甲醇合成工段工艺设计

济源职业技术学院毕业设计（论文）(冶金化工系)题目年产十万吨甲醇合成工段工艺设计专业应用化工技术班级化工1001班姓名学号指导教师李晓乐完成日期2012年6月15日～2012年9月30日济源职业技术学院毕业设计（论文）-I-目录摘要······························································································1第一章综述·····················································································21.1甲醇在经济发展中的地位与作用················································21.2甲醇生产相关技术的发展··························································21.3甲醇合成生产方法的综述及选择················································31.3.1高压法··········································································31.3.2低压法··········································································31.3.3中压法··········································································31.3.4合成方法的选择······························································3第二章甲醇合成工段设计···································································42.1甲醇的性质············································································42.1.1甲醇的物理性质······························································42.1.2甲醇的化学性质······························································42.2甲醇合成工段设计···································································62.2.1甲醇合成反应的主要原理及特点·······································62.2.2甲醇合成工艺条件的选择··················································62.2.3工艺流程的确定······························································8第三章工艺计算·············································································103.1甲醇生产的物料平衡计算·························································103.1.1合成塔物料平衡计算·······················································103.2热量衡算··············································································163.2.1甲醇合成塔的热平衡计算·················································163.2.2水冷器热量衡算·····························································19第四章设备的选型···········································································234.1合成塔·················································································234.2辅助设备···············································································254.2.1热交换器······································································254.2.2其它设备······································································25致谢·····························································································27济源职业技术学院毕业设计（论文）-II-参考文献·························································································28附录一甲醇合成流程图·····································································29附录二合成塔·················································································30济源职业技术学院毕业设计（论文）-1-摘要甲醇是一种重要的有机化工原料，应用广泛，可以用来生产甲醛，合成橡胶、甲胺、对苯二甲酸二甲酯、甲基苯烯酸甲酯、氯甲烷、醋酸、甲基叔丁基醚等一系列有机化工产品，而且还可以加入汽油掺扰或代替汽油作为动力燃料以及由用来合成甲醇蛋白。