Method and system for continuous-flow aerobic granular sludge process with improved two-stage sedimentation

A method for a continuous-flow aerobic granular sludge (AGS) process with an improved two-stage sedimentation, comprising the following steps:

• (1) arranging a biochemical reaction tank, a granular sludge sedimentation tank, and an inclined plate sedimentation tank, wherein the biochemical reaction tank, the granular sludge sedimentation tank, and the inclined plate sedimentation tank are separate tanks connected sequentially, and arranging an inclined device inside the inclined plate sedimentation tank;
• (2) allowing sewage to continuously flow into the biochemical reaction tank, and allowing a sludge-water mixture obtained after a biochemical reaction to enter the granular sludge sedimentation tank, wherein a sludge return pipe communicating with the biochemical reaction tank is provided at a bottom of the granular sludge sedimentation tank, and heavy sludge in the sludge-water mixture is settled in the granular sludge sedimentation tank and returned to the biochemical reaction tank;
• and
• (3) allowing light flocculent sludge in the sludge-water mixture in step (2) to flow into the inclined plate sedimentation tank and adding a chemical coagulant in the front of the inclined plate sedimentation tank through an agent-feeding device communicating with a front end of the inclined plate sedimentation tank, wherein the light flocculent sludge is separated by the inclined device, pooled at a lower part of the inclined plate sedimentation tank, and discharged out of the system through a surplus sludge discharge port at a bottom of the inclined plate sedimentation tank.