柴油原油換熱器設(shè)計(jì)說明書

1、齊齊哈爾大學(xué) 化工原理課程設(shè)計(jì)柴油換熱器化工原理課程設(shè)計(jì)柴油換熱器設(shè)計(jì)說明書設(shè)計(jì)者：班級：過控132組長：吳世杰成員：劉云杰 李亞芳 鄭仕業(yè) 刁昌東 王宇 學(xué)生姓名：吳世杰日期 ：2015年9月4日 指導(dǎo)教師：佟白 目錄一設(shè)計(jì)說明書······························

2、3;·································3二設(shè)計(jì)條件及主要物性的確定··············&#

3、183;····································31定性溫度的確定············

4、;·············································3 2流體有關(guān)物性···&#

5、183;·················································&#

6、183;·····3三. 確定設(shè)計(jì)方案··········································

7、3;···················41 選擇換熱器的類型·····························

8、;·························42流程安排························

9、;·······································4四 估算傳熱面積·········&#

10、183;·················································&#

11、183;·41. 傳熱器的熱負(fù)荷··············································

12、83;········42. 平均傳熱溫差········································

13、;·················43. 傳熱面積估算·······························&

14、#183;·························4五 工程結(jié)構(gòu)尺寸······················

15、3;······································51. 管徑和管內(nèi)流速··········

16、;··············································52. 管程數(shù)和傳熱管數(shù)··

17、;··················································

18、;··53. 平均傳熱溫差校正和殼程數(shù)·············································&

19、#183;54. 傳熱管排列和分程方法···············································

20、;···55. 殼程內(nèi)徑·············································

21、83;················66. 折流板································&#

22、183;·······························67. 其他附件·················

23、·············································68. 接管····

24、··················································

25、············6六換熱器核算·····································

26、;····························7 1.熱流量核算····················&#

27、183;··········································7 （1）殼程表面?zhèn)鳠嵯禂?shù)·····&

28、#183;·············································7 （2）管程表面?zhèn)鳠嵯禂?shù)··

29、·················································7 （3）污

30、垢熱阻和管壁熱阻················································

31、3;8 （4）傳熱系數(shù)K················································

32、·········8 （5）傳熱面積裕度·······································&

33、#183;···············8 2.壁溫核算·································

34、;································93.換熱器內(nèi)流體的流動(dòng)阻力···············

35、83;···································9 （1）管程流動(dòng)阻力············

36、3;···········································9 （2）殼程流動(dòng)阻力·····

37、;··················································

38、;10七換熱器主要工藝結(jié)構(gòu)尺寸和計(jì)算結(jié)果表·······································11八設(shè)備參考數(shù)計(jì)算······

39、;··················································

40、;···121.殼體壁厚·············································

41、83;·················12 2.接管法蘭·······························

42、································123.設(shè)備法蘭················

43、3;··············································12 4.封頭管箱··&

44、#183;·················································&

45、#183;··········12 5.設(shè)備法蘭墊片（橡膠石棉板）····································&

46、#183;·········126.管法蘭用墊片······································

47、83;····················137.管板····························

48、83;·······································138.支墊（鞍式支座）········

49、83;·················································139

50、.設(shè)備參數(shù)總表·················································

51、;··········13九設(shè)計(jì)總結(jié)······································

52、3;··························15十.主要符號(hào)說明 ······················

53、;······································16十一.參考文獻(xiàn)··········&#

54、183;·················································&#

55、183;···17一、設(shè)計(jì)說明書1.設(shè)計(jì)任務(wù)書和設(shè)計(jì)條件 原油44000kg/h由70°C被加熱到110°C與柴油換熱，柴油流量34000kg/h，柴油入口溫度175°C，出口溫度127。已知兩則污垢熱阻為0.0002·C/W,管程與殼程兩則降壓小于或等于0.3at，熱阻損失5%，初設(shè)k=250w/ m2·°C。二、設(shè)計(jì)條件及主要物性參數(shù)2.1設(shè)計(jì)條件由設(shè)計(jì)任務(wù)書可得設(shè)計(jì)條件如下表：數(shù)參類型體積流量（標(biāo)準(zhǔn)kg/h）進(jìn)口溫度（）出口溫度（）操作壓力（Mpa）設(shè)計(jì)壓力（Mpa）柴 油（管內(nèi)）34000175

