Corrosion And Control Of Condensate In Gathering And Conveying Pipelines In Puguang Gas Field

Puguang Gas Field,which is the first developed whole-block marine-facies highly sour gas field in China,is characterized by substantially high content of hydrogen sulfide and carbon dixode that may incurs serious corrosion to garthering and tranportation pipelines.And the pipelines run in long distance covering mountaineous regions of quite complicated topographic conditions,yet these regions are highly populated.Leakage of pipelines would in any case be a fatal threat to the local villagies and communities.However,the smart detection data shows that local corrosion does exist in the pipelines.Taking the factual condition of the pipelines in the Gas Field and the element of topographic conditions into consideration,the qualitative analysis on gas-liquid fluid dynamics and thermodynamic calculation are carried out using the pipeline from P303 Garthering Station to Master Garthering Station as a case study sample,the gas-liquid fluid dynamics and the water condensation point in the pipeline are thus confirmed.Through these studies,the flowing distribution of corrosion inhabitor inside of the pipeline is well understood.The probability of corrosion generation in the top area of the pipeline is proved by in-room simulation,as well as the corrosion structure and the durability of corrosion inhabitation film on both top and bottom of the pipeline.And the results of these lab tests are carefully compared with the factual on-cite detection data.The sensitive corrosion area of the pipeline in P303 Garthering Station is asertained on the comprehensive study of the corrosion inhabitor distribution,thermodynamic calculations and the lab tests,in line with the factual elevation,rout and burial condition of the pipeline.By these efforts,the methodology on discernment of the weak area of corrosion inhabitor distribution is established;and the calculation toolkit is developed to predict the state of gas inside of the pipeline.Also the corrosion sensitive area on top part of the pipeline in Puguang Gas Field is found out and the corrosion risks are recognized with the formation of a comprehensive evaluation system,which facilitates the key points corrosion survelience and inhabitation of pipelines in Puguang.