1、乙醇水精馏塔实验乙醇-水精馏塔实验一、实验目的：1.了解板式精馏塔的结构和操作。2.学习精馏塔性能参数的测量方法，并掌握其影响因素。二、实验内容:1.测定精馏塔在全回流条件下,稳定操作后的全塔理论塔板数和总板效率。2.测定精馏塔在部分回流条件下,稳定操作后的全塔理论塔板数和总板效率。三、实验原理： 对于二元物系，如已知其汽液平衡数据，则根据精馏塔的原料液组成，进料热状况，操作回流比及塔顶馏出液组成，塔底釜液组成可以求出该塔的理论板数NT.按照式1可以得到总板效率ET,其中NP为实际塔板数。ET （1）部分回流时，进料热状况参数的计算式为 （2）式中： tF 进料温度， 。 tBP 进料的泡点温
2、度， 。 Cpm 进料液体在平均温度（tF+ tP）/2下的比热，kJ/（kmol ） rm 进料液体在其组成和泡点温度下的汽化潜热，kJ/kmol kJ/（kmol ） （3） kJ/kmol （4）式中： CP1， CP2 分别为纯组份1和组份2在平均温度下的比热，kJ/（kg ）。 r1,r2 分别为纯组份1和组份2在泡点温度下的汽化潜热，kJ/kg。M1，M2分别为纯组份1和组份2的摩尔质量，kJ/kmol。x1,x2分别为纯组份1和组份2在进料中的摩尔分率。四、实验装置基本情况:1实验设备流程图（如图1所示）：图1 精馏实验装置流程图1-储料罐；2-进料泵；3-放料阀；4-加热器；5
3、-直接进料阀； 6-间接进料阀；7-进料流量计；8-高位槽；9-玻璃观察段； 10-精馏塔；11-塔釜取样阀；12-釜液放空阀；13-塔顶冷凝器； 14-回流比流量计；15-塔顶取样阀；16-塔顶液回收罐； 17-放空阀；18-冷却水流量计；19-塔釜储料罐；20-塔釜冷凝器； 21-第8块板进料阀；22-第9块板进料阀；23-第10块板进料阀； 24-液位计；25-料液循环阀；26-釜残液出料阀;27-进料入口阀；28-指针压力表2.实验设备主要技术参数：精馏塔实验装置结构参数见表1： 表1 精馏塔结构参数名称直径（mm）高 度（mm）板间距（mm）板 数(块)板型、孔径（mm）材 质塔体7
4、63.510010011筛板2.0不锈钢塔釜2202400不锈钢塔顶冷凝器893.5600不锈钢塔釜冷凝器573.5300不锈钢表2 乙醇水 t-x-y 关系 (以乙醇摩尔分率表示，x-液相，y-气相 )摩尔分数x摩尔分数yt/0.000 0.000 1000.050 0.310 90.60.100 0.430 86.40.200 0.520 83.20.300 0.575 81.70.400 0.614 80.70.500 0.657 79.90.600 0.698 79.10.700 0.755 78.70.800 0.820 78.40.894 0.894 78.150.950 0.94
5、2 78.31.000 1.000 78.3乙醇沸点: 78.3; 水沸点:100.0.3实验仪器及试剂：（1）实验物系：乙醇水（本试验也可用乙醇-正丙醇物系）；（2）实验物系纯度要求: 化学纯或分析纯； （3）实验物系平衡关系见表2；（4） 实验物系浓度要求: 15-25(乙醇质量百分数)，浓度分析使用酒精计，酒精计为体积分数， 通过查酒精体积分数、质量分数、密度对照表可得酒精的质量分数W，通过质量分率求出摩尔分率(X)，公式如下: 乙醇分子量46; 水分子量B183实验设备面板图（如图2所示）：图2 精馏设备仪表面板图五、实验方法及步骤： 1.实验前检查准备工作： 配制一定浓度(质量浓度
6、20左右)的乙醇水混合液(总容量25升左右),倒入储料罐中。打开进料入口阀27，其余阀门关闭，启动进料泵2，打开料液循环阀25，使料液混合均匀，混合均匀后将料液循环阀25打至半开，将直接进料阀全开，放空阀12全开，进行进料，一般在塔釜总高2/3处。然后关闭进料阀门和进料泵。2. 实验操作：(1)全回流操作： 打开塔顶冷凝器进水阀门,保证冷却水足量（160L/h即可）。 记录室温。接通总电源开关（220V）。 调节加热电压约为150伏, 待塔板上建立液层后再适当加大电压至170V，使塔内维持正常操作。 当各块塔板上鼓泡均匀后,保持加热釜电压不变, 在全回流情况下稳定20分钟左右。期间要随时观察塔
