Petroleum Reservoir Evaluation and Development ›› 2021, Vol. 11 ›› Issue (5): 724-729.doi: 10.13809/j.cnki.cn32-1825/te.2021.05.009

• Offshore Oil andGas Exploration and Development • Previous Articles     Next Articles

A productivity evaluation method of gas wells in condensate gas reservoirs with low permeability

TAN Xianhong(),LIANG Bin,WANG Shuai,TIAN Bo,PENG Shiqiang,LI Nan,XIA Yang   

  1. CNOOC Research Institute, Beijing 100028, China
  • Received:2021-04-14 Online:2021-10-26 Published:2021-10-12

Abstract:

When the conventional binomial productivity equation is used to analyze the deliverability of the gas wells in a low permeability thick layer condensate gas reservoir with high condensate content in Bohai Sea, the negative deliverability equation coefficient B can be obtained, which is still negative after pressure correction. Therefore, this equation is not suitable for the gas well productivity analysis. In order to obtain the reasonable productivity equation of the gas well, the following measures are taken. Firstly, the judgment criterion of high-speed non Darcy seepage and the theoretical calculation of productivity equation coefficient B are used to confirm that the high-speed non Darcy of the gas well is negligible, and the formation pressure and bottom hole flow pressure also need to be corrected. Then, the modified productivity equation is obtained without high-speed non Darcy productivity equation. Finally, the exponential productivity equation is used for verification, and the calculated QAOF(open flow, the same below) is basically consistent with the QAOF the modified productivity equation. When this new method is applied to the actual gas wells in low permeability condensate gas fields, a reasonable gas well productivity equation can be obtained, which shows the effectiveness of the modified productivity equation.

Key words: low permeability, condensate gas reservoir, correction, high speed non-Darcy, deliverability equation

CLC Number: 

  • TE37