化工原理课程设计柴油原油换热器设计说明书.doc

化工原理课程设计柴油换热器设计说明书设计者：班级：过控132组长：成员：学生姓名：日期 ：2015年9月4日 指导教师： 目录一设计说明书································································3二设计条件及主要物性的确定···················································31定性温度的确定·························································3 2流体有关物性···························································3三. 确定设计方案······························································41 选择换热器的类型······················································42流程安排·······························································4四 估算传热面积·····························································41. 传热器的热负荷·······················································42. 平均传热温差·························································43. 传热面积估算·························································4五 工程结构尺寸·····························································51. 管径和管内流速························································52. 管程数和传热管数······················································53. 平均传热温差校正和壳程数··············································54. 传热管排列和分程方法··················································55. 壳程内径······························································66. 折流板································································67. 其他附件······························································68. 接管··································································6六换热器核算·································································7 1.热流量核算·······························································7 （1）壳程表面传热系数···················································7 （2）管程表面传热系数···················································7 （3）污垢热阻和管壁热阻·················································8 （4）传热系数K·························································8 （5）传热面积裕度·······················································8 2.壁温核算·································································93.换热器内流体的流动阻力···················································9 （1）管程流动阻力························································9 （2）壳程流动阻力·······················································10七换热器主要工艺结构尺寸和计算结果表·······································11八设备参考数计算···························································121.壳体壁厚·······························································12 2.