Constant-volume closed gas reservoir gas well production declining rate prediction method

• Main Authors: SHI LIYU, QIAO XIANGYANG, XIN CUIPING, WANG KAI, SONG JIAXUAN, BAI HUIFANG, DU YONGHUI, XU WEI
• Format: Patent
• Language: Chinese; English
• Published: 07.07.2023
• Subjects: CALCULATING; COMPUTING; COUNTING; DATA PROCESSING SYSTEMS OR METHODS, SPECIALLY ADAPTED FORADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL, SUPERVISORYOR FORECASTING PURPOSES; EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; ELECTRIC DIGITAL DATA PROCESSING; FIXED CONSTRUCTIONS; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; PHYSICS; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE,COMMERCIAL, FINANCIAL, MANAGERIAL, SUPERVISORY OR FORECASTINGPURPOSES, NOT OTHERWISE PROVIDED FOR

The invention belongs to the technical field of gas reservoir engineering, and particularly relates to a constant-volume closed gas reservoir gas well production declining rate prediction method, which comprises the following steps: taking D (n) of an initial declining rate value, and obtaining annual gas production Gp1 (n) of the first year after declining; the formation pressure initial value PR1 (m-1) (n) at the end of the first year after gas well decline is taken, it is required that PR1 (m-1) (n) is smaller than PRi, the corresponding deviation coefficient initial value ZR1m-1 (n) is obtained, and the formation pressure PR1 (m) (n) in one year after decline is obtained; calculating the daily gas production q1 (n) at the end of the first year after decline; and calculating the gas well declining rate D '(n). According to the method, by adopting the ratio of the yields at different moments, the influence of parameters is eliminated, and the calculation precision is greatly improved. 本发明属于气藏工程技术领域，具体涉及一种定容