During the drainage and gas production process of coalbed methane development

due to the pressure drop

the pulverized coal is prone to appear and brought into fracturing sand. At present

the pulverized coal and the deposition of fracturing sand have become the key factors restricting the continuous and stable drainage and production of coalbed methane. As the proportion of pulverized coal pump blockage in southern Yanchuan CBM Field is high

in order to effectively reduce the occurrence of this kind of operation

prolong the maintenance free period of gas wells

ensure the continuity of the production of the gas wells and cut the operation cost

a circulating well flushing device is developed and the supporting process is formulated. After the field tests

it is clear that the automatic circulation well flushing process can effectively reduce the pump inspection times of the gas well

the hollow rod automatic circulation well flushing process can effectively prolong the maintenance-free operating period of the gas well

and the pump down well flushing process can effectively improve the pump efficiency and increase the daily liquid production of the gas wells. The application results show that the CBM circulating well flushing device and supporting process are well applied in the mine

which can effectively improve the liquid flow velocity in the oil pipe

carry the sand and pulverized coal in the oil pipe to the ground

solve the pump sticking

pump plugging and pump leakage

and provide a new idea for on-site control of pulverized coal.