接管法兰·······························································123.设备法兰·······························································12 4.封头管箱·······························································12 5.设备法兰垫片（橡胶石棉板）··············································126.管法兰用垫片···························································137.管板····································································138.支垫（鞍式支座）··························································139.设备参数总表···························································13九设计总结·································································15十.主要符号说明 ····························································16十一.参考文献································································17一、设计说明书1.设计任务书和设计条件 原油44000kg/h由70°C被加热到110°C与柴油换热，柴油流量34000kg/h，柴油入口温度175°C，出口温度127。已知两则污垢热阻为0.0002·C/W,管程与壳程两则降压小于或等于0.3at，热阻损失5%，初设k=250w/ m2·°C。二、设计条件及主要物性参数2.1设计条件由设计任务书可得设计条件如下表：数参类型体积流量（标准kg/h）进口温度（）出口温度（）操作压力（Mpa）设计压力（Mpa）柴 油（管内）34000175 1271.11.2原油（管外）4400070110 0.30.4注：要求设计的冷却器在规定压力下操作安全，必须使设计压力比最大操作压力略大，本设计的设计压力比最大操作压力大0.1MPa。2.2确定主要物性数据2.2.1定性温度的确定根据流体力学（上）P177，公式（4-109），热流量为 Qc = Wc Cpc(T1T2) ×1.05 =44000×2.2×（14842）×1.05=1.13×106kJ/h = 1.13×106 W 管程柴油的定性温度为 壳程原油的定性温度为 2.2.2流体有关物性数据根据由上面两个定性温度数据，查阅参考书可得原油和柴油的物理性质。运用内插法（公式为 ）,可得壳程和管程流体的有关物性数据。原油在90，1.2MPa下的有关物性数据如下：物性密度i（kg/m3）定压比热容cpi kJ/(kg)粘度i（Pa·s）导热系数i（W·m-1·-1）原油 8152.26.65×10-3 0.128 柴油在151的物性数据如下：物性密度o（kg/m3）定压比热容cpo kJ/(kg)粘度o（Pa·s）导热系数o（W·m-1·-1）柴油715 2.480.64×10-30.133三、确定设计方案3.1 选择换热器的类型由于温差较大和要便于清洗壳程污垢，对于油品换热器，以采用Fe系列的浮头式列管换热器为宜。采用折流挡板，可使作为被冷却的原油易形成湍流，可以提高对流表面传热系数，提高传热效率。3.2 流程安排柴油温度高，走管程课减少热损失，原油黏度较大，走壳程在较低的Re数时即可达到湍流，有利于提高其传热膜系数。四、估算传热面积4.1热流量4.2平均传热温差= (0,1atm)=614.3传热面积由于管程气体压力较高，故可选较大的总传热系数。初步设定设Ki=250 W·m-2·-1。根据化工单元过程及设备课程设计P44，公式3-8，则估算的传热面积为 m2五工程结构尺寸5.1管径和管内流速选用25×2.5mm的传热管(碳钢管)；由传热传质过程设备设计P7表13得管壳式换热器中常用的流速范围的数据，可设空气流速ui1m/s，用u i计算传热膜系数，然后进行校核。5.2管程数和传热管数依化工单元过程及设备课程设计P46，公式3-9可依据传热管内径和流速确定单程传热管数(根)按单程管计算，所需的传热管长度为m按单管程设计，传热管过长，宜采用多管程结构。现取传热管长 l= 7 m ，则该换热器管程数为Np=L / l=22.5/74（管程）传热管总根数 N = 42×4= 168 （根）。5.3 平均传热温差校正及壳程数依化工单元过程及设备课程设计P46，公式3-13a和3-13b，平均传热温差校正系数R1.2P0.381 依传热传质过程设备设计P16，公式3-13，温度校正系数为 0.92依传热传质过程设备设计P16，公式3-14，平均传热差校正为tm=×tm =61×0.92=56.12( )由于平均传热温差校正系数大于0.8，同时壳程流体流量较大，故取单壳程合适。5.4 传热管的排列和分程方法采用组合排列法，即每程内均按旋转45°正四边形排列，其优点为管板强度高，流体走短路的机会少，且管外流体扰动较大，因而对流传热系数较高，相同的壳程内可排列更多的管子。