CN203201663U

CN203201663U - Britten-steam exhausting type steam Rankine combined cycle power generation device

Info

Publication number: CN203201663U
Application number: CN201320042175XU
Authority: CN
Inventors: 王海波
Original assignee: Nanjing Reclaimer Environmental Technology Co Ltd
Current assignee: Nanjing Reclaimer Environmental Technology Co Ltd
Priority date: 2013-01-27
Filing date: 2013-01-27
Publication date: 2013-09-18
Anticipated expiration: 2023-01-27

Abstract

The utility model relates to a Britten-steam exhausting type steam Rankine combined cycle power generation device, which takes exhausted steam of a steam turbine in a high-pressure-end steam Rankine cycle as a heat source of a low-pressure-end steam Rankine cycle steam generator, wherein the high-pressure-end steam Rankine cycle and low-pressure-end steam Rankine cycle are directly combined; gasification latent heat released by steam exhausting and condensation of a high-pressure-end steam Rankine cycle steam turbine is used for low-pressure-end steam Rankine cycle power generation, so that the load of a traditional steam Rankine cycle system condenser can be effectively reduced by more than 10%; with the adoption of a system optimization technology, the cycle absolute thermal efficiency of the whole system can be improved by more than 4%. The Britten-steam exhausting type steam Rankine combined cycle power generation device disclosed by the utility model can be used for energy-saving modification of an existing condensing type or pure condensation type set and can also used for designing and constructing a newly-built set; the economic, social and environment-friendly effects are very obvious.

Description

Boulez pauses-steam-extracting type steam Rankine combined cycle generating unit

Technical field

The present invention relates to a kind of Boulez pauses-steam-extracting type steam Rankine combined cycle generating unit, specifically belong to the thermal power plant field of power equipment technology.

Background technique

Combustion gas one Steam Combined Cycle is because of its thermal efficiency height, series of advantages such as toggle speed is fast, environmental protection condition good, installation period is short, investment cost is low, add the develop rapidly of gas turbine technology in recent years, the gas turbine single-machine capacity also continues to increase, and combined cycle research has caused attention and the enforcement of countries in the world.

External combined cycle generation Study on Technology starts from eighties of last century end of the sixties, development through decades, at present, the combustion gas one steam combined cycle power generating technology of many developed countries such as the U.S., Britain, Japan is comparative maturity, and its power supply efficiency reaches more than 50%.Be about 53% as U.S. CE company; ABB AB is 48%～51.9%; Mitsubishi Heavy Industries Ltd are 5l%～52%.Many companies (as U.S. Texco company, Belgian CMI company etc.) all have combined cycle exhaust heat boiler performance design, system optimization, structure optimization, the manufacturing technology of comparative maturity, and on top of thermodynamic property and the roadability of combined cycle exhaust heat boiler.The Cheng Shi circulation of gas-steam combined circulation and two-fluid circulation-gas turbine steam injection at present just under development and circulate in the backheat of the blower outlet water-spraying evaporation of gas turbine, the representative of this technical development just, the former is full-fledged, obtained huge economic benefit, both are stepping up the back among the research, and the existing application example of Cheng Shi circulation and formal product.

Being the thermal power plant of working medium with the water vapor, is to carry out on a large scale heat energy is transformed into mechanical energy, and the factory that transforms mechanical energy into electricity again.The circulation that the power station is used is very complicated, yet in essence, mainly the Rankine cycle of being made up of equipment such as boiler, steam turbine, vapour condenser, water pumps is finished, its working principle is: feedwater is sent into boiler earlier after the feed water pump pressurization, water is heated the superheated vapor of vaporization, formation High Temperature High Pressure in boiler, the superheated vapor acting of in steam turbine, expanding, become the exhaust steam of low-temp low-pressure, enter vapour condenser at last and be condensed into condensed water, through water pump condensed water is sent into boiler again and carry out new circulation.The complex loops of using as for the thermal power plant only on the Rankine cycle basis, in order to improve the thermal efficiency, is improved and the new circulation that forms is backheat circulation, thermal cycle etc. again, and Rankine cycle has become the basic circulation of modern steam power plant.

