Investigation of pressure propagation in coal reservoirs and formulation of the drainage system for CBM vertical wells

Study on the Permeability Enhancement of Propped Fractures under the Action of a Coal Fine Plugging Removal Agent

“…China is the third largest coalbed methane (CBM) reservoir in the world with the rich CBM resources. − China’s CBM industry was severely impeded by a large number of unproductive and inefficient wells, in which the accumulation of coal fine retention in propped fractures significantly restricted the gas production. , At present, it is difficult for fresh water to fully and effectively eliminate the blocked coal fines in propped fractures, with the unfavorable effects of coal fine blocking . Consequently, it is essential to investigate and create a coal fine plugging removal agent with excellent dispersion properties and powerful powder-carrying capacity so that the coal fines can steadily suspend in liquid and facilitate the release of the retained coal fines in propped fractures. − The research would accomplish the unblocking of the propped fractures and the enhancement of the permeability, which provides theoretical backing for the dependable and effective drainage of methane–water–coal fines. − …”

“…China is the third largest coalbed methane (CBM) reservoir in the world with the rich CBM resources. 1 − 3 China’s CBM industry was severely impeded by a large number of unproductive and inefficient wells, in which the accumulation of coal fine retention in propped fractures significantly restricted the gas production. 4 , 5 At present, it is difficult for fresh water to fully and effectively eliminate the blocked coal fines in propped fractures, with the unfavorable effects of coal fine blocking.…”