查化工单元过程及设备课程设计P50，表3-7 管间距，取管间距：t 1.25d=1.25x25=32 mm 。由化工单元过程及设备课程设计P50，公式3-16，隔板中心到离其最近一排管中心距离S=t/2+6=32/2+6=22 mm取各程相邻管的管心距为44mm。5.5 壳体内径 采用多管程结构，取管板利用率=0.7，由化工单元过程及设备课程设计P51，公式3-20，得壳体内径为Di =1.05t=1.05×32×=520 mm , 圆整后取Di =600mm。5.6折流板采用弓形折流板，取弓形折流板圆缺高度为壳体内径的25%，则切去的圆缺高度为h=0.25×600=150 mm ，故可取h=150 mm。取折流板间距B=0.3Di，则B=0.3×600=180 mm。折流板数 NB=1=138 块折流板圆缺面水平装配。5.7其他附件直径为12mm的拉杆4根。5.8接管（1）壳程流体进出口接管 取接管内液体流速u1=0.5m/s, =0.195(m)圆整后取管内直径为200mm.(2) 管程流体进出口接管 取接管内液体流速u2=1m/s,圆整后取管内直径为150mm六换热器核算6.1热量核算6.1.1壳程表面流传热系数 对于圆缺形折流板，可采用克恩公式。由化工单元过程及设备课程设计P53，公式3-22，得ho = 其中： 粘度校正为=1.05当量直径，管子为四边形角形排列时，依化工单元过程及设备课程设计P53，公式3-23a得de0.027 m壳程流通截面积，由化工单元过程及设备课程设计P54，公式3-25，得So = BD(1)=0.18×0.6×（1）0.023625 m2壳程冷却水的流速及其雷诺数分别为uo =0.635 m/sReo1556普朗特准数（<传热传质过程设备设计>P26，公式1-43）Pr =114.29因此，壳程水的传热膜系数ho为ho = =668 W/(m2·)6.1.2管程表面流传热系数由化工单元过程及设备课程设计P55，公式3-22，3-33,得hi = 0.023Re0.8Pr0.3其中：管程流通截面积Si =0.02637 m2管程空气的流速及其雷诺数分别为ui =0.5 m/sRe11172>10000普兰特准数Pr =11.93因此，管程空气的传热膜系数hi为hi=0.023×111720.8×11.930.3×=557.3W/(m2·)6.1.3污垢热阻和管壁热阻l 冷却水侧的热阻Rso0.0002m2··W-1l 热空气侧的热阻Rsi0.0002m2··W-1l 碳钢的导热系数50W·m-1·-16.1.4总传热系数Ki因此，依化工单元过程及设备课程设计P53，公式3-21 Rso 0.0002解得：236 W/ (m2·) 6.1.5 传热面积裕度依化工单元过程及设备课程设计P56，公式3-35：QiSitm得：SiQi/(tm)78.49 m2该换热器的实际传热面积SpSp=3.14×0.05×7×168=92.316 m2依化工单元过程及设备课程设计P56，公式3-36该换热器的面积裕度为=17.6%6.2 壁温核算 因管壁很薄，且管壁热阻很小，故管壁温度可按化工单元过程及设备课程设计P77，公式3-42计算。由于传热管内侧污垢热阻较大，会使传热管壁温升高，降低了壳体和传热管壁温之差。但在操作早期，污垢热阻较小，壳体和传热管间壁温差可能较大。计算中，应按最不利的操作条件考虑。因此，取两侧污垢热阻为零计算传热管壁温。于是按式3-42有式中，冷流体的平均温度tm和热流体的平均温度Tm分别按化工单元过程及设备课程设计P77，公式3-44、3-45计算Tm=0.4×175+0.6×125=146tm=0.4×110+0.6×70=86 hc = ho = 668 W/ (m2·) hh = hi = 557W/ (m2·)传热管平均壁温=113.6 壳体壁温，可近似取为壳程流体的平均温度，即T=90 壳体壁温和传热管壁温之差为 t=113.690 =23.6 该温差不大，不需要建立温度补偿装置。6.3换热器内流体的流动阻力(压降)6.3.1管程流动阻力由，传热管相对粗超度为0.01，查莫狄图得，流速u=0.05m/s, (pa)(pa)总压降：pi（p1+p2）Ft Ns Np（1188.68+268.125）×1.5×1×48740Pa < 9800 Pa（符合设计要求） 其中， Ft为结垢校正系数，取1.5；Ns为串联壳程数，取1；Np为管程数，取4。 6.3.2壳程流动阻力：由化工单元过程及设备课程设计P58，公式3-51,3-52，得： 流体横过管束的压降：其中：F=0.4fo=5.0×1556-0.228=0.9358NB=38uo=0.635 m/spO=0.4×0.9358×15.42×(38+1)×(815×0.6352)/2 36989 PapINB（3.5）38×（3.5）×(815×0.6352)/218107Pa总压降：po（p1p2）Fs Ns（36989+18107）×1.15×163360.4Pa 其中，Fs为壳程压强降的校正系数，对于液体取1.15；Ns为串联的壳程数，取1。七.换热器主要结构尺寸和计算结果表参数管程壳程流量，kg/h3400044000物性操作温度，175/12770/110定性温度，15190流体密度，kg/m3715815定压比热容，kj/(kg.k)2.482.2黏度，pa.s传热系数，W/（m2·）0.1330.128普朗特数11.93114.2设备结构参数形式浮头式台数1壳体内径，mm600壳程数1管径，mm管心距，mm32管长，mm7000管子排列正方形旋转45°管数目，根168折流板数38传热面积，92.316折流板间距，mm180管程数4材质碳钢主要计算结果管程壳程流速，m/s0.50.634表面传热系数，W/（m2·）668557.3污垢系数，m2·K/W0.00020.0002阻力降，Pa0.00870.0633热流量，kw1130传热温差，k23.6传热系数，W/（m2·）236裕度17.6八、设备参数计算1.