随着当今世界石油资源的日益减少和甲醇单位成本的降低，用甲醇作为新的石化原料来源已经成为一种趋势。此外甲醇还可以用来生产能较好解决能源和污染之间矛盾的“21世纪的绿色燃料”二甲醚（DME）。本文依据年产10万吨甲醇的工艺，设计年产10万吨甲醇的合成工段工艺。关键词：原料气甲醇合成塔合成济源职业技术学院毕业设计（论文）-2-第一章综述1.1甲醇在经济发展中的地位与作用甲醇生产过程比较简单，原料来源多样,煤、石脑油和天然气均可制甲醇。甲醇用途广泛,它的下游产品多达几百种。近年来由于世界各国环保意识的加强,特别是美国国会于1990年11月15日通过清洁空气法修正案以后,甲醇的身价备增,全球甲醇的需求增长加快。甲醇用途广泛，是基础的有机化工原料和优质燃料。主要应用于精细化工，塑料等领域，用来制造甲醛、醋酸、氯甲烷、甲氨、硫酸二甲酯等多种有机产品，也是农药、医药的重要原料之一。甲醇在深加工后可作为一种新型清洁燃料，也加入汽油掺烧。甲醇和氨反应可以制造一甲胺。近年来，随着技术的发展和能源结构的改变，甲醇又开辟了许多新的用途。甲醇是较好的人工合成蛋白的原料，蛋白转化率较高，发酵速度快，无毒性，价格便宜；目前，世界上已有年产10万吨甲醇制蛋白的工业装置在运转，年产30万吨的大型装置已经设计。甲醇是容易输送的清洁燃料，可以单独或与汽油混合作为汽车燃料，用它作为汽油添加剂可起节约芳烃、提高辛烷值的作用，汽车制造业将成为耗用甲醇的巨大部门；由甲醇转化为汽油方法的研究成果，从而开辟了由煤转换为汽车燃料的途径。甲醇是直接合成醋酸的原料。甲醇可直接用于还原铁矿（甲醇可以预先分解为CO、H2，也可以不作预分解），得到高质量的海绵铁。特别是近年来碳一化学工业的发展，甲醇制乙醇、乙烯、乙二醇、甲苯、二甲苯、醋酸乙烯、醋酸酐、甲酸甲酯和氧分解性能好的甲醇树脂等产品，正在研究开发和工业化中。甲醇化工已成为化学工业中一个重要的领域。1.2甲醇生产相关技术的发展（1）二次转化和自转化工艺合成气发生占甲醇装置总投资的50％~60％，所以许多工程公司将其视为技术改进重点。已经形成的新工艺主要是Synetix(前ICI)的先进天然气加热炉转化工艺(AGHR)、Lurgi的组合转化工艺(CR)和Topse的自热转化工艺(ATR)。（2）新甲醇反应器和合成技术大型甲醇生产装置必须具备与其规模相适应的甲醇反应器和反应技术。传统甲醇合成反应器有ICI的冷激型反应器、Lungi的管壳式反应器、Topsdpe的径向流动反济源职业技术学院毕业设计（论文）-3-应器等近期出现的新合成甲醇反应器有日本东洋工程(TEC)的MRF—Z反应器等，而反应技术方面则出现了Lurgi推出的水冷一气冷相结合的新流程。（3）引进膜分离技术的反应技术通常的甲醇合成工艺中，未反应气体需循环返回反应器，而KPT则提出将未反应气体送往膜分离器，并将气体分为富含氢气的气体，前者作燃料用，后者返回反应器。（4）液相合成工艺传统甲醇合成采用气相工艺，不足之处是原料单程转化率低、合成气净化成本高、能耗高。相比之下，液相合成由于使用了比热容高、导热系数大的长链烷烃化合物作反应介质，可使甲醇合成在等温条件下进行。1.3甲醇合成生产方法的综述及选择1.3.1高压法高压法（19.6－29.4MPa）：是最初生产甲醇的方法，采用锌铬催化剂，反应温度360－400℃，压力19.6－29.4MPa。高压法由于原料和动力消耗大，反应温度高，生成粗甲醇中有机杂质含量高，而且投资大，其发展长期以来处于停顿状态。1.3.2低压法低压法（5.0－8.0MPa）：是20世纪60年代后期发展起来的甲醇合成技术。低压法基于高活性的铜系催化剂，其活性明显高于锌铬催化剂，反应温度低（240-270℃）。在较低压力下可获得较高的甲醇收率，且选择性好，减少了副反应，改善了甲醇质量，降低了原料的消耗。此外，由于压力低，动力消耗降低很多，工艺设备制造容易。1.3.3中压法中压法（9.8－12.0MPa）：随着甲醇工业的大型化，如采用低压法势必导致工艺管道和设备较大，因此在低压法的基础上适当提高合成压力，即发展成为中压法。中压法仍采用高活性的铜系催化剂，反应温度与低压法相同，但由于提高了压力，相应的动力消耗略有增加。1.3.4合成方法的选择本设计所采用的合成方法：比较以上三者的优缺点，以投资成本，生产成本，产品收率为依据，选择低压法为生产甲醇的工艺，用CO和H2在加热压力下，在催化剂作用下合成甲醇，其主要反应式为：CO+H2→CH3OH。济源职业技术学院毕业设计（论文）-4-第二章甲醇合成工段设计2.1甲醇的性质2.1.1甲醇的物理性质无色、透明、高度挥发、易燃液体。略有酒精气味。分子式CH3OH、分子量32.04、相对密度0.792(20/4℃)、熔点-97.8℃、沸点64.5℃、闪点12.22℃、自燃点463.89℃、蒸气密度1.11、蒸气压13.33KPa(100mmHg21.2℃)。蒸气与空气混合物爆炸下限6～36.5%。能与水、乙醇、乙醚、苯、酮、卤代烃和许多其他有机溶剂相混溶。遇热、明火或氧化剂易着火。遇明火会爆炸，在空气中甲醇蒸汽的爆炸极限6.0～36.5%（体积）。甲醇是最常用的有机溶剂之一。与水互