A dream detection system includes a mask and a control unit. The method comprises: a step of receiving, from the base station, a first message containing an available interval or an M2M device ID shared among M2M devices, and an M2M device ID use period in which said available interval periodically repeats; and a step of transceiving data tofrom the base station using the M2M device ID in the available interval. The stream is collected at the bottom of the first chamber, and is re-circulated to a manifold and liquid distributor assembly in a second chamber in the same vessel.