated water vapor enters the low-pressure turbine 11 to be further expanded and worked, the heat of the first high-concentration saturated lithium bromide aqueous solution can be further absorbed and utilized, the heat utilization rate is improved, the output work of the low-pressure turbine 11 is improved, and the power generation efficiency of the combined power generation system is further improved.
As shown in fig. 1, in another embodiment, the supercritical carbon dioxide recompression cycle system comprises a heat source 1, a turbine 2, a second generator 3, a high temperature regenerator 4, a low temperature regenerator 5, a cooler 6, a main compressor 7 and a recompressor 8; the double-effect absorption power cycle system comprises a generator 9, a high-pressure turbine 10, a low-pressure turbine 11, a first generator 12, an absorber 13, a pump 14, a solution heat exchanger 15, a reheater 16, a first throttling valve 17, a separator 18 and a second throttling valve 19.
In fig. 1, a cold side fluid outlet of a high temperature regenerator 4 in a supercritical carbon dioxide recompression circulating system is connected to an inlet of a heat source 1, an outlet of the heat source 1 is connected to an inlet of a turbine 2, an outlet of the turbine 2 is connected to a hot side fluid inlet of the high temperature regenerator 4, a hot side fluid outlet of the high temperature regenerator 4 is connected to a hot side fluid inlet of a low temperature regenerator 5, a hot side fluid outlet of the low temperature regenerator 5 is connected to an inlet of a recompressor 8 and a hot side fluid inlet of a generator 9, a hot side fluid outlet of the generator 9 is connected to a hot side fluid inlet of a cooler 6, a hot side fluid outlet of the cooler 6 is connected to an inlet of a main compressor 7, an outlet of the main compressor 7 is connected to a cold side fluid inlet of the low temperature regenerator 5, a cold side fluid outlet of the low temperature regenerator 5 is connected to an outlet of the recompressor 8 and a cold side fluid, to form a loop.
The solution outlet of a generator 9 in the double-effect absorption type power cycle system is connected with the hot side fluid inlet of a reheater 16, the hot side fluid outlet of the reheater 16 is connected with the inlet of a first throttling valve 17, the outlet of the first throttling valve 17 is connected with the inlet of a separator 18, the solution outlet of the separator 18 is connected with the hot side fluid inlet of a solution heat exchanger 15, the steam outlet of the separator 18 is connected with the outlet of a high-pressure turbine 10 and the cold side fluid inlet of the reheater 16, the cold side fluid outlet of the reheater 16 is connected with the inlet of a low-pressure turbine 11, the outlet of the low-pressure turbine 11 is connected with the steam inlet of an absorber 13, the solution outlet of the absorber 13 is connected with the inlet of a pump 14, the outlet of the pump 14 is connected with the cold side fluid inlet of the solution heat exchanger 15, the cold side fluid outlet of the solution heat exchanger 15 is connected with the, the hot side fluid outlet of the solution heat exchanger 15 is connected to the inlet of a second throttling valve 19, and the outlet of the second throttling valve 19 is connected to the solution inlet of the absorber 13.
The heat source 1 in the supercritical carbon dioxide recompression circulating system may be a nuclear reactor of a nuclear power plant, a boiler of a coal-fired power plant, a heat collector of a solar power plant, a geothermal power plant, or a gas turbine exhaust of a gas turbine combined power generation system.
In the supercritical carbon dioxide recompression circulating system, the circulating process is as follows:
the temperature of the carbon dioxide working medium is further increased after the heat is absorbed by the heat source 1, and the high-temperature and high-pressure carbon dioxide working medium output from the outlet of the heat source 1 enters the turbine 2 and expands in the turbine 2 to do work so as to convert the heat energy of the supercritical carbon dioxide into the mechanical energy of the turbine 2 rotating at a high speed; the turbine 2 may be coaxially connected to the main compressor 7, the recompressor 8 and the second generator 3, or the turbine 2 may be divided into two stages by a split-shaft arrangement, in which one stage of the turbine is coaxially connected to the main compressor 7 and the recompressor 8, and the other stage of the turbine is coaxially connected to the generator 3 for the power turbine. One part of mechanical energy generated by the turbine 2 is transmitted to the main compressor 7 and the recompressor 8 for compressing carbon dioxide working medium, and the other part of mechanical energy is transmitted to the second generator 3 for driving the second generator 3 to rotate so as to convert the mechanical energy into electric energy; the carbon dioxide working medium expanded by the turbine 2 sequentially flows through the high-temperature heat regenerator 4 and the low-temperature heat regenerator 5 and releases heat in the two heat regenerators, and the part of heat is used for preheating the compressed supercritical carbon dioxide working medium; the carbon dioxide working medium at the hot side fluid outlet of the low-temperature heat regenerator 5 is divided into two paths, wherein one path releases heat in the generator 9 and the cooler 6 in sequence to reduce the temperature of the generator to be close to the critical point of the carbon dioxide, so that the power consumption of the main compressor 7 for compressing the carbon dioxide is reduced by utilizing the special physical properties of the carbon dioxide close to the critical point; the carbon dioxide working medium compressed and boosted by the main compressor 7 flows through the low-temperature heat regenerator 5 to absorb heat and raise temperature, and is converged with the other path of carbon dioxide compressed and boosted by the secondary compressor 8. The mixed carbon dioxide working medium flows through the high-temperature heat regenerator 4 to continuously absorb heat and raise temperature, and finally flows back to the heat source 1, so that a complete supercritical carbon dioxide recompression power cycle is completed.
