activated sludge settling tank的用法和样例：
- The simulation and the model of activated sludge process reactor with secondary settling tank
- Aerobic Digestion most commonly used for the initial treatment from a sewage treatment system sedimentation tank the remainder of activated sludge.
- Over 300 strains of bacteria have been found in activated sludge.
- Acetate was degraded by denitrifying activated sludge.