Physical and analytical modelling of permeability damage in bituminous coal caused by fines migration during water production

Experimental results indicate a ∼35% decline in coal permeability during 33 days of water flow. The produced fines are mostly coal and coal-clay mixtures, which is different from the observation of Guo et al. (2015) for the anthracite coal where the majority of fines were clay only. Analytical modelling suggests that the major controlling parameters for fines migration during the flow test are the flow rate, interaction energy and coal characteristics. The analytical model also reveals that most of fines are mobilized in the beginning of the flow test.