Abstract:
As LPG and oil alternative fuel, DME has drawn attentions at present. Physical properties of DME is similar for LPG, and don’t produce combustion gas to damage the environment, so, It can be produced largely. Like methane, DME is expected to become 21st century energy resources., DME is prepared by methanol dehydration, namely, synthetic methanol first and then methanol dehydration to dimethyl etherby methanol dehydration. Methanol dehydration to DME is divided into two kinds of liquid phase and gas-phase process. This design uses a process gas of dimethyl ether prepared by dimethyl. Heating methanol to evaporation, methanol vapor through the γ-AL 2O3 catalyst bed, vapor methanol dehydration to dimethyl etherby. This process is made of methanol process heating, evaporation, dehydration of methanol, dimethyl ether condensation and distillation etc. Completed for the following work:
1) Distillation tower used in separation of dimethyl ether and methanol recovery , column height of tower ,diameter, arrangement of column plate etc; 2) The calculation and selection of heat exchanger, pump;
Key words: dimethyl ether, methanol, process design
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目 录
摘要 前言
化工设计课程设计任务书 ................................................................................................................................ I 前 言 ........................................................................................................................................................... 1 1 文献综述 ....................................................................................................................................................... 1
1.1 二甲醚概述 ........................................................................................................................................ 1
1.1.1 二甲醚的发展现状 ................................................................................................................. 1 1.1.2 二甲醚的传统领域的应用及其拓展 ..................................................................................... 1 1.2国内二甲醚市场简况 ......................................................................................................................... 2
1.2.1现状 .......................................................................................................................................... 2 1.2.2 国内市场预测 ......................................................................................................................... 4 1.3国外二甲醚市场简况 ......................................................................................................................... 5
1.3.1现状 .......................................................................................................................................... 5 1.3.2 国外市场预测 ......................................................................................................................... 6 1.4 原料说明 ............................................................................................................................................ 7 1.6 二甲醚的主要技术指标 .................................................................................................................... 8
1.6.1技术要求 .................................................................................................................................. 8 1.6.2试验方法 .................................................................................................................................. 9
2 DME产品方案及生产规模 ....................................................................................................................... 11
2.1 产品品种、规格、质量指标及拟建规模 ...................................................................................... 11 2.2 产品规格、质量指标 ...................................................................................................................... 11 2.3 产品方案分析及生产规模分析 ...................................................................................................... 12 3 工艺流程介绍 ............................................................................................................................................. 12
3.1生产方法简述 ................................................................................................................................... 12 3.2工艺流程说明 ................................................................................................................................... 14 3.3生产工艺特点 ................................................................................................................................... 16 3.4主要工艺指标 ................................................................................................................................... 16
3.4.1 二甲醚产品指标 ................................................................................................................... 16 3.4.2 催化剂的使用 ....................................................................................................................... 17
4主要塔设备计算及选型 .............................................................................................................................. 17
4.1 汽化塔及其附属设备的计算选型 .................................................................................................. 17
4.1.1 物料衡算 ............................................................................................................................... 17 4.1.2 热量衡算 ............................................................................................................................... 19 4.1.3 理论板数、塔径、填料选择及填料层高度的计算 ........................................................... 21 4.1.4 汽化塔附属设备的选型计算 ............................................................................................... 25 4.2 合成塔及其附属设备的计算选型 .................................................................................................. 26
4.2.1 物料衡算 ............................................................................................................................... 26 4.2.2 合成塔的选取选取： ........................................................................................................... 26 4.2.3 热量衡算及附属设备的选型计算 ....................................................................................... 26 4.3 精馏塔及其附属设备的计算选型 .................................................................................................. 29
4.3.1 物料衡算 ............................................................................................................................... 30 4.3.2 热量衡算 ............................................................................................................................... 30
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4.3.3 理论塔板数的计算 ............................................................................................................... 32 4.3.4 初馏塔主要尺寸的设计计算 ............................................................................................... 32 4.3.5塔径设计计算 ........................................................................................................................ 34 4.3.6 填料层高度的计算 ............................................................................................................... 35 4.3.7 附属设备的选型计算 ........................................................................................................... 35 4.4 回收塔及其附属设备的计算选型 .................................................................................................. 36
4.5.1 物料衡算 ............................................................................................................................... 36 4.4.2 热量衡算 ............................................................................................................................... 38 4.4.3 理论塔板数的计算 ............................................................................................................... 39 4.4.4 回收塔主要尺寸的设计计算 ............................................................................................... 40 4.4.5塔径设计计算 ........................................................................................................................ 41 4.4.6 填料层高度的计算 ............................................................................................................... 42 4.4.7 附属设备的选型计算 ........................................................................................................... 43
致谢 ................................................................................................................................................................. 45 参考文献 ......................................................................................................................................................... 46 附录1.主要设备一览表 ................................................................................................................................. 47
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前 言
二甲醚又称甲醚、木醚氧、二甲，是最简单的脂肪醚重要的甲醇下游产品之一。二甲醚的理化性质比较独特，热植高，无毒、无害，具有潜在的广泛用途，除作为有机化工原料广泛用于制药、染料、农药等，还用于替代氟里昂用作汽溶胶喷射剂和制冷剂，由于其良好的燃料性能，具有实用、通用、环保、安全、质优价廉的优点，最近作为民用代用燃料和柴油代用燃料，二甲醚受到人民的日益重视。
20世纪70年代，二甲醚开始被用作气雾剂，以取代破坏臭氧层的氟里昂。近几年来，在各国寻求清洁燃料的过程中，二甲醚的良好燃烧性能和低污染排放的特性使其日益受到重视。二甲醚作为清洁燃料具备如下特征：（1）资源量丰富，来源广；（2）环境友好，其排放物对环境的影响很小；（3）技术可行、成熟，可在大范围内使用；（4）经济可行，其成本有竞争力；（5）易于实现，其运行所需要的基础设施和现有基础设施基本相容，不需要另装一套装置。
本设计流程简洁明畅，工艺条件温和，操作简易方便。而且设备台数较少，设备制作立足于国内现状，均能在国内制造而不需进口，可大大降低项目投资。按国家现行基本建设政策和市场价格对本项目进行了财务评价计算。工程总投资估算值14300万元，项目的内部收益率所得税前为13.82%，高于基准收益率12%。其它各项效益指标及盈亏平衡分析结果均表明本项目具有很强的抗风险能力。上述各方面问题的研究结果表明，10万吨/年二甲醚项目符合国家产业政策和未来能源市场发展方向，市场预测乐观，工艺方案合理，工艺技术成熟可靠，投资估算和财务评价结果也表明项目经济效益明显。
本设计包括设计说明书和图纸两部分。说明书主要包括工艺流程的确定，物料衡算，热量衡算，工艺设备的设计及选型，厂房平面布置，还有进行初步的经济分析等。图纸包括工艺流程图，主设备图，车间布置平面等。
设计者：武晓佩 2012年11月25日