CN108798812B - Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation - Google Patents
Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation Download PDFInfo
- Publication number
- CN108798812B CN108798812B CN201810934630.4A CN201810934630A CN108798812B CN 108798812 B CN108798812 B CN 108798812B CN 201810934630 A CN201810934630 A CN 201810934630A CN 108798812 B CN108798812 B CN 108798812B
- Authority
- CN
- China
- Prior art keywords
- temperature
- water
- working medium
- rankine cycle
- waste heat
- 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
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K27/00—Plants for converting heat or fluid energy into mechanical energy, not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
- F01C13/00—Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D15/00—Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
- F01D15/10—Adaptations for driving, or combinations with, electric generators
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K25/00—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
- F01K25/08—Plants 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
- F01K25/10—Plants 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
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B1/00—Methods of steam generation characterised by form of heating method
- F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
Abstract
The invention relates to an industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation. The system comprises a waste heat recovery and heat storage loop, a primary steam Rankine cycle power generation loop and a secondary organic Rankine cycle power generation loop; when the waste heat medium is in operation, the temperature of the waste heat medium is 150-400 ℃, and the waste heat medium is one of medium and low temperature waste heat flue gas, waste heat steam and waste water. When the system is in a normal working mode, the water working medium absorbs heat in the waste heat medium, and the water working medium after absorbing heat can be in a liquid state, a gas state or a gas-liquid state. The higher the temperature of the waste heat medium, the higher the dryness after the water working medium absorbs heat, wherein the generated steam has a higher grade, the heat is converted into work through the cascade Rankine cycle, the lower the grade of the liquid water, and the heat is converted into work through the secondary organic Rankine cycle. The technical scheme of the invention can ensure the stability of power generation of the system and efficiently utilize industrial waste heat.
Description
Technical Field
The invention belongs to the technical field of industrial waste heat recovery power generation, and particularly relates to an industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation.
Background
The middle-low temperature waste heat in the industrial waste heat of China is about half of the total waste heat, and a large amount of energy sources are hopefully saved, carbon dioxide emission is reduced, heat pollution is reduced, and the ecological environment is improved by utilizing the middle-low temperature waste heat. A significant feature of industrial waste heat is the unsteadiness of the heat load, which is determined by the process. For example: 1. for the waste heat steam generated in the steelmaking industry, the waste heat steam generation amount and the diffusing period change along with the production change, and the waste heat steam has certain fluctuation, so that the diffusing steam has strong intermittence and discontinuity [ reference: dai Haibo low pressure bleed steam recovery power generation technology metallurgical power 2015, 5:63-67. 2. For the sintering waste heat of the steel plant, the equipment is not stable to operate in the sintering production, the short-time shutdown is difficult to avoid, and the interruption of the sintering mineral flow is a frequent condition, so that the continuity of the sintering waste heat source is difficult to ensure. In addition, because of the difference of sintering material gas permeability and the reasons such as auxiliary material inequality, cause the resistance change of sintering flue gas system great, finally lead to the flue gas volume to change greatly, the range can reach more than 40% [ reference: li Baodong, li Pengyuan, du Meng. Analysis of the status of sintering waste heat power generation and problems, metallurgical energy source, 2012, 31 (3): 49-52 ].3. For the waste heat of waste gas in cement production, the temperature of the waste gas discharged from a clinker cooler is between 250 and 450 ℃, and the fluctuation is larger [ reference: the method mainly comprises the steps of debugging, installing, 2013, 2:24-26 of a pure low-temperature cement waste heat power generation system.
Organic rankine cycle (organic Rankine cycle, ORC) power generation technology is one of the effective means of medium-low temperature waste heat utilization. The circulating working medium is an organic fluid and has the thermodynamic characteristics of low boiling point and high saturated steam pressure. Compared with a steam Rankine cycle taking water as a working medium, the organic Rankine cycle has better thermodynamic performance and stability under the heat source with the waste heat temperature of less than 300 ℃ such as flue gas and the like. However, instability of the medium-low temperature waste heat presents a significant challenge to the organic rankine cycle technology. When the expander deviates seriously from the design condition or is started and stopped frequently, the efficiency is reduced sharply, and great mechanical damage is caused. At present, there are mainly the following solutions, namely, organic rankine cycle with heat recovery, organic rankine cycle with oil path, fan-assisted organic rankine cycle, double-tank heat storage organic rankine cycle, single-tank heat storage organic rankine cycle, and phase-change heat storage organic rankine cycle [ reference: roberto Pili, alessandro Romagnoli, hartmut Spliethoff, christoph Wieland. Techno-Economic Analysis of Waste Heat Recovery with ORC from Fluctuating Industrial sources, energy processes, 2017, 129:503-510.
