聚合物驱抽油井缓蚀剂的研制

Research of Corrosion Inhibitors for Polymer Flooding Pumping Wells

孤东油田聚合物驱抽油井腐蚀情况比水驱严重,通过失重试验考察了聚合物驱采出液中聚合物浓度、含砂量、细菌含量等因素对A3钢油井管杆腐蚀速率的影响,对聚合物驱抽油井的腐蚀特点进行了分析。结果显示,聚合物驱采出液中含有的残余聚合物有一定的缓蚀作用,但影响程度不大;残余聚合物使得采出液黏度增加,携带悬浮物的能力增强造成磨损腐蚀严重以及加剧细菌繁殖使得细菌腐蚀加重,是导致聚合物驱抽油井腐蚀程度较水驱严重的主要原因。室内合成了一种咪唑啉类缓蚀剂,用红外光谱对其进行了表征,确定了其与葡萄糖酸钠的复配比例,并优选出聚合物降解剂和高效杀菌剂与之复配,当复合缓蚀剂质量浓度在80mg/L左右时,缓蚀率超过85%。

Pumping wells adopting polymer flooding face more serious corrosion problems than those using water flooding in Gudong oilfield. Thus the features of corrosion of the pumping wells associated with polymer flooding were analyzed,and the effects of polymer concentration,amount of sand and amount of bacterial in the fluid produced along with polymer flooding on corrosion rate were investigated by making use of weight-loss tests. Results indicate that residual polymers in the fluid produced along with polymer flooding show limited inhibition action,but lead to increased viscosity and capability to carry floating substances of the fluid,causing serious wear-induced corrosion and bacterial-induced corrosion of the pumping wells. Further,an imidazoline corrosion inhibitor was synthesized,and its chemical feature was analyzed by means of infrared spectrometry. Moreover,the inhibitor was combined with sodium gluconate,polymer degradation agent and highly active fungicide,and the inhibition performance of the combined inhibitor was evaluated. An inhibiting efficiency of over 85% was obtained when the inhibitor was introduced at a dosage of 80 mg/L.