7、内传质情况直至操作稳定。然后分别在塔顶、塔釜取样口用100ml量筒同时取样，通过酒精计分析样品浓度。(2)部分回流操作：打开间接进料阀门和进料泵，调节转子流量计, 以3.0-4.0（Lh)的流量向塔内加料，打开进料加热开关，调节到合适的进料温度，用回流比流量计调节回流比为 R3 ，馏出液收集在塔顶液回收罐中。塔釜产品经冷却后由溢流管流出,收集在容器内。待操作稳定后,观察塔板上传质状况,记下加热电压、塔顶温度，塔釜压力等有关数据,整个操作中维持进料流量计读数不变,分别在塔顶、塔釜和进料三处取样,用酒精计其浓度并记录下进塔原料液的温度。 (3)实验结束取好实验数据并检查无误后可停止实验，此时关闭进
8、料阀门和加热开关，关闭回流比流量计阀门。 停止加热后10分钟再关闭冷却水,一切复原。根据物系的 t-x-y 关系,确定部分回流条件下进料的泡点温度，并进行数据处理。六、实验注意事项：1.由于实验所用物系属易燃物品，所以实验中要特别注意安全,操作过程中避免洒落以免发生危险。2.本实验设备加热功率由仪表自动调节，注意控制加热升温要缓慢，以免发生爆沸(过冷沸腾)使釜液从塔顶冲出。若出现此现象应立即断电，重新操作。升温和正常操作过程中釜的电功率不能过大。3.开车时要先接通冷却水再向塔釜供热，停车时操作反之。4.检测浓度使用酒精计，使用方法见说明书 。5.为便于对全回流和部分回流的实验结果(塔顶产品质量
9、)进行比较, 应尽量使两组实验的加热电压及所用料液浓度相同或相近。连续开出实验时, 应将前一次实验时留存在塔釜、塔顶、塔底产品接受器内的料液倒回原料液储罐中循环使用。七、实验数据记录表4 精馏实验原始数据实际塔板数：11 实验物系：乙醇-水 全回流：R = ，塔釜压力 = kPa部分回流：R =3 进料量：4 l/h进料温度：60 塔顶组成塔釜组成塔顶组成塔釜组成进料组成体积分数附录 酒精体积分数、质量分数、密度对照表体积分数质量分数体积分数质量分数体积分数质量分数0033.427.521766.859.01810.10.079133.527.607866.959.12230.20.15823
10、3.627.69436759.22660.30.237333.727.780767.159.3310.40.316333.827.86767.259.43540.50.395633.927.953267.359.53980.60.47483428.039867.459.64440.70.55434.128.126467.559.74890.80.633334.228.21367.659.85420.90.712634.328.299667.759.958910.791834.428.386367.860.06361.10.871234.528.472967.960.16841.20.95053
11、4.628.566860.27331.31.029934.728.646768.160.37871.41.109234.828.733568.260.48391.51.138634.928.820268.360.58961.61.26813528.907168.460.69461.71.347535.128.993968.560.80051.81.42735.229.081168.660.90641.91.506535.329.16868.761.011621.58635.429.255268.861.11762.11.665535.529.342168.961.2232.21.745135.
