Key technologies and progress of enhanced gas recovery in water-bearing carbonate gas reservoirs

Global oil and gas consumption continues to rise and new strategies are required to meet the growing demand. Carbonate gas reservoirs are an important natural gas resource that are often accompanied by water intrusion during the development process. The efficient development of such reservoirs has therefore been extensively studied and met with difficulty. This paper summarizes the basic geological and water invasion characteristics of water-bearing carbonate gas reservoirs and correlates the two. A method for identifying water invasion types by production dynamics is introduced. The variation curve of the production water to gas ratio is shown to correspond with the reservoir geological characteristics. Typical development methods and the advantages/disadvantages of different water control techniques are summarized. The findings are used to propose a full-cycle water control plan for water-bearing carbonate gas reservoirs, and the development strategies of "early preparation, early discovery, and early treatment" and "re-analyze, re-assess, and re-adjust" are implemented to organically combine water control, drainage, and water blocking methods. The results provide a reference for formulating efficient and scientific development plans of water-bearing carbonate gas reservoirs. (C) 2022 Sichuan Petroleum Administration. Publishing services by Elsevier B.V. on behalf of KeAi Communication Co. Ltd.