CN102012039A - Forced circulation air preheat system - Google Patents
Forced circulation air preheat system Download PDFInfo
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- CN102012039A CN102012039A CN2010106016293A CN201010601629A CN102012039A CN 102012039 A CN102012039 A CN 102012039A CN 2010106016293 A CN2010106016293 A CN 2010106016293A CN 201010601629 A CN201010601629 A CN 201010601629A CN 102012039 A CN102012039 A CN 102012039A
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- air
- forced circulation
- hypomere
- heat exchanger
- exchanger tube
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
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Abstract
The invention discloses a forced circulation air preheat system which is characterized in that a lower-section air preheater is internally provided with at least two gas ducts and at least two air flues, wherein the numbers of the gas ducts and the air flues are same; each gas duct is isolated from each air flue; the gas ducts and the air flues are arranged at intervals; a lower-section heat exchange tube is arranged between each two adjacent gas duct and air flue, and all the lower-section heat exchange tubes are communicated; and a transporter is arranged between the water inlet and water outlet of each lower-section heat exchange tube, and is connected with a circuit controller. Because the forced circulation air preheat system is subject to secondary heat exchange by means of a medium, the medium generates phase change in the lower-section heat exchange tubes so as to maintain the wall surface temperature of the lower-section heat exchange tubes to be equal to the phase change temperature of water, and the pressure in the lower-section heat exchange tubes is adjusted in the gas ducts so as to control the tube wall temperature of the lower-section heat exchange tubes to be higher than the acid dew point temperature of flue, thus avoiding the parts, which are positioned in the gas ducts, of the lower-section heat exchange tubes from acid corrosion, thereby solving the problem of low temperature corrosion caused by the smoke removal temperature reduction of the air preheater.
Description
Technical field
The present invention relates to boiler plant heat recovery technology field, particularly a kind of air preheating system of realizing reducing the boiler exhaust gas heat loss and making full use of waste heat by forced circulation.
Background technology
Existing boiler plant, as all kinds of high pressure, super-pressure, subcritical pressure boiler, the exhaust gas temperature of its air preheater rear pass is higher, usually air preheater is carried out air and the exchange of flue gas direct heat as flue surface in order to improve boiler thermal output.
Use wider product at present and mainly contain tubular air preheater and regenerative air preheater.From former boiler design technology, conventional tubular or regenerative air preheater are for avoiding taking place cold end corrosion and stifled ash, and for example, when acid dew point was 80 ℃, then exhaust gas temperature will be higher than 135 ℃ (as if 20 ℃ of import wind-warm syndrome).Further reduce the exhaust gas temperature of boiler and guarantee that the tube wall temperature of air preheater is not less than flue gas dew point as need, adopting conventional art is to accomplish.Therefore usually when guaranteeing safe operation of the boiler, exhaust gas temperature need design higherly, thereby causes the boiler exhaust gas heat loss.
The import wind-warm syndrome of existing air preheater is along with can change season simultaneously, and exhaust gas temperature also is subjected to influences such as load, burning, when the wall surface temperature of air preheater is lower than acid dew-point temperature, cold end corrosion will take place and cause local dust stratification, SR increase, heating surface fouling etc. in the air preheater end, thereby influences the thermal efficiency of boiler.
Summary of the invention
The technical problem that the present invention mainly solves provides a kind of forced circulation air preheating system, the cold end corrosion that this forced circulation air preheating system produces in the time of can avoiding reducing the exhaust gas temperature of air preheater, reduce the exhaust gas temperature of air preheat simultaneously, improve the utilization ratio of fume afterheat.
In order to address the above problem, the invention provides a kind of forced circulation air preheating system, this forced circulation air preheating system comprises the hypomere air preheater, in this hypomere air preheater, be provided with quantity identical at least two flues and at least two air channels, each flue and air channel are isolated mutually, flue gas and air do not carry out direct heat transfer by tube wall, and flue and air channel are adjacent at interval, between this adjacent flue and air channel, be respectively equipped with the hypomere heat exchanger tube of connection, be provided with conveying device between the water inlet end of this hypomere heat exchanger tube and the water side, this conveying device is connected with circuit controller.
Preferably, described hypomere heat exchanger tube is in parallel distributes.