The invention aims to provide an innovative scheme of cascade Rankine cycle and two-stage water heat accumulation based on water vapor-organic working medium, which is used for solving the problem of instability of medium-low temperature waste heat utilization and realizing high-efficiency and low-cost utilization of a heat source.
Disclosure of Invention
In order to solve the adverse effect of industrial waste heat load fluctuation on an industrial waste heat recovery power generation system, the invention provides an industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation.
The industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation comprises a waste heat recovery heat accumulation loop, a primary steam Rankine cycle power generation loop and a secondary organic Rankine cycle power generation loop;
the waste heat recovery and heat storage loop comprises an evaporator 1, a first preheater 2, a second preheater 4, a high-temperature heat storage water tank 6, a low-temperature heat storage water tank 7 and a low-temperature water pump 13;
the primary steam Rankine cycle power generation loop comprises an evaporator 1, an intermediate heat exchanger 3, a high-temperature heat storage water tank 6, a steam screw expander 8, a first power generator 10 and a medium-temperature water pump 12; the evaporator 1, the high-temperature heat storage water tank 6, the steam screw expander 8, the intermediate heat exchanger 3 and the intermediate-temperature water pump 12 are connected in series to form a primary hydraulic medium loop;
the secondary organic Rankine cycle power generation loop comprises an intermediate heat exchanger 3, a second preheater 4, a condenser 5, an organic working medium turbine 9, a second generator 11 and an organic working medium pump 14; wherein the second preheater 4, the intermediate heat exchanger 3, the organic working medium turbine 9, the condenser 5 and the organic working medium pump 14 are connected in series to form a secondary organic working medium loop;
one side of the evaporator 1 and one side of the first preheater 2 are waste heat mediums, and the other side of the evaporator 1 and the other side of the first preheater 2 are hydraulic mediums;
one side of the intermediate heat exchanger 3 and one side of the second preheater 4 are water working media, the other side of the intermediate heat exchanger 3 and the other side of the second preheater 4 are organic working media, the intermediate heat exchanger 3 on one side of the water working media is connected in series in the primary steam Rankine cycle power generation loop, the second preheater 4 on one side of the water working media is connected in series in the waste heat recovery heat storage loop, and the intermediate heat exchanger 3 on one side of the organic working media and the second preheater 4 are connected in series in the secondary organic Rankine cycle power generation loop;
one side of the condenser 5 is a cooling water working medium, the other side of the condenser 5 is an organic working medium, and the condenser 5 on one side of the organic working medium is connected in series in a secondary organic Rankine cycle power generation loop;
the water working medium outlet of the evaporator 1 is communicated with the upper inlet of the high-temperature heat storage water tank 6, the upper outlet of the high-temperature heat storage water tank 6 is communicated with the inlet of the steam screw expander 8 through the high-temperature steam valve 15, the outlet of the steam screw expander 8 is communicated with the water working medium inlet of the intermediate heat exchanger 3 through the intermediate-temperature steam valve 16, and the water working medium outlet of the intermediate heat exchanger 3 is communicated with the water working medium inlet of the evaporator 1 through the first heat exchange water valve 17, the intermediate-temperature water pump 12 and the first intermediate-temperature water valve 18;
the bottom outlet of the high-temperature heat storage water tank 6 is divided into two paths through a first high-temperature water valve 19 and a second high-temperature water valve 23, one path is communicated with the water working medium inlet of the second preheater 4, the other path is communicated with the water working medium inlet of the intermediate heat exchanger 3, the water working medium outlet of the intermediate heat exchanger 3 is communicated with the water working medium inlet of the second preheater 4 through a second heat exchange water valve 24, the water working medium outlet of the second preheater 4 is communicated with the inlet of the low-temperature heat storage water tank 7 through a throttle valve 20, the outlet of the low-temperature heat storage water tank 7 is communicated with the water working medium inlet of the first preheater 2 through a low-temperature water valve 21 and a low-temperature water pump 13, and the water working medium outlet of the first preheater 2 is communicated with the water working medium inlet of the evaporator 1 through a second medium-temperature water valve 22;
the organic working medium outlet of the intermediate heat exchanger 3 is communicated with the inlet of the organic working medium turbine 9, the outlet of the organic working medium turbine 9 is communicated with the organic working medium inlet of the condenser 5, the organic working medium outlet of the condenser 5 is communicated with the organic working medium inlet of the second preheater 4 through the organic working medium pump 14, and the organic working medium outlet of the second preheater 4 is communicated with the organic working medium inlet of the intermediate heat exchanger 3;
when the system works, the temperature of the waste heat medium is 150-400 ℃, and when enough waste heat can be utilized, the system simultaneously performs heat accumulation and cascade Rankine cycle power generation modes; when the waste heat load severely fluctuates, the system utilizes the stored high-temperature water to carry out a single-stage organic Rankine cycle power generation mode.
