water treatment plant

aeration alga algae bacteria bacterias biologic biology circle circles circuit circuity circular clean cleaning clear clearing concrete cooling deter detergent dirty discharge eco ecological ecology effluent engineering environment environmentally flocculation flow grass green health modern organic pipes plant pollution pond ponds pool processing public purified purify recycle regeneration removal renew rotation round safe sanitary sanitation sedimentation separation sewage sewerage sludge smelly solids tank technical treat treatment turbidity waste water