Preferably, between the water side of described hypomere heat exchanger tube and conveying device, be provided with the expansion tank of adjustable water saving pressure and and be connected and accept first switch of circuit controller control with conveying device.
Preferably, described first switch comprises electrically operated valve or electromagnetic valve.
Preferably, described conveying device comprises water circulating pump.
Preferably, described forced circulation air preheating system also comprises the stage casing air preheater that is connected with the hypomere air preheater, and wherein two air channels are arranged in a crossed manner on this stage casing air preheater.
Preferably, described forced circulation air preheating system also comprises the epimere air preheater that is connected with the stage casing air preheater, this epimere air preheater be provided with its in the conduit that is connected with water cooler of epimere heat exchanger tube, this conduit is provided with the second switch that is connected and controls the conduit condensing water flow with described circuit controller.
Preferably, described gate-controlled switch comprises electrically operated valve or electromagnetic valve.
Preferably, the condensing water conduit hydraulic pressure of the inlet of described epimere heat exchanger tube, outlet hydraulic pressure and introducing, the heat regenerative system of drawing is identical.
Preferably, at least two of described hypomere air preheater outlet air channels are higher than described at least two gas approach.
Forced circulation air preheating system of the present invention, in this hypomere air preheater, be provided with quantity identical at least two flues and at least two air channels, each flue and air channel are isolated mutually, flue gas and air do not carry out direct heat transfer by tube wall, and flue and air channel are adjacent at interval, be respectively equipped with the hypomere heat exchanger tube of connection between this adjacent flue and air channel, be provided with conveying device between the water inlet end of this hypomere heat exchanger tube and the water side, this conveying device is connected with circuit controller.Water by the hypomere heat exchanger tube that is positioned at flue during work absorbs heat, make water become steam, this steam is passed to heat in the hypomere heat exchanger tube in the air channel, this steam make with the hypomere heat exchanger tube in the air themperature that contacts raise, simultaneously with the air contact process in make steam condense into water to flow in the header, this water carries out forced circulation under described conveying device is carried, realize Continuous Heat Transfer.
Because the forced circulation air preheating system is to carry out secondary heat exchange by medium, medium undergoes phase transition in the hypomere heat exchanger tube, make the wall surface temperature of hypomere heat exchanger tube maintain the phase transition temperature of water, in flue, hypomere heat exchanger tube wall temperature (water alternating temperature degree) is controlled on the flue gas acid dew point temperature all the time by the pressure of regulating in the hypomere heat exchanger tube (being expansion tank pressure), avoid the hypomere heat exchanger tube to be positioned at the pipeline generation acid corrosion of flue, thereby solve the problem of traditional air preheater cold end corrosion.
When the coal combustion speciogenesis of boiler changed, acid dew-point temperature also can change, and by the phase transition temperature of medium in the expansion tank pressure change hypomere heat exchanger tube, the wall surface temperature of hypomere heat exchanger tube was controlled on the acid dew-point temperature all the time, prevented that acid from revealing corrosion.Control gate-controlled switch greater than regulating the water cooler condensate flow by circuit controller simultaneously, make the cigarette temperature behind the water cooler change, changing the flue-gas temperature behind the hypomere air preheater, thereby realize the purpose that prevents boiler flue corrosion and reduce exhaust gas temperature to greatest extent.
Description of drawings
Fig. 1 is a forced circulation air preheating system example structure schematic diagram of the present invention;
Fig. 2 is along A-A direction sectional structure schematic diagram;
Fig. 3 is another example structure schematic diagram of forced circulation air preheating system of the present invention.
Below in conjunction with embodiment, and with reference to accompanying drawing, realization, functional characteristics and the advantage of the object of the invention is described further.
The specific embodiment
As Fig. 1, Fig. 2 and shown in Figure 3, the invention provides a kind of forced circulation air preheating system embodiment.
This forced circulation air preheating system comprises: the hypomere air preheater, be respectively equipped with identical at least two flues (exhaust gases passes) of quantity and at least two air channels (air duct) in this hypomere air preheater, promptly the quantity of flue is identical with the quantity in air channel.Each flue and air channel are isolated mutually, flue gas and air do not carry out direct heat transfer by tube wall, and flue and air channel are adjacent at interval, between this adjacent flue and air channel, be respectively equipped with the hypomere heat exchanger tube of connection, be provided with conveying device between the water inlet end of this hypomere heat exchanger tube and the water side, as adopting the water circulating pump of variable frequency adjustment, this conveying device is connected with circuit controller; Described hypomere heat exchanger tube can be in parallel the distribution.