In the double-effect absorption power cycle system, the cycle process is as follows:
the low-concentration lithium bromide aqueous solution entering the generator 9 absorbs heat released when the supercritical carbon dioxide flows through the generator 9, and the saturated solubility of the lithium bromide aqueous solution is increased due to the temperature rise of the lithium bromide aqueous solution, so that water vapor and the first high-concentration saturated lithium bromide aqueous solution are separated; the high-temperature and high-pressure steam separated from the generator 9 enters the high-pressure turbine 10 and is expanded in the high-pressure turbine 10 to do work, so that the heat energy of the steam is converted into the mechanical energy of the high-pressure turbine 10; meanwhile, the high-temperature and high-pressure first high-concentration saturated lithium bromide aqueous solution flowing out of the generator 9 flows through the reheater 16 to release heat, and then flows through the first throttle valve 17; the saturated solubility of the lithium bromide aqueous solution throttled and depressurized by the first throttle valve 17 is further increased, and more water vapor and a second high-concentration saturated lithium bromide aqueous solution with higher concentration are further separated after entering the separator 18; the water vapor leaving the separator 18 is merged with the water vapor expanded and worked in the high-pressure turbine 10 and enters a reheater 16 to absorb the heat of the high-temperature lithium bromide water solution flowing out of the generator 9; the reheated and heated steam enters the low-pressure turbine 11 to further expand and work, and the heat energy of the steam is converted into the mechanical energy of the low-pressure turbine 11; the high-pressure turbine 10 is coaxially connected with the low-pressure turbine 11 and the first generator 12, and mechanical energy generated by the high-pressure turbine 10 and the low-pressure turbine 11 is transmitted to the first generator 12 so that the first generator 12 rotates to convert the mechanical energy into electric energy; the second high concentration saturated aqueous lithium bromide solution leaving the separator 18 passes through the solution heat exchanger 15 to release heat and then through the second throttling valve 19; the lithium bromide aqueous solution throttled and depressurized by the second throttle valve 19 enters an absorber 13 to absorb the water vapor expanded and worked by the low-pressure turbine 11 and release heat, so that a low-concentration saturated lithium bromide aqueous solution is formed; then the lithium bromide aqueous solution leaving the absorber 13 flows through the pump 14 and is compressed by the pump 14, the pressurized lithium bromide aqueous solution absorbs heat through the solution heat exchanger 15 and is heated up, and finally flows back to the generator 9, thereby completing a complete double-effect absorption power cycle.
The heat source of the double-effect absorption type power cycle system is the waste heat of the supercritical carbon dioxide recompression cycle, and the power generation efficiency of the combined power generation system is improved by recycling and utilizing the part of low-grade heat source. In addition, compared with other waste heat recycling systems, the double-effect absorption type power cycle can more fully recycle the low-temperature waste heat of the supercritical carbon dioxide power cycle, thereby reducing the cold source loss of the power cycle, generating more output power and further improving the power generation efficiency of the combined power generation system.
Through theoretical practice and calculation, the combined power generation system provided by the application can be used for compressing the circulating energy relative to the supercritical carbon dioxide
Figure BDA0002828192870000111
The efficiency is improved by 11.51 percent, and compared with a combined system integrating a supercritical carbon dioxide recompression cycle and a single-effect absorption type power cycle, the combined system can improve the efficiency
Figure BDA0002828192870000112
The efficiency is further improved by 3.61%.
In addition, the supercritical carbon dioxide recompression circulating system has few components, small size and compact structure, and the double-effect absorption power circulating system has few components, simple structure and lower initial investment and operation and maintenance cost of the combined power generation system, so that the unit power generation cost of the whole combined power generation system is lower, and better economic performance is shown. Through practice and theoretical calculation, the unit cost of the combined system provided by the application can be reduced by 8.37% compared with that of a supercritical carbon dioxide recompression cycle, and the unit cost of the combined system can be further reduced by 3.15% compared with that of a combined power generation system integrating the supercritical carbon dioxide recompression cycle and a single-effect absorption type power cycle.
It should be noted that the first generator 12 and the second generator 3, and the first throttle 17 and the second throttle 19 mentioned in the present document are only for limiting the difference of the positions, and are not in sequence.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. Any combination of all embodiments provided by the present application is within the scope of the present invention, and is not described herein.
The supercritical carbon dioxide cycle and double-effect absorption power cycle combined power generation system provided by the application is described in detail above. The principles and embodiments of the present application are explained herein using specific examples, which are provided only to help understand the method and the core idea of the present application. It should be noted that, for those skilled in the art, it is possible to make several improvements and modifications to the present application without departing from the principle of the present application, and such improvements and modifications also fall within the scope of the claims of the present application.