56、1271.11.2原油（管外）4400070110 0.30.4注：要求設(shè)計(jì)的冷卻器在規(guī)定壓力下操作安全，必須使設(shè)計(jì)壓力比最大操作壓力略大，本設(shè)計(jì)的設(shè)計(jì)壓力比最大操作壓力大0.1MPa。2.2確定主要物性數(shù)據(jù)2.2.1定性溫度的確定根據(jù)流體力學(xué)（上）P177，公式（4-109），熱流量為 Qc = Wc Cpc(T1T2) ×1.05 =44000×2.2×（14842）×1.05=1.13×106kJ/h = 1.13×106 W 管程柴油的定性溫度為 殼程原油的定性溫度為 2.2.2流體有關(guān)物性數(shù)據(jù)根據(jù)由上面兩個(gè)定性溫度數(shù)據(jù)，查閱

57、參考書可得原油和柴油的物理性質(zhì)。運(yùn)用內(nèi)插法（公式為 ）,可得殼程和管程流體的有關(guān)物性數(shù)據(jù)。原油在90，1.2MPa下的有關(guān)物性數(shù)據(jù)如下：物性密度i（kg/m3）定壓比熱容cpi kJ/(kg)粘度i（Pa·s）導(dǎo)熱系數(shù)i（W·m-1·-1）原油 8152.26.65×10-3 0.128 柴油在151的物性數(shù)據(jù)如下：物性密度o（kg/m3）定壓比熱容cpo kJ/(kg)粘度o（Pa·s）導(dǎo)熱系數(shù)o（W·m-1·-1）柴油715 2.480.64×10-30.133三、確定設(shè)計(jì)方案3.1 選擇換熱器的類型由于溫差較

58、大和要便于清洗殼程污垢，對于油品換熱器，以采用Fe系列的浮頭式列管換熱器為宜。采用折流擋板，可使作為被冷卻的原油易形成湍流，可以提高對流表面?zhèn)鳠嵯禂?shù)，提高傳熱效率。3.2 流程安排柴油溫度高，走管程課減少熱損失，原油黏度較大，走殼程在較低的Re數(shù)時(shí)即可達(dá)到湍流，有利于提高其傳熱膜系數(shù)。四、估算傳熱面積4.1熱流量4.2平均傳熱溫差= (0,1atm)=614.3傳熱面積由于管程氣體壓力較高，故可選較大的總傳熱系數(shù)。初步設(shè)定設(shè)Ki=250 W·m-2·-1。根據(jù)化工單元過程及設(shè)備課程設(shè)計(jì)P44，公式3-8，則估算的傳熱面積為 m2五工程結(jié)構(gòu)尺寸5.1管徑和管內(nèi)流速選用25&#

59、215;2.5mm的傳熱管(碳鋼管)；由傳熱傳質(zhì)過程設(shè)備設(shè)計(jì)P7表13得管殼式換熱器中常用的流速范圍的數(shù)據(jù)，可設(shè)空氣流速ui1m/s，用u i計(jì)算傳熱膜系數(shù)，然后進(jìn)行校核。5.2管程數(shù)和傳熱管數(shù)依化工單元過程及設(shè)備課程設(shè)計(jì)P46，公式3-9可依據(jù)傳熱管內(nèi)徑和流速確定單程傳熱管數(shù)(根)按單程管計(jì)算，所需的傳熱管長度為m按單管程設(shè)計(jì)，傳熱管過長，宜采用多管程結(jié)構(gòu)?，F(xiàn)取傳熱管長 l= 7 m ，則該換熱器管程數(shù)為Np=L / l=22.5/74（管程）傳熱管總根數(shù) N = 42×4= 168 （根）。5.3 平均傳熱溫差校正及殼程數(shù)依化工單元過程及設(shè)備課程設(shè)計(jì)P46，公式3-13a和3-1