Be provided with the expansion tank of adjustable water saving pressure and and be connected with conveying device and accept first switch of circuit controller control between the water side of described hypomere heat exchanger tube and conveying device, this first switch comprises electrically operated valve or electromagnetic valve.
During work, flue gas is from top to bottom by described hypomere air preheater.Absorb the heat of flue gas by the water of the hypomere heat exchanger tube that is positioned at flue, make water become steam, this steam is passed to heat the hypomere heat exchanger tube that is positioned at the air channel, this steam raises the air themperature that contacts with hypomere heat exchanger tube outer wall, simultaneously with the air contact process in make steam in the hypomere heat exchanger tube condense into water to flow in the header, this water carries out forced circulation under described conveying device is carried, realize Continuous Heat Transfer.
Because the forced circulation air preheating system is to carry out secondary heat exchange by medium, medium undergoes phase transition in the hypomere heat exchanger tube, make the wall surface temperature of hypomere heat exchanger tube maintain the phase transition temperature of water, in flue, make hypomere heat exchanger tube wall temperature (water alternating temperature degree) be controlled on the acid dew-point temperature all the time by the pressure of regulating in the hypomere heat exchanger tube (being expansion tank pressure), avoid the hypomere heat exchanger tube to be positioned at the pipeline generation acid corrosion of flue, thereby solve the problem of traditional air preheater cold end corrosion.
When the coal combustion speciogenesis of boiler changes, acid dew-point temperature also can change, can be by the phase transition temperature of medium in the expansion tank pressure change hypomere heat exchanger tube, the wall surface temperature of hypomere heat exchanger tube is controlled on the acid dew-point temperature all the time, prevent that acid from revealing corrosion.
In last embodiment, water source in the described epimere heat exchanger tube comes from the condensate water of steam turbine water supply heat back system, hydraulic pressure is the pipeline pressure that attracts condensate water, and the condensing water conduit hydraulic pressure of the inlet of promptly described epimere heat exchanger tube, outlet hydraulic pressure and introducing, the heat regenerative system of drawing is identical; At least two outlet air channels of described hypomere air preheater are higher than described at least two gas approach.
As shown in Figure 3, described forced circulation air preheating system also comprises the stage casing air preheater that is connected with the hypomere air preheater, wherein two air channels are arranged in a crossed manner on this stage casing air preheater, flue gas in the flue is fully contacted, the heat exchange coefficient of flue gas in air in the raising air channel and the flue with the air channel outer wall.
On the air preheater of described stage casing, be provided with the epimere air preheater, this epimere air preheater is provided with the epimere heat exchanger tube, this epimere heat exchanger tube and water cooler connect, this conduit is provided with the second switch that is connected and controls the conduit condensing water flow with described circuit controller, and this second switch comprises electrically operated valve or electromagnetic valve.
Technique effect for better explanation the present invention reaches specifies the course of work.
Described water cooler is the gas one water heat-exchanger rig of flue gas and condensate water, structure and economizer are similar, high-temperature flue gas about 330-350 ℃ can be reduced to about 250-270 ℃, high-temperature flue gas and low-temperature condensate carry out heat exchange, and the water-cooled source comes from the condensate water of water supply heat back system.Can control the flow of inlet water that second switch is regulated water cooler by circuit controller as required, realize the cooldown rate of control water cooler flue gas.
Stage casing heat exchanger tube on the air preheater of stage casing adopts oblique layout, and air flows to making progress along pipe in the heat exchanger tube of the stage casing of this oblique layout, and flue gas flows downward outside the heat exchanger tube of stage casing and washes away heat exchanger tube.This stage casing air preheater can be reduced to 250-270 ℃ high-temperature flue gas about 160 ℃, simultaneously normal temperature air is heated to temperature required level, supplies with boiler-burner and burns.