The further defined technical scheme is as follows:
the waste heat medium is one of medium and low temperature waste heat flue gas, waste heat steam and waste water.
The working temperature of the high-temperature heat storage water tank 6 is 150-300 ℃, and the working temperature of the low-temperature heat storage water tank 7 is 30-150 ℃.
The high-temperature steam valve 15, the medium-temperature steam valve 16, the first heat exchange water valve 17, the first medium-temperature water valve 18, the first high-temperature water valve 19, the low-temperature water valve 21, the second medium-temperature water valve 22, the second high-temperature water valve 23 and the second heat exchange water valve 24 are all ball valves.
The throttle valve 20 is a sliding sleeve type throttle valve.
The beneficial technical effects of the invention are as follows:
1. the system of the invention has a unique working principle. In the existing cascade Rankine cycle technical scheme, the heat of the bottom cycle is all from the residual heat of the condensing end of the top cycle. In the technical scheme of the invention, when the system is in a normal working mode, liquid water of the high-temperature heat storage water tank 6 flows into the low-temperature heat storage water tank 7 through the second preheater 4, and the working medium of the bottom organic Rankine cycle firstly absorbs heat through the second preheater 4 and is partially evaporated; heat is then further extracted from the condensing end of the overhead vapor rankine cycle (i.e., intermediate heat exchanger 3) and fully vaporized. The condensing end waste heat of the top cycle only provides part of the heat source of the bottom organic rankine cycle.
2. The invention organically combines the grade of waste heat and thermodynamic cycle. When the system is in a normal operation mode, the water working medium of the overhead steam Rankine cycle absorbs heat from the evaporator 1, and the state of the water working medium outlet side of the evaporator 1 can be liquid, gas or gas-liquid two-phase. The higher the inlet temperature of the industrial waste heat medium, the greater the amount of steam produced by the system. The energy grade of the gaseous steam of the high-temperature heat storage water tank 6 is relatively high, and the high-temperature heat storage water tank is suitable for driving cascade Rankine cycle power generation. The energy grade of the liquid water in the high-temperature heat storage water tank 6 is relatively low, and the liquid water is suitable for driving the bottom organic Rankine cycle to generate power. Therefore, the waste heat grade is automatically matched with the thermodynamic process, and the operation is optimized.
3. The high-temperature heat storage water tank 6 and the low-temperature heat storage water tank 7 in the system ensure the stability of heat power conversion and solve the problem of instability of medium-low temperature waste heat utilization. When the system is in a normal working mode, if the steam quantity generated at the water working medium outlet side of the evaporator 1 is larger than the flow quantity of the overhead steam screw expander 8, part of steam in the high-temperature heat storage water tank 6 is condensed; if the amount of steam generated at the water working medium outlet side of the evaporator 1 is smaller than the flow rate of the overhead vapor screw expander 8, part of the liquid water in the high-temperature heat storage water tank 6 will be evaporated. Because the high-temperature heat storage water tank 6 has a certain capacity, the problem of unstable power generation caused by fluctuation of industrial waste heat can be effectively relieved.
Drawings
FIG. 1 is a schematic diagram of a system according to the present invention.
FIG. 2 is a schematic diagram of the normal operation mode of the system of the present invention.
FIG. 3 is a schematic diagram of a thermal storage power generation mode of the system of the present invention.
