喇嘛甸油田埋地管道腐蚀机理及防治对策

Corrosion Mechanism and Control Countermeasures of Buried Pipeline in Lamadian Oilfield

通过电镜、X射线衍射分析,以及室内模拟实验技术手段,对喇嘛甸油田埋地管道腐蚀机理进行了分析研究,初步确定了内外腐蚀的主要因素。金属管道内腐蚀主要是三种细菌作用下的电化学腐蚀,占比75%。由于内防腐涂层失效,导致细菌进入形成菌瘤,加快了管道腐蚀,最终导致管道穿孔。外腐蚀的主要原因是喇嘛甸油田土壤电阻率低,土壤腐蚀性强,由于施工、外力破坏、外补口等质量因素,造成外防腐层破损,导致管体土壤中形成电化学腐蚀。为此提出,应加强管道完整性管理,建立全过程质量控制体系,开展管道质量检测和双高管道识别评价,建立埋地管网管理平台;在内腐蚀控制上推广应用新型涂料及内补口配套技术,在外腐蚀控制上推广应用站场区域阴极保护技术。上述措施的应用可以有效控制埋地管道失效率,提高埋地管道运行维护水平。

By using technical measures such as electron microscope,X-ray diffraction analysis,and laboratory simulation experiment,the corrosion mechanism of buried pipelines in Lamadian Oilfield is analyzed.The main corrosion factors are determined preliminarily,and the internal corrosion of metal pipeline is mainly the electrochemical corrosion under the action of three kinds of bacteria,accounting for 75%.Due to the failure of internal anticorrosive coating,bacteria enter and form mycocecidium,the corrosion rate is accelerated,thus finally leading to the pipe perforation.The main reasons of external corrosion are the low soil resistivity and strong soil corrosivity of Lamadian Oilfield.Due to the quality factors such as construction,external force damage,and external joint coating,the damage of outer anticorrosive coating occurs,resulting in the formation of electrochemical corrosion in the soil.Therefore,it is proposed that the pipeline integrity management should be further strengthened,the whole process quality control system should be established,the pipeline quality inspection and double high pipeline identification evaluation should be carried out,and the buried pipe network management platform should be established.In terms of internal corrosion control,the new coating and internal joint coating supporting technology should be popularized.In view of external corrosion control,the station area cathodic protection technology should be promoted,so as to effectively control the failure efficiency of buried pipelines,and improve the operation and maintenance level of buried pipelines.