A system comprising conveyance means for conveying a container (F) to a purge position and comprising a purge device (4; 4B) for purging the container (F) being positioned in the purge position, wherein the container (F) has a gas introduction port on a bottom surface (Fb) thereof and the purge device (4; 4B) comprises: a purge nozzle which is able to blow a purge gas (G1) and is configured to be connected with the gas introduction port of the container (F) when the container (F) is positioned in the purge position; and a purge controller which is configured to control the purge nozzle to blow the purge gas (G1) in a cleaning state of the purge device (4; 4B), when the purge nozzle is not connected with the gas introduction port , and is configured to control the purge nozzle to blow the purge gas (G1) in a purging state of the purge device (4; 4B), when the purge nozzle is connected with the gas introduction port , such that the purge gas (G1) is supplied to an inside (Fa) of the container (F) being positioned in the purge position; wherein the purge controller is configured to control the purge nozzle such that the blowing of the purge gas (G1) in the cleaning state is effected when the bottom surface (Fb) of the container (F) to be purged and the purge nozzle face each other and a gap (GA) between the bottom surface (Fb) of the container (F) and a top surface of the purge nozzle is such that the purge gas (G1) blown through the purge nozzle reaches the bottom surface (Fb) of the container (F), with the purge nozzle not yet being connected with the gas introduction port , and that the blowing of the purge gas (G1) in the cleaning state starts after that the conveyance of the container (F) by the conveyance means to the purge position has started. a purge nozzle which is able to blow a purge gas (G1) and is configured to be connected with the gas introduction port of the container (F) when the container (F) is positioned in the purge position; and a purge controller which is configured to control the purge nozzle to blow the purge gas (G1) in a cleaning state of the purge device (4; 4B), when the purge nozzle is not connected with the gas introduction port , and is configured to control the purge nozzle to blow the purge gas (G1) in a purging state of the purge device (4; 4B), when the purge nozzle is connected with the gas introduction port , such that the purge gas (G1) is supplied to an inside (Fa) of the container (F) being positioned in the purge position; wherein the purge controller is configured to control the purge nozzle such that the blowing of the purge gas (G1) in the cleaning state is effected when the bottom surface (Fb) of the container (F) to be purged and the purge nozzle face each other and a gap (GA) between the bottom surface (Fb) of the container (F) and a top surface of the purge nozzle is such that the purge gas (G1) blown through the purge nozzle reaches the bottom surface (Fb) of the container (F), with the purge nozzle not yet being connected with the gas introduction port , and that the blowing of the purge gas (G1) in the cleaning state starts after that the conveyance of the container (F) by the conveyance means to the purge position has started. <EOS>