1. Activated Sludge
It is a dense cluster of aerobic bacteria and microorganisms forming yellowish-brown flocs, specifically designed to consume pollutants in wastewater.
2. Aeration in the Aerobic Tank
The blower continuously supplies air to maintain high oxygen levels in the water, ensuring the bacteria have enough energy to survive and function effectively.
3. The Complete Treatment Process
Adsorption and Capture
When wastewater enters the aerobic tank, the highly adhesive activated sludge flocs capture and adsorb organic matter and suspended particles from the water.
Consumption and Decomposition
With sufficient oxygen, microorganisms break down the adsorbed pollutants as food:
They consume COD, BOD, organic matter, and some ammonia nitrogen.
Toxic and harmful substances are transformed into harmless compounds such as carbon dioxide, water, and nitrogen gas.
Purification and Separation
Once the pollutants are fully degraded, the wastewater becomes clean.
It then flows into the sedimentation tank, where the activated sludge settles to the bottom, and the clear water is discharged.
A portion of the settled sludge is recycled back to the anoxic tank to continue the treatment cycle.
Key Terms
Activated sludge: 活性污泥
Aerobic tank: 好氧池
Aeration: 曝气
COD: 化学需氧量
BOD: 生物需氧量
Sedimentation tank: 沉淀池