Modern big-and-middle-sized steam power plant all adopts the draw gas circulation of heated feed water backheat, steam thermal cycle technology more without any exception, thereby improved the heating mean temperature, except having improved thermal efficiency of cycle significantly, though specific steam consumption increases to some extent, but owing to draw gas step by step the steam discharge rate is reduced, this is conducive to the internal efficiency ratio η of i.e. this circulation of ratio of actual acting amount and theoretical acting amount _OiRaising, solved the difficulty of large steam turbine exhaust stage blade negotiability restriction simultaneously, the vapour condenser volume also can correspondingly reduce.But still discharge a large amount of latent heats of vaporization when steam condenses in vapour condenser, need a large amount of water or air to cool off, namely wasted heat, caused thermo-pollution, wasted electric energy, water resources again.Therefore how effectively to utilize a large amount of latent heat of vaporization that discharges when steam condenses in the vapour condenser, be worth further investigation.

Give off a large amount of flue gases in the station boiler production process, wherein the heat of recyclable utilization is a lot.Though this part residual heat resources waste is huge, recycling has bigger difficulty, and its main cause is: the quality of (1) waste heat is lower, does not find the method for effectively utilizing; (2) reclaim this part waste heat, often the original thermodynamic system of boiler is made bigger change, have certain risk; (3) thermal balance question is difficult to tissue, is difficult to all directly utilize in inside plants, often needs outwards to seek suitable hot user, and hot user often have fluctuation with heat load, thereby limited the versatility of recovery method.

Therefore how to utilize the thermomechanics basic law in steam Rankine cycle thermal power plant, reservation is based on the advantage of the power plant technology of Rankine cycle principle, inquire into new combined cycle theory, really find the new way that increases substantially the steam Rankine-cycle power system thermal efficiency, become the difficult point of this area research.

Summary of the invention

Purpose of the present invention is for solving the problem that above-mentioned steam Rankine cycle exists, a kind of new thermal power plant's combined cycle flow process is proposed, be that Boulez pauses-steam-extracting type steam Rankine combined cycle generating unit, can keep traditional steam Rankine cycle again in the thermal cycle technological merit, reclaim the latent heat of vaporization of drawing gas significantly, the load of traditional Rankine cycle vapour condenser is alleviated significantly, size according to rate of air sucked in required, the absolute amplitude value that alleviates can reach 10%, thereby realize effectively improving the thermal efficiency of whole Combined Cycle Unit, finally reach energy-saving and cost-reducing, improve the purpose of system thermal efficiency.

The objective of the invention is to realize by following measure:

A kind of Boulez pauses-steam-extracting type steam Rankine combined cycle generating unit, and this device comprises Boulez pause circulation, the Rankine cycle of high voltage terminal steam and the Rankine cycle of low voltage terminal steam, it is characterized in that:

Air 28 is sent into fuel-burning equipment 30 through gas compressor 29, fully burns with the fuel 33 that enters, and the high-temperature flue gas of generation enters gas turbine 31, drags gas turbine powered generator 34 generating, finishes the circulation of pausing of gas turbine unit Boulez.

The high-temperature flue gas 32 that described gas turbine 31 is discharged is as the thermal source of steam-extracting type steam Rankine combined cycle system, and high-temperature flue gas 32 is discharged after exhaust heat boiler body 1, low-pressure superheater 15, high-pressure superheater 3, high-pressure feed-water heater 8, low-pressure feed heater 11 coolings along flue 20.

The Rankine cycle of described high voltage terminal steam, refer to the saturated vapour 2 that come out by exhaust heat boiler body 1, form high pressure superheated steam 3-1 through high-pressure superheater 3, send into high-pressure turbine 4 and drive generator 19 generatings, the exhaust steam that high-pressure turbine 4 comes out forms water of condensation 6 in vapour condenser 5, condensed water 6 is sent into high-pressure feed-water heater 8, exhaust heat boiler body 1 through condensate pump 13, oxygen-eliminating device 12, high pressure water pump 7, exhaust heat boiler body 1 produces saturated vapour again, thereby forms high voltage terminal steam Rankine cycle loop.

The Rankine cycle of described low voltage terminal steam, refer to that steam generator 26 adopts the 4-1 that draws gas of steam turbine 4 in the Rankine cycle of high voltage terminal steam as thermal source, with low voltage terminal feed water direct Hybrid Heating or indirect heat exchange, produce low-pressure saturated steam 5-1, the 4-1 that draws gas returns high voltage terminal steam Rankine cycle system through the condensed water that steam generator 26 forms through return piping 27, form low-pressure superheated steam 16 through low-pressure superheater 15, send into low-pressure turbine 17 and drive generator 19 generatings; The exhaust steam that low-pressure turbine 17 comes out condenses into water of condensation 9 at low pressure vapour condenser 18, water of condensation 9 is through condensate pump 10, low-pressure feed heater 11, secondary low-pressure feed heater 14, send into steam generator 26, steam generator 26 produces saturated vapour 5-1 again, thereby forms low voltage terminal steam Rankine cycle loop.

