CN109611831A - 一种褐煤干馏循环流化床锅炉 - Google Patents

一种褐煤干馏循环流化床锅炉 Download PDF

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CN109611831A
CN109611831A CN201811520334.6A CN201811520334A CN109611831A CN 109611831 A CN109611831 A CN 109611831A CN 201811520334 A CN201811520334 A CN 201811520334A CN 109611831 A CN109611831 A CN 109611831A
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destructive distillation
lignite
cylinder
separator
distillation cylinder
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唐跃
宋平
王志平
刘定宇
陈帅男
刘庆
何军
文爱兰
姜红秀
刘启
雍漫江
王楚
陈鹏
李劼
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XIANGTAN BOILER CO Ltd
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XIANGTAN BOILER CO Ltd
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Priority claimed from CN201711340851.0A external-priority patent/CN108087870A/zh
Priority claimed from CN201711343120.1A external-priority patent/CN108036307A/zh
Priority claimed from CN201711340844.0A external-priority patent/CN107859992A/zh
Priority claimed from CN201711340853.XA external-priority patent/CN107940447A/zh
Application filed by XIANGTAN BOILER CO Ltd filed Critical XIANGTAN BOILER CO Ltd
Publication of CN109611831A publication Critical patent/CN109611831A/zh
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B31/00—Modifications of boiler construction, or of tube systems, dependent on installation of combustion apparatus; Arrangements of dispositions of combustion apparatus
    • F22B31/08—Installation of heat-exchange apparatus or of means in boilers for heating air supplied for combustion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C10/00—Fluidised bed combustion apparatus
    • F23C10/02—Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed
    • F23C10/04—Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone
    • F23C10/08—Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone characterised by the arrangement of separation apparatus, e.g. cyclones, for separating particles from the flue gases
    • F23C10/10—Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone characterised by the arrangement of separation apparatus, e.g. cyclones, for separating particles from the flue gases the separation apparatus being located outside the combustion chamber
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
    • C10B49/00—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated
    • C10B49/02—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated with hot gases or vapours, e.g. hot gases obtained by partial combustion of the charge
    • C10B49/04—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated with hot gases or vapours, e.g. hot gases obtained by partial combustion of the charge while moving the solid material to be treated
    • C10B49/08—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated with hot gases or vapours, e.g. hot gases obtained by partial combustion of the charge while moving the solid material to be treated in dispersed form
    • C10B49/10—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated with hot gases or vapours, e.g. hot gases obtained by partial combustion of the charge while moving the solid material to be treated in dispersed form according to the "fluidised bed" technique
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C10/00—Fluidised bed combustion apparatus
    • F23C10/18—Details; Accessories
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C10/00—Fluidised bed combustion apparatus
    • F23C10/18—Details; Accessories
    • F23C10/24—Devices for removal of material from the bed
    • F23C10/26—Devices for removal of material from the bed combined with devices for partial reintroduction of material into the bed, e.g. after separation of agglomerated parts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J15/00—Arrangements of devices for treating smoke or fumes
    • F23J15/02—Arrangements of devices for treating smoke or fumes of purifiers, e.g. for removing noxious material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J15/00—Arrangements of devices for treating smoke or fumes
    • F23J15/06—Arrangements of devices for treating smoke or fumes of coolers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23L—SUPPLYING 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
    • F23L15/00—Heating of air supplied for combustion
    • F23L15/02—Arrangements of regenerators
    • 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

Abstract

本发明提供一种褐煤干馏循环流化床锅炉，炉膛连分离器，分离器连干馏筒，所述干馏筒围绕自身轴心作旋转运动，干馏筒连炉膛；启动煤进入炉膛燃烧，燃烧后的烟气进入分离器，分离器分离出的返料灰进入干馏筒内，与干馏筒内的褐煤混合并进行干馏，干馏温度为600~650℃，在干馏筒褐煤出口和返料灰进口通道中均设U形输送阀，干馏后的褐煤进入炉膛燃烧。是一种燃烧褐煤的锅炉。

