The Technologigal Research Of Oil Well String Resisting Corrosion Of Carbon Dioxide

In wet environment when meeting the suitable temperature and pressure condition carbon dioxide can give rise to the more serious corruption to steel tube causing quickly general corrosion and local corrosion, it even causes oil tube and casing corruption crack, thus it can shorten production life of oil well with huge economic loss. So corruption mechanism and law are researched, rational protective measures are probed, as has vital meaning for pledging production life of oil well and raising oil recovery benefit. This text is based on reservoir geologic feature in Daqing oil field XuJia defensive district, proposing casing protection technology measure is the research objective, electrochemistry basic principles of steels corrosion with carbon dioxide is the foundation, normal tubing and particular steel of oil well engineering are researched, influence law of major factor such as temperature, carbon dioxide DP and gas production flow velocity to every pipe corrosion rate is revealed. By means of testing and analyzing oil well pipe corrosion morphological feature, product composition and microstructure, corrosion mechanism of every pipe is proposed in different environment. The relation between every corrosion law and entity is promulgated, corrosion forecast model is established. Combining extensional situation of Daqing oil field XuJia defensive district, through improving pipe material, resurfacing and injecting retardant, by comprehensive evaluation for protect corrosion measure and technique, engineering feasibility and economic cost of present protect corrosion measure is evaluated, feasibility assessment of present technique applied in DaQing oil field is found. Protect corrosion measure fitting provincial characteristics of DaQing oil field is proposed.Research achievements of this text have the important pragmatic meaning and academic interest for resolving the problem of carbon dioxide eroding oil well tube, prolonging the life of exploration well and oil well, raising carbon dioxide availability efficiency, pledging development and utilization of hydrocarbon reservoir with carbon dioxide including deep zone and the well running job carbon dioxide expulsion TOR technique and carbon dioxide aerating fracture technology etc.