新场气田沙溪庙组气藏JS21气层水平井开发效果评价

通过对新场气田上沙溪庙组气藏JS12致密砂岩气层水平井加砂压裂改造后气井的天然气测试产量、单井产气量、单位压降采出天然气量、气井动态储量等气层动态指标与同层的直井或定向井进行对比分析认为,水平井加砂压裂后测试产量较高、稳定产量是直井或定向井的2.45倍、单位压降的采气量明显高于直井或定向井、单井控制的动态储量是直井或定向井的3.6倍,水平井开发效果明显优于直井或定向井,说明水平井加砂压裂改造后达到了最大限度增大致密砂岩储层泄气面积的目的。水平井压裂井段增长、压裂规模增大、单井产量增加的同时,产水量也相应增加,同一区域水平井的产水量是直井或定向井的2～80倍,水气比是直井或定向井的2～5倍;水平井排水采气效果较差,受井筒条件的影响,目前仍缺乏有效的排水采气工艺技术,有待今后探索试验。

EVALUATION OF DEVELOPMENT EFFECT OF HORIZONTAL WELLS IN SHAXIMIAO JS21 RESERVOIR OF XINCHANG GAS FIELD

Comparing dynamic index of JS21 gas reservoir such as testing production,gas production rate of single-well,gas production of unit pressure drop,dynamic reserves etc.with horizontal wells and straight wells of same position,horizontal wells had a higher test production rate after fracturing,stable rate was 2.45times of straight or directional wells’,gas production of unit pressure drop was obviously higher than straight or directional wells,controlled dynamic reserves of single well was 3.6 times of straight or directional wells,the developing effect of horizontal wells was obviously better than straight or directional wells.With the growth of fracturing section of horizontal wells,augmentation of fracturing scale and incremental single-well production rate,water yield was growing as well,and horizontal wells’ water yield in the same region was 2～80 times of straight or directional wells’,WGR was their 2～5 times.Drainage gas recovery effects of horizontal well were still poor.With the influence of well bore condition,it still lacked effective technology of drainage gas recovery currently and need investigate from now on.