The hypomere air preheater can adopt four passages, and wherein two passages are flue, and two passages are the air channel, and each flue and air channel are isolated mutually, and flue gas and air do not carry out direct heat transfer by tube wall, and flue is adjacent at interval with the air channel.Hypomere heat exchanger tube on the hypomere air preheater adopts parallel transistor to arrange and puts, according to circumstances the hypomere heat exchanger tube also can adopt horizontal positioned, can vertical or oblique placement, carry out the carbonated drink phase-change heat-exchange for aqueous medium in the hypomere heat exchanger tube.The hypomere heat exchanger tube absorbs flue gas heat in flue, make the water evaporation in the hypomere heat exchanger tube produce steam, and heat is delivered to the hypomere heat exchanger tube that is positioned at the air channel, makes the atmosphere temperature rising in the air channel, and it is lower to make exhaust gas temperature reduce to; The interior steam of hypomere heat exchanger tube is condensed in the water inflow header carry out next circulation.By be connected water lateral pressure in the expansion tank control hypomere heat exchanger tube with described hypomere air preheater, force to promote the reciprocation cycle of carbonated drink by water circulating pump, for circulation provides power and carries out moisturizing.
In this system, it is carried out multi-faceted adjusting, can make the flue-gas temperature behind the air preheater can reduce to alap level, reach the purpose that reduces heat loss due to exhaust gas by circuit controller.Because exhaust gas temperature is reduced, the flue gas actual flow will reduce thereupon, so also corresponding the reducing of flow velocity of the heat exchanger tube in the sweep of gases air preheater, heat exchanger tube will be improved by the abrasion condition of flying dust in the flue gas, prevent the stifled ash of dewfall.
The above only is the preferred embodiments of the present invention; be not so limit claim of the present invention; every equivalent structure or equivalent flow process conversion that utilizes specification of the present invention and accompanying drawing content to be done; or directly or indirectly be used in other relevant technical fields, all in like manner be included in the scope of patent protection of the present invention.
Claims (10)
1. forced circulation air preheating system, it comprises the hypomere air preheater, it is characterized in that:
In this hypomere air preheater, be provided with quantity identical at least two flues and at least two air channels, each flue and air channel are isolated mutually, and flue and air channel are adjacent at interval, between this adjacent flue and air channel, be respectively equipped with the hypomere heat exchanger tube of connection, be provided with conveying device between the water inlet end of this hypomere heat exchanger tube and the water side, this conveying device is connected with circuit controller.
2. forced circulation air preheating system according to claim 1 is characterized in that:
Described hypomere heat exchanger tube is in parallel to distribute.
3. forced circulation air preheating system according to claim 1 and 2 is characterized in that:
Between the water side of described hypomere heat exchanger tube and conveying device, be provided with the expansion tank of adjustable water saving pressure and and be connected and accept first switch of circuit controller control with conveying device.
4. forced circulation air preheating system according to claim 3 is characterized in that:
Described first switch comprises electrically operated valve or electromagnetic valve.
5. forced circulation air preheating system according to claim 1 and 2 is characterized in that:
Described conveying device comprises water circulating pump.
6. forced circulation air preheating system according to claim 1 and 2 is characterized in that:
Described forced circulation air preheating system also comprises the stage casing air preheater that is connected with the hypomere air preheater, and wherein two air channels are arranged in a crossed manner on this stage casing air preheater.
7. forced circulation air preheating system according to claim 1 and 2 is characterized in that:
Described forced circulation air preheating system also comprises the epimere air preheater that is connected with the stage casing air preheater, this epimere air preheater be provided with its in the conduit that is connected with water cooler of epimere heat exchanger tube, this conduit is provided with the second switch that is connected and controls the conduit condensing water flow with described circuit controller.
8. forced circulation air preheating system according to claim 7 is characterized in that:
Described second switch comprises electrically operated valve or electromagnetic valve.
9. forced circulation air preheating system according to claim 7 is characterized in that:
The condensing water conduit hydraulic pressure of the inlet of described epimere heat exchanger tube, outlet hydraulic pressure and introducing, the heat regenerative system of drawing is identical.
