直井与水平井的产能对比

摘要

Exploitation of reservoirs can use either vertical wells or horizontal wells.Wells can be either fractured or unfractured.In well stimulation selection of field practice,the stimulation proficiency is usually taken into ac-count at first besides of stimulation cost.The stimulation proficiencies of vertical wells and horizontal wells were studied under two circumstances of wells being fractured and not fractured.The effects of pay thickness,drain-age area,fracture number,rock permeability and fluid viscosity to stimulation proficiency were also studied sep-arately.The study shows that the stimulation proficiency of unfractured horizontal wells is not so good as vertical fractured wells. The thick oil layer is suitable for being exploited by vertical wells,while the thin oil layer is more suitable for using horizontal wells than vertical wells. The larger drainage area of wells cannot increase their stimulation proficiency largely,and can prolong the production time of wells.The fracture number of wells can increase their stimulation proficiency very effectively.The volumetric fracturing or multi-stage fracturing is the most effective stimulation method of horizontal wells.Horizontal wells cannot demonstrate higher stimulation proficiency without fracturing.The middle and high permeability reservoirs can take any types of well for exploi-tation,but the low permeability reservoirs must use fractured horizontal wells.The middle and low viscosity oil reservoirs can take any types of well for exploitation,but the high viscosity or heavy oil reservoirs must be developed by the aid of thermal recovery method.%油藏开采可以选用直井,也可以选用水平井,可以对油井进行压裂,也可以不进行压裂.矿场上选用何种增产措施,除了要考虑成本之外,还要考虑措施的增产效果.分油井压裂与不压裂2种情形,对比了直井与水平井的产能,同时通过计算示例分析了泄油面积、储集层厚度、压裂裂缝条数、储集层渗透率和原油黏度对增产效果的影响.研究表明:普通水平井的增产效果不如压裂直井;厚油层适合采用直井开发,薄油层适合采用水平井开发;增大泄油面积不能有效提高油井产能,但能延长稳产期;增加压裂裂缝条数能显著提高水平井产能,体积压裂及多级压裂均是水平井的有效增产途径;未压裂水平井的增产效果十分有限;中高渗透油藏可以采用任意油井开发,而低渗透油藏则必须采用压裂水平井开发;中低黏度油藏可以采用任意油井开发,而高黏度油藏或稠油油藏则必须借助于热力采油.研究结果可为矿场上选择油井类型及增产措施提供参考.