Described steam generator 26 adopts the operation under positive pressure mode.

The Rankine cycle of described high voltage terminal steam and the Rankine cycle of low voltage terminal steam directly combine by steam generator 26, the latent heat of vaporization that discharges when drawing gas the 4-1 condensation in the Rankine cycle of high efficiente callback temperature end steam is used for low-temperature end steam Rankine cycle generating, the low-pressure superheater technology that adopts, receive the advantage of thermal cycle technology again, therefore can significantly improve the thermal efficiency of whole circulation.

Feedwater in the described evaporation generator 26 and the 4-1 that draws gas adopt direct Hybrid Heating or hot mode gradually indirectly.

When the feedwater in the described evaporation generator 26 is adopted direct Hybrid Heating mode with the 4-1 that draws gas, be provided with recovery line 27: the 4-1 that draws gas directly returns high voltage terminal steam Rankine cycle system from steam generator 26 through return piping 27 through the condensed water that steam generator 26 forms; Perhaps return high voltage terminal steam Rankine cycle loop from condensate pump 10 outlet lines through recovery line 27.

When the feedwater in the described evaporation generator 26 is adopted the indirect heating mode with the 4-1 that draws gas, be provided with recovery line 27: the 4-1 that draws gas directly returns high voltage terminal steam Rankine cycle system from steam generator 26 through return piping 27 through the condensed water that steam generator 26 forms; Water of condensation 9 is returned high voltage terminal steam Rankine cycle loop through condensate pump 10, recovery line 27, gets back to the inlet line of condensate pump 10 again through return piping 27-1 from oxygen-eliminating device 12 outlet lines.

When described low-pressure feed heater 11 adopted the separated type heat exchange mode with flue gas, low-pressure feed heater was compound phase change heat exchanger, comprises vaporizer 11-1, condenser 11-2, and vaporizer 11-1 and condenser adopt the structure of split type or integral type; Phase-change working substance wherein adopts water or other suitable materials; Phase-change working substance absorbs flue gas in vaporizer 11-1 heat produces saturated vapour, saturated vapour is by condenser 11-2 and low voltage terminal water of condensation 9 wall-type heat exchanges, the cooling back forms condensation water and is absorbed the heat generation steam of flue gas again by vaporizer 11-1, thereby forms the inner cyclic process of phase-change working substance; Phase-change working substance adopts natural circulation or pump circulation mode; Preferable methods is the split type layout of vaporizer, condenser, and namely vaporizer 11-1 is arranged in the flue 20, condenser 11-2 is arranged in outside the flue, and phase-change working substance adopts water, adopts natural circulation mode.

Described high-pressure feed-water heater 8, steam vaporizer 26, low-pressure feed heater 14, low-pressure feed heater 11, high-pressure superheater 3, low-pressure superheater 15 can arrange one or more respectively, adopt series, parallel or series-parallel connection mode to connect.

Described vapour condenser 18, vapour condenser 5 arrange according to routine techniques, adopt water or air etc. as cooling medium.

The heat-exchanging element of mentioned aforementioned device can adopt tubulation, fin tube, coiler or spiral groove pipe among the present invention, or adopts the pipe of other augmentation of heat transfer measures or the hollow cavity heat-exchanging element of other patterns.

The a little higher than flue gas acid dew point temperature of wall surface temperature of the vaporizer 11-1 heat exchanger surface of control low-pressure feed heater 11, or the cold end corrosion of adopting corrosion-resistant material effectively to alleviate flue gas, can effectively reduce temperature of exhaust fume, avoid flue gas low-temperature corrosion time, the high efficiente callback fume afterheat.

Unaccounted equipment and standby system thereof, pipeline, instrument, valve among the present invention, be incubated, have the known mature technologies of employing such as regulatory function bypass facility and carry out supporting.

Be provided with safety, regulating controller with system support of the present invention, adopt the known ripe control technique of existing steam Rankine cycle power station, Cheng Shi cycle power plant or gas-steam combined cycle power plant to carry out supporting, make steam-extracting type steam Rankine combined cycle generating unit energy economy, safety, high thermal efficiency operation, reach energy saving purposes.

