CO_2 STORAGE POTENTIAL AND ENHANCED COAL SEAM METHANE RECOVERY WITH RESPECT TO MIXED GAS CONDITIONS FOR EASTERN AUSTRALIAN COALS

摘要

Australian coal seams generally contain high volumes of gas; for example at depths of less than 150 m, gas contents range up to ～ 5 m~3/t whereas at 700 m, contents are up to ～ 25 m~3/t. Significant coal seam gas production in Australia started in 1995 and this has increased substantially in recent times, in particular in Queensland and New South Wales, with advances in drilling and well completion technologies. In Queensland alone currently about 50-60 PJ, or ～ 40% of the state's gas consumption, is supplied from coal seam methane.