化工原理课程设计精馏塔

1、南 京 工 业 大 学化 工 原 理 课 程 设 计 任 务 书专业： 生物工程 班级： 0503 姓名： 茆敏 设计日期： 2008 年 6 月 30 日至 2008 年 7 月 11 日设计题目： 甲醇精馏塔 设计条件： 进 料 量：F = 65 吨/天 进料组成：Xf = 45 % (w%) 进料状态：25塔顶产品：XD 96%(w%) 回 收 率: 98%塔顶压力：常压 指导教师：祝宁东，陈晓蓉 2008年 6 月 24 日 目 录一 前 言············&

2、#183;·················································&

3、#183;·····································4二 设计题目···········

4、··················································

5、··················································

6、··········5三 设计说明书符号表······································&

7、#183;·················································&

8、#183;················5四 工艺流程原理与流程图·······························

9、··················································

10、··········6五 物性参数·······································

11、;··················································

12、;································7六 工艺计算················

13、3;·················································

14、3;·················································

15、3;····86.1 汽液平衡数据和汽液平衡（T-x-y）图·········································

16、3;·····················86.2 物料衡算···························&

17、#183;·················································&

18、#183;···································96.2.1 数据换算············&#

19、183;·················································&#

20、183;··········································9 物料衡算······&#

21、183;·················································&#

22、183;················································96.3理论板数

23、计算·················································

24、3;·················································

25、3;······96.3.1 板数和回流比的关系·········································

26、··········································96.3.2理论板数图解······

27、··················································

28、········································106.3.3 严格法计算模拟过程·······&

29、#183;·················································&

30、#183;·························11七 塔和塔板主要工艺尺寸计算·····················

31、83;·················································

32、83;···············117.1塔内物性计算································

33、3;·················································

34、3;·······················11平均分子量的计算·························

35、··················································

36、·················117.1.2 液相平均密度······························

37、3;·················································

38、3;··················117.1.3 汽相平均密度·····························&#

39、183;·················································&#

40、183;···················127.2 塔径与塔高计算····························&

41、#183;·················································&

42、#183;······················127.2.1 精馏段塔径·························

43、··················································

44、····························127.2.2 提馏段塔径····················

45、;··················································

46、;·································137.2.3 圆整后塔径··············

47、3;·················································

48、3;······································137.3填料层高度计算·········

49、3;·················································

50、3;···································137.4 填料塔的流体力学性能············

51、··················································

52、···························137.4.1 压降·····················&#

53、183;·················································&#

54、183;···········································137.4.2 泛点气速····&#

55、183;·················································&#

56、183;·················································&#

57、183;··147.4.3 精馏段·············································

58、83;·················································

59、83;···············147.4.4 提馏段································

60、3;·················································

61、3;····························14 7.5 塔内附件选择···················

62、83;·················································

63、83;··············14 液体喷淋装置选择·································

64、3;·················································

65、3;·······14液体再分布装置选择·········································

66、;···········································15 填料支撑装置选择·····

67、··················································

68、·····························15 7.5.4 除沫器选择··················

