碳五分离装置长周期运行的瓶颈及对策

发布时间：2018-05-07 12:50

本文选题：碳五分离装置 + 长周期运行　；参考：《北京化工大学》2015年硕士论文

【摘要】：中国石化北京燕山分公司新建碳五分离装置采用中石化自主知识产权技术建成,以燕山石化乙烯装置副产碳五馏份为原料,设计负荷15万吨/年,主要产品为异戊二烯、间戊二烯和双环戊二烯。利用好碳五资源是降低乙烯成本的重要措施之一,也为燕山石化异戊橡胶装置提供原料,支持了燕山石化核心业务的发展,改善了燕山石化的产品结构。本文针对燕山石化碳五分离装置在建成后首次运行期间出现的问题,主要包括系统聚合严重,第二萃取塔运行周期短,溶剂二甲基甲酰胺(DMF)水解严重,异戊二烯损失偏高等影响装置长周期运行的问题,阐明了原因并进行了机理分析,进而提出了相应的解决方法,并对改造后再次运行的情况进行了分析。在保证产品质量、收率的前提下,首要延缓异戊二烯的聚合速率,降低脱重塔(C102塔)以及萃取系统的聚合程度；其次随着装置运行时间的延长,装置内聚合物难免会增加,因此也要保证装置在较长时间的运行后依然能稳定运行;最后还要维持循环溶剂DMF的品质,降低水解程度和排放损失,以保证循环溶剂系统稳定运行。针对上述问题逐一改进之后,碳五分离装置在第二次运行期间产品质量均达标,能耗最低为218.7千克标油/吨原料,低于设计值226.8千克标油/吨原料。萃取系统聚合程度明显减轻,使异戊二烯收率达到84%,较首次开车大幅提高14个百分点,但低于90%的设计值；间戊二烯收率达到92%,超过设计值3个百分点：双环戊二烯收率达到87%,超过设计值1个百分点。循环溶剂(DMF)品质得到改善,溶剂中水含量在500mg/kg以内。总之,本次技改达到了预期目的,确保了装置长周期稳定运行。
[Abstract]:The newly built carbon 5 separation unit in Beijing Yanshan Branch of Sinopec was built using Sinopec's independent intellectual property technology. The by-product of Yanshan Ethylene Plant was used as raw material and the design load was 150000 tons / year. The main product was isoprene. M-pentadiene and dicyclopentadiene. Making good use of C _ 5 resources is one of the important measures to reduce ethylene cost, and also provides raw materials for Yanshan Petrochemical isoprene rubber plant, which supports the development of Yanshan Petrochemical's core business and improves the product structure of Yanshan Petrochemical. In this paper, the problems occurred during the first operation of the C _ 5 separation unit in Yanshan Petrochemical Company were discussed, including serious system polymerization, short operation period of the second extraction column and severe hydrolysis of solvent dimethylformamide (DMF). The problems affecting the long period operation of the plant such as high loss of isoprene are explained, the cause and mechanism are analyzed, and the corresponding solutions are put forward, and the reoperation after revamping is analyzed. On the premise of ensuring the product quality and yield, the polymerization rate of isoprene is mainly delayed, the polymerization degree of the extraction system is reduced and the polymerization degree of the descaling tower C102) is reduced. Secondly, with the increase of the operating time of the unit, the polymer in the unit will inevitably increase. Therefore, it is necessary to ensure that the unit can still operate stably after a long period of operation. Finally, it is necessary to maintain the quality of the circulating solvent DMF and reduce the degree of hydrolysis and emission loss in order to ensure the stable operation of the circulating solvent system. After improving one by one of the above problems, the product quality of the carbon-5 separation unit is up to standard in the second operation period, and the lowest energy consumption is 218.7 kg / ton feedstock, which is lower than the design value of 226.8 kg / ton feedstock. The degree of polymerization in the extraction system was obviously reduced, and the yield of isoprene reached 84%, which was 14 percentage points higher than that of the first start-up, but less than 90% of the design value. The yield of m-pentadiene was 92%, which exceeded the design value by 3%. The yield of dicyclopentadiene reached 87% and exceeded the design value by 1%. The quality of circulating solvent (DMF) was improved and the water content in the solvent was within 500mg/kg. In a word, this technical reform has achieved the expected purpose and ensured the long-period stable operation of the device.
【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ221.22

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