Drying process of Central Asian Natural Gas Pipeline

Due to complex terrain, high altitude difference along the Central Asian Gas Pipeline and existed residual water at low point of pipe after purging, the Pipeline has to be dried. The author contrasts the treatment requirements and the construction period of the dry-air drying and vacuum drying. Results indicate that because the drying period mainly depends on the residual water volume of the pipeline after pressure test, the effect of foam pig, the displacement of the air compressor and the final dew point requirements, considering the drying requirements of the Pipeline, construction period and effects, the dry-air drying method with slight external factor and high drying effect is the final choice. The dry-air drying equipments adopted in the Pipeline are consisted of air compressors, dryers, dewpoint meters, pig launching chamber, trap and quick opening closure. This paper provides the procedures of the field construction equipment installation and construction.