干空气吹扫干燥法在输气管道中的应用

除水干燥是提高输气质量，预防水合物形成的重要环节，也是输气管道水试压后应进行的重要工序，以涩宁兰输气管道9．5km，水试压段采用干空气吹扫法进行了作水干燥试验为例，介绍了干空气吹扫干燥的过程，对管道除水效果及除水干燥中露点的变化进行了分析， 结果表明，天然气管道应用干空气吹扫干燥法具有经济，工艺过程易控制等优点，适合在输气管道中推广应用。

The Application of Dry Air Pigging/Drying Method in Gas Transmission Pipeline

Dewatering/drying technology, which can provide a quality gas transported and prevent hydrate from forming,is a key procedure that conducts after water pressure testing. Take the dewatering/drying test as an example, which has been carried out with the dry air pigging/drying method in Sebei-Ningxia-Lanzhou Gas Transmission Pipeline,the paper introduces the process of dry air pigging/drying in a 9. 5 km water pressure testing pipe section of the line. The analysis on dewatering result and the variation of water dew point during dewatering/drying is made. The results indicate that the dry air pigging/drying method is cost-effective and the process is easy to control,suitable to apply in gas transmission pipeline.