10. forced circulation air preheating system according to claim 1 is characterized in that:
At least two outlet air channels of described hypomere air preheater are higher than described at least two gas approach.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201010601629.3A CN102012039B (en) | 2010-12-22 | 2010-12-22 | Forced circulation air preheat system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201010601629.3A CN102012039B (en) | 2010-12-22 | 2010-12-22 | Forced circulation air preheat system |
Publications (2)
| Publication Number | Publication Date |
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| CN102012039A true CN102012039A (en) | 2011-04-13 |
| CN102012039B CN102012039B (en) | 2014-01-22 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201010601629.3A Expired - Fee Related CN102012039B (en) | 2010-12-22 | 2010-12-22 | Forced circulation air preheat system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102345997A (en) * | 2011-09-29 | 2012-02-08 | 熊泽宇 | Dew point corrosion resistant method for flue gas heat exchanger |
| CN103148502A (en) * | 2011-12-06 | 2013-06-12 | 攀钢集团西昌钢钒有限公司 | Method for alleviating corrosion of boiler preheater |
| CN107860022A (en) * | 2017-11-28 | 2018-03-30 | 西安交通大学 | One kind becomes flue cross section tubular air preheater |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61217694A (en) * | 1985-03-22 | 1986-09-27 | Mitsubishi Heavy Ind Ltd | Composite type gas preheater |
| JPS62175513A (en) * | 1986-01-28 | 1987-08-01 | Babcock Hitachi Kk | Method for direct igniting and energizing of fine powder coal for boiler |
| CN2368001Y (en) * | 1999-04-23 | 2000-03-08 | 杨本洛 | Integrated heat-pipe type compound phase transition heat exchanger |
| CN200972137Y (en) * | 2006-11-15 | 2007-11-07 | 上海宁松热能环境工程有限公司 | Combined water thermal media air preheater |
| CN201434623Y (en) * | 2009-05-18 | 2010-03-31 | 上海泽宇机电设备制造有限公司 | Two-phase flow water heat medium heat exchange system |
| CN201582842U (en) * | 2009-11-17 | 2010-09-15 | 中国石油化工集团公司 | Combined air preheater |
| CN202002140U (en) * | 2010-12-22 | 2011-10-05 | 深圳中兴节能环保股份有限公司 | Forced circulation air preheating system |
-
2010
- 2010-12-22 CN CN201010601629.3A patent/CN102012039B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61217694A (en) * | 1985-03-22 | 1986-09-27 | Mitsubishi Heavy Ind Ltd | Composite type gas preheater |
| JPS62175513A (en) * | 1986-01-28 | 1987-08-01 | Babcock Hitachi Kk | Method for direct igniting and energizing of fine powder coal for boiler |
| CN2368001Y (en) * | 1999-04-23 | 2000-03-08 | 杨本洛 | Integrated heat-pipe type compound phase transition heat exchanger |
| CN200972137Y (en) * | 2006-11-15 | 2007-11-07 | 上海宁松热能环境工程有限公司 | Combined water thermal media air preheater |
| CN201434623Y (en) * | 2009-05-18 | 2010-03-31 | 上海泽宇机电设备制造有限公司 | Two-phase flow water heat medium heat exchange system |
| CN201582842U (en) * | 2009-11-17 | 2010-09-15 | 中国石油化工集团公司 | Combined air preheater |
| CN202002140U (en) * | 2010-12-22 | 2011-10-05 | 深圳中兴节能环保股份有限公司 | Forced circulation air preheating system |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102345997A (en) * | 2011-09-29 | 2012-02-08 | 熊泽宇 | Dew point corrosion resistant method for flue gas heat exchanger |
| CN102345997B (en) * | 2011-09-29 | 2012-11-28 | 熊泽宇 | Dew point corrosion resistant method for flue gas heat exchanger |
| CN103148502A (en) * | 2011-12-06 | 2013-06-12 | 攀钢集团西昌钢钒有限公司 | Method for alleviating corrosion of boiler preheater |
| CN103148502B (en) * | 2011-12-06 | 2015-06-03 | 攀钢集团西昌钢钒有限公司 | Method for alleviating corrosion of boiler preheater |
| CN107860022A (en) * | 2017-11-28 | 2018-03-30 | 西安交通大学 | One kind becomes flue cross section tubular air preheater |
| CN107860022B (en) * | 2017-11-28 | 2023-10-24 | 西安交通大学 | Variable flue section tubular air preheater |
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| CN102012039B (en) | 2014-01-22 |
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Granted publication date: 20140122 Termination date: 20191222 |