69、3;·················································

70、3;···············167.6 管道设计与选择································

71、83;·················································

72、83;··················167.6.1塔顶回流管管径·····························&

73、#183;·················································&

74、#183;··············167.6.2 进料管管径·································

75、··················································

76、··················17 塔顶蒸汽出口管······························&#

77、183;·················································&#

78、183;············177.6.4 塔顶产品出口管···································

79、;··················································

80、;········177.6.5 塔釜出料管管径·······································&#

81、183;·················································&#

82、183;···187.6.6 塔釜回流管管径············································

83、;·················································187.7

84、 其他部件·················································&

85、#183;·················································&

86、#183;·············187.7.1 筒体··································

87、83;·················································

88、83;······························187.7.2 封头··················

89、;··················································

90、;···············································197.7.3 法兰·&

91、#183;·················································&

92、#183;·················································&

93、#183;·············207.7.4 裙座··································

94、83;·················································

95、83;······························20塔总高度计算··················&

96、#183;·················································&

97、#183;·······························20八 塔设计计算参数总汇················

98、··················································

99、·································21九 辅助设备···············

100、3;·················································

101、3;·················································

102、3;···219.1 辅助设备及零部件的选择············································

103、;·········································21 塔顶冷凝器的选择·······

104、··················································

105、································21 塔底再沸器的选择················&

106、#183;·················································&

107、#183;······················22 塔底预热器的选择·························&#

108、183;·················································&#

109、183;·············22 进料泵···································&#

110、183;·················································&#

111、183;·························23 回流泵·······················&#

112、183;·················································&#

113、183;·····································23十 参考文献···········

114、··················································

115、··················································

116、········23一 前 言工业甲醇的用途十分广泛，除可作许多有机物的良好溶剂外，主要用于合成纤维、甲醛、塑料、医药、农药、染料、合成蛋白质等工业生产，是一种基本的有机化工原料。甲醇和汽油（柴油）或其它物质可混合成各种不同用途的工业用或民用的新型燃料，甲醇和汽油混合可作为燃料用于运输业。塔设备是化工，制药，环保等生产中广泛应用的气液传质设备。根据塔内气液接触部件的形式，可以分为填料塔和板式塔。板式塔属于逐级接触逆流操作，填料塔属于微分接触操作。工业上对塔设备的主要要求：（1）生产能力大（2）分离效率高（3）操作弹

117、性大（4）气体阻力小结构简单、设备取材面广等。塔型的合理选择是做好塔设备设计的首要环节，选择时应考虑物料的性质、操作的条件、塔设备的性能以及塔设备的制造、安装、运转和维修等方面的因素。板式塔的研究起步较早，其流体力学和传质模型比较成熟，数据可靠。尽管与填料塔相比效率较低、通量较小、压降较高、持液量较大，但由于结构简单、造价较低、适应性强、易于放大等特点，因而在70年代以前的很长一段时间内，塔板的研究一直处于领先地位。然而，70年代初期出现的世界能源危机迫使填料塔技术在近20年来取得了长足进展。由于性能优良的新填料相继问世，特别是规整填料和新型塔内件的不断开发应用和基础理论研究的不断深入，使填料

118、的放大技术有了新的突破，改变了以板式塔为主的局面。在我国，随着石油化工的不断发展，传质分离工程学的研究不断深入，使填料塔技术及其应用进入了一个崭新的时期，其工业应用与发达国家并驾齐驱，进入世界先进行列。填料塔在塔径较小（D0.6）时应用更为普遍。填料塔由填料、塔内件及筒体构成。填料分规整填料和散装填料两大类。塔内件有不同形式的液体分布装置、填料固定装置或填料压紧装置、填料支承装置、液体收集再分布装置及气体分布装置等。与板式塔相比，新型的填料塔性能具有如下特点：生产能力大、分离效率高、压力降小、操作弹性大、持液量小等优点。本设计是甲醇精馏,由于需要回收率达到98%,塔顶产品浓度96%,选用了分离

119、效率高，压降低的填料塔.二、设计题目甲醇精馏塔65吨/天45%（含醇w%）其余为水进料25°C回收率98 % 塔顶产品浓度96%三、设计说明书符号表表3-1 设计说明符号表符号名称单位F进料流量kmol/hD塔顶产品流量kmol/hW塔底产品流量kmol/hM摩尔质量kg/kmolN理论塔板数R回流比P压强Pat温度气体粘度Pa·sV气相摩尔流量kmol/hW液相摩尔流量kmol/hXD塔顶产品浓度XW塔底产品浓度x液相摩尔分数y气相摩尔分数组分的相对挥发度回收率密度kg/m3u气速m/sa填料比表面积l/mg重力加速度m/s2空隙率Z高度mLh喷淋量m3/hU喷淋密度m3

120、/m2hr汽化潜热kj/kgK传热系数W/ m2c比热kj/kgA面积m2H扬程m四、工艺流程原理与流程图进料泵将物料送至填料精馏塔进行精馏操作，塔顶上升蒸汽采用全凝器冷凝后，一部分进行回流，另一部分作为塔顶产品冷凝后送至储槽，塔釜采用间接蒸汽加热。五、物性参数水的物性参数: 分子量18压强/Pa温度t/密度比热容黏度汽化热H/(kJ/kg)1.010999.94.212178.78-10999.74.191130.5327020998.24.183100.4234830995.74.17480.1239840992.24.17465.3245050988.14.17454.934886098