壳体壁厚 由Po1.6 MPa， Di600mm，对壳体与管板采用单面焊，焊接接头系数0.9,腐蚀裕度C=1mm， t=112MPa +C+1=5.8mm圆整后取8mm 2. 接管法兰Dg管子平焊法兰螺栓焊缝dHSDD1D2fbd重量（kg）数量直径KH1001084215180158326184.88M16563.设备法兰 Dg管子平焊法兰螺栓焊缝dHSDD1D2fbd重量（kg）数量直径KH60063098407707205504180.320M3610114.封头管箱封头：以外径为公称直径的椭圆形封头公称直径Dg曲面高度h1直边高度h2内表面积F容积v（m3）600150400.4640.396 5.设备法兰垫片（橡胶石棉板）公称直径Dg垫片内径d公称压力F(m2)垫片外径D60061516655 6.管法兰用垫片法兰公称压力Mpa介质温度密封面型式垫片名称材料油品1.6200光滑式耐油橡胶石棉垫片耐油橡胶石棉板 7. 管板管板厚度35mm，长度300mm，材料为16MnR。 8. 支垫（鞍式支座）公称直径Dg每个支座允许负荷tb1LBlK1bm重量（kg）60036.81805501202604209022026.39. 设备参数总表序号图号标准名称数量材料单重（kg）总量（kg）1LNQ-001-3前瑞管箱1组合件84.52HG20592法兰PL100-1.0 RF2Q235-B2.625.243GB8163-87接管108X5 L=1602Q235-B4LNQ-001-2折流板 29Q235-A7.5217.55筒体DN127X4.51Q235-B2786LNQ-001-2拉杆4Q235-B4.216.87GB/T6170螺母M1684级0.040.328LNQ-001-3法兰120II879垫片642/600 S=34石棉橡胶板0.310JB/T4701-2000法兰-FM600-1.01Q235-B40.811筒体DN600X8 L=1401Q235-B16.812JB/T 4746-2002封头EHA 600X51Q235-B1713GB/T14976换热管25X2.5，L=60001560Cr18Ni93.4530.414JB/T4712-92支座 500-S2Q235-A/Q235-B26.315JB/4701-2000法兰-FM500-1.01Q235-B29.516SYJ11-65垫片2橡胶板0.150.317LNQ-001-3防松吊耳2Q235-B0.080.1618LNQ-001-2管板116MnR6519GB/T6170螺母 M201286级0.0648.220JB/T4707螺栓M20x150-A626.8级0.3320.46 九、设计总结两周的化工原理课程设计即将结束，我们小组设计的是柴油原油换热器，虽然时间不长，但我们却从中学到了很多知识。加深和巩固了上学期所学的化工原理这虽然刚开始会感到无从下手，很多所学的知识也有些生疏。但通过佟白老师的细心讲解，我们大家共同合作，一起讨论研究，通过一周的翻阅资料,查找公式,设计计算,使我对换热器有了进一步的了解,对传热的具体过程有了深刻的认识.尤其是从最初的无从下手到现在的可根据传热的不同而选择不同的换热器.另外,我对于换热器的用途也有了更多的认识.。最后我们顺利的完成了整个设计。在佟白老师的细心讲解和指导下独立完成了本次课程设计，通过这次的锻炼,为我今后的学习工作做了良好的开端.这次的课程设计对我今后的生活产生巨大的影响也会终生难忘的. 通过这初次的课程设计使我们深刻的了解了化工原理这门课的主要内容以及对将来工作的深远影响。 在此，感谢学院为我们提供了一个锻炼自我，学习与历练的机会，感谢佟白老师耐心，认真的辅导，使我们的设计得以顺利完成。十、 主要符号说明原油的定性温度T柴油定性温度t原油密度o柴油密度i原油定压比热容cpo柴油定压比热容cpi原油导热系数o柴油导热系数i原油黏度o柴油黏度i原油热流量Wo柴油流量热负荷Qo平均传热温差总传热系数管程雷诺数温差校正系数管程、壳程传热系数 初算初始传热面积A估传热管数初算实际传热面积A管程数壳体内径D横过中心线管数折流板间距B管心距t折流板数NB接管内径 管程压力降当量直径壳程压力降面积裕度H十一、参考文献【1】申迎华，郝晓刚.化工原理课程设计.北京，化学工业出版社，2009【2】姚玉英等.化工原理（上）.天津，天津大学出版社，2005【3】任晓光.化工原理课程设计指导.北京，化学工业出版社，2009【4】贾绍义.柴诚敬.化工原理课程设计.天津，天津大学出版社，2002【5】袁文.刘岩.化工制图.哈尔滨，哈尔滨工程大学出版社，2010【6】钟理, 伍钦，马四朋. 化工原理（上）. 北京，化学工业出版社，2008.8.【7】材料与零部件（上）. 上海科学技术出版社. 1982.7.【8】钱颂文. 换热器设计手册，北京，化学工业出版社，2002.8【9】匡国柱. 化工单元过程及设备课程设计. 北京，化学工业出版社，2002【10】陈锦昌. 计算机工程制图. 广州，华南理工大学出版社，2006.8.【11】郑津洋，董其伍，桑芝富. 过程设备设计. 北京，化学工业出版社，2009.1.【12】赵军. 化工设备机械基础. 北京，化学工业出版社. 2000.