【作者】 柳爱华；

【导师】 郭睿威； 周豪；

【作者基本信息】 天津大学 ， 化学工程， 2008， 硕士

【摘要】 天然气蒸汽转化制甲醇是甲醇生产的一种重要方法,在我国天然气副产地区有着很多的装置。但由于受限于二氧化碳量的不足,产量即便是在天然气满负荷状态下仍与设计产量有一定的差距,对装置的达标以及效益影响巨大;如何利用现有装置和乙烯厂有利条件,进行技术改造和技术创新,优化配置资源,使甲醇装置产能和收率得以大幅提高,以及如何采用新技术,新工艺进行装置扩能改造并降低投资成本成为一个重要的课题。本文结合新疆独山子甲醇装置生产和发展前景,探讨了甲醇装置通过回收二氧化碳来提高甲醇合成工序二氧化碳加入量以提高甲醇产量和收率的可行性;提出了通过优化独山子合成气资源和增加转化二段炉等措施来提高现有装置生产负荷,最大程度降低投资,大幅提高甲醇装置生产能力的新思路。对二氧化碳回收效益进行了核算,阐述了二氧化碳回收的可行性和必要性,对甲醇扩能部分进行了物料衡算,对扩能改造提供了数据支持。具体解决思路如下。本文主要针对现有装置合成气组分碳组分不足难题,提出如下具体补碳措施:烟气中回收二氧化碳,采取转化前加或后加法来改变合成气组分;回收制氢装置脱附气,采取转化前加或后加法来改变合成气组分;利用变压吸附将转化后工序部分转化气中的碳组分和氢气分离,氢气外卖,碳组分送至合成工序。针对装置生产能力偏低的问题,提出了装置的扩能改造思路,具体措施如下:增加纯氧二段转化炉,充分利用制氢装置脱附气;各增加一台备用压缩机,提高压缩工序输气能力;并联一套合成系统,包括合成塔、入塔气预热器、甲醇水冷器、高效分离器;精馏进行板式塔改造,更换机泵,扩大储罐,增加换热设备。更多还原

【Abstract】 The process of natural gas steam reforming is an important method to produce methanol. And there are lots of equipments in the areas which are rich in natural gas in our country. However, limited by the insufficiency of carbon dioxide, the actual production still has a certain difference with the designed yield even though the natural gas is in the condition of full load, which greatly hinders the full development and the benefits of the equipments; therefore, it becomes an important task how to use the existing equipments and the advantages of ethylene factory, realize technology improvement and innovation, optimize the resource allocation in order to largely improve the production and benefits of the methanol equipments, and how to employ new technology and new process in order to expand the production of the plant and reduce the cost of investment.Taking into account the production background and the developing perspective, this paper discusses a method to increase the production and yield of methanol by recovering carbon dioxide to raise the amount of carbon dioxide in the process of methanol synthesis, introduces measures to improve the productive load of the existing plants, reduce the investment to the greatest extent, and sharply increase the productivity of the plants by optimizing the resource of synthetic gas in Dushanzi and increasing secondary reformers. This paper also calculates the recovery benefits of carbon dioxide, elaborates the feasibility and necessity of the recovery of carbon dioxide, and calculates material balances that providing dates for the transformation and expanding production .The detailed solutions are as follows:This paper puts forward these increasing carbon measures in order to solve the problem that’s the lack of carbon component in synthesis gases in this plant.Recovering carbon dioxide from the flue gases or desorption gases of the hydrogen production plant,then add it before or after the conversion process in order to change the components of the synthesis gas;The carbon component and the hydrogen component in part of conversion gases will be separated by using pressure-swing absorber after the conversion process, the hydrogen will be sold and the carbon component will be sent to synthesis process.This paper puts forward the train of thought to solve the problem that the productivity of the plant is low. These measures will be took:Increasing a secondary pure oxygen reformer, making good use of the desorption gases of the hydrogen production plant; Respectively increasing a spare compressor in order to enhance the working ability of the compression process; Paralleling a set of syntheses systems, including a syntheses tower, a entering tower gas pre-heater, a methanol cooler and a highly effective separator; Distillation process will transform the tray tower, replace new pumps , enlarge the tank and increase new heat exchange equipments.更多还原