Number in the upper diagram: the evaporator 1, the first preheater 2, the intermediate heat exchanger 3, the second preheater 4, the condenser 5, the high-temperature heat storage water tank 6, the low-temperature heat storage water tank 7, the steam screw expander 8, the organic working medium turbine 9, the first generator 10, the second generator 11, the medium-temperature water pump 12, the low-temperature water pump 13, the organic working medium pump 14, the high-temperature steam valve 15, the medium-temperature steam valve 16, the first heat exchange water valve 17, the first medium-temperature water valve 18, the first high-temperature water valve 19, the throttle valve 20, the low-temperature water valve 21, the second medium-temperature water valve 22, the second high-temperature water valve 23 and the second heat exchange water valve 24.
Detailed Description
The invention is further described by way of examples with reference to the accompanying drawings.
Examples
Referring to fig. 1, an industrial waste heat recovery power generation system based on cascade rankine cycle and two-stage water heat storage includes a waste heat recovery heat storage circuit, a primary steam rankine cycle power generation circuit, and a secondary organic rankine cycle power generation circuit.
The waste heat recovery heat storage loop comprises an evaporator 1, a first preheater 2, a second preheater 4, a high-temperature heat storage water tank 6, a low-temperature heat storage water tank 7 and a low-temperature water pump 13;
the primary steam Rankine cycle power generation loop comprises an evaporator 1, an intermediate heat exchanger 3, a high-temperature heat storage water tank 6, a steam screw expander 8, a first power generator 10 and an intermediate-temperature water pump 12; the evaporator 1, the high-temperature heat storage water tank 6, the steam screw expander 8, the intermediate heat exchanger 3 and the intermediate-temperature water pump 12 are connected in series to form a primary hydraulic medium loop;
the secondary organic Rankine cycle power generation loop comprises an intermediate heat exchanger 3, a second preheater 4, a condenser 5, an organic working medium turbine 9, a second generator 11 and an organic working medium pump 14; wherein the second preheater 4, the intermediate heat exchanger 3, the organic working medium turbine 9, the condenser 5 and the organic working medium pump 14 are connected in series to form a secondary organic working medium loop.
One side of the evaporator 1 and one side of the first preheater 2 are waste heat mediums, and the other side of the evaporator 1 and the other side of the first preheater 2 are hydraulic mediums;
the intermediate heat exchanger 3 and one side of the second preheater 4 are water working media, the other side of the intermediate heat exchanger 3 and the other side of the second preheater 4 are organic working media, the intermediate heat exchanger 3 on one side of the water working media is connected in series in the primary steam Rankine cycle power generation loop, the second preheater 4 on one side of the water working media is connected in series in the waste heat recovery heat storage loop, and the intermediate heat exchanger 3 on one side of the organic working media and the second preheater 4 are connected in series in the secondary organic Rankine cycle power generation loop;
one side of the condenser 5 is a cooling water working medium, the other side of the condenser 5 is an organic working medium, and the condenser 5 on one side of the organic working medium is connected in series in the secondary organic Rankine cycle power generation loop.
The water working medium outlet of the evaporator 1 is communicated with the upper inlet of the high-temperature heat storage water tank 6, the upper outlet of the high-temperature heat storage water tank 6 is communicated with the inlet of the steam screw expander 8 through the high-temperature steam valve 15, the outlet of the steam screw expander 8 is communicated with the water working medium inlet of the intermediate heat exchanger 3 through the intermediate-temperature steam valve 16, and the water working medium outlet of the intermediate heat exchanger 3 is communicated with the water working medium inlet of the evaporator 1 through the first heat exchange water valve 17, the intermediate-temperature water pump 12 and the first intermediate-temperature water valve 18.
The bottom outlet of the high-temperature heat storage water tank 6 is divided into two paths through a first high-temperature water valve 19 and a second high-temperature water valve 23, one path is communicated with the water working medium inlet of the second preheater 4, the other path is communicated with the water working medium inlet of the intermediate heat exchanger 3, the water working medium outlet of the intermediate heat exchanger 3 is communicated with the water working medium inlet of the second preheater 4 through a second heat exchange water valve 24, the water working medium outlet of the second preheater 4 is communicated with the inlet of the low-temperature heat storage water tank 7 through a throttle valve 20, the outlet of the low-temperature heat storage water tank 7 is communicated with the water working medium inlet of the first preheater 2 through a low-temperature water valve 21 and a low-temperature water pump 13, and the water working medium outlet of the first preheater 2 is communicated with the water working medium inlet of the evaporator 1 through a second medium-temperature water valve 22.
