复合堵漏中平衡区域及其在新型堵漏仪中的应用

Balance area of compound lost circulation control and its application in novel lost circulation simulator

复合堵漏剂进入漏层后,堵漏材料会在漏层中散布,各种堵漏材料在某区域所占比例基本平衡。针对此问题,提出了存在平衡区域的概念。研制了新型堵漏仪,该堵漏仪能充分模拟漏失地层和堵漏过程,实验后还可以剖开实验岩心观察堵漏材料在岩心中的分布滞留状况和平衡区域的位置,从而为堵漏配方做进一步调整提供依据。多次实验发现,当堵漏效果好时平衡区域向岩心入口端移动,效果不好时则向岩心出口端移动,甚至不能形成平衡区域。新型堵漏仪实验结果重复性好,所形成的配方可直接应用于现场堵漏作业。现场应用表明,该应用技术在防漏堵漏作业中取得了很好的效果。

The compound plugging material is broadly distributed in the leakage formation after compound plugging agent is injected into the leakage formation. The proportion of various plugging material in some area is balanceable relatively. So, there is a balance area. The concept of balance area is useful for lost circulation control. A novel lost circulation simulator for simulating leakage formation and lost circulation control procedure perfectly was developed. The distribution and occlusion status of plugging material and the position of balance area were experimented on core in laboratory and could be observed from the experimented core cutting. The lost circulation control formula can be modulated till the experiment successes. The experimental result showed that the balance area would move towards the entry side of core, if the effect of lost circulation control was good. Otherwise, it will move towards the outlet of core, even no balance area appeared in the core. The experiment of new lost circulation simulator has a good repeatability. The formula acquired by experiment was applied directly to the lost circulation control in field. The result showed that this technology has been successfully applied in the procedure for lost circulation prevention and control.