中原油田文72块油井防垢技术研究

Technical Research of Scaling in Oil Wells at Wen-72 Block Reservoir in Zhongyuan Oilfield

使用预测软件OFISTP3.0预测,中原油田文72块3口生产井近井地带存在碳酸钙和硫酸钙结垢,与现场情况基本一致。通过岩心结垢流动实验,在储层岩心中依次注入不含结垢离子模拟注入水、模拟地层水及分别加入20、10 mg/L防垢剂SA1320C的模拟地层水,得到的渗透率保留率与注入水量关系曲线反映了CaCO3垢在岩心中的沉积和注入防垢剂的防垢效果,该防垢剂在加量10 mg/L时即具有良好的防垢作用。防垢剂与抑盐剂复配实验结果表明,二者的配伍性较差,建议采用防垢剂井下挤注,抑盐剂环空投加的方法。

It is shown by using predicting software OFISTP3.0 that the CaCO3 and CaSO4scale crea-tion exist in the near bore zone of three oil wells at Wen-72 block and this result is basically in ac-cordance with field observations. In reservoir core flow experiments, a non-scaling simulation injec-tion water, the simulation formation water and the simulation formation water with scale inhibitor（SI） SA1320C added at dosage 20 and 10 mg/L, respectively, are injected successively and thecore permeability retention injected water volume curve demonstrates the formation of CaCO3 scale inthe core and the function of the SI with minimum SI dosage being of 10 mg/L. The combination ex-periments of scale inhibitor and salt inhibitor indicate the short of compatibility of medicines, so it isproposed to pack the scale inhibitor in downhole and put in salt inhibitor in annulus space.