The high temperature steam valve 15, the medium temperature steam valve 16, the first heat exchange water valve 17, the first medium temperature water valve 18, the first high temperature water valve 19, the low temperature water valve 21, the second medium temperature water valve 22, the second high temperature water valve 23 and the second heat exchange water valve 24 are all ball valves.
The throttle valve 20 is a sliding sleeve type throttle valve.
The organic working medium outlet of the intermediate heat exchanger 3 is communicated with the inlet of the organic working medium turbine 9, the outlet of the organic working medium turbine 9 is communicated with the organic working medium inlet of the condenser 5, the organic working medium outlet of the condenser 5 is communicated with the organic working medium inlet of the second preheater 4 through the organic working medium pump 14, and the organic working medium outlet of the second preheater 4 is communicated with the organic working medium inlet of the intermediate heat exchanger 3.
The working temperature of the high-temperature heat storage water tank 6 is 200 ℃, and the working temperature of the low-temperature heat storage water tank 7 is 40 ℃.
The working principle of the invention is described in detail as follows:
(1) Normal mode of operation.
The normal operating mode related design conditions are shown in table 1, wherein:
the waste heat medium is middle-low temperature waste heat flue gas, the temperature fluctuation range is 200-320 ℃, and the temperature fluctuation is linear fluctuation. The flow rate of the medium-low temperature waste heat flue gas is 1.0 kg/s, and the exhaust temperature is 120 ℃ after the recovery. The second-level organic Rankine cycle working medium is R245fa;
referring to fig. 2, when there is sufficient medium and low temperature waste heat flue gas available, the system performs both the regenerative and cascade rankine cycle power generation modes. The medium-temperature water pump 12, the low-temperature water pump 13 and the organic working medium pump 14 are operated, and the high-temperature steam valve 15, the medium-temperature steam valve 16, the first heat exchange water valve 17, the first medium-temperature water valve 18, the first high-temperature water valve 19, the throttle valve 20, the low-temperature water valve 21 and the second medium-temperature water valve 22 are opened. The waste heat medium flows into the evaporator 1 and the first preheater 2 in sequence, low-temperature water in the low-temperature heat storage water tank 7 enters the first preheater 2 for preheating through the low-temperature water pump 13 and the low-temperature water valve 21, then is heated to a set temperature through the evaporator 1 and is partially evaporated, the high-temperature water is stored in the high-temperature heat storage water tank 6, and high-temperature saturated steam enters the steam screw expander 8 through the high-temperature steam valve 15 for expansion work and is output by the first generator 10; the medium-temperature steam discharged by the steam screw expander 8 enters the intermediate heat exchanger 3 through the medium-temperature steam valve 16 to be condensed into medium-temperature water, and the medium-temperature water enters the evaporator 1 through the first heat exchange water valve 17, the medium-temperature water pump 12 and the first medium-temperature water valve 18 to absorb heat again to evaporate, so that the first-stage steam Rankine cycle is completed. The high-temperature water stored in the high-temperature heat storage water tank 6 enters the second preheater 4 through the first high-temperature water valve 19 to release heat, and the released low-temperature water enters the low-temperature heat storage water tank 7 through the throttle valve 20 to complete the circulation of the waste heat storage water. The organic working medium absorbs heat in the second preheater 4 for preheating, absorbs heat in the intermediate heat exchanger 3 for evaporation to become saturated steam, the saturated steam enters the organic working medium turbine 9 for expansion work and is output by the second generator 11, the waste gas discharged by the organic working medium turbine 9 enters the condenser 5 for condensation to become saturated liquid, and the saturated liquid enters the preheater 4 and the intermediate heat exchanger 3 again through the organic working medium pump 14 for absorbing heat for evaporation, so that the second-stage organic Rankine cycle is completed.
(2) And a heat storage power generation mode.
