Gas emission through coal particles using instantaneous gas diffusion coefficients: experimental and modelling study. (3rd October 2019)

• Record Type: Journal Article
• Authors: Shi, Guangshan; Hao, Tianxuan; Bai, Pengfei; Zhang, Yugui
• Is Part Of: International journal of oil, gas and coal technology. Volume 22:Number 2(2019)
• Page Start: 269
• Page End: 290
• Publication Date: 2019-10-03
• Subjects: coal particles -- methane -- diffusion coefficient -- similarity theory -- Fick's law -- instantaneous diffusion -- diffusion model -- unipore model -- pore structure -- mean free; Petroleum as fuel -- Periodicals; Gas as fuel -- Periodicals; Coal -- Periodicals; Biomass energy -- Periodicals; Hydrogen as fuel -- Periodicals; 662.6
• Languages: English
• ISSNs: 1753-3309

Abstract

Similarity theory and the second law of diffusion were used to develop a diffusion model to accurately characterise the behaviour of gas emissions from coal particles. A method for calculating instantaneous diffusion coefficients, D ( t ), was established. These were incorporated into the diffusion equation and its analytical solution obtained via separation of variables. The results indicated that changes of D ( t ) as a function of time were described by a power function. The model accurately characterises the entire process of gas emission from coal particles and reflects the complexities of pore size. It provides a new calculation method and theoretical reference for determination and prediction of parameters for gas emission from coal seams. [Received: August 10, 2017; Accepted: January 9, 2018]