Transport mechanism of desorbed gas in coalbed methane reservoirs

Enhanced Gas Drainage from Undersaturated Coalbed Methane Reservoirs

Traditional methods of coal seam gas drainage rely on the use of reservoir pressure reduction to promote gas desorption from the coal matrix. Studies in coal mining gas drainage operations, particularly in coal seams that are deeply undersaturated and have low permeability, found the rate of reservoir pressure reduction was prohibitively slow. In such conditions, lengthy production delays have ...

Permeability Variation Models for Unsaturated Coalbed Methane Reservoirs

A large number of models have been established to describe permeability variation with the depletion of reservoir pressure to date. However, no attempt has been made to draw enough attention to the difference in the effect of various factors on permeability variation in different production stages of unsaturated CoalBed Methane (CBM) reservoirs. This paper summarizes the existing and common per...

Well Evaluation for Coalbed Methane

Coalbed Methane Canister Desorption Techniques

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...

The Composition of Coalbed Gas

TABLES ..................................................... . 1 Coalbeds sampled ........................ . . 2 Composition of gas from Pocahontas No 3 c o a l ...... . 3 . Hydrocarbons from Pocahontas No 3 c o a l ........................ . . 4 Composition of gas from P i t t sbu rgh coa l ............................ .......................... . 5 Composition of gas from Ki t tanning coalbed...