Referring to fig. 3, when the waste heat load of the medium and low temperature waste heat flue gas fluctuates drastically, the system performs a single-stage organic rankine cycle power generation mode using the high temperature water stored in the high temperature heat storage water tank 6. The organic working fluid pump 14 is operated and the throttle valve 20, the second high temperature water valve 23 and the second heat exchange water valve 24 are opened. The high-temperature water in the high-temperature heat storage water tank 6 enters the intermediate heat exchanger 3 to release heat through the second high-temperature water valve 23, then enters the second preheater 4 to release heat through the second heat exchange water valve 24 to become low-temperature water, and enters the low-temperature heat storage water tank 7 through the throttle valve 20. The heat released by the high-temperature water in the intermediate heat exchanger 3 and the second preheater 4 drives the secondary organic rankine cycle;
the calculation results are shown in table 2, when the industrial waste heat temperature fluctuates between 200 and 320 ℃, the dryness of the steam generated at the water working medium outlet side of the evaporator 1 changes between 0% and 37.74%, and the higher the inlet temperature of the medium-low temperature waste heat flue gas is, the higher the dryness of the steam is. The working medium of the secondary organic Rankine cycle firstly absorbs heat through the second preheater 4 and is partially evaporated (the dryness is 11 percent); heat is then further extracted from the condensing end of the overhead vapor rankine cycle and fully evaporated (100% dryness). The condensing end waste heat of the top cycle only provides part of the heat source of the bottom organic rankine cycle. When the temperature of the industrial waste heat changes, the cascade Rankine cycle can work stably.
Claims (5)
1. Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation, and is characterized in that: the system comprises a waste heat recovery and heat storage loop, a primary steam Rankine cycle power generation loop and a secondary organic Rankine cycle power generation loop;
the waste heat recovery and heat storage loop comprises an evaporator (1), a first preheater (2), a second preheater (4), a high-temperature heat storage water tank (6), a low-temperature heat storage water tank (7) and a low-temperature water pump (13);
the primary steam Rankine cycle power generation loop comprises an evaporator (1), an intermediate heat exchanger (3), a high-temperature heat storage water tank (6), a steam screw expander (8), a first power generator (10) and a medium-temperature water pump (12); the evaporator (1), the high-temperature heat storage water tank (6), the steam screw expander (8), the intermediate heat exchanger (3) and the intermediate water pump (12) are connected in series to form a primary hydraulic medium loop;
the secondary organic Rankine cycle power generation loop comprises an intermediate heat exchanger (3), a second preheater (4), a condenser (5), an organic working medium turbine (9), a second generator (11) and an organic working medium pump (14); the second preheater (4), the intermediate heat exchanger (3), the organic working medium turbine (9), the condenser (5) and the organic working medium pump (14) are connected in series to form a secondary organic working medium loop;
one side of the evaporator (1) and one side of the first preheater (2) are waste heat mediums, and the other side of the evaporator (1) and the other side of the first preheater (2) are water working mediums;
one side of the intermediate heat exchanger (3) and one side of the second preheater (4) are water working media, the other side of the intermediate heat exchanger (3) and the other side of the second preheater (4) are organic working media, the intermediate heat exchanger (3) on one side of the water working media is connected in series in a primary steam Rankine cycle power generation loop, the second preheater (4) on one side of the water working media is connected in series in a waste heat recovery heat storage loop, and the intermediate heat exchanger (3) on one side of the organic working media and the second preheater (4) are connected in series in a secondary organic Rankine cycle power generation loop;
one side of the condenser (5) is a cooling water working medium, the other side of the condenser (5) is an organic working medium, and the condenser (5) on one side of the organic working medium is connected in series in a secondary organic Rankine cycle power generation loop;
the water working medium outlet of the evaporator (1) is communicated with the upper inlet of the high-temperature heat storage water tank (6), the upper outlet of the high-temperature heat storage water tank (6) is communicated with the inlet of the steam screw expander (8) through the high-temperature steam valve (15), the outlet of the steam screw expander (8) is communicated with the water working medium inlet of the intermediate heat exchanger (3) through the intermediate-temperature steam valve (16), and the water working medium outlet of the intermediate heat exchanger (3) is communicated with the water working medium inlet of the evaporator (1) through the first heat exchange water valve (17), the intermediate-temperature water pump (12) and the first intermediate-temperature water valve (18);