Claims (9)

1. A supercritical carbon dioxide cycle and double-effect absorption power cycle combined power generation system is characterized by comprising: the system comprises a supercritical carbon dioxide recompression circulation system and a double-effect absorption type power circulation system, wherein the supercritical carbon dioxide recompression circulation system and the double-effect absorption type power circulation system are coupled and connected through a generator (9), low-temperature waste heat of the supercritical carbon dioxide recompression circulation system is absorbed through a circulation working medium in the double-effect absorption type power circulation system, and the circulation working medium is a lithium bromide aqueous solution;
the generator (9) is used for separating the low-concentration lithium bromide aqueous solution into water vapor and a first high-concentration saturated lithium bromide aqueous solution.
2. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to claim 1, wherein the double-effect absorption power cycle system further comprises a first throttling valve (17) for throttling and depressurizing the first high concentration saturated aqueous lithium bromide solution and a separator (18) connected to an outlet of the first throttling valve (17);
the separator (18) is used for separating the first high-concentration saturated lithium bromide aqueous solution after being throttled and depressurized by the first throttle valve (17) into water vapor and a second high-concentration saturated lithium bromide aqueous solution; and the concentration of the second high-concentration saturated lithium bromide aqueous solution is greater than that of the first high-concentration saturated lithium bromide aqueous solution.
3. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to claim 2, wherein the double-effect absorption power cycle system further comprises a high pressure turbine (10) and a low pressure turbine (11), and the steam outlet of the generator (9) is connected with the inlet of the high pressure turbine (10) so that the steam separated from the generator (9) is expanded in the high pressure turbine (10) to produce work;
the water vapor separated by the separator (18) and the water vapor expanded and worked in the high-pressure turbine (10) enter the low-pressure turbine (11) for further expansion and work.
4. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to claim 3, wherein the double-effect absorption power cycle system further comprises a first generator (12) coaxially connected to both the high pressure turbine (10) and the low pressure turbine (11), the high pressure turbine (10) and the low pressure turbine (11) each transferring mechanical energy to the first generator (12), the first generator (12) converting mechanical energy to electrical energy.
5. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to claim 3, wherein the double-effect absorption power cycle system further comprises a reheater (16), wherein a hot-side fluid inlet of the reheater (16) is connected with the solution outlet of the generator (9), and a hot-side fluid outlet of the reheater (16) is connected with the inlet of the first throttling valve (17);
the steam outlet of the separator (18) and the outlet of the high-pressure turbine (10) are both connected to the cold-side fluid inlet of the reheater (16); the cold-side fluid outlet of the reheater (16) is connected to the inlet of the low-pressure turbine (11).
6. The supercritical carbon dioxide cycle and double-effect absorption power cycle combined power generation system according to claim 5, wherein the double-effect absorption power cycle system further comprises a solution heat exchanger (15), a second throttling valve (19), an absorber (13), and a pump (14); the solution outlet of the separator (18) is connected to the hot side fluid inlet of the solution heat exchanger (15), the hot side fluid outlet of the solution heat exchanger (15) is connected to the inlet of the second throttle valve (19), the outlet of the second throttle valve (19) is connected to the solution inlet of the absorber (13), the outlet of the low pressure turbine (11) is connected to the water vapor inlet of the absorber (13), the solution outlet of the absorber (13) is connected to the inlet of the pump (14), and the outlet of the pump (14) is connected to the cold side fluid inlet of the solution heat exchanger (15).
7. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to any of claims 1-6, wherein the supercritical carbon dioxide recompression cycle system comprises a heat source (1), a high temperature regenerator (4), a low temperature regenerator (5), a primary compressor (7), a cooler (6), a recompressor (8), a turbine (2), and a second generator (3);
the cold side fluid outlet of the high-temperature regenerator (4) is connected with the inlet of the heat source (1), the outlet of the heat source (1) is connected with the inlet of the turbine (2), the outlet of the turbine (2) is connected with the hot side fluid inlet of the high-temperature regenerator (4), the hot side fluid outlet of the high-temperature regenerator (4) is connected with the hot side fluid inlet of the low-temperature regenerator (5), the inlet of the recompressor (8) and the hot side fluid inlet of the generator (9) are both connected with the hot side fluid outlet of the low-temperature regenerator (5), the hot side fluid outlet of the generator (9) is connected with the hot side fluid inlet of the cooler (6), the hot side fluid outlet of the cooler (6) is connected with the inlet of the main compressor (7), and the outlet of the main compressor (7) is connected with the cold side fluid inlet of the low-temperature regenerator (5), the outlet of the recompressor (8) and the cold side fluid inlet of the high-temperature regenerator (4) are both connected with the cold side fluid outlet of the low-temperature regenerator (5).
8. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to claim 7, wherein the turbine (2), the main compressor (7), the recompressor (8) and the second generator (3) are all coaxially arranged;
or the turbine (2) comprises two stages, wherein one stage of turbine is coaxially connected with the main compressor (7) and the secondary compressor (8), the other stage of turbine is a power turbine, and the power turbine is coaxially connected with the second generator (3).
9. The combined supercritical carbon dioxide cycle and double-effect absorption power cycle power generation system according to claim 7, where the heat source (1) is a nuclear reactor of a nuclear power plant, or a boiler of a coal-fired power plant, or a heat collector of a solar power plant, or a geothermal source of a geothermal power plant, or a gas turbine tail gas of a gas turbine combined power generation system.
CN202011434998.8A 2020-12-10 2020-12-10 Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system Pending CN112483207A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011434998.8A CN112483207A (en) 2020-12-10 2020-12-10 Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011434998.8A CN112483207A (en) 2020-12-10 2020-12-10 Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system

