强碱三元复合驱颗粒调剖剂强度和弹性评价方法

随着油田开采进入中后期,尤其是近井地带多次重复调堵后,大量注入体系沿高渗透层或特高渗透层做无效和低效循环,降低了驱替效果。为了保证颗粒调剖剂的质量,增强其稳定性,提高驱替效果,结合现场实际应用情况,开展了强碱三元复合驱颗粒调剖剂强度和弹性评价方法研究。基于调剖剂颗粒在地层中运移时产生的挤压、剪切、变形等力学行为,确定了三元复合驱颗粒调剖剂强度表征方法;测定了8种不同类型调剖剂颗粒在不同膨胀时间条件下通过孔板时的突破压力和不同压力条件下的回弹系数。结果表明:调剖剂颗粒放置时间越长,其强度越低;对于同种类型不同粒径的颗粒调剖剂,粒径越大,其过孔突破压力越大;8种样品64样次测定结果中回弹系数大于20%的样品次数达到70%以上。通过研究发现同类产品的颗粒回弹系数和过孔突破压力具有负相关性,形成了综合考虑回弹系数和过孔板突破压力2个指标的颗粒调剖剂性能评价方法。

Evaluating method of the strength and elasticity of the particle profile-controlling agent for strong-alkali ASP flooding

With the development of the oilfield in the middle and late periods, especially after repeated plugging and profile control near the wellbore, a large number of the injecting systems circulate ineffectively and inefficiently along the high-permeability layer or ultra-high-permeability layer, thus the displaced effects have been reduced. In order to ensure the quality, strengthen the stability of the particle profile-controlling agent and improve the displaced effects, integrated with the actual application conditions in the field, the evaluating method of the strength and elasticity of the particle profile-controlling agent for strong alkali ASP flooding was carried out. Based on the mechanical behaviors of squeezing, shearing and deformation and so forth caused by the particle migration in the formation, the strength characterizing method of the particle profile-controlling agent for the ASP flooding was determined;the breakthrough pressures were measured for eight different kinds of the profile-controlling agent particles passing through the orifice plate under different expansion time, and so did the rebound coefficient under the conditions of different pressures. The results show that the strength of the profile-controlling agent particles decreased with the prolongation of the storage time;for the profile-controlling agents of the same type with different particle sizes, the larger the particle size is, the higher the through-hole breakthrough pressure will be;the number of the samples which resilience coefficients are more than 20% have reached 70% for eight samples tested 64 times. The study finds out that there is the negative correlation between the resilience coefficient and the breakthrough pressure of the same kind of products, thus the performance evaluating method of the particle profile-controlling agent has established considering the following two factors: both the resilience coefficient and the breakthrough pressure through the plate.