60、3b，平均傳熱溫差校正系數(shù)R1.2P0.381 依傳熱傳質(zhì)過程設(shè)備設(shè)計(jì)P16，公式3-13，溫度校正系數(shù)為 0.92依傳熱傳質(zhì)過程設(shè)備設(shè)計(jì)P16，公式3-14，平均傳熱差校正為tm=×tm =61×0.92=56.12( )由于平均傳熱溫差校正系數(shù)大于0.8，同時(shí)殼程流體流量較大，故取單殼程合適。5.4 傳熱管的排列和分程方法采用組合排列法，即每程內(nèi)均按旋轉(zhuǎn)45°正四邊形排列，其優(yōu)點(diǎn)為管板強(qiáng)度高，流體走短路的機(jī)會(huì)少，且管外流體擾動(dòng)較大，因而對流傳熱系數(shù)較高，相同的殼程內(nèi)可排列更多的管子。查化工單元過程及設(shè)備課程設(shè)計(jì)P50，表3-7 管間距，取管間距：t 1.25d

61、=1.25x25=32 mm 。由化工單元過程及設(shè)備課程設(shè)計(jì)P50，公式3-16，隔板中心到離其最近一排管中心距離S=t/2+6=32/2+6=22 mm取各程相鄰管的管心距為44mm。5.5 殼體內(nèi)徑 采用多管程結(jié)構(gòu)，取管板利用率=0.7，由化工單元過程及設(shè)備課程設(shè)計(jì)P51，公式3-20，得殼體內(nèi)徑為Di =1.05t=1.05×32×=520 mm , 圓整后取Di =600mm。5.6折流板采用弓形折流板，取弓形折流板圓缺高度為殼體內(nèi)徑的25%，則切去的圓缺高度為h=0.25×600=150 mm ，故可取h=150 mm。取折流板間距B=0.3Di，則B=

62、0.3×600=180 mm。折流板數(shù) NB=1=138 塊折流板圓缺面水平裝配。5.7其他附件直徑為12mm的拉桿4根。5.8接管（1）殼程流體進(jìn)出口接管 取接管內(nèi)液體流速u1=0.5m/s, =0.195(m)圓整后取管內(nèi)直徑為200mm.(2) 管程流體進(jìn)出口接管 取接管內(nèi)液體流速u2=1m/s,圓整后取管內(nèi)直徑為150mm六換熱器核算6.1熱量核算6.1.1殼程表面流傳熱系數(shù) 對于圓缺形折流板，可采用克恩公式。由化工單元過程及設(shè)備課程設(shè)計(jì)P53，公式3-22，得ho = 其中： 粘度校正為=1.05當(dāng)量直徑，管子為四邊形角形排列時(shí)，依化工單元過程及設(shè)備課程設(shè)計(jì)P53，公式3-

63、23a得de0.027 m殼程流通截面積，由化工單元過程及設(shè)備課程設(shè)計(jì)P54，公式3-25，得So = BD(1)=0.18×0.6×（1）0.023625 m2殼程冷卻水的流速及其雷諾數(shù)分別為uo =0.635 m/sReo1556普朗特準(zhǔn)數(shù)（<傳熱傳質(zhì)過程設(shè)備設(shè)計(jì)>P26，公式1-43）Pr =114.29因此，殼程水的傳熱膜系數(shù)ho為ho = =668 W/(m2·)6.1.2管程表面流傳熱系數(shù)由化工單元過程及設(shè)備課程設(shè)計(jì)P55，公式3-22，3-33,得hi = 0.023Re0.8Pr0.3其中：管程流通截面積Si =0.02637 m2管程

64、空氣的流速及其雷諾數(shù)分別為ui =0.5 m/sRe11172>10000普蘭特準(zhǔn)數(shù)Pr =11.93因此，管程空氣的傳熱膜系數(shù)hi為hi=0.023×111720.8×11.930.3×=557.3W/(m2·)6.1.3污垢熱阻和管壁熱阻l 冷卻水側(cè)的熱阻Rso0.0002m2··W-1l 熱空氣側(cè)的熱阻Rsi0.0002m2··W-1l 碳鋼的導(dǎo)熱系數(shù)50W·m-1·-16.1.4總傳熱系數(shù)Ki因此，依化工單元過程及設(shè)備課程設(shè)計(jì)P53，公式3-21 Rso 0.0002解得：236