The present invention has following advantage compared to existing technology:

1, the Boulez of the present invention's design pauses-steam-extracting type steam Rankine combined cycle generating unit, be different from traditional Boulez and pause-the steam Rankine cycle system, with drawing gas as the thermal source of the steam generator of low voltage terminal steam Rankine cycle of high-pressure turbine, directly with the feedwater mixing of low voltage terminal steam Rankine cycle or the feedwater of indirect heating low voltage terminal steam Rankine cycle, produce low pressure steam, thereby the Rankine cycle of high voltage terminal steam and the Rankine cycle of low voltage terminal steam are combined by steam generator is ingenious, the latent heat of vaporization of drawing gas of high voltage terminal steam Rankine cycle all is utilized effectively, the absolute amplitude value that the load of vapour condenser alleviates can reach 30%, and the absolute efficiency value of whole system circulation can improve more than 2%; Adopt the system optimization technology, the absolute amplitude value that the efficient of combined cycle system improves can reach more than 4%.

2, the fume afterheat of power plant is realized the high efficiente callback utilization: when the heat exchanger that back-end ductwork arranges adopts phase-change heat-exchanger, waste heat that can the high efficiente callback flue gas, temperature of exhaust fume can be reduced to about 120 ℃, when the phase-change heat-exchanger vaporizer adopts resistant material, temperature of exhaust fume can reduce more, reach about 85 ℃, operation to system for desulfuration and denitration is very favourable, when effectively avoiding the flue gas low-temperature corrosion, the heat that reclaims is used for Rankine cycle system and efficiently generates electricity, and more meets the cascaded utilization of energy principle.

3, safety in operation obviously improves:

The high-pressure steam turbine displacement of high voltage terminal steam Rankine cycle reduces significantly, the operating conditions of steam turbine last stage blade be improved significantly; Low-pressure superheater in the Rankine cycle of low voltage terminal steam, because of pressure lower, safety in operation improves, superheated vapor is adopted in the admission of low-pressure turbine, traditional advantage of thermal cycle again is not fully exerted, can effectively solve last stage vane of steam turbine brings because of wet vapor in traditional steam Rankine cycle problem design, manufacturing and operation problem, obviously improve before the vibration of steam turbine generator set.

4, the solution of the present invention both can be used for design, the construction of newly-built power plant system, also can be used for the reducing energy consumption to existing Rankine cycle sucking condensing type or pure condensate formula unit or back pressure unit, energy is the potentiality of excavating device fully, vitalize existing assets, traditional condensed steam type of closing down or sucking condensing type unit are radiated vigour again, meet the industrial policy of country simultaneously, economical, the Security of unit operation are reliably guaranteed, can effectively improve the thermal efficiency of system.

Description of drawings

Fig. 1 is that a kind of Boulez of the present invention pauses-steam-extracting type steam Rankine combined cycle generating unit schematic flow sheet.

Among Fig. 1: 1-exhaust heat boiler body, 2-saturated vapour, 3-high-pressure superheater, the 3-1-high pressure superheated steam, the 4-high-pressure turbine, the 4-1-high-pressure turbine draws gas, the 5-vapour condenser, 5-1-low-pressure saturated steam, 6-condensed water, the 7-high pressure water pump, 8-high-pressure feed-water heater, 9-low pressure condensate water, the 10-condensate pump, 11-low-pressure feed heater, 11-1-vaporizer, the 11-2-condenser, 12-oxygen-eliminating device, 13-condensate pump, 14-secondary low-pressure feed heater, 15-low-pressure superheater, 16-low-pressure superheated steam, the 17-low-pressure turbine, 18-vapour condenser, 19-generator, the 20-flue, 26-steam generator, 27-return piping, the 27-1-return piping, 28-air, 29-gas compressor, the 30-fuel-burning equipment, 31-gas turbine, 32-high-temperature flue gas, 33-fuel, the 34-gas turbine powered generator.

Embodiment

Below in conjunction with the drawings and specific embodiments the present invention is described in further detail.

