催化反应工程华东理工大学第五章2环氧乙烷合成反应器

1、二 环氧乙烷合成反应器 11 环氧乙烷反应体系特性 (1) (2) (3)在银催化剂上，乙烯（简称ET）氧化除得到产物环氧乙烷（简称EO）外，主要副产物是二氧化碳和水。反应（1）为选择氧化反应，反应（2）为深度氧化反应。选反应（1）和反应（2）为独立反应，C2H4和CO2为关键组分。2管壳型反应器32. 一维模型环氧乙烷反应器 反应器模型 物料衡算热量衡算4整理上式，得：床层的压力降初值条件5已知条件反应器内径 8.034m 反应管 453.5mm 高度 8m 管数 15431根入口压力 1.89MPa 入口温度 178 沸腾水压力 2.4252MPa 温度 223 反应器入口气量 81884

2、5Nm3/h反应器入口气体组成组 分C2H4O2EOCO2H2OCH4ArN2C2H6摩尔分率0.300.080.00010.050.0050.50860.05270.00140.00226计算结果体积/m3 140.0入口温度/ 178热点温度/ 231.9 出口温度/ 230.2yout /%C2H4 27.90 EO 1.97 CO2 5.91产量/t.d-1 750.2选择性/% 82.03P/MPa 0.18973. 二维模型环氧乙烷反应器气相方程8反应器模型二维非均相固相方程9反应器模型二维非均相边界条件其中，10将上述数学模型无因次化，无因次准数为反应器模型二维非均相11反应器模

3、型二维非均相气相方程（无因次化）12反应器模型二维非均相固相方程（无因次化）13反应器模型二维非均相边界条件（无因次化）14模型参数的计算公式 径向弥散混合系数计算公式： 流固相传质系数计算公式：15流固相传热系数计算公式：管外沸腾水给热系数计算方法模型参数的计算公式 16模型的数值求解 （1）预测公式17（2）校正公式1模型的数值求解 18（2）校正公式2模型的数值求解 19（3）固相方程采用一阶中心差分模型的数值求解 20预测和校正方程消去 的点。件，消去 的点。则可用 代替，从而离散为新的预测和校正差分方程，代入用一阶中心差分离散的边界条（4）边界条件的处理模型的数值求解 原方程中项为不

4、定项，根据L Hospital法边界条件用一阶中心差分离散，再分别用上述21计算框图求解固相浓度和温度方程操作条件：T0,T,Vsp,进口气体组成。轴径向分段数N,M求解气相浓度和温度校正公式求解气相浓度和温度预测公式jN结束打印该截面气固相浓度和温度分布k=0j=0k=0k=1j=j+0.5k=1j=j+0.5k=0否是22计算实例 上海石化总厂化工厂采用的氧气法环氧乙烷合成路线，属于美国SD公司技术。环氧乙烷设计生产能力为 12万吨/年核心设备反应器是立式列管固定床反应器，壳体走蒸汽，反应的原料气走管内。反应器特性和操作条件见下表23表 环氧乙烷合成反应器特性和操作条件催化剂填充高度7.0

5、0m反应管内径31.3mm列管数8821催化剂外形尺寸6.52.56mm催化剂装填量55.44ton空速4265.625h1反应压力2.00MPa原料气进口温度183.5饱和蒸汽压力2.45MPa饱和蒸汽温度225.624续表 环氧乙烷合成反应器特性和操作条件25模型预测值与工业实际值的比较出口气体组成（mol-%）预测值实际值ET22.5622.65O25.225.32EO2.292.21H2O1.331.45CH462.8162.60CO25.795.77出口气体温度（）228.5228.6空时产率gEOLcat-1h-1188.851188.856选择率（）81.781.726模型预测值

6、与工业实际值的比较由图可以看出：模型预测值与工业实际值十分吻合。反应器模型能够准确描述反应器内环氧乙烷合成过程，能够全面反应操作条件对反应的影响。 预测值实际值27计算结果气相温度分布 z0.0000.1670.3330.5000.6670.8331.0000.00.10.20.30.40.50.60.70.80.91.0183.50221.34228.60229.75229.77229.59229.40229.22229.06228.91228.78183.50221.34228.59229.74229.74229.58229.39229.21229.05228.90228.76183.50

