GEOCHEMICAL RESEARCH OF GAS PRODUCTION FROM LOW-PERMEABLE GAS DEPOSITS

摘要

1. A method for estimating the gas recovery coefficient for a volume drained by at least one productive well passing through a dense gas or methane reservoir in a coal seam, comprising the steps in which:! (a) calibrate changes in the isotopic composition of at least one component of the gas produced from a gas well with an increase in gas recovery coefficient; ! (b) receive a sample of produced gas from a productive gas well and analyze this sample to determine the isotopic composition of the component of the produced gas; ! (c) use the calibration obtained in step (a) and the isotopic composition determined in step (b) to estimate the gas recovery coefficient for the volume drained by the gas well; ! (d) use the gas recovery coefficient estimate determined in step (c) and the total volume of gas produced from the gas well to determine the volume drained by the gas well, and! (e) optionally repeating steps (b) to (d) to determine any increase in time of the gas recovery coefficient for the volume drained by the gas well and any increase in time of the volume drained by the gas well. ! 2. The method according to claim 1, in which several existing gas wells penetrate into the reservoir and which use an estimate of the gas recovery coefficient for the volume drained by each existing gas well and an estimate of the volume drained by each existing gas well to determine the spatial distribution of the drained volume of the reservoir and / or any changes in the coefficient of gas recovery in the drained volume of the reservoir, and thereby identification �