65、W/ (m2·) 6.1.5 傳熱面積裕度依化工單元過程及設(shè)備課程設(shè)計(jì)P56，公式3-35：QiSitm得：SiQi/(tm)78.49 m2該換熱器的實(shí)際傳熱面積SpSp=3.14×0.05×7×168=92.316 m2依化工單元過程及設(shè)備課程設(shè)計(jì)P56，公式3-36該換熱器的面積裕度為=17.6%6.2 壁溫核算 因管壁很薄，且管壁熱阻很小，故管壁溫度可按化工單元過程及設(shè)備課程設(shè)計(jì)P77，公式3-42計(jì)算。由于傳熱管內(nèi)側(cè)污垢熱阻較大，會(huì)使傳熱管壁溫升高，降低了殼體和傳熱管壁溫之差。但在操作早期，污垢熱阻較小，殼體和傳熱管間壁溫差可能較大。計(jì)算中，應(yīng)

66、按最不利的操作條件考慮。因此，取兩側(cè)污垢熱阻為零計(jì)算傳熱管壁溫。于是按式3-42有式中，冷流體的平均溫度tm和熱流體的平均溫度Tm分別按化工單元過程及設(shè)備課程設(shè)計(jì)P77，公式3-44、3-45計(jì)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·)傳熱管平均壁溫=113.6 殼體壁溫，可近似取為殼程流體的平均溫度，即T=90 殼體壁溫和傳熱管壁溫之差為 t=113.690 =23.6 該溫差不大，不需要建立溫度補(bǔ)償

67、裝置。6.3換熱器內(nèi)流體的流動(dòng)阻力(壓降)6.3.1管程流動(dòng)阻力由，傳熱管相對粗超度為0.01，查莫狄圖得，流速u=0.05m/s, (pa)(pa)總壓降：pi（p1+p2）Ft Ns Np（1188.68+268.125）×1.5×1×48740Pa < 9800 Pa（符合設(shè)計(jì)要求） 其中， Ft為結(jié)垢校正系數(shù)，取1.5；Ns為串聯(lián)殼程數(shù)，取1；Np為管程數(shù)，取4。 6.3.2殼程流動(dòng)阻力：由化工單元過程及設(shè)備課程設(shè)計(jì)P58，公式3-51,3-52，得： 流體橫過管束的壓降：其中：F=0.4fo=5.0×1556-0.228=0.9358NB

68、=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總壓降：po（p1p2）Fs Ns（36989+18107）×1.15×163360.4Pa 其中，F(xiàn)s為殼程壓強(qiáng)降的校正系數(shù)，對于液體取1.15；Ns為串聯(lián)的殼程數(shù)，取1。七.換熱器主要結(jié)構(gòu)尺寸和計(jì)算結(jié)果表參數(shù)管程殼程流量，kg/h3400044000物性操作溫度，175/12770/11

69、0定性溫度，15190流體密度，kg/m3715815定壓比熱容，kj/(kg.k)2.482.2黏度，pa.s傳熱系數(shù)，W/（m2·）0.1330.128普朗特?cái)?shù)11.93114.2設(shè)備結(jié)構(gòu)參數(shù)形式浮頭式臺(tái)數(shù)1殼體內(nèi)徑，mm600殼程數(shù)1管徑，mm管心距，mm32管長，mm7000管子排列正方形旋轉(zhuǎn)45°管數(shù)目，根168折流板數(shù)38傳熱面積，92.316折流板間距，mm180管程數(shù)4材質(zhì)碳鋼主要計(jì)算結(jié)果管程殼程流速，m/s0.50.634表面?zhèn)鳠嵯禂?shù)，W/（m2·）668557.3污垢系數(shù)，m2·K/W0.00020.0002阻力降，Pa0.00870