CN1079936C - 三扇区式空气预热装置的扇区板及密封装置 - Google Patents

三扇区式空气预热装置的扇区板及密封装置 Download PDF

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CN1079936C
CN1079936C CN96190702A CN96190702A CN1079936C CN 1079936 C CN1079936 C CN 1079936C CN 96190702 A CN96190702 A CN 96190702A CN 96190702 A CN96190702 A CN 96190702A CN 1079936 C CN1079936 C CN 1079936C
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air
plate
rotor
flue gas
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CN1163659A (zh
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W·C·高斯
T·G·麦格拉
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General Electric Technology GmbH
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ALSTHOM POWER Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23LSUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
    • F23L15/00Heating of air supplied for combustion
    • F23L15/02Arrangements of regenerators
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D19/00Regenerative heat-exchange apparatus in which the intermediate heat-transfer medium or body is moved successively into contact with each heat-exchange medium
    • F28D19/04Regenerative heat-exchange apparatus in which the intermediate heat-transfer medium or body is moved successively into contact with each heat-exchange medium using rigid bodies, e.g. mounted on a movable carrier
    • F28D19/047Sealing means
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00Combustion technologies with mitigation potential
    • Y02E20/34Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S122/00Liquid heaters and vaporizers
    • Y10S122/02Air heater - indirectly heated

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Air Supply (AREA)

Abstract

一种三扇区式空气预热器,其包括一次空气扇区和烟气扇区之间以及二次空气扇区和烟气扇区之间的扇区板,它具有较大尺寸,从而提供双径向密封。然而,一次和二次空气扇区之间的扇区板较小且只提供单径向密封。这样一个较小的扇区板减弱了通过空气预热器的压降,而所损失的只是两空气扇区之间的泄漏增加。一次和二次空气扇区之间的轴向密封可仍保持一双密封的尺寸。

