防砂水平井旋转水射流解堵工艺参数优化实验

设计了水平井解堵效果评价地面实验装置,使用实际堵塞筛管进行了水平井旋转水射流解堵实验,研究了解堵效果与解堵液类型、施工排量、移动方式等施工参数间的定性关系,分析了其影响规律,并对解堵施工参数进行了优化。提出了"阶段推进停留"取代以往的"匀速推进"解堵方式,解堵器每次推进1.5~2 m并停留喷射2~4 min可得到较好的解堵效果。在解堵过程中施工排量越大,解堵效果越好,实际施工中解堵排量不低于550~600 L/min为宜;同时,使用复合酸解堵液,可达到更加均匀的解堵效果。通过实验发现,旋转水射流解堵技术更适用于堵塞严重的筛管,堵塞越严重解堵效果反而越好。

Experiment of parameters optimization for plug removal by rotating jet flow in sand-control horizontal wells

A particular experimental device was designed to perform experiments on plug removal by rotating jet flow with actually plugged sand-control screens removed from horizontal wells in the Gudao oilfield. With this experiment, qualitative relationships of plug removal effects with construction parameters, such as plug remover types, pumping rate and moving mode, were examined and their sensitive regularity was analyzed as well. Finally, a reasonable plug removal and its corresponding parameters were recommended by optimizing construction parameters of plug removal, and this method involved a fashion of "intermittent moving and staying" instead of the previous one of "uniform-velocity moving". An optimal distance for every advance is 1.5~2 m with staying time for 2~4 min, which can produce a better plug removal effect. During plug removal, the higher the pumping rate, the better the plug removal effect can be gained, thereby a real pumping rate should not be less than 550~600 L/min. In addition, the use of a compound-acid plug remover could gain a more even effect of plug removal. The comparison experiment indicated that compound acid tends to remove screen plug more efficiently than clean-water fluid and the plug removal effect of severely plugged screens is better than that of slightly plugged screens. So, the technique of plug removal by rotating jet flow should be applied preferentially to the severely plugged sand control horizontal wells.