Publications (1)

Publication Number Publication Date
CN112483207A true CN112483207A (en) 2021-03-12

Family

ID=74940925

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011434998.8A Pending CN112483207A (en) 2020-12-10 2020-12-10 Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system

Country Status (1)

Country Link
CN (1) CN112483207A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112880230A (en) * 2021-04-29 2021-06-01 湖南大学 Power generation and refrigeration combined system
CN113251462A (en) * 2021-05-14 2021-08-13 西安交通大学 Combined cooling, heating and power system and method for coupling Brayton cycle and absorption refrigeration cycle
WO2023024962A1 (en) * 2021-08-26 2023-03-02 比亚迪股份有限公司 Supercritical carbon dioxide cycle based power generation-brine lithium extraction coupling system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104481613A (en) * 2014-11-26 2015-04-01 湖南大学 Power generation system of double-drive generator for reheating cycle utilization of low-grade heat energy
CN108643981A (en) * 2018-04-09 2018-10-12 西安交通大学 A kind of low-grade heat source driving non-azeotropic mixed working medium cogeneration system and method
CN108661732A (en) * 2018-05-10 2018-10-16 西安热工研究院有限公司 A kind of liquefied natural gas (LNG) production system of combustion gas-supercritical carbon dioxide combined power
CN110344898A (en) * 2019-08-05 2019-10-18 上海发电设备成套设计研究院有限责任公司 Absorption type desalination and closed cycle electricity generation system
CN111852600A (en) * 2019-04-30 2020-10-30 中国船舶重工集团公司第七一一研究所 Cascade type diesel engine waste heat recovery cogeneration system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104481613A (en) * 2014-11-26 2015-04-01 湖南大学 Power generation system of double-drive generator for reheating cycle utilization of low-grade heat energy
CN108643981A (en) * 2018-04-09 2018-10-12 西安交通大学 A kind of low-grade heat source driving non-azeotropic mixed working medium cogeneration system and method
CN108661732A (en) * 2018-05-10 2018-10-16 西安热工研究院有限公司 A kind of liquefied natural gas (LNG) production system of combustion gas-supercritical carbon dioxide combined power
CN111852600A (en) * 2019-04-30 2020-10-30 中国船舶重工集团公司第七一一研究所 Cascade type diesel engine waste heat recovery cogeneration system
CN110344898A (en) * 2019-08-05 2019-10-18 上海发电设备成套设计研究院有限责任公司 Absorption type desalination and closed cycle electricity generation system