Description

三扇区式空气预热装置的扇区板及密封装置
本发明的背景
本发明涉及采用双径向密封的三扇区旋转蓄热式空气预热器,且特别涉及到将预热器分成三个扇区的扇区板的布置及尺寸确定。
在大型蒸汽发生器,例如公用蒸汽发生器中烧煤,最普遍采用的工艺就是烧煤粉。对于烧煤粉,在制粉装置内通常利用空气对煤进行干燥、分级和输送。至制粉装置的空气称作一次空气,而残余燃烧空气称为二次空气。在能够进行点火前,煤一般都要进行干燥,且此干燥是采用一次热空气来完成的,随后该空气再将干燥后的煤粉送至炉子。
三扇区式空气预热器用于大型燃煤锅炉上,特别是希望采用冷的一次空气风机之处。该预热器是这样设计的,通过将预热器的空气侧分成两扇区,二次空气处于一单独的空气预热装置中,可以在这样的情况下对高压一次空气进行加热。
在空气加热器中提供密封装置,防止烟道气体与空气混合,这是众所周知的。这些密封可以包括在转动体和外壳之间围绕在转动体周围的轴向密封,和沿着构成转动体内格间的径向延伸隔板的上下边缘延伸的径向密封。沿隔板边缘的径向密封件与将空气预热器分成烟气扇区和空气扇区的扇区板呈摩擦闭合。这些径向密封件与扇区板的相互接合减少了烟气与空气的泄漏和混合。
为了尽可能实际地减少泄漏,通常均提供一双密封结构。在这种结构中,扇区板在尺寸上与两个转动体格间是相等的,使处在两个连续的径向延伸的转动体格间隔板上的径向密封同时与扇区板相互作用。这与单密封结构不同,单密封结构中扇区板在尺寸上只需与一个格间相等。双密封结构的问题是扇区板在空气预热器中占据或阻塞很大比例的流动面积。每个双密封扇区板所阻塞的流动面积是单密封扇区板的两倍。这就意味着通过空气预热器的压降提高了,或规格需要增大。
本发明的概要
本发明涉及一个三扇区式空气预热器,它包括在烟气和空气扇区之间是双径向密封,而在一次空气和二次空气扇区之间仅是单径向密封。更特指地,烟气扇区和两空气扇区之间的扇区板在尺寸上与两个转动体格间相等,从而提供双密封;而一次空气和二次空气扇区之间的扇区板在尺寸上只与一个格间相等,从而提供单密封。
附图的简要说明
图1是制粉装置和三扇区式空气预热器系统的示意图;
图2是三扇区旋转蓄热式空气预热器的总体立体图,为了表示上扇区板,拿走了一部分;
图3是现有技术中具有双径向密封的三扇区式空气预热装置转动体装置的简图;
图4是类似于图3的,但表示的是本发明扇区板的结构;
图5是一部分扇区板和转动体的横截面图,表示的是双密封结构;
图6是空气预热器一部分的平面图,表示轴向密封结构。
优选实施例的说明
附图中的图1给出了制煤粉装置12结合一个三扇区式空气预热器14的整体布置。煤自供料线16供入制粉装置12,而煤粉通过通道18供入一蒸汽发生装置(未示出)的喷煤嘴。来自蒸汽发生装置的烟气通过导管20供入空气预热器14,而后冷却后的烟气通入烟囱。一次燃烧空气由鼓风装置22吹入空气预热装置14,而且至少有一部分该一次燃烧空气供入空气预热器14中由烟气加热过的多个部分中的一个。导管24内加热过的一次空气可与来自导管26的未经加热的一次空气混合,在导管28内生成最终的一次空气供入制粉装置12。此一次空气对煤进行干燥,协助制粉装置内煤粉的分级,而且将煤粉输送到蒸汽发生装置。二次燃烧空气由鼓风机30供入空气预热器的另一扇区,在该处由烟气加热,而后直接供入蒸汽发生装置。这就是三扇区式空气预热器结合一制煤粉装置和蒸汽发生装置的全部传统布置和运转方式。
图2是根据本发明所构造的一空气预热器14的立体图。该空气预热器14包括一其中安装有转动体34的转动体外壳32。正如传统方式中那样,该转动体包括大量的热交换元件,它们自烟气流36吸收热,且将这些热传递给进来的空气流38。转动体34的转动方向如箭头40所示。为了更清楚地表示本发明,图2中未示出转动体34的内部结构,但是它应该包括径向隔板,它们形成各热交换元件的格间,以及包括径向密封,这将在下面进行说明。
转动体外壳32由扇区板42、44和46分成三个扇区。在转动体34的底部有相对应的扇区板。这三扇区为烟气扇区48、一次空气扇区50和二次空气扇区52。热烟气36由连接导管54(在图中部分剖切)导入扇区48,通过扇区48向下流动,将热量传递给转动体格间内的传热表面,然后通过导管连接装置56流出。由于这个热的传热表面随后转动通过一次和二次空气扇区50和52,该热量即传递给通过二次空气入口导管连接装置58和一次空气入口导管连接装置59(见图1)进入的空气,在导管连接装置区62内形成热的一次空气流60和在导管连接装置区66内形成热的二次空气流64。
图3和图4是表示空气预热器转动体和壳体的平面图,给出了扇区板与转动体的径向密封的关系。图3示出的是根据现有技术的扇区板,而图4示出的是本发明。这些图表示的是扇区板的横截面。隔板68将转动体分成格间70,其中包括传热表面,通常布置在适于装入格间的模件内。连接在这些隔板上缘和下缘的是径向密封72,其横截面示于图5。图5所示为双密封结构,其中扇区板44大到足以横跨两个格间,因此当转动体转动时两径向密封72总是与扇区板相互接合的。这亦可见于图3,其中现有技术的各扇区板42、44和46有着同样的尺寸且横跨两个格间。但是,如图4所示,根据本发明,一次空气扇区50和二次空气扇区52之间的扇区板46较小且只横跨一个格间,因此在某特定时刻只有一个径向密封72与扇区板46相接触。
采用双径向密封结构的原因是为了减少扇区间的泄漏。在三扇区式空气预热器上为减少泄漏而提供双径向密封时,有时难于满足对一次和二次空气低压降的要求,因为气流受到大尺寸扇区板的阻塞。在本发明中,扇区板46之一较小,因此提供了更大的通过转动体的空气流动面积和较小的压降。对于泄漏,人们最关心的是空气预热器的空气侧和烟气侧之间的泄漏。一次和二次空气之间的泄漏增加一些是可以允许的。在本发明中,在烟气扇区和两空气扇区之间仍保持双密封。例如,在一个具有50°一次空气扇区的三扇区式空气预热器中,如果用一个10°的一次空气扇区板46代替一个20°的扇区板,一次空气的压降将减少25%至30%。
尽管一次和二次空气扇区之间的泄漏不象空气扇区和烟气扇区之间的泄漏那么关键,而且甚至本发明有增大一次和二次空气扇区之间泄漏的倾向,但是人们还是希望使该处的泄漏保持最小。可以采取的一种方式是,在将一次和二次空气扇区之间的径向密封由双密封变为单密封的同时,其间的轴向密封仍保持双密封而不转变为单密封。此示于图6,该图所示为一空气预热器的一部分,给出了外壳32、转动体34、隔板68和扇区板44和46。安装于外壳32内部的是轴向密封板74和76(三个轴向密封板图中只示出两个),其沿转动体的整个高度延伸。安装在转动体上的是轴向密封,它与径向密封72相同或相似。在转动体转动时这些轴向密封与轴向密封板相接合,就如径向密封与扇区板相接合一样。当一次和二次空气扇区之间的扇区板46根据本发明减小尺寸只横跨一个格间时,相应的轴向密封板76可如图所示保持双密封的尺寸,因此总是横跨两个轴向密封件。

