凝析气井油管优化机理模拟研究

柯克亚凝析气田是以中孔小喉道、低渗储层为主的凝析气田，地层流体以凝析气为主，原始凝析油含量在300．600，0之间，且为饱和凝析气藏，在地层压力稍一下降，地层中马上出现大量反凝析液，这要求凝析气井的油管选择不能与干气井、湿气井类同，必须考虑井筒携液的问题，而气田油气井油管尺寸的选择是根据试采期油气藏产能进行编制开发方案时所确定；随着开发时间的延续，油气藏逐渐进入产能递减期，地层压力大幅度下降，井筒的摩阻损失降低、滑脱效应增大，井筒、井底积液情况屡屡发生，油气产能急剧下降，目前采用的油管尺寸显然已不能达到有效携液的目的；为了提高油气产能，通过不同油管粗糙度、流体组分含量、不同井口压力条件、不同油管尺寸对井筒压力损失及合理产气量的影响进行油管优化机理模拟研究，最终确定油管尺寸与油气举升效率、产量间的关系，并在气田成功措施作业2井次，不仅解决了气体滑脱、并底积液的现象．还提高了油气产能。

MECHANISM AND NUMERICAL SIMULATION STUDY ON OIL PIPELINES OPTIMIZATION OF CONDENSATE GAS WELL

Kekeya condensate gas field in Xinjiang was a gas field of middle porosity,slim throat,low permeability of sandstones.Its fluids were condensate gas,original condensate quantity was 300-600 g/m~3.They were saturate condensate gas reservoirs.With the formation pressure decreased,the retrograde condensation was becoming serious.According to the special condition,choice of the oil pipelines was totally different from that of off-gas wells and wet gas wells.The questions of liquid carrying in Vertical Wellbores must be taken into account.Choice of oil pipleline size of oil&gas wells were determined in terms of the early development scenarios when the gas field was in very early period of exploitation.As time passed,the reservoirs went into the period of production decline;the formation pressure decreased greatly;oil pipeline resistance loss declined;slippage effects increased and gas wells with standing liquid were developed.Oil pipleline size of gas wells were not consistent with the capacity of liquid carrying.For improving production capacity,mechanism and numerical simulation study of oil pipelines optimization was carried out.The decisive factors,such as oil pipeline roughness,the quantity of fluid components,the wellhead pressure,oil pipeline size,were analyzed.The relation between oil pipeline size and efficiency of oil&gas lift and the relation between oil pipline and oil,production were determined.The results were applied to two operation wells successfully,their production capacity was improved.