油田注水结垢影响因素研究

Influencing Factors on Oilfield Injection Scaling

模拟某油田注水环境,通过测定模拟水样失钙率和SEM观察垢物晶型,分析常压静态和高温、高压动态条件下油田结垢的影响因素.试验结果表明:在常压静态条件下,随着矿化度的提高,水样中NaCl浓度提高,失钙率先提高后下降;在高温、高压动态条件下,随着温度的升高和pH值的增加,模拟水样的失钙率提高,油田结垢趋势增强;随着压力、流速的增加,模拟水样的失钙率下降,油田结垢趋势减弱.SEM观察结果表明:某油田结垢的主要原因是温度变化和注水与地层水混合后pH值的变化,阻垢措施应为:调节注水的酸碱度和选用耐温性好的阻垢剂.

Influencing factors on oilfleld scaling are discussed under static atmospheric pressure and dynamic high temperature and pressure conditions, by simulating an oilfield injection environment, measuring the simulation water calcium loss rate and observing scale crystal from SEM. Results are as the followings： in high temperature and pressure and dynamic state, NaCl concentrations increases and the calcium loss rate increases first, then decreases with the rise of mineralization; in high temperature and pressure and dynamic state, calcium loss rate increases and scaling tendency enhanced with the rise of temperature and pH value; calcium loss rate and Scaling tendency decrease with the rise of pressure and flow velocity. SEM results show that the main reason for the oilfield scaling is temperature change and pH value change caused by injection water and formation water mixture And the way to inhibit scaling is adjusting acidity-alkalinity of injection water and selecting good temperature resistance scale inhibitor.