Moisture-Induced Swelling of Coal

A new laboratory method for accurate measurement of the methane diffusion coefficient and its influencing factors in the coal matrix

“…The reasons for these observations are that the polar functional groups on the coal surface have surface activities, and the wettability to water is higher. When the water in the coal matrix increases, the coal rock expands [43] and then the adsorption effects of methane molecules on the coal matrix are reduced substantially, which makes it hard for the methane molecule to be absorbed and forms a large concentration gradient. Therefore, the methane diffusion coefficients of wet samples are small and the diffusion rate is slow, while the diffusion coefficients of dry samples are high and the diffusion rate is fast.…”

Optimizing enhanced coalbed methane recovery for unhindered production and CO2 injectivity

“…The presence of moisture in fractures will inhibit the flow of gas by occluding pore-space. Additionally, the moisture in the micro-and mesopores will influence flow tortuosity and out compete for sorption sites (Day et al, 2008;Fry et al, 2009). The moisture loading in coal swells the matrix to a degree (Fry et al, 2009;Robertson, 2005).…”

A review on transport of coal seam gas and its impact on coalbed methane recovery

“…Fry etc. [72]. investigated the moisture-swelling properties of coals 15 coals of various ranks (sub-bituminous and bituminous) at 22°C and atmospheric pressure.…”

“…In: Proceedings of the Asia Pacific Coalbed Methane Symposium, Brisbane, Australia. 2008, Paper 007literature[23,25,30,31,36,69,[71][72][73][74]. Several representative studies are worth highlighting as follows.…”