New method of gas recovery by water drainage measure optimization for water bearing gas wells in Su-59 block of Sulige Gas Field

The main gas formations of Su-59 block have the characteristics of isolated distribution of gas-bearing sandstones, low gas saturation, low formation pressure coefficient and great difference of gas well productivity, which brings great difficulties for the optimization of measures of gas recovery by water drainage for water bearing gas wells. Through comparative analysis, the Arps gas production decline analysis model was chosen to analyze most of the gas wells in Su-59 block, and the QGD, integrated gas well production capacity index, was put forward, which reflects the single well controlled gas-bearing area, formation pressure and reservoir properties. According to the QGD, formation pressure and the statistical analysis of implementing wells, a new method of determining implementing measures for Su-59 block is formed. The new method concerns not only the effect of gas production and water production to the measures of drainage gas recovery, but also the effect of single well controlled gas-bearing area, formation pressure and reservoir properties. It will be great significance for the gas wells in Su-59 block or similar blocks to determine measures of gas recovery by water drainage with the new method.