Description

一种褐煤干馏循环流化床锅炉
技术领域
本发明涉及一种锅炉，尤其是一种褐煤干馏循环流化床锅炉。
背景技术
褐煤，又名柴煤，英文：Lignite (coal)；brown coal ；wood coal，是煤化程度最低的矿产煤。一种介于泥炭与沥青煤之间的棕黑色、无光泽的低级煤。化学反应性强，在空气中容易风化，不易储存和运输，燃烧时对空气污染严重。但是由于优质煤越来越少，褐煤已成为我国主要使用的煤，但由于褐煤的煤化程度太低，导致燃烧时会有大量的黑灰飘在空中，如果不经过处理和提炼，大量使用褐煤将导致我国雾霾问题日益严重。
褐煤提质是指通过物理或化学方法提高褐煤质量的过程。褐煤在一定温度下经过脱水和热分解作用后除去大部分水外还伴有含氧官能团的脱除，使煤的组成和结构发生变化，变得更为致密。具有类似烟煤的性质。燃烧过程中减少了水汽蒸发而消耗的热量，提高了褐煤热值和燃烧效率。怎样使褐煤干馏工艺降低成本，并使提质后的褐煤就地燃烧转换成清洁的电能是关键。
发明内容
本发明的目的在于提供一种褐煤干馏循环流化床锅炉。
实施本发明所采用的技术方案是，炉膛连分离器，分离器连干馏筒，所述干馏筒围绕自身轴心作旋转运动，干馏筒连炉膛；启动煤进入炉膛燃烧，燃烧后的烟气进入分离器，分离器分离出的返料灰进入干馏筒内，与干馏筒内的褐煤混合并进行干馏，干馏温度为600~650℃，在干馏筒褐煤出口和返料灰进口通道中均设U形输送阀，干馏后的褐煤进入炉膛燃烧。
进一步，干馏筒与水平面的夹角大于0度，小于或等于90度。
进一步，U形输送阀为密封输送，输送介质采用蒸汽或氮气。
本发明的有益效果在于，褐煤干馏与循环流化床锅炉结合，降低了褐煤干馏的成本，又使褐煤就地燃烧，锅炉产生高参数蒸汽再通过汽轮发电机转换成清洁的电能，实现了褐煤的高效利用；高温返料灰粒度细，有利于与褐煤的混合干馏，可以大大降低褐煤干馏成本，综合效益很高。
附图说明
图1是本发明流程图。
图2是本发明主视示意图。
图3是本发明侧视示意图。
图4是干馏筒、旋风分离器位置关系示意图。
图5是U形输送阀结构示意图。
具体实施方式
参见图1至图4，炉膛1连旋风分离器6，旋风分离器6连干馏筒2，干馏筒2连炉膛1；启动煤进入炉膛1燃烧，燃烧后的烟气进入旋风分离器6，旋风分离器6分离出的返料灰通过返料器5a进入干馏筒2内，与干馏筒2内的褐煤混合并进行干馏，干馏温度为600-650℃，干馏后的褐煤进入炉膛1燃烧，维持锅炉的正常运行。
旋风分离器6是卧式或立式绝热旋风分离器；干馏筒2的褐煤出口连返料器5b，之后，通过返料管13进入炉膛1，干馏筒2采用卧式圆筒结构，其倾角大于0度，小于或等于90度。干馏后的褐煤至返料器5b，再至炉膛1内燃烧。锅炉点火时从启动燃料入口4输入所需启动燃料，滚筒输送机3输送启动燃料，例如优质无烟煤。
褐煤干馏主要工艺为：利用循环流花床锅炉850~900℃高温循环返料灰和褐煤在干馏炉内混合后进行低温600~650℃干馏，褐煤干馏后再返回炉膛内进行循环燃烧。
炉膛1内的燃料，包括干馏后的褐煤，在流态化状态下燃烧，并与炉膛1内水冷壁受热面进行热交换进入汽包12，炉膛1出口布置立式或卧式高温旋风分离器6，烟气离开炉膛1并夹带大量物料颗粒，烟气经过高温旋风分离器6之后，绝大部分固体物料被旋风分离器6分离下来，和干馏筒2内褐煤进行混合干馏后，经返料器5b返回炉膛1继续燃烧。烟气从旋风分离器6出来后进入尾部烟道，依次经过高低温过热器9，高、低温省煤器10、一二次风空气预热器11、除尘脱硫器20，最后从烟囱21排出。
一次风机18b风经过空气预热器11后，形成锅炉一次风16进入风室15；二次风机18b的风经过空气预热器11后，形成锅炉二次风14进入炉膛1。
原料煤仓7的褐煤进入干馏筒2，干馏筒2的烟气用旋风除尘器8进行分离，其高温风进入冷却回收系统，例如过热器9、省煤器10、空气预热器11或者其他热交换机。
返料器5a、5b采用非机械式的“U”形输送阀，进行循环灰的输送与密封，旋风分离器6出口高温循环灰的温度约850~900℃，与褐煤混合后温度约600-650度，在圆筒内滚动混合换热进行干馏。干馏筒2进出口均布置有非机械式的“U”形输送阀，输送介质采用蒸汽或惰性气体，保证干馏炉内无空气，确保系统安全稳定运行。褐煤干馏机进口和出口均设置“U”形输送阀，干馏筒进口“U”形输送阀连接旋风分离器6的料腿，干馏筒出口“U”形输送阀连接循环流化床锅炉炉膛1，“U”形输送阀是可靠的密封输送装置，常规循环流化床锅炉采用高压罗茨风机流化输送，输送介质为空气，而褐煤干馏机内有可燃气体，为防止爆炸，“U”形输送阀，输送介质采用蒸汽或惰性气体氮气进行流化输送，从而保证干馏炉内无空气，确保锅炉燃烧安全稳定运行。
参见图5，本实施例“U”形输送阀即返料器5a、5b，也可以称返料阀、回料器或回料阀，其输送端的位置高，其目标容器端位置低，结构呈“U”形，加上松动风22，将高温固体物料稳定的送回压力较高的燃烧室内，并且保证气体反窜进入旋风分离器6或者干馏筒2的量为最小。
“U”形输送阀保证物料稳定输送入炉膛，同时防止烟气反串。在立管与炉膛压差的作用下将物料送入炉膛。当外循环减弱时，立管与炉膛压差小，返料量减少，具有自平衡的作用；立管内物料高度变化减小（即维持一定的料位高度），防止烟气反串。具有自平衡作用，自动调节返料量，无需人工调节。

