Characterization method of closed pores and connectivity of coal measure composite reservoirs

US11781962B2 · kind B2 · utility

Assignee

• China University of Mining and Technology · CN

Inventors

• Yang Wang · Nanhu, CN
• Jie Xiang · San Jose, US
• Shangbin Chen · Xuzhou, CN
• Tong Zhang · Palo Alto, US
• Qingshun Cao · Xuzhou, CN

Key dates

• Filing date: Mar 22, 2023
• Grant date: Oct 10, 2023
• Expiry date: Mar 22, 2043

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02A90/30
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Disclosed is a characterization method of closed pores and connectivity of coal measure composite reservoirs, including collecting samples of coal seams and shales reservoirs, carrying out low-field NMR experiments and NMR freeze-thaw experiments on plunger samples and crushed samples with different particle sizes to obtain cumulative pore volume distribution and differential pore size distribution of the crushed samples, comparing crushed samples with plunger samples for optimal crushed particle sizes, and preliminarily determining a distribution range of closed pores; carrying out SAXS experiments on crushed samples to obtain size distribution and volume of total pores of 1-100 nanometers; calculating pore volume of total pores and closed pore volume in composite reservoirs by low-field NMR experiments results; carrying out non-steady overburden permeability experiments and variable factors on plunger samples of coal seams, shales and tight sandstone to characterize the connectivity under influence of pores development and lithologic combinations.