套管环空保护液的研究与应用

Research and Application of Annular Protective Fluid

在冀东海上注水井无套压注水后,为了保护套管不受腐蚀以及井下注水封隔器能够安全起出的需要,在套管环空需要注入环空保护液。基于套管和油管的腐蚀机理和防腐机理,设计出了套管环空保护液的主要添加剂,形成了套管环空保护液的基础配方,并通过对不同类型的除氧剂、缓蚀阻垢剂和杀菌剂的优选及加量调整,研制出了适用于南堡油田海上施工的套管环空保护液。评价结果表明:该保护液的稳定性好,杀菌率大于95%,密度范围宽(1.00～1.15g/cm3),对钢片的腐蚀性低,腐蚀速率低于0.05mm/a,能在井下对套管起到保护作用。目前该保护液已在南堡油田应用3口井,现场施工顺利。

The annular protective fluid must be applied to protect the casing from corrosion and help the waterflood packer come out safely.This paper introduced the formulation and evaluation of an annular protective fluid based on the optimization and adjustment of oxygen scavenger anti-corrosive agent and bactericidal agent.Laboratory evaluation shows that this annular protective fluid has good stability superior bactericidal performance(aseptic rate > 95%) and very low corrosion to steel(corrosion rate < 0.05 mm/a).The annular protective fluid has the density that can be adjusted between 1.00 g/cm3 and 1.15 g/cm3,the application in 3 wells in Nanpu oil field is very successful.