Claims (3)

1.一种褐煤干馏循环流化床锅炉，其特征在于，炉膛连分离器，分离器连干馏筒，所述干馏筒围绕自身轴心作旋转运动，干馏筒连炉膛；启动煤进入炉膛燃烧，燃烧后的烟气进入分离器，分离器分离出的返料灰进入干馏筒内，与干馏筒内的褐煤混合并进行干馏，干馏温度为600~650℃，在干馏筒褐煤出口和返料灰进口通道中均设U形输送阀，干馏后的褐煤进入炉膛燃烧。
2.根据权利要求1所述的一种褐煤干馏循环流化床锅炉，其特征在于，干馏筒与水平面的夹角大于0度，小于或等于90度。
3.根据权利要求2所述的一种褐煤干馏循环流化床锅炉，其特征在于，U形输送阀为密封输送，输送介质采用蒸汽或氮气。
CN201811520334.6A 2017-12-14 2018-12-13 一种褐煤干馏循环流化床锅炉 Pending CN109611831A (zh)

Applications Claiming Priority (10)

Application Number Priority Date Filing Date Title
CN201711340851.0A CN108087870A (zh) 2017-12-14 2017-12-14 一种带有输送阀的干馏循环流化床锅炉
CN201721747458 2017-12-14
CN2017113408440 2017-12-14
CN2017217474589 2017-12-14
CN201711343120.1A CN108036307A (zh) 2017-12-14 2017-12-14 一种滚筒输送式干馏循环流化床锅炉
CN2017113431201 2017-12-14
CN2017113408510 2017-12-14
CN201711340844.0A CN107859992A (zh) 2017-12-14 2017-12-14 一种干馏循环流化床锅炉
CN201711340853X 2017-12-14
CN201711340853.XA CN107940447A (zh) 2017-12-14 2017-12-14 干馏循环流化床锅炉

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