the bottom outlet of the high-temperature heat storage water tank (6) is divided into two paths through a first high-temperature water valve (19) and a second high-temperature water valve (23), one path is communicated with the water working medium inlet of the second preheater (4), the other path is communicated with the water working medium inlet of the intermediate heat exchanger (3), the water working medium outlet of the intermediate heat exchanger (3) is communicated with the water working medium inlet of the second preheater (4) through a second heat exchange water valve (24), the water working medium outlet of the second preheater (4) is communicated with the inlet of the low-temperature heat storage water tank (7) through a throttle valve (20), the outlet of the low-temperature heat storage water tank (7) is communicated with the water working medium inlet of the first preheater (2) through a low-temperature water valve (21) and a low-temperature water pump (13), and the water working medium outlet of the first preheater (2) is communicated with the water working medium inlet of the evaporator (1) through a second intermediate-temperature water valve (22);
the organic working medium outlet of the intermediate heat exchanger (3) is communicated with the inlet of the organic working medium turbine (9), the outlet of the organic working medium turbine (9) is communicated with the organic working medium inlet of the condenser (5), the organic working medium outlet of the condenser (5) is communicated with the organic working medium inlet of the second preheater (4) through the organic working medium pump (14), and the organic working medium outlet of the second preheater (4) is communicated with the organic working medium inlet of the intermediate heat exchanger (3);
when the system works, the temperature of the waste heat medium is 150-400 ℃, and when enough waste heat can be utilized, the system simultaneously performs heat accumulation and cascade Rankine cycle power generation modes; when the waste heat load severely fluctuates, the system utilizes the stored high-temperature water to carry out a single-stage organic Rankine cycle power generation mode.
2. The cascade rankine cycle and two-stage water heat storage-based industrial waste heat recovery power generation system according to claim 1, wherein: the waste heat medium is one of medium and low temperature waste heat flue gas, waste heat steam and waste water.
3. The cascade rankine cycle and two-stage water heat storage-based industrial waste heat recovery power generation system according to claim 1, wherein: the working temperature of the high-temperature heat storage water tank (6) is 150-300 ℃, and the working temperature of the low-temperature heat storage water tank (7) is 30-150 ℃.
4. The cascade rankine cycle and two-stage water heat storage-based industrial waste heat recovery power generation system according to claim 1, wherein: the high-temperature steam valve (15), the medium-temperature steam valve (16), the first heat exchange water valve (17), the first medium-temperature water valve (18), the first high-temperature water valve (19), the low-temperature water valve (21), the second medium-temperature water valve (22), the second high-temperature water valve (23) and the second heat exchange water valve (24) are all ball valves.
5. The cascade rankine cycle and two-stage water heat storage-based industrial waste heat recovery power generation system according to claim 1, wherein: the throttle valve (20) is a sliding sleeve type throttle valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810934630.4A CN108798812B (en) | 2018-08-16 | 2018-08-16 | Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810934630.4A CN108798812B (en) | 2018-08-16 | 2018-08-16 | Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108798812A CN108798812A (en) | 2018-11-13 |
| CN108798812B true CN108798812B (en) | 2023-06-16 |
Family
ID=64080191
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810934630.4A Active CN108798812B (en) | 2018-08-16 | 2018-08-16 | Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108798812B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109668445B (en) * | 2018-12-31 | 2023-11-24 | 浙能资本控股有限公司 | Vertical sintering waste heat driven water vapor and organic Rankine cycle parallel system |
| CN112343677A (en) * | 2019-08-09 | 2021-02-09 | 国家电投集团科学技术研究院有限公司 | Energy storage system based on high-low temperature heat storage and reverse organic Rankine cycle electricity storage |
| CN112577349A (en) * | 2020-11-11 | 2021-03-30 | 中盐华能储能科技有限公司 | Dual-working-medium energy storage system for gradient storage and utilization of waste heat |
