biological water treatment plant uses round settlers

biological water treatment plant round settlers effluent wastewater clarifiers microorganisms bacteria organic contaminants filtration aerobic anaerobic process sedimentation purification system sludge disposal oxygenation nutrients denitrification denitrifiers nitrification nitrifiers bod cod ammonia phosphorus removal settlement gravitational conditioning treated microbes decomposition settling flocculation algae chlorination demineralization disinfection reuse retention tank sustainability aigenerated