目录一、设计题目_________________ 1二、设计依据_________________ 1三、设计要求_________________ 1第1节：物料衡算、热量衡算 ____________________________________________ 11.精馏塔物料衡算 ______________________________________________________________ 12.冷凝器物料衡算及热量衡算 ___________________________________________________ 103.产品冷却器物料衡算及热量衡算 _______________________________________________ 124.原料预热器（1）的物料衡算及热量衡算________________________________________ 135.原料预热器（2）的物料衡算及热量衡算________________________________________ 146.再沸器的物料衡算及热量衡算 _________________________________________________ 157.物料衡算汇总表 _____________________________________________________________ 168.热量衡算及换热器要求汇总表 _________________________________________________ 17第2节：列管式换热器选型及校核（原料预热器①）________________________ 181.初选原料预热器（1）规格 ____________________________________________________ 182.核算总传热系数 _____________________________________________________________ 25第3节：所选固定管板式换热器的结构说明_______________________________ 271.管程结构 ___________________________________________________________________ 272.壳体结构 ___________________________________________________________________ 283.其他主要附件 _______________________________________________________________ 29第4节：换热器的主要结构和计算结果___________________________________ 29第5节：参考文献及资料 _______________________________________________ 30附___________________________ 31设计任务书一、设计题目：乙醇水精馏系统换热器设计二、设计依据：1、产量：7万吨2、年工作时间：330天3、原料乙醇：浓度50%（质量），出库温度25℃4、产品乙醇：浓度95%（质量），入库温度≤45℃5、乙醇回收率：99.5%6、原料乙醇泡点进料，回流比R=1.15R min7、循环冷却水进口温度：30℃8、再沸器饱和水蒸气温度：150℃9、系统散热损失：不考虑系统散热损失10、换热器KA值裕度：20~40%11、原料预热器（2）设计三、设计要求：第1节：物料衡算、热量衡算1.精馏塔物料衡算乙醇、水的相对分子质量为M乙醇=46.07g/mol，M水=18.02g/mol 由原料乙醇质量浓度为50%得原料乙醇的摩尔分率为：F=50%/M X 50%/M M 50%/46.07=50%/46.07+50%/18.02=0.2812乙醇乙醇水+50%/ 由产品乙醇质量浓度为95%得产品乙醇的摩尔分率为：D 95%/X =95%/95%/46.0795%/46.075%/18.020.8814M M =+=乙醇乙醇水+5%/M 原料F 、塔顶馏出液D 的平均相对分子质量：F X M /F F M X g mol=⨯M +⨯⨯46.07+⨯18.02=25.91乙醇水（1-）=0.2812（1-0.2812） D D D X M 8814881442.74/M X g mol=⨯M +⨯⨯46.07+⨯18.02=乙醇水（1-）=0.（1-0.） 塔顶产品流率D ：(33024)D MD M h=⨯⨯()7371042.7433024206.79/8.83810/h kmol h kg h⨯=⨯⨯==⨯由乙醇回收率99.5%DFDX FX η==得：206.790.88140.28120.995651.42/D F DX F X kmol hη=⨯=⨯=4651.4225.9116878.29/1.68810/F kg hkg h =⨯=≈⨯流率W ：651.42206.79444.63/W F Dkmol h=-=-= 塔底残液摩尔分率：3651.420.2812206.790.8814444.632.0610F DW FX DX X W--=⨯-⨯==⨯塔底残液W 的平均相对分子质量：()()mol g M X M X M W W W /08.1802.181006.2-107.461006.213-3-=⨯⨯+⨯⨯=⨯-+⨯=水乙醇 3444.6318.088038.91/8.04010/W kg h kg h=⨯=≈⨯ 计算R min乙醇-水气液平衡数据P(kPa) T(℃) X Y101.325 100.01770 0101.325 94.808570.0204080.187889101.325 91.457910.0408160.295516101.325 89.131880.0612240.365032101.325 87.445820.0816330.413396101.325 86.174730.1020410.448925101.325 85.192160.1224490.476089101.325 84.415180.1428570.497555101.325 83.78810.1632650.515008101.325 83.272240.1836740.529566101.325 82.839990.2040820.542004101.325 82.471220.224490.552871101.325 82.151070.2448980.562574101.325 81.868420.2653060.571414101.325 81.614870.2857140.579625101.325 81.384050.3061220.587387101.325 81.171150.3265310.594843101.325 80.972470.3469390.602108101.325 80.785250.3673470.609275101.325 80.607390.3877550.616421101.325 80.437340.4081630.62361101.325 80.273950.4285710.630897101.325 80.116440.448980.638329101.325 79.964250.4693880.645945101.325 79.817050.4897960.653783101.325 79.674650.5102040.661873101.325 79.5370.5306120.670245101.325 79.404160.551020.678926101.325 79.276250.5714290.687942101.325 79.153470.5918370.697317101.325 79.036060.6122450.707074101.325 78.922230.6326530.7172735 8 1 8101.325 78.717420.6734690.738896101.325 78.624790.6938780.750411101.325 78.539170.7142860.762426101.325 78.460950.7346940.774966101.325 78.390520.7551020.788058101.32578.3283 0.77551 0.80173 101.325 78.27470.7959180.816009101.325 78.230130.8163270.830926101.325 78.195040.8367350.846514101.325 78.169870.8571430.8628075 5 1 1101.325 78.151050.8979590.897655101.325 78.158340.9183670.916291101.325 78.177390.9387760.935794101.325 78.20870.9591840.956211101.325 78.252760.9795920.977595101.325 78.310331 1作图如下：由图可得min 0.1931DX R =+，故R min =3.57R=1.15R min =1.15⨯3.57=4.1055塔顶冷凝器将来自塔顶的蒸汽全部冷凝，即该冷凝器为全凝器，凝液在泡点温度下部分地回流入塔，由恒摩尔流假定，塔顶液体摩尔流率L 、气体摩尔流率V 为:44.1055206.79848.898/3.62810/L RDkmol h kg h==⨯==⨯()415.1055206.791055.77/45123.45/4.51210/V R D kmol h kg h kg h=+=⨯==≈⨯ 因为是泡点进料，所以q=1()()()()()4V V 1114.10551206.7911651.421055.77/19088.32/ 1.90910/q F R D q Fkmol h kg h kg h =--=+--=+⨯--⨯==≈⨯344.1055206.791651.421.510/27127.17/2.71310/L L qFRD qFkmol h kg h kg h=+=+=⨯+⨯≈⨯=≈⨯ 又W=1.76*10-3，则V =L -W 成立 2.冷凝器物料衡算及热量衡算查【《化工原理》下册P268附录】得，质量组成为95%的乙醇水溶液的沸点为78.2℃。