Embodiment 1:

As shown in Figure 1, a kind of steam-extracting type steam Rankine combined cycle generating unit, this device comprises the Rankine cycle of high voltage terminal steam, the Rankine cycle of low voltage terminal steam:

The Rankine cycle of described low voltage terminal steam, refer to that steam generator 26 adopts the 4-1 that draws gas of steam turbine 4 in the Rankine cycle of high voltage terminal steam as thermal source, with the low voltage terminal direct Hybrid Heating that feeds water, produce low-pressure saturated steam 5-1, the 4-1 that draws gas returns high voltage terminal steam Rankine cycle system through the condensed water that steam generator 26 forms through return piping 27, form low-pressure superheated steam 16 through low-pressure superheater 15, send into low-pressure turbine 17 and drive generator 19 generatings; The exhaust steam that low-pressure turbine 17 comes out condenses into water of condensation 9 at low pressure vapour condenser 18, water of condensation 9 is through condensate pump 10, low-pressure feed heater 11, secondary low-pressure feed heater 14, send into steam generator 26, steam generator 26 produces saturated vapour 5-1 again, thereby forms low voltage terminal steam Rankine cycle loop.

Described vapour condenser 18, vapour condenser 5 arrange according to routine techniques, adopt water as cooling medium.

Be provided with safety, regulating controller with system support of the present invention, adopt the known ripe control technique of existing steam Rankine cycle power station, Cheng Shi cycle power plant or gas-steam combined cycle power plant to carry out supporting, make Boulez pause-steam-extracting type steam Rankine combined cycle generating unit can economy, safety, high thermal efficiency operation, reaches energy saving purposes.

Though the present invention with preferred embodiment openly as above, they are not to limit the present invention, anyly are familiar with this skill person, without departing from the spirit and scope of the invention, when doing various variations or retouching, belong to the present invention's protection domain equally certainly.Therefore protection scope of the present invention should with the application claim was defined is as the criterion.

Claims

1. a Boulez pauses-steam-extracting type steam Rankine combined cycle generating unit, and this device comprises Boulez pause circulation, the Rankine cycle of high voltage terminal steam and low voltage terminal organic rankine cycle system, it is characterized in that:

Air (28) is sent into fuel-burning equipment (30) through gas compressor (29), and with fully burning of the fuel that enters (33), the high-temperature flue gas of generation enters gas turbine (31), drags gas turbine powered generator (34) generating, finishes the circulation of pausing of gas turbine unit Boulez; The high-temperature flue gas (32) that described gas turbine (31) is discharged is as the thermal source of steam-extracting type steam Rankine combined cycle system;

The Rankine cycle of described high voltage terminal steam, refer to the saturated vapour (2) that come out by exhaust heat boiler body (1), form high pressure superheated steam (3-1) through high-pressure superheater (3), send into high-pressure turbine (4) and drive generator (19) generating, the exhaust steam that high-pressure turbine (4) comes out forms water of condensation (6) in vapour condenser (5), send into exhaust heat boiler body (1) through condensed water (6) through high pressure water pump (7), exhaust heat boiler body (1) produces saturated vapour again, thereby forms high voltage terminal steam Rankine cycle loop;

The Rankine cycle of described low voltage terminal steam, refer to that draw gas (4-1) of steam turbine (4) in the Rankine cycle of steam generator (26) employing high voltage terminal steam is as thermal source, the feedwater of heating low voltage terminal steam Rankine cycle, the low-pressure saturated steam (5-1) that steam generator (26) produces, form low-pressure superheated steam (16) through low-pressure superheater (15), send into low-pressure turbine (17) and drive generator (19) generating; The exhaust steam that low-pressure turbine (17) comes out condenses into water of condensation (9) at vapour condenser (18), water of condensation (9) is sent into steam generator (26) through condensate pump (10), steam generator (26) produces saturated vapour (5-1) again, thereby forms low voltage terminal steam Rankine cycle loop;

Described steam generator (26) adopts the operation under positive pressure mode;

The Rankine cycle of described high voltage terminal steam and the Rankine cycle of low voltage terminal steam directly combine by steam generator (26), and the latent heat of vaporization that discharges when reclaiming the steam condensation of temperature end steam Rankine cycle is used for low-temperature end steam Rankine cycle generating.

2. device according to claim 1 is characterized in that:

Be provided with high-pressure feed-water heater (8):

The saturated vapour (2) that exhaust heat boiler body (1) comes out forms high pressure superheated steam (3-1) through high-pressure superheater (3), sends into high-pressure turbine (4) and drives generator (19) generating; The exhaust steam (4-1) that high-pressure turbine (4) comes out forms condensed water (6) through vapour condenser (5), condensed water (6) is sent into high-pressure feed-water heater (8), exhaust heat boiler body (1) through high pressure water pump (7), exhaust heat boiler body (1) produces saturated vapour again, thereby forms high voltage terminal steam Rankine cycle loop.

