齐成伟带纵公式在带状高含硫气藏中的推广

Generalization of Revised Qi Chengwei′s Formula for Vertical Double-branch Horizontal Wells in the Ribbon-shaped Sour Gas Reservoirs

齐成伟带纵公式不适用于带状高含硫气藏,根据气相渗流与液相渗流的相似原理和Roberts气体相对渗透率与含硫饱和度的关系,将齐成伟带纵公式的适用条件推广为高含硫气藏,推导出了带状高含硫气藏中纵向双分支水平井的拟三维产能预测公式,即齐成伟带纵公式的高含硫气藏推广公式。根据齐成伟带纵公式的高含硫气藏推广公式,分析了硫沉积量、渗透率各向异性系数、带状气藏长度、生产段井筒位置和生产段长度对产能的影响。分析结果表明:产能随着含硫饱和度或渗透率各向异性系数的增大而减小;相同井境下,含硫饱和度对产能的影响要明显大于渗透率各向异性系数;产能随着带状气藏长度的增大而减小;产能随着生产段井筒位置的增大先增大,后减小,且当生产段井筒处于气藏中央高度时,产能最大;产能随着生产段长度的增大而增大。

According to the similarity principle between gas seepage and liquid seepage and the relationship between gas relative permeability and sulfur saturation summed up by Roberts ,the famous Qi Chengwei＇s for- mula is successfully generalized to the pseudo three-dimensional productivity one for the vertical double- branch horizontal wells in the ribbon-shaped sour gas reservoirs.That is the generalized Qi Chengwei＇s pro- ductivity formula for the vertical double-branch horizontal wells in the sour gas reservoirs.Based on the gen- eralized formula,the impact of deposited sulfur content,permeability anisotropy coefficient,length of ribbon- shaped gas reservoir ,wellbore position of production section ,length of production section on the productivity is analyzed.The results show that：the productivity will decrease along with the increase of the sulfur saturation and permeability anisotropy coefficient,but the effect of the sulfur saturation on the productivity is greater than that of the permeability anisotropy coefficient at the same well situation ;and it will decrease along with the increase of the length of the ribbon-shaped along with the increase of the wellbore position the wellbore of the production section is at the gas reservoir.The productivity will increase first then decrease of the production section, and it will be the maximum when middle height of the gas reservoirs.It will increase along with the increase of the length of production section also