Research on Productivity Management of Gas Wells in Low Permeability Carbonate Reservoir

Abstract

Productivity management is the core content of gas field development, which focuses on the evaluation of gas well production capacity and how to use gas well productivity to guide gas well working schedule. According to the differences of production performance and test data in the early, middle and late development stage, this paper put forwards the key technical difficulties of productivity evaluation when to face features of low permeability, limited productivity test and large number of wells in low permeability carbonate gas reservoirs. Furthermore, on the basis of adaptability analysis of the existing productivity evaluation methods, technical approach of productivity management is proposed targeted at the open flow potential verification in the early stage, the productivity equation coefficient modification with changing filed pressure in the middle term and the production decline law determination in the later stage by using regular production data. The research results are applied to M gas field in Ordos Basin and convey that gas wells productivity realize continuous tracking and evaluation without shut in test. Besides, the unbalanced exploitation degree of M gas field is effectively alleviated and stable gas supply in gas area is guaranteed with the formulation of gas well production schedule and adjustment of production measures. The research also have guiding significance for the development and practice of similar gas reservoirs in China.KeywordsLow permeability carbonate gas reservoirProductivity evaluation methodsReasonable working scheduleRegular production dataVariable filed pressureProduction decline analysis