7、221.37228.55229.70229.72229.54229.35229.18229.01228.87228.73183.50221.41228.48229.61229.63229.46229.27229.10228.94228.80228.66183.50221.48228.40229.51229.52229.36229.18229.01228.85228.71228.58183.50221.57228.31229.38229.40229.24229.06228.90228.75228.61228.49183.50221.68228.23229.27229.29229.13228.96

8、228.80228.65228.52228.4028计算结果固相外表面温度分布 z0.0000.1670.3330.5000.6670.8331.0000.00.10.20.30.40.50.60.70.80.91.0206.00227.64232.81233.28233.11232.74232.37232.05231.75231.48231.23210.29227.19230.19231.33231.15230.89230.63230.40230.19230.00229.82207.68227.48232.13232.65232.41232.08231.75231.45231.19230.9

9、4230.72212.01227.04230.35230.72230.56230.34230.11229.91229.72229.55229.39212.30227.02230.33230.70230.54230.30230.07229.86229.67229.50229.34216.42226.59228.73228.98228.88228.74228.60228.47228.32228.24228.13219.92226.21227.54227.69227.64227.55227.46227.38227.30227.24227.1729计算结果气相乙烯浓度分布 z0.0000.1670.3

10、330.5000.6670.8331.0000.00.10.20.30.40.50.60.70.80.91.0.25060.24835.24539.24243.23961.23695.23444.23205.22979.22764.22558.25060.24835.24539.24243.23961.23695.23444.23205.22979.22764.22558.25060.24835.24539.24243.23961.23695.23444.23205.22979.22764.22558.25060.24835.24539.24243.23961.23695.23444.2320

11、5.22979.22764.22558.25060.24835.24539.24243.23961.23695.23444.23205.22979.22764.22558.25060.24835.24539.24243.23961.23695.23444.23205.22979.22764.22558.25060.24835.24539.24243.23961.23695.23444.23205.22979.22764.2255830计算结果固相外表面乙烯浓度分布 z0.0000.1670.3330.5000.6670.8331.0000.00.10.20.30.40.50.60.70.80.

12、91.0.25030.24798.24493.24198.23919.23656.23407.23171.22947.22733.22529.25023.24799.24499.24204.23925.23661.23412.23175.22950.22736.25532.25027.24798.24495.24200.23921.23658.23409.23172.22948.22734.22530.25021.24799.24501.24206.23926.23662.23413.23176.22951.22737.22533.25020.24799.24501.24206.23927.2

13、3663.23413.23176.22951.22737.22533.25013.24801.24506.24211.23921.23667.23416.23179.22954.22740.22536.25006.24802.24509.24214.23934.23669.23419.23182.22956.22742.2253731计算结果气相二氧化碳浓度分布 z0.0000.1670.3330.5000.6670.8331.0000.00.10.20.30.40.50.60.70.80.91.0.04720.04802.04922.05047.05167.05282.05392.05498

14、.05600.05699.05794.04720.04802.04922.05047.05167.05282.05392.05498.05600.05699.05794.04720.04802.04922.05047.05167.05282.05392.05498.05600.05699.05794.04720.04802.04922.05047.05167.05282.05392.05498.05600.05699.05794.04720.04802.04922.05047.05167.05282.05392.05498.05600.05699.05794.04720.04802.04922

15、.05047.05167.05282.05392.05498.05600.05699.05794.04720.04802.04922.05047.05167.05282.05392.05498.05600.05699.0579432计算结果固相外表面CO2浓度分布 z0.0000.1670.3330.5000.6670.8331.0000.00.10.20.30.40.50.60.70.80.91.0.04729.04816.04942.05066.05185.05299.05409.05514.05615.05713.05807.04731.04816.04938.05063.05182.05296.05406.05511.05613.05711.05806.04729.04816.04940.05065.05184.05298.05408.05513.05614.05712.05807.04732.04815.04937.0506