Study on Corrosion Mechanism of Gas Gathering Station Pipeline in Gas Field in Northern Shaanxi
In view of the serious corrosion problem of a gas gathering station in Northern Shaanxi,the composition of natural gas and produced water received by the gas gathering station was analyzed.The average corrosion rate of L245NS carbon steel in different parts of the gas gathering station was measured by weight loss method,and the corrosion product film and pitting pit were characterized.The results show that the content of CO2 and H2S in the received natural gas are 6.33%and 354 mg/m3,respectively,the pH of the received produced water is low,the content of Cl-and scaling cations is high,and the received medium belongs to strong corrosion and scaling medium.The corrosion product film of the incoming pipeline,sewage pipeline and outgoing pipeline is incomplete,and the corrosion degree is mild,severe and mild respectively.The corrosion form is pitting corrosion,mainly CO2 corrosion.The corrosion and scaling products in the incoming pipeline are mainly composed of BaSO4 and CaCO3.The corrosion and scaling products in the sewage pipeline are mainly composed of elemental S,FeCO3 and CaCO3.The main causes of pitting corrosion are the serious scaling of corrosive medium,uneven the distribution of scale on the surface of the pipeline and Cl-and CO2 corrosion.
gas gathering stationL245NS carbon steelpipelinecorrosion mechanism
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万方数据
