Changes

# Declining production phase, and during the declining production phase, the amount methane produced will decrease until uneconomical stage of production.

# Declining production phase, and during the declining production phase, the amount methane produced will decrease until uneconomical stage of production.

[[File:UGM_Vibro_Fig_3.png|thumb|300 px|{{figure number|3}}CBM production gas concept, showing dewatering phase, stable production phase, and decline phase(Rogers, 1994).\]

[[File:UGM_Vibro_Fig_3.png|thumb|300 px|{{figure number|3}}CBM production gas concept, showing dewatering phase, stable production phase, and decline phase(Rogers, 1994).\]]

The previous study indicate that vibration stimulation can change the coal properties, such as porosity and absolute permeability (kabs). Permeability is the main parameter of CBM reservoir in determining response of reservoir – reservoircoal – seam. The high value of permeability will increase the gas production rate related to the increase of gas desorption process speed.<ref name=Ariadji_et_al />

The previous study indicate that vibration stimulation can change the coal properties, such as porosity and absolute permeability (kabs). Permeability is the main parameter of CBM reservoir in determining response of reservoir – reservoircoal – seam. The high value of permeability will increase the gas production rate related to the increase of gas desorption process speed.<ref name=Ariadji_et_al />