化工原理课程设计
气相组成yD: yD??DxD1?(?D?1)xD yD?99.64%
进料温度: tF=86.59℃ 气相组成yF:yF??FxF1?(?F?1)xF yF?68.97%塔底组成: tW =97.99℃ 气相组成yW: yW?(1)精馏段
液相组成x1: x1?气相组成y1: y1?所以ML1?WxW1?(?W?1)xW yW?0.026%
xD?xF2yD?yF2 x1?99.23?)9.64?%1.63%?75.43 h.97%?84.31 % y1??46?0.7543?60?(1?0.7543)?49.4398 kg/kmol
MV1?46?0.8431?60?(1?0.8431)?48.1966 kg/kmol (2)提馏段
液相组成x2:x2?气相组成y2: y2?所以 MML2xW?xF2yW?yF2 x2? y2?0.013? .026?%1.63%?25.82 h.97%?34.50 %?46?0.2582?60?(1?0.2582)?56.385?46?0.3450?60?(1?0.3450)?55.17
kg/kmo l kg/kmo lV2表2.2 醇类密度表 温度T,℃ ?a,kg/m3 ?b,kg/m3 70 754.2 759.6 80 742.3 748.7 90 730.1 737.5 100 717.4 726.1 110 704.3 714.2 由不同温度下乙醇和丙醇的密度,内差法求tF tD tW下的乙醇和丙醇的密度
tF?86.59Co
90?80730.1?742.3?90?86.59730.1??cF ?cF?734.2 6 7
化工原理课程设计
90?80737.5?748.71?90?86.59737.5??wF ?wF?741.3 2
?F?0.45?10.45 ?F?738.1 3?734.26741.3280?97.17742.3??cD8?0tD?79.17Co
80?70742.3?754.2? ?cD?743.2 979.17
80?70748.?71?759.6?7?4w8.7D ?wD?749.60
?D?0.99743.2990?1?0.99749.601?00 ?D?743.3 597.99tW?97.99Co
100?717.?4100?726.?11?730.1?7?1cW7.41?00 ?cW?719.9 5
90?737.597.99?7?2w6.1W ?wW?728.3 9?W?0.0001719.95?1?0.0001728.39?740.74
?W?728.3 9所以?L1?
?L2??F??D2?738.13?743.352728.39?738.132?W??F2??733.26
?LD?xD?46?(1?xD)?60?LD?0.9923?46?(1?0.9923)?60?46.11kg/kmol?LF?xF?46?(1?xF)?60
?LF?0.5163?46?(1?0.5163)?60?52.77kg/kmol
?LW?xW?46?(1?xW)?60
?LW?0.00013?46?(1?0.00013)?60?60.00kg/kmol
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化工原理课程设计
?L1??LD??LF2?LW??LF2?46.11?52.77260.00?52.772?49.44kg/kmol
?L2???56.39kg/kmol
?VD?yD?46?(1?yD)?60
?VD?0.9964?46?(1?0.9964)?60?46.05kg/kmol
?VF?yF?46?(1?yF)?60
?VF?0.6897?46?(1?0.6897)?60?50.34kg/kmol
?VW?yW?46?(1?yW)?60
?VW?0.00026?46?(1?0.00026)?60?60.00kg/kmol
?V1??VD??VF2?VW??VF2?46.05?50.34260.00?50.342?48.20kg/kmol
?V2???55.17kg/kmol
?VF?50.34?273.15?104.3622.4?101.325?(273.15?86.59)46.05?273.15?104.3622.4?101.325?(273.15?79.17)60.00?273.15?104.3622.4?101.325?(273.15?97.99)1.757?1.64221.757?2.0302?1.70?1.757
?VD??1.642
?VW??2.030
?V1??V2?
?1.894
2.2.3 混合液体平均表面张力
根据内差法求的表面张力
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化工原理课程设计
表2.3 醇类液体表面张力 mN/m 温度,℃ 名称 60 80 100 乙醇 20.25 18.28 16.29 正丙醇 21.27 19.40 17.50 塔顶液相平均表面张力的计算:
tD?79.17Co
180?18.2?860?20.25?8079.17 ?DA?18.3 6mN/m?1?8DA.2879.17 ?DB?19.4 8mN/m?1?9D.B40
80?6019.4?0?21.278?0
?D??A?DA??B?DB?0.99?18.36?(1?0.99)?19.48?18.37mN/m
进料板液相平均表面张力的计算:
tW?97.99Co
100?16.2?9100?17.5?080?18.281?0097.99 ?WA?16.4 9 mN/m ?1?6W.A29
80?19.401?0097.99 ?WB?17.6 9 mN/m ?1?7W.B50?W??A?WA??B?WB?0.0001?16.49?(1?0.0001)?17.69?17.69mN/m
塔底液相平均表面张力的计算:
tF?86.59Co
100?16.2?9100?17.5?080?18.281?0086.59 ?FA?17.6 2mN/m?1?6FA.2986.59 ?FB?18.7 7mN/m?1?7FB.50
80?19.401?00
?F??A?FA??B?FB?0.45?17.62?(1?0.45)?18.77?18.25
?D??F2?F??W218.37?18.25217.69?18.252(1)精馏段的平均表面张力:?1???18.31
(2)提馏段的平均表面张力:?2?
??17.97
2.2.4 混合物的粘度
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化工原理课程设计
表2.4 醇类液体粘度 mPa.s 温度,℃ 名称 60 80 100 乙醇 0.601 0.495 0.361 正丙醇 0.899 0.619 0.444 根据内差法求不同温度下的粘度 B t1?82.88oC 查表,得?乙醇?0.476mpa·s, ?丙醇?0.594mpa·s t1?92.29oC 查表,得?乙醇?0.413mpa·s, ?丙醇?0.511mpa·s (1)精馏段粘度:
?1??乙醇x1??丙醇(1?x1)
?0.476?0.7543?0.594?(1?0.7543)?0.5046 mpa·s
(1)提留段粘度:
?2??'乙醇x2??'丙醇(1?x2)
?0.413?0.2582?0.511?(1?0.2582)?0.4857mpa·s
2.2.5 相对挥发度
(1)精馏段的平均相对挥发度: ?1?(2)提留段的平均相对挥发度: ?2??D??F22??2.131?2.082422.0211?2.08242?2.107 ?2.052?W??F
2.2.6 气液相体积流量计算
R?5
5 D?0.009 kmol/s
(1) 精馏段
L?RD?5?0.0095?0.0475 kmol/s V?(R?1)D?(5?1?)0.00?95 kmol/s 0 已知:ML1?49.44 kg/kmol MV1?48.20 kg/kmol
330kg/m kg/m ?V1?1.7 ?L1?740.7 4 质量流量:L1?ML1L?49.44?0.0475?2.348 kg/s V1?MV1V?48.20?0.057?2.747 kg/s
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