Claims (2)

1.一种用于将热从流经的烟气流(36)传递到进来的空气流(38)的空气预热器(14),包括:
一个转动体外壳(32);
一个位于所述转动体外壳(32)的转动体(34),具有多个径向延伸的隔板(68)和多个径向密封(72),隔板在所述转动体(34)上形成格间(70),每个径向密封(72)沿对应隔板(68)的顶部轴向边缘径向延伸;
在所述转动体外壳(32)两轴向端的三个扇区板(42,44,46)将垂直于转动体轴线看的转动体外壳的横截面分成了烟气扇区(48),一次空气扇区(50)和二次空气扇区(52),所述烟气扇区(48)和所述一次空气扇区(50)之间的扇区板(42)以及所述烟气扇区(48)和所述二次空气扇区(52)之间的扇区板(44)具有在所述转动体(34)围绕其轴线于所述转动体外壳(32)内转动的所有时间与两个所述径向密封(72)接合的尺寸,所述一次和二次空气扇区(50,52)之间的扇区板(46)具有在任何特定时间只与所述径向延伸的顶部轴向边缘密封的其中一个接合的尺寸。
2.如权利要求1所述的空气预热器,还包括围绕所述转动体(34)的外侧间隔布置的轴向密封和装在所述转动体外壳(32)的内侧所述扇区板(42,44,46)之间用于与所述轴向密封接合的轴向密封板(74,76),其中每个所述轴向密封板(74,76)具有在所有时间与两个所述轴向密封接合的尺寸。
CN96190702A 1995-06-29 1996-06-12 三扇区式空气预热装置的扇区板及密封装置 Expired - Lifetime CN1079936C (zh)

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US08/496,734 US5915339A (en) 1995-06-29 1995-06-29 Sector plate and seal arrangement for trisector air preheater
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AU699734B2 (en) 1998-12-10
AU6172396A (en) 1997-01-30
US5915339A (en) 1999-06-29
EP0777840B1 (en) 1999-08-11
DE69603689T2 (de) 2000-04-06
JPH09508697A (ja) 1997-09-02
KR100429939B1 (ko) 2004-07-31
BR9606452A (pt) 1998-07-14
CA2195765C (en) 2003-04-01
JP2782018B2 (ja) 1998-07-30
ZA965471B (en) 1997-01-27
TW307818B (zh) 1997-06-11
DE69603689D1 (de) 1999-09-16
IN189244B (zh) 2003-01-18
CN1163659A (zh) 1997-10-29
ES2137706T3 (es) 1999-12-16
KR970705725A (ko) 1997-10-09
CA2195765A1 (en) 1997-01-16
WO1997001733A1 (en) 1997-01-16
EP0777840A1 (en) 1997-06-11

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