3. device according to claim 1 is characterized in that:

Be provided with oxygen-eliminating device (12):

The saturated vapour (2) that exhaust heat boiler body (1) comes out forms high pressure superheated steam (3-1) through high-pressure superheater (3), sends into high-pressure turbine (4) and drives generator (19) generating; The exhaust steam (4-1) that high-pressure turbine (4) comes out forms condensed water (6) through vapour condenser (5), condensed water (6) is after condensate pump (13), oxygen-eliminating device (12) deoxygenation, send into exhaust heat boiler body (1) through high pressure water pump (7), exhaust heat boiler body (1) produces saturated vapour again, thereby forms high voltage terminal steam Rankine cycle loop.

4. device according to claim 1 is characterized in that:

Feedwater in the described steam generator (26) and draw gas (4-1) adopt direct Hybrid Heating or hot mode gradually indirectly.

5. device according to claim 4 is characterized in that:

When the feedwater in the described steam generator (26) and draw gas (4-1) adopted direct Hybrid Heating mode, be provided with recovery line (27): draw gas (4-1) directly returned high voltage terminal steam Rankine cycle system from steam generator (26) through return piping (27) through the condensed water that steam generator (26) forms; Perhaps return high voltage terminal steam Rankine cycle loop from condensate pump (10) outlet line through recovery line (27).

6. device according to claim 4 is characterized in that:

When the feedwater in the described steam generator (26) is adopted the indirect heating mode with draw gas (4-1), be provided with recovery line (27): draw gas (4-1) directly returns high voltage terminal steam Rankine cycle system from steam generator (26) through return piping (27) through the condensed water that steam generator (26) forms; Water of condensation (9) is returned high voltage terminal steam Rankine cycle loop through condensate pump (10), recovery line (27), again the inlet line of getting back to condensate pump (10) through return piping (27-1) from oxygen-eliminating device (12) outlet line.

7. according to the described device of one of claim 1 to 6, it is characterized in that:

Be provided with low-pressure feed heater (11):

Saturated vapour (5-1) by steam vaporizer (26) produces forms low-pressure superheated steam (16) through low-pressure superheater (15), sends into low-pressure turbine (17) and drives generator (19) generating; The exhaust steam that low-pressure turbine (17) comes out condenses into water of condensation (9) at vapour condenser (18), water of condensation (9) is sent into steam vaporizer (26) through condensate pump (10), low-pressure feed heater (11), after (4-1) heating of drawing gas of high-pressure turbine (4), produce saturated vapour (5-1), thereby form low voltage terminal steam Rankine cycle loop.

8. device according to claim 7 is characterized in that:

Be provided with secondary low-pressure feed heater (14):

Saturated vapour (5-1) by steam vaporizer (26) produces forms low-pressure superheated steam (16) through low-pressure superheater (15), sends into low-pressure turbine (17) and drives generator (19) generating; The exhaust steam that low-pressure turbine (17) comes out condenses into water of condensation (9) at vapour condenser (18), water of condensation (9) is sent into steam vaporizer (26) through condensate pump (10), low-pressure feed heater (11), secondary low-pressure feed heater (14), after (4-1) heating of drawing gas of high-pressure turbine (4), produce saturated vapour (5-1), thereby form low voltage terminal steam Rankine cycle loop.

9. device according to claim 7 is characterized in that:

Described low-pressure feed heater (11) adopts dividing wall type or separated type heat exchange mode with flue gas.

10. device according to claim 9 is characterized in that:

When described low-pressure feed heater (11) adopts the separated type heat exchange mode with flue gas, comprise vaporizer (11-1), condenser (11-2); Vaporizer (11-1) is arranged in fume side, follow the flue gas wall-type heat exchange by phase-change working substance, the phase-change working substance heat absorption produces steam, steam is by the feedwater wall-type heat exchange of condenser (11-2) with the Rankine cycle of low voltage terminal steam, the cooling back forms condensation water and is absorbed the heat generation steam of flue gas again by vaporizer (11-1), thereby forms the inner cyclic process of phase-change working substance.

11. device according to claim 10 is characterized in that:

Described high-pressure superheater (3), low-pressure superheater (15), high-pressure feed-water heater (8), secondary low-pressure feed heater (14), low-pressure feed heater (11), steam vaporizer (26) can arrange one or more, adopt series, parallel or series-parallel connection mode to connect.