LNG深冷管道复合保冷结构的创新与实践

Innovation and Practice of Composite Cold Insulation Structure for LNG Cryogenic Pipeline

某公司二期项目在一期工程预留区域内进行扩建,其主要功能是增加液化天然气(LNG)接收站的储存容量和外输能力。LNG具有超低温存储和输送的特点,因此LNG输送的管道保冷方式以及保冷材料的选取至关重要,该管道的保冷性能关系到LNG接收站的经济效益和运行安全。管道保冷多采取单一的聚异三聚氰酸脂(PIR)保冷结构,阀门法兰等异形件保冷方式采用传统的聚氨酯现场发泡。为了达到低温LNG管道保冷预期效果,结合各类保冷材料的技术参数,多次优化施工方案,最终采用PIR加泡沫玻璃复合结构,阀门法兰等异形件的保冷采用气凝胶绝热毡。管道试运行后,保冷效果良好。

The second phase project of a certain company was an expansion carried out within the reserved area of the first phase project,with the main function of increasing the storage capacity and export capacity of the LNG(liquefied natural gas) receiving station.LNG had the characteristics of ultra-low temperature storage and transportation,so the selection of pipeline insulation methods and insulation materials for LNG transportation was crucial.The insulation performance of the pipeline was related to the economic benefits and operational safety of LNG receiving stations.Pipeline insulation mostly adopted a single PIR insulation structure,while valve flanges and other shaped parts were insulated using traditional polyurethane on-site foaming.In order to achieve the expected effect of cold insulation of low temperature LNG pipeline,the construction scheme was optimized for many times in combination with the technical parameters of various cold insulation materials.PIR plus foam glass composite structure was finally used for cold insulation of pipeline,and aerogel insulation felt was used for cold insulation of valve flanges and other profiled parts.After the trial operation of the pipeline,the cold insulation effect was good.