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
FENG ZHANG , GAOLIANG LIAO, JIAQIANG E, JINGWEI CHEN, ERWEI LENG: "Comparative study on the thermodynamic and economic performance of novel absorption power cycles driven by the waste heat from a supercritical CO2 cycle", 《ENERGY CONVERSION AND MANAGEMENT》 *
TOWHID PARIKHANI, HADI GHAEBI, HADI ROSTAMZADEH: "A novel geothermal combined cooling and power cycle based on the absorption power cycle: Energy, exergy and exergoeconomic analysis", 《ENERGY》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112880230A (en) * 2021-04-29 2021-06-01 湖南大学 Power generation and refrigeration combined system
CN112880230B (en) * 2021-04-29 2021-07-02 湖南大学 Power generation and refrigeration combined system
CN113251462A (en) * 2021-05-14 2021-08-13 西安交通大学 Combined cooling, heating and power system and method for coupling Brayton cycle and absorption refrigeration cycle
WO2023024962A1 (en) * 2021-08-26 2023-03-02 比亚迪股份有限公司 Supercritical carbon dioxide cycle based power generation-brine lithium extraction coupling system

Similar Documents

Publication Publication Date Title
CN107630726B (en) Multi-energy hybrid power generation system and method based on supercritical carbon dioxide circulation
CN108868930B (en) Supercritical/transcritical carbon dioxide combined cycle power generation system utilizing waste heat of internal combustion engine
CN112483207A (en) Supercritical carbon dioxide circulation and double-effect absorption type power circulation combined power generation system
JP3230516U (en) Supercritical carbon dioxide Brayton cycle power generation system for waste heat recovery
JP2018514686A (en) Hybrid power generation system using supercritical carbon dioxide cycle
CN108005744B (en) Supercritical CO 2 Circulating machine furnace cold energy recovery and power generation integrated heat supply method
CN107131016B (en) Supercritical CO2Coal-fired thermal power generation system combined with organic Rankine cycle
CN111365131B (en) Power-cooling combined supply system driven by exhaust smoke waste heat of gas turbine and method thereof
CN109519243B (en) Supercritical CO2 and ammonia water combined cycle system and power generation system
CN112554983A (en) Liquid carbon dioxide energy storage system and method coupled with kalina cycle
CN213928479U (en) Liquid carbon dioxide energy storage system coupled with kalina circulation
CN111735237B (en) Well low temperature heat utilization merit cold joint system
CN113153462A (en) Waste heat auxiliary heating condensed water system and method for supercritical carbon dioxide circulation cold end
CN114198173B (en) Electric cooling combined supply system integrating full-regenerative brayton cycle and absorption refrigeration
CN214741510U (en) Waste heat auxiliary heating condensate system for supercritical carbon dioxide circulation cold end
CN114135398A (en) Gas turbine combined cycle power generation system and method under distributed energy environment
CN113153475A (en) Power-heat complementary supercritical CO2Power cycle power generation system
CN111271898B (en) Combined cooling heating and power system based on geothermal energy and working method thereof
CN111306835B (en) Ammonia water working medium combined cooling heating and power system utilizing medium-low temperature heat source and working method thereof
CN210317415U (en) Absorption type seawater desalination and closed cycle power generation system
CN112880230B (en) Power generation and refrigeration combined system
CN111486067A (en) Based on sCO2Brayton cycle geothermal-solar power generation system
CN110541737A (en) medium-low temperature waste heat power generation system utilizing LNG cold energy and working method thereof
CN216347193U (en) Device for improving running back pressure of air cooling unit
CN112459858B (en) Chemical looping combustion coupled supercritical CO2Cyclic cogeneration system

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
RJ01 Rejection of invention patent application after publication

Application publication date: 20210312

RJ01 Rejection of invention patent application after publication