毕业设计中压燃贫煤煤粉锅炉设计

COLLEGEOFLIGHTINDUSTRY,HEBEIUNITEDUNIVERSITY本设计是针对75t/h的中压燃贫煤煤粉锅炉进行的。本设计是在现场参观的基础上，通过查阅大量的文献和资料，结合所学专业知识，对锅炉进行了总体布置和全面的热力计算。目的是掌握锅炉设计的一般计算方法及计算步骤。锅炉总体结构采用单锅筒Π型布置,上升烟道为燃烧室和凝渣管两部分，水平烟道内布置两级悬挂对流过热器，垂直下行烟道中布置两级省煤器和两级管式空气预热器。锅炉炉膛全部布满光管水冷壁。对流过热器分两级布置，由悬挂式蛇形管束组成，两级过热器之间装有锅炉自制喷水减温装置，省煤器和空气预热器分别采用两级配合布置。本锅炉采用四角切圆燃烧方式与分级配风的直流煤粉燃烧器。最后根据计算结果用CAD绘制锅炉总体图及燃烧器部件图。关键词:贫煤；中压；热力计算；四角切圆燃烧ABSTRACT Thedesignis75t/hofmediumpressurepulverizedcoalboilersoftheoflean-coal.Thisdesignisonthebaseofvisitingthepowerplantandreferringlotsofliteraturesandinformation,combinedwithprofessionalknowledgelearned,theoveralllayoutoftheboilerandcomprehensivethermodynamiccalculation.Purposeistomastertheboilerdesignandcalculationofthegeneralmethodsteps.TheoverallstructureofthesingledrumboilerΠ-typelayout,increasethefluepipeforthecombustionchamberandcondensateresidueoftwoparts,theleveloffluegasconvectionsuper-heaterarrangementoftwohanging,verticalflueinthearrangementoftwodownandtwo-tubeeconomizerairpreheater.Allfullofboilerfurnacewaterwalltubes.Convectionsuper-heaterarrangedintwolevels,snake-liketubesformedbythehanging,twowerefittedbetweentheboilersuper-heaterspraymadebytemperaturedevices,Economizersusetwotielayout.boilercombustionusesfourcornertangentiallycombustionandthedirectcurrentburnerofdividedgradationdistributeair.Finally,accordingtothecalculatedresult,theboilerentiredrawingandburnerdrawingarecompletedwithAutoCAD.Keywords:lean-coal,medium-pressure,heattransfer-calculation,fourcornertangentiallycombustion目录引言 .1885表22下级（低温）空气预热器的传热计算序号名称符号单位公式及计算结果1入口烟温℃查表18239.93表22（续）序号名称符号单位公式及计算结果2入口烟焓查表183754.13空气入口温度℃查表4304空气入口焓查表4300.415空气出口温度℃查表201606空气出口焓查表201611.37平均空气温度℃958平均空气焓955.849出口空气过量系数-+1.0310空气吸热量1369.911烟气出口焓2401.812烟气出口温度℃查表2（=1.33）148.6213平均烟温℃194.2814烟气体积查表2（=1.33）10.35715烟气流速7.96116相对管长-77.02717水蒸气容积份额-查表2（=1.33）0.0522表22（续）序号名称符号单位公式及计算结果18烟气侧放热系数查图12-825.8419空气流速4.12520空气侧放热系数查图12-752.6221利用系数-查表12-90.7522传热系数K12.8323入口温压℃79.93724出口温压℃118.6225逆流温压℃8226大温降℃13027小温降℃91.31728参数P-0.43529参数R-1.42330温压修正系数-查图12-40.9231温压℃75.4432传热量1382.033误差％-0.887表23热力计算汇总表序号名称符号单位炉膛凝渣管第二级过热器第一级过热器上级省煤器上级空气预热器下级省煤器下级空气预热器1烟气出口温度1013.8950750.4580.4451.7320.5239.9148.62介质进口温度254.7254.7315259.2150160128.4303介质出口温度254.7254.7450361.5195.03421501604介质平均温度--15.1212.391.0844.8750.684.1255烟气平均温度-5.23110.579.2297.5049.7155.8767.9616平均温压-727.2462.3352.0341.2114.886.6275.447传热系数-54.1668.3951.1564.6116.8149.4712.838受热面积-58.09179.31326.25196.892339.66456.473326.84表Ⅰ-23（续）序号名称符号单位炉膛凝渣管第二级过热器第一级过热器上