Case study of estimating gas loss from a producing well blowout

The purpose of this study is to estimate gas loss from a production blowout of well K-140 in a gas field in Taiwan. Two approaches can be successfully used to estimate gas loss: (1) analysis of the p/z plot, based on the gas material balance equation, and (2) study of pressure history matching of reservoir simulation. In the analysis of the p/z plot, the gas loss from well K-140 is estimated by analyzing the differences between the pressure prior and subsequent to blowout in the p/z plot. In the reservoir simulation study, two stages of pressure history matching are separately conducted using pressure data before and after the blowout. The first stage history match is for tuning the numerical model; the second stage history match is for estimating gas loss from the production blowout of well K-140. The gas loss estimated from the history match is 1.45 ∗ 1010 SCF (4.11 ∗ 108 SCM) which is very close to the 1.358 ∗ 1010 SCF (3.85 ∗ 108 SCM) estimated from analysis of the p/z plot.