12、629.42916961.32912.31.824735.729.516469.161.43532.41.904335.829.603469.261.54152.51.983935.929.690869.361.64712.62.06363629.777869.461.75352.72.143336.129.865369.561.85992.82.22336.229.952769.661.96642.92.302736.330.039869.762.072932.382536.430.127369.862.17883.12.462236.530.214969.962.28553.22.5423
13、6.630.30247062.39223.32.621836.730.3970.162.4993.42.701636.830.477370.262.60583.52.781536.930.564970.362.71273.62.86143730.652570.462.81963.72.941337.130.740270.562.92673.83.021237.230.827970.663.0333.93.101237.330.91670.763.140243.181137.431.003870.863.24744.13.261137.531.091670.963.35464.23.341137
14、.631.17947163.46194.33.421137.731.267371.163.56934.43.501237.831.355571.263.67684.53.581337.931.443471.363.78434.63.66143831.531371.463.89184.73.741538.131.619371.564.00024.83.821638.231.707671.664.10794.93.901838.331.795971.764.215653.981938.431.88471.864.32345.14.062138.531.972171.964.43135.24.142
15、438.632.06057264.53295.34.222638.732.14972.164.64725.44.302838.832.237172.264.7565.54.383138.932.325472.364.8645.64.46343932.413972.464.97315.74.543739.132.502572.565.08135.84.62439.232.591172.665.19035.94.704439.332.679472.765.299464.784839.432.768172.865.40796.14.865139.532.856872.965.51646.24.945
16、639.632.94557365.62576.35.025939.733.034373.165.7356.45.106439.833.122773.265.84456.55.186839.933.211673.365.95326.65.26734033.300473.466.06286.75.347840.133.389373.566.17246.85.428340.233.478273.666.28216.95.508940.333.567573.766.391875.589440.433.656573.866.50097.15.670140.533.745573.966.61087.25.
17、750640.633.83457466.72077.35.831240.733.923674.166.83077.45.911840.834.013174.266.94087.55.992540.934.102274.367.0517.66.07324134.191474.467.16127.76.153941.134.280574.567.27147.86.234641.234.370174.667.38257.96.315341.334.459774.767.49386.396141.434.54974.867.60348.16.476841.534.638374.967.7148.26.
18、557741.634.7287567.82468.36.638441.734.817875.167.93528.46.719241.834.902775.268.0468.56.800141.934.996675.368.15768.66.8814235.086575.468.26848.76.961842.135.176375.568.37948.87.042742.235.266275.668.49048.97.123742.335.356275.768.601497.204642.435.446175.868.71349.17.285542.535.536175.968.82469.27
19、.366542.635.62627668.93589.37.447542.735.716276.169.04729.47.528542.835.806376.269.15949.57.609542.935.896476.369.27089.67.69054335.986676.469.38329.77.771643.136.076876.569.49559.87.852643.236.167476.669.60739.97.933743.336.258176.769.719108.014843.436.348376.869.831610.18.10643.536.438776.969.9443
20、10.28.177143.636.52947770.056210.38.258343.736.620277.170.169110.48.339543.836.710677.270.28210.58.420743.936.801177.370.394910.68.5024436.89277.470.507910.78.583244.136.982977.570.62110.88.664544.237.073877.670.734210.98.745844.337.164477.770.8475118.827144.437.255477.870.960811.18.908444.537.34657
21、7.971.074211.28.989744.637.43767871.187611.39.071144.737.528778.171.301211.49.152444.837.619578.271.415611.59.233844.937.710778.371.529211.69.31524537.801978.471.64311.79.396645.137.893278.571.756811.89.478145.237.984578.671.871511.99.559545.338.075878.771.9855129.64145.438.167278.872.099512.19.7225
22、45.538.258678.972.214412.29.80445.638.3547972.328612.39.885645.738.441979.172.442912.49.967145.838.533479.272.55812.510.048745.938.624979.372.672412.610.13034638.716579.472.787712.710.211846.138.808179.572.902212.810.293546.238.900279.673.017712.910.375146.338.991979.773.13321310.456846.439.08479.87
23、3.24813.110.538446.539.175879.973.362813.210.620146.639.26768073.478613.310.701846.739.359880.173.594413.410.783646.839.451780.273.710313.510.865346.939.54480.373.826313.610.9474739.63680.473.942313.711.028847.139.728480.574.058513.811.110647.239.820480.674.173813.911.192547.339.912880.774.29011411.
24、274347.440.005380.874.406414.111.356147.540.097580.974.522914.211.437947.640.198174.639414.311.519847.740.282781.174.75614.411.601747.840.375381.274.873514.511.683647.940.467681.374.990214.611.76555042.425281.475.107914.711.847450.142.519281.575.224814.811.929450.242.612881.675.341814.912.011450.342
25、.706881.775.45971512.093450.442.80181.875.576915.112.175450.542.894781.975.694915.212.257450.642.98888275.812215.312.339450.743.083182.175.930515.412.421450.843.177382.276.047915.512.503550.943.272182.376.166315.612.58565143.365682.476.284815.712.667751.143.459982.576.402515.812.749851.243.554482.676.521115.912.83251.343.648982.776.63991612.914151.443.743482.876.758716.112.996351.543.837982.976.8767