| CN115095402B (en) * | 2022-06-22 | 2023-06-16 | 中国科学技术大学 | Carnot battery energy storage system and use method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102006028746A1 (en) * | 2006-06-20 | 2007-12-27 | Gesellschaft für Motoren und Kraftanlagen mbH | Device for converting thermal energy into mechanical energy, comprises evaporator, turbine, recuperator and condenser, where organic working fluid is tetramethylsilane and has specific pressure and temperature |
| CN205714312U (en) * | 2016-04-14 | 2016-11-23 | 许昌中机动力设备有限公司 | A kind of two kinds of working medium Rankine cycle electricity generation systems of waste heat twin-stage |
| CN107288834A (en) * | 2017-07-24 | 2017-10-24 | 中国科学技术大学 | A kind of solar energy overlapping Rankine cycle electricity generation system with different Heat release modes |
| CN208793052U (en) * | 2018-08-16 | 2019-04-26 | 中国科学技术大学 | Industrial afterheat recovery electricity generation system based on overlapping Rankine cycle and two-stage water accumulation of heat |
-
2018
- 2018-08-16 CN CN201810934630.4A patent/CN108798812B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102006028746A1 (en) * | 2006-06-20 | 2007-12-27 | Gesellschaft für Motoren und Kraftanlagen mbH | Device for converting thermal energy into mechanical energy, comprises evaporator, turbine, recuperator and condenser, where organic working fluid is tetramethylsilane and has specific pressure and temperature |
| CN205714312U (en) * | 2016-04-14 | 2016-11-23 | 许昌中机动力设备有限公司 | A kind of two kinds of working medium Rankine cycle electricity generation systems of waste heat twin-stage |
| CN107288834A (en) * | 2017-07-24 | 2017-10-24 | 中国科学技术大学 | A kind of solar energy overlapping Rankine cycle electricity generation system with different Heat release modes |
| CN208793052U (en) * | 2018-08-16 | 2019-04-26 | 中国科学技术大学 | Industrial afterheat recovery electricity generation system based on overlapping Rankine cycle and two-stage water accumulation of heat |
Non-Patent Citations (1)
| Title |
|---|
| 杨富斌 ; 董小瑞 ; 王震 ; 杨凯 ; 张健 ; 张红光 ; .发动机两级有机朗肯循环尾气余热回收系统的研究.车用发动机.2013,(第05期),31-36. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108798812A (en) | 2018-11-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108798812B (en) | Industrial waste heat recovery power generation system based on cascade Rankine cycle and two-stage water heat accumulation | |
| CN107905857B (en) | Staged evaporation combined cycle steam power device | |
| AU2008349706A1 (en) | Method for operating a thermodynamic circuit, as well as a thermodynamic circuit | |
| CN102817657B (en) | Heat pipe technology based organic Rankine cycle low-temperature exhaust heat power generating system | |
| CN203201663U (en) | Britten-steam exhausting type steam Rankine combined cycle power generation device | |
| CN103075216B (en) | Brayton-cascade steam Rankine combined cycle power generation system | |
| CN208793052U (en) | Industrial afterheat recovery electricity generation system based on overlapping Rankine cycle and two-stage water accumulation of heat | |
| CN203626908U (en) | Flue gas waste heat power generating device of low-temperature organic Rankine cycling industrial boiler | |
| CN108771950B (en) | Carbon dioxide circulating power generation system and method adopting chemical absorption pressurization | |
| CN111735237B (en) | Well low temperature heat utilization merit cold joint system | |
| CN103410578A (en) | Low-temperature organic Rankine cycle industrial waste heat power generating equipment | |
| CN110131005B (en) | Double-pressure heat absorption non-azeotropic organic flash evaporation-Rankine cycle medium-low temperature heat energy utilization system | |
| CN112576327A (en) | Efficient ultra-low emission coal-fired power generation system and power circulation method thereof | |
| CN110685764A (en) | Non-azeotropic working medium two-stage organic flash evaporation circulation system and heat energy recovery method thereof | |
| CN103075213B (en) | Cascade type steam Rankine combined cycle generating device | |
| CN114934843A (en) | Multi-energy efficient complementary integrated dual-pressure ORC combined cycle power generation system | |
| CN112096473A (en) | Supercritical CO2 power generation system and method integrating lignite vacuum pre-drying | |
| CN112228175A (en) | Heating system for realizing activation of purified molecular sieve by utilizing low-grade steam of thermal power generating unit | |
| CN111852585A (en) | Combined cycle power plant | |
| CN103277154A (en) | Coal-fired power plant CO2 removal integrated system based on single-cylinder back-pressure steam turbine | |
| CN110185512A (en) | A kind of supply system that industrial afterheat power generation is coupled with heat pump heating | |
| CN114396732B (en) | Component separation type ORC coupling VCR system based on mixed working medium | |
| CN216081028U (en) | Compound circulating device for utilizing flue gas waste heat | |
| CN213392298U (en) | Supercritical CO2 power generation system integrating lignite vacuum pre-drying | |
| CN114811990B (en) | Co-production system and method combining carbon dioxide power cycle and heat pump cycle |
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 |