乙酸乙酯反应器设计

青海大学《化工过程设备设计Ⅱ》设计说明书设计题目：年产2.76×103t乙酸乙酯反应器设计班级：2013级化工2班姓名：邬天贵学号：1320103130前言乙酸乙酯，又称醋酸乙酯，分子式C4H8O2。它是一种无色透明易挥发的可燃性液体，呈强烈清凉菠萝香气和葡萄酒香味。乙酸乙酯能很好的溶于乙醇、氯仿、乙醚、甘油、丙二醇和大多数非挥发性油等有机溶剂中，稍溶于水，25℃时，1ml乙酸乙酯可溶于10ml水中，而且在碱性溶液中易分解成乙酸和乙醇。水能使其缓慢分解而呈酸性。乙酸乙酯与水和乙醇都能形成二元共沸混合物，与水形成的共沸物沸点为70.4℃，其中含水量为6.1%（质量分数）。与乙醇形成的共沸物沸点为71.8℃。还与7.8%的水和9.0%的乙醇形成三元共沸物，其沸点为70.2℃。乙酸乙酯应用最广泛的脂肪酸酯之一，具有优良的溶解性能，是一种较好的工业溶剂，已经被广泛应用于醋酸纤维、乙基纤维、氯化橡胶、乙醛纤维树脂、合成橡胶等的生产，也可用于生产复印机用液体硝基纤维墨水，在纺织工业中用作清洗剂，在食品工业中用作特殊改性酒精的香味萃取剂，在香料工业中是最重要的香味添加剂，可作为调香剂的组分，乙酸乙酯也可用作黏合剂的溶剂，油漆的稀释剂以及作为制造药物、染料等的原料。目前，国内外市场需求不断增加。在人类不断注重环保的今天，在涂料油墨生产中采用高档溶剂是大势所趋。作为高档溶剂，乙酸乙酯在国内外的应用在持续稳定的增长，在建筑、汽车等行业的迅速发展，也会带动对乙酸乙酯类溶剂的需求。工业生产技术目前全球乙酸乙酯工业生产方法主要有醋酸酯化法、乙醛缩合法、乙醇脱氢法和乙烯加成法等。传统的醋酸酯化法工艺在国外被逐步淘汰，而大规模生产装置主要采用后三种方法，其中新建装置多采用乙烯加成法。本设计采用醋酸酯化法。醋酸酯化法在硫酸催化剂作用下，醋酸和乙醇直接酯化生成乙酸乙酯。该工艺方法技术成熟，投资少，操作简单，但缺点是生产成本高、硫酸对设备腐蚀性强、副反应多、产品处理困难、环境污染严重。目前我国大多数企业仍采用醋酸酯化法生产乙酸乙酯。目录一、工艺设计·························································11.1原料液的处理量···············································11.2原料液的起始浓度···············································11.3反应时间与反应体积············································1二、物料衡算·························································2三、热量衡算·························································33.1标准反应热···················································33.2热量衡算·······················································33.3换热计算·····················································5四、反应釜釜体设计··················································54.1反应器的直径与高度·············································54.2筒体的壁厚·····················································74.3反应釜封头厚度·················································8五、反应釜夹套设计···················································85.1夹套DN、PN的确定··············································85.2夹套筒体的壁厚················································95.3夹套筒体的高度················································105.4夹套的封头····················································105.5换热面积校核··················································10六、反应釜釜体及夹套压力试验········································106.1釜体的水压试验················································116.2夹套的液压试验···············································11七、搅拌器··························································127.1搅拌桨的尺寸与安装位置········································137.2搅拌功率的计算················································147.3搅拌轴直径设计················································15八、反应釜附件的选型与尺寸设计······································