Methane adsorption capacity is an important parameter for coalbed methane (CBM) exploitation and development. Traditional examination methods are mostly time-consuming could not detect the dynamic processes of adsorption. In this study, a modified low-field nuclear magnetic resonance (NMR) method that compensates these shortcomings was used to quantitatively examine seven medium-rank coals. Bas...

Unusually large and locally variable carbon isotope excursions coincident with mass extinctions at the end of the Permian Period (253 Ma) and Guadalupian Epoch (260 Ma) can be attributed to methane outbursts to the atmosphere. Methane has isotopic values (dC) low enough to reduce to feasible amounts the carbon required for isotopic mass balance. The duration of the carbon isotopic excursions an...

The British Columbia Geological Survey Branch and the Geological Survey of Canada have initiated ajoint project to assess the coalbed-methane potential of coal deposits in British Columbia. This project entails participation with private industry to obtain fresh coal samples for desorption from exploration projects throughout the province. Samples are collected from the drill site and undergo a...

One significant factor in the operation of a fluidized bed combustor is the manner in which coal particles disperse and mix with the bed material upon entering the bed. A thermal tracing technique was used to study the mixing characteristics in a 1/4 scale model of a pressurized bubbling fluidized bed combustor. Particles cooled by liquid nitrogen are injected into the bed in the same way that ...

In recent years, coal production and consumption increased dramatically, especially in China. So, more and more attentions have been paid to coal preparation and coal ash utilization with the growing concern about the pollution by fly ash. The unburned carbon in fly ash significantly affects its utilization in many fields, especially in concrete production industry. Technologies such as flotati...

The measurement of wellbore annulus gas-liquid two-phase flow in CBM (coalbed methane) wells is of great significance for reasonably developing gas drainage and extraction processes, estimating CBM output, judging the operating conditions of CBM wells and analyzing stratum conditions. Hence, a specially designed sensor is urgently needed for real-time measurement of gas-liquid two-phase flow in...

Coal is a major energy source, and on the other hand coal is a source of pollution. Some of the important environmental issues related to use of coal in energy production are the release of sulphur dioxide (SO2). SO2 is a precursor to acid rain, responsible for atmospheric pollution and damage to human health. Therefore, investigations and development of technologies promising low SO2 emission ...

As an important component of coal structure, the macropores have a great influence on CBM recovery. In this paper, characteristic two samples collected from 3# seam in south Qinshui Basin, China was analyzed basic mercury intrusion porosimetry, and fully coupled triple-porosity/double permeability mathematical model for recovery established according to physical structure non-Darcy flow methane...

Adsorption and diffusion are the key factors affecting coalbed methane (CBM) accumulation, resource assessment production prediction. To study adsorption mechanism of Fukang low-rank coal at microscopic level, samples were collected, elemental composition, carbon type distribution functional group structure determined by analysis (Ea), Fourier-transform interferometric radiometer (FTIR), X-ray ...