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An annual production capacity of 10000 tons of toluene-the
distillation process design analyses
ABSTRAC
This design task is to design for the separation of benzene toluene-ethylbenzene float valve of the column. Distillation is a multi-stage separation process, that is also part of many times and part of the process of vaporization condensation. Distillation column, raw materials including device preheater, distillation kettle (reboiler), condenser, kettle liquid cooler and cooler equipment products. Heat from the tower kettle input, and the material in the tower of classics for many times condensation distillation separation, the condenser and cooler by the cooling medium will waste heat away.
According to the heating way to decide whether the bottom and set reboiler, bottom set reboiler is the indirect heating, the heating methods applicable to all kinds of things is, and has been widely used. Because this design set the reboiler, so by indirect heating. Because the benzene-toluene is easy to separate two components of things, so the atmospheric distillation. Feeding hot conditions choice bubble point feeding, so the tower in rectifying section and ask for the rise of the fractions steam content in equal, and don't get season the influence of climate.
Float valve tower in blister tower is developed on the basis of. It has a handling capacity, operating flexibility, high efficiency tower board, pressure is small, use cycle is long, etc. Determine the reflux ratio have graphic method and driven plate calculation method, this design USES the driven plate calculation method, although the calculation process more complicated, but the calculation precision.
Theory board is determined, the actual number of board, then design tower and the tower of the plate all the parameters, primaries tower and calculate the distance between plate tower diameter, these data are based on the calculation of rectifying section of data is based on. Float valve opening rate of the tower in the design to meet the requirements of the certain, that is, to determine the right number of float valve, float valves diameter is selected by the float valve model certain, float valve number rise through the hole, steam content in gas velocity and aperture sure, this is just a calculation theory float valve number, the actual will be determined by tower board layout, if the number is not float valve arrangement in
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conjunction hole rate and the hole gas velocity, will decorate afresh to meet the requirements, the hole by the arrangement of an isosceles triangle fork row.
The last is tower plate load performance figure smuggled with foam fog in line, the liquid limit line, the liquid leakage line, the lower the calculation of liquid phase load line and make sure tower body structure.
Keywords: distillation column, float valve, into the bubble point
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目 录
摘 要 .................................................................... V ABSTRAC ................................................................. VI 1 绪论 ................................................................. 1 1.1 设计背景 ........................................................... 1 1.2 甲苯的性质及用途 .................................................... 1 1.2.1甲苯的物理性质 .................................................. 1 1.2.2甲苯的化学性质 .................................................. 1 1.2.3甲苯的用途 ...................................................... 2 1.3．苯的国内外现状..................................................... 2 1.3.1.国内现状 ........................................................ 2 1.3.2国外情况 ........................................................ 3 1.4．精馏原理........................................................... 4 1.5．主要设备........................................................... 4 1.5.1.浮阀塔 .......................................................... 5 1.5.2再沸器 .......................................................... 5 1.5.3冷凝器 .......................................................... 5 1.6.操作条件............................................................ 5 1.6.1操作条件的确定 .................................................. 5 1.6.2 操作压力 ........................................................ 6 1.6.3 加料方式. ....................................................... 6 1.6.4 进料状态. ....................................................... 6 1.6.5 冷凝方式. ....................................................... 6 1.6.6 加热方式. ....................................................... 7 1.6.7 热能的利用 ...................................................... 7 1.6.8确定设计方案的原则 .............................................. 7 1.7．目前的生产方法..................................................... 8 1.8．流程说明........................................................... 8 1.9．问题研究........................................................... 8
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2 工艺计算 ............................................................ 10 2.2 塔的物料衡算 ....................................................... 10 2.2.1原料液及塔顶、塔底产品的摩尔分数。 ............................. 10 2.2.2原料液及塔顶、塔底产品的平均摩尔质量 ........................... 10 2.3 塔板数的确定 ....................................................... 11 2.3.1理论板层数NT的求取 ............................................. 11 2.3.2相平衡线方程的确定 ............................................. 13 2.3.3实际板层数的求取 ............................................... 15 2．4热量衡算 .......................................................... 15 2.5 塔的工艺条件及有关物性数据的计算 ................................... 17 2.5.1操作压力的计算 ................................................. 17 2.5.2操作温度计算 ................................................... 17 2.5.3 平均摩尔质量计算 .............................................. 17 2.5.4平均密度计算 ................................................... 18 2.5.5液体平均表面张力的计算 ......................................... 19 2.5.6液体平均黏度计算 ............................................... 20 2.6塔体工艺尺寸计算 ................................................... 21 2.6.1精馏段的气、液相体积流率为 ..................................... 21 2.6.2精馏塔有效高度的计算 ........................................... 23 2.6.3塔高的计算 ..................................................... 24 2.7 塔板主要工艺尺寸的计算 ............................................. 24 2.7.1溢流装置的计算 ................................................. 24 2.7.2 塔板布置 ....................................................... 26 2.8 浮阀塔的流体力学验算 .............................................. 28 2.8.1 塔板压降 ....................................................... 28 2.8.2淹塔 ........................................................... 30 2.8.3雾沫夹带 ....................................................... 30 2.9塔板负荷性能图 ..................................................... 32 2.9.1雾沫夹带线 ..................................................... 32 2.9.2液泛线 ......................................................... 33 2.9.3液相负荷上限线 ................................................. 34
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2.9.4漏液线对于重阀（为不发生严重漏液现象时的最低气相负荷） ......... 34 2.9.5液相负荷下限线 ................................................. 35 2.9.6塔的操作弹性 ................................................... 35 3塔体结构 ............................................................... 37 3.1塔顶空间 ........................................................... 37 3.2人孔 ............................................................... 37 3.3塔高 ............................................................... 37 4 辅助设备 ........................................................... 38 4.1 管道规格 ........................................................... 38 4.1.1 原料管: ........................................................ 38 4.1.2 塔出料管： ..................................................... 38 4.1.3塔顶回流管 ..................................................... 38 4.1.4 塔釜出料管 .................................................... 38 4.2 储槽（原料罐） ..................................................... 39 4.3 选泵（进料泵） .................................................... 39 4.4 所设计浮阀塔的主要结果总汇表 ....................................... 41 5 结论与讨论 ............................................................ 43 5.1结论 ............................................................... 43 5.2方案讨论 ........................................................... 43 5.2.1 关于节能型方案的选择 ........................................... 43 5.2.2 关于操作条件优化节能 ........................................... 43 5.2.3 关于强制回流的讨论 ............................................. 43 5.2.4 关于负荷性图的讨论 ............................................ 43 5.2.5 关于换热器的选择 .............................................. 44 参 考 文 献 ............................................................. 45 致 谢 ................................................................... 46 符号说明 ................................................................ 47 附 录 ................................................................... 49