WATER CIRCULATING DEVICE OF FLUSH TOILET

PROBLEM TO BE SOLVED: To provide a water circulating device of a flush toilet capable of remarkably saving the quantity of city water used to lighten the load of sewage disposal, and heightening the processing capability of circulating water to exhibit a good effect in view of sanitation. SOLUTION: This water circulating device is provided with a lower tank 2 for storing drain discharged from a toilet stool 50, an aeration tank 10 for aerating drain (a) pumped up from the lower tank 2 by a blower pump 4, a first separating tank 20 for storing the drain sent from the aeration tank 10 to be separated into fresh water (a') and sludge (b), an air lift pump 21 for discharging the sludge (b) settled in the first separating tank 20 to a sewerage, a second separating tank 30 for storing fresh water a' sent from an upper layer part of the first separating tank 20 to be further separated into the fresh water a" and sludge b, and an air lift pump 31 for discharging the sludge b in the second separating tank 30 to the sewerage.