邻法苯酐装置的蒸汽伴热设计浅析  

Brief Analysis on Steam Tracing Design for Ortho Phthalic Anhydride Plant

作　　者：罗辑 Luo Ji(China Chengda Engineering Co.,Ltd.,Chengdu 610041,China)

机构地区：[1]中国成达工程有限公司,四川成都610041

出　　处：《化工设计》2024年第3期47-50,2,共5页Chemical Engineering Design

摘　　要：苯酐的熔点较高,在生产过程中,一旦介质温度低于熔点,液相苯酐将在管道和设备内结晶,发生堵塞。由于粗苯酐中有杂质邻苯二甲酸的存在,所需伴热温度需达250℃,通常选用内管焊缝隐蔽型夹套管(全夹套)伴热。本文分别介绍了苯酐装置中管道、设备管口和膨胀节的夹套伴热和伴管伴热方式。其中,管道伴热部分着重介绍了普通管道夹套伴热的两种形式:半夹套和全夹套,以及管道试验压力的选取。设备部分介绍了3种常见的设备管口伴热形式:普通管口夹套伴热、PAD管口夹套伴热及PAD管口半管伴热。另外,还介绍了管道膨胀节的伴热方式。最后,针对苯酐装置蒸汽伴热用户较多的实际情况,比较了集成式蒸汽分配台和凝液回收站与传统形式的优劣。The melting point of phthalic anhydride is relatively high.In the production process,once the medium temperature is below the melting point,liquid phase phthalic anhydride will crystallize in pipelines and equipment,causing blockage.Due to the presence of impurities such as phthalic acid in crude phthalic anhydride,the required heat tracing temperature needs to reach 250°C.Generally,the concealed jacket(full jacket)is used for heat tracing with inner pipe welds.This paper introduces the jacket heat tracing and pipe heat tracing methods for pipelines,equipment nozzles and expansion joints in the phthalic anhydride plant.The pipeline heat tracing section focuses on the two forms of ordinary pipeline jacket heat tracing,semi jacket and full jacket,as well as the selection of pipeline test pressure.This paper introduces the calculation method for the number of heat tracing pipes in high temperature and large diameter pipelines where table lookup is not possible.The equipment section introduces three common forms of equipment nozzle heat tracing:ordinary nozzle jacket heat tracing,PAD nozzle jacket heat tracing and PAD nozzle half pipe heat tracing.In addition,the heat tracing method of pipeline expansion joints is also introduced.Finally,in response to the actual situation of a large number of steam tracing users in the phthalic anhydride plant,the advantages and disadvantages of integrated steam distribution stations and condensate recovery stations are compared with traditional forms.

关 键 词：苯酐 夹套伴热 伴管伴热 集成伴热系统 

分 类 号：TQ051[化学工程]