45碳钢在HPAM/Na_2CO_3复合驱油系中的腐蚀行为

CORROSION OF TYPE 45 CARBON STEEL IN HPAM AND ALKALINE MIXED FLOODING

研究了 ４５ 碳钢在部分水解聚丙烯酰胺（ Ｈ Ｐ Ａ Ｍ ）碱（ Ｎａ２ Ｃ Ｏ３）二元复合驱油系中的腐蚀形态．应用动电位扫描法和交流阻抗研究了其均匀腐蚀、点蚀和钝化行为，并以 Ｘ 衍射分析腐蚀产物主要成分．结果表明，４５ 碳钢在 Ｈ Ｐ Ａ Ｍ 溶液中属活性溶解过程，在 Ｈ Ｐ Ａ Ｍ ／ Ｎａ２ Ｃ Ｏ３ 复合溶液中随 Ｎａ２ Ｃ Ｏ３ 浓度增加，表面逐渐形成致密α Ｆｅ２ Ｏ３ 氧化膜，腐蚀由活化转入钝化，但低浓度 Ｎａ２ Ｃ Ｏ３

The corrosion behavior of type 45 carbon steel in polymer oil recovering system has been investigated by a simulated experiment set. The uniform corrosion, pitting and passivation of type 45 steel in HPAM and alkaline (Na 2CO 3) mixed flooding medium were studied by potentiodynamic scanning and EIS method. The result showed that type 45 steel showed an active dissolution in HPAM solution. However, it would be changed into passivation if the concentration of Na 2CO 3 increased up to 2.0wt% in HPAM+Na 2CO 3 mixed medium due to forming a compact α\|Fe 2O 3 oxide film on metal surface, but pitting emerged in lower concentration of Na 2CO 3(<0.5wt%).