178.1原料液进料管··················································178.2人孔与手孔····················································178.3支座··························································178.4传动装置······················································178.5机架··························································18九、设计结果一览表·················································18十、设计心得·······················································20参考文献·······················································21一、工艺设计1.1原料液的处理量根据乙酸乙酯的产量可计算出每小时乙酸用量为Q=2.76×103×10388×7200×0.386=11.285kmol/h由于原料液的组分质量比为1:2:1.35所以单位时间处理量为Q0=11.285×60×4.351020=2.888m3/h1.2原料液的起始浓度CA0=11.2852.888=3.908mol/L有质量比可得乙醇和水的起始浓度CB0=3.908×60×246=10.195mol/LCS0=3.908×60×1.3518=17.586mol/L1.3反应时间与反应体积将速率方程转换成转化率的函数CA=CA0(1-XA)CB=CB0-CA0XACR=CA0XACS=CS0+CA0XARA=k1(a+bXA+cXA2)CA02=k1[K-1KXA2-(1+CA0CB0+CS0CA0K)XA+CB0CA0]CA02由上式可得a=CB0CA0=2.609b=-(1+CA0CB0+CS0CA0K)=-5.15c=K-1K=0.658所以：∆=2b2-4ac=4.434则：t=1k1CA0X0dXAa+bXA+cXA2=143.8min所以：VR=Q0(t+t0)=2.888×(143.8+50)60=9.328m3实际体积Vt=VRf=9.3280.6=15.547m3（对于沸腾或鼓泡的液体物料，f可取0.4~0.6《化学反应工程》）二、物料衡算乙酸每小时进料量为11.285kmol/h，根据乙酸的转化率和反应物的初始质量比计算出各物料的进料和出料量。进料：乙醇：Q0=11.285×60×246=29.439kmol/h乙酸乙酯：Q0=0kmol/h水：Q0=11.285×60×1.3518=50.783kmol/h出料：乙酸：Q=11.285-11.285×0.386=6.929kmol/h乙醇：Q=29.439-11.285×0.386=25.083kmol/h乙酸乙酯：Q=11.285×0.386=4.356kmol/h水：Q=50.783+11.285×0.386=55.139kmol/h列表如下：物料进料kmol/h出料kmol/h乙酸11.2856.929乙醇29.43925.083乙酸乙酯04.356水50.78355.139三、热量衡算3.1标准反应热以第一基准为计算基准反应方程式：CH3COOH+C2H5OH→CH3COOC2H5+H2O∆H=n∆Hr0μ+输出niHi-输入niHi各物质的∆Hf0及∆HV(蒸发焓)查得如下：（由《化工工艺设计手册》第四版上册查得）乙酸：∆Hf0=-487.0KJ/mol乙醇：∆Hf0=-277.6KJ/mol∆HV=39.33KJ/mol乙酸乙酯：∆Hf0=-463.3KJ/mol∆HV=32.24KJ/mol水：∆Hf0=-285.9KJ/mol∆HV=40.63KJ/mol∆Hr0=输出μi∆Hf0-输入μi∆Hf0=-（463.3+285.9）+（487.0+277.6）=15.4KJ/mol3.2热量衡算从《化工工艺设计手册》第四版上册查出各组分在各温度段的CP值，经拟合呈线性关系，所以可用内插法求得各物质在反应温度段下的平均CP值。拟合结果如下：乙酸：y=0.1015X+131.25k2=0.9961得CP=137.803J/(mol·k)乙醇：y液=0.4845X+98.9k2=0.9942得CP液=124.678J/(mol·k)y气=0.1558X+61.593k2=0.9998得CP气=75.390J/(mol·k)乙酸乙酯：y液=0.225X+164.8k2=0.9681得CP液=177.038J/(mol·k)y气=0.272X+104.12k2=0.9995得CP气=128.028J/(mol·k)水：y=0.0002X2-0.0136X+75.453k2=0.9968得CP=75.672J/(mol·k)因为进料温度为25℃，所以输入niHi=0，将上述CP值带入计算各组分输出焓值。乙酸：∆H1=n10025Cp液dt=7.161×104KJ/h乙醇：∆H2=n[7825pC液dt+∆HV+10078pC气dt]=1.194×106KJ/h乙酸乙酯：∆H3=n[7725pC液dt+∆HV+10077pC气dt]=1.934×105KJ/h水：∆H4=n(10025Cp液dt+∆HV)=2.553×106KJ/h输出niHi=4.012×106KJ/h∆H总=4.356×15.4×103+4.012×106-0=4.079×106KJ/h∆H总0，所以外界应向系统提供能量。3.3换热计算换热采用夹套加热，设夹套内的过热水蒸气由130℃降到110℃。温差为20℃，忽略热损失，则计算水蒸气的用量如下：水蒸气的