121、3.24.17846.9853070977.84.16740.6055580971.84.19535.5068090965.34.20831.48625100958.44.22028.24640甲醇的物性参数: 分子量 32压强/Pa温度t/密度比热容黏度汽化热H/(kJ/kg)1.0108092.3660.825-108012.4580.700170207922.5120.600205307822.5500.524242407722.5720.470270507642.6180.400289607542.6750.510310707462.7300.319325807362.7700.278

122、344907252.8310.2453601007142.8920.225372六、工艺计算6.1 汽液平衡数据和汽液平衡（T-x-y）图表6-1 汽液平衡数据表压强/kPa温度/甲醇摩尔分数/%挥发度液相中x汽相中y101.32592.90.05310.28347.0523390.30.07670.40018.02855188.90.09260.43537.55368186.60.12570.5057.095964850.13150.54557.92692883.20.16740.55856.29177882.30.18180.57756.15163981.60.20830.62736.39

123、716180.20.23190.64856.110851780.28180.67755.35406977.80.29090.68015.18229776.70.33330.69184.48996676.20.35130.73475.11373973.80.4620.77564.02490172.70.52920.79713.49500271.30.59370.81833.082034700.68490.84922.590776680.77010.89622.57750566.90.87410.91941.642987 图6-1 甲醇水的t-x-y图6.2、物料衡算6.2.1 数据换算质量分数换

124、算到摩尔分数 : 单位换算: 物料衡算F=D+W FXF=DXD+WXW DXD/FXF=得：D= 40.085 Kmol/hW=80.175Kmol/hXW= 0.016.3理论板数计算6.3.1 适宜回流比确定一般R加大,理论板数较少,塔设备投资少,但气化量大,能耗高,操作费用少。R减少,理论板数较多,塔设备投资大，但气化量小，能耗高，操作费用多。由XD 、XW、R可确定N，取RN作图如下： 此图为坐标纸手画图 图6-3-1 NR关系图6.3.2 理论板数图解进料温度是25,使用预热器加热到泡点进料：q=1q线方程: 由气液平衡数据描点画图,如下图00.10.20.30.40.50.60.

125、70.80.9100.10.20.30.40.50.60.70.80.916.3.3 严格法计算模拟过程由图得回流比 R=1精馏段操作线方程: 提馏段操作线方程: 精馏段理论板数 = 5 进料板:第6块提馏段理论板数 = 3.92 (包括再沸器)总理论板数 N = 8.92 (包括再沸器)6.3.3 用ASPEN PLUS 软件验算以上节计算为基础，采用ASPEN PLUS模拟软件的严格法计算模型， 验算得精馏塔的操作参数如下表表6-3-3精馏塔模拟计算结果总理论板数：9加料位置：6塔顶：全凝器塔釜：再沸器DFWB1B1B1LIQUIDLIQUIDLIQUIDSubstream: MIXED

126、Mole Flow kmol/hr METHA-01 37.2827538.035911.003159 WATER 3.05224882.6846279.63238Total Flow kmol/hr 40.085120.720580.63553Total Flow kg/hr 1241.5962708.3391466.743Total Flow l/min 27.47754.4538926.74591Temperature K 338.8564350.8648370.9055Pressure atm 111模拟结果表明：七、塔和塔主板主要工艺尺寸计算7.1物性计算精馏段按第 块处温度和组成确

127、定物性，提留段按第 块处温度和组成确定物性平均分子量的计算塔顶的平均分子量进料板的平均分子量塔底的平均分子量精馏段,提馏段的平均分子量 精馏段平均分子量 提馏段平均分子量 7.1.2 液相平均密度查物性数据1：（甲醇）密度1 720 kg/m3 （水）密度2 970 kg/ m3塔顶（甲醇）质量百分比a1 96%（将X1换算成质量分率）进料（甲醇）质量百分比a2 45%（将Xn换算成质量分率）塔底（甲醇）质量百分比a3 1.8%（将Xw换算成质量分率）塔顶液相密度：LD1/a1/1+(1-a1) /2= 727.50 kg/ m3 进料液相密度：LF1/a2/1+(1-a2) /2= 838.

