Provided is an apparatus for processing sewage by granulating activated
sludge and a method thereof. The sewage processing apparatus includes an
anaerobic granulation tank for granulating suspended microorganisms; an
indirect aeration tank for supplying oxygen to the supernatant
transported through a first transport pipe; an aerobic granulation tank
for granulating suspended microorganisms; and a discharge pipe for
discharging supernatant of finished water obtained after circulating a
series of the anaerobic granulation tank, the first transport pipe, the
indirect aeration tank, the aerobic granulation tank repeatedly.