延长油田空气泡沫驱腐蚀防护研究

Study on Corrosion Protection of Air Foam Flooding in Yanchang Oilfield

延长油田空气泡沫驱腐蚀问题严重,针对这一问题做了空气泡沫驱注采管线腐蚀防护研究,考察了缓蚀剂、杀菌剂、牺牲阳极材料和氧浓度对挂片腐蚀的影响。实验结果表明:高效缓蚀剂YC607和9#现场用缓蚀剂能降低腐蚀速率56.3%,缓蚀效果良好;与现场使用的杀菌剂相比,癸甲溴胺缓蚀效果最佳,腐蚀速率为0.370 5 mm/a;相比于镁合金和铝合金,牺牲阳极材料以锌合金的防腐效果最好,适宜用于保护阴极套管;氧含量过高是空气泡沫驱腐蚀严重的主要原因之一,因此将氧含量控制在4%的浓度范围内,可有效减缓腐蚀的程度和速度,氮气泡沫驱可替代空气泡沫驱达到防腐的目的。

The corrosion in air-foam flooding of Yanchang oilfield is very serious,in order to solve this problem,the research on corrosion and protection was carried out in the pipeline of air-foam flooding.The effect of corrosion inhibitors,fungicides,sacrificial anode materials and oxygen concentration on the corrosion of the rotary steel was investigated.The results showed that the corrosion rate was reduced by 56.3%with high efficiency corrosion inhibitor YC607and 9#in the field application.Decamethylamine as a fungicide showed better inhibition effect than the one applied in Ganguyi oilfield,it reduced the corrosion rate to 0.3705mm/a.Among the magnesium alloy,aluminum alloy,and zinc alloy,the last one had the best antieorrosion effect as the sacrificial anode material,which is suitable for protecting cathode casing.High oxygen content of air foam flooding was one of the leading causes of severe corrosion, ,if the oxygen content was under 4%,it could effectively slow down the rate of corrosion,and nitrogen-foam flooding could also replace air-foam flooding to achieve the better effect on corrosion prevention.