128、92 kg/ m3 塔底液相密度：LW1/a3/1+(1-a3) /2=963.98 kg/ m3 精馏段的平均液相密度：LM(LD+LF)/2= 783.21 kg/ m3提馏段的平均液相密度：LM(LF+LW)/2=901.45 kg/ m3 7.1.3 汽相平均密度根据塔顶组成查水-甲醇平衡体系t-x-y图1，得塔顶温度TD=67根据进料板组成查水-甲醇平衡体系t-x-y图1，得进料板温度TF=77根据塔底组成查水-甲醇平衡体系t-x-y图1，得塔底温度TW=98精馏段：TM=（TF+TD）/2= 72 VMPMV/RTM= 1.02 Kg/ m3提馏段：TM=（TF+TW）/2= 87

129、.5VMPMV/RTM= 0.77 Kg/ m37.2 塔径与塔高计算7.2.1精馏段塔径 最近规整填料得到较快，使用规整填料塔性能稳定，气液体再分布性能均匀，塔的分离效能高，压力降低，能适应较高的气速和较低的回流比，弹性大。表7-2-1规整填料性能填料类型理论板数N,1/m比表面积at，1/m空隙率P/Z,Mpa/mAK125X塑料孔板波纹填料0.8512598.51.4*1040.2911.563lg(L,D)= XD×lg(L,轻组分)+（1XD）×lg(L,重组分)lg(L,F)= Xn×lg(L,轻组分)+（1Xn）×lg(L,重组分) （Xn

130、：加料板上的液相组成）液体粘度L(L,D+L,F/2） mPas计算：液相质量流量WL=L=RD= 1244.1 kg/h (L换算成质量流量)气相质量流量WG=V=(R+1)D= 2388.6 kg/h (V换算成质量流量)带入数据得:计算得泛点气速uf= 5.80 m/s一般取u0.8uf· 计算泛点气速uf= 5.80 m/s u 4.64 m/s D= 0.423 m提馏段塔径lg(L,F)= Xn×lg(L,轻组分)+（1Xn）×lg(L,重组分) （Xn：加料板上的液相摩尔分率）lg(L,W)= XW×lg(L,轻组分)+（1XW）×

131、;lg(L,重组分)液体粘度L(L,W+L,F/2） mPas计算：液相质量流量WL=L=(L+qF)= 3952.4 kg/h (L换算成质量流量)气相质量流量WG=V=V-(1-q)F= 2388.6 kg/h (V换算成质量流量) 计算得泛点气速uf= 5.97 m/s一般取u0.8uf· u 4.78 m/s D= 0.480 m7.2.3圆整后塔径精馏段塔径园整后D= 0.4 m 提馏段塔径园整后D= 0.4 m 7.3填料层高度计算精馏段的高度Z1N精馏段/ N 5.88 m圆整到6m,分两层,每层3m提馏段的高度Z2N提馏段/ N 3.44 m （N提馏段包括加料板）

132、圆整到3.5m,一层总填料层高度 Z=9.5 mN：见上表 7.4 填料塔的流体力学性能压降精馏段PZ精馏段×P/Z Pa提馏段P Z提馏段×P/Z Pa（N提馏段包括加料板）P/Z见上表7.4.2泛点气速精馏段u= 5.02 m/s （前已经算出） 泛点率=u/uf=0.8 提馏段u= 5.20 m/s （前已经算出） 泛点率=u/ uf=0.87.4.3精馏段液体喷淋量Lh 1.59 m3/h（将L换成m3/h，LhWL /LM）喷淋密度：U=Lh/0.785D2= 12.65 m3/m2h最小喷淋密度：Umin=(Lw)min= 15 m3/m2h式中：填料的比表面积，m2/m3；Umin最小喷淋密度，m3/（m2·h）；(Lw)min最小润湿率，m3/（m·h）。 (Lw)min的取值如下：因此： (L