1. Surface Water Treatment Plant

2. Fig 4-8: Flow Diagram of conventional surface water treatment plant (“filtration plant”)

3. Coagulation = Charge reduction Flocculation = Contact of particles

4. Fig 4-10: Effect of salt on electric potential

5. Fig 4-11: Effect of valence on electric potential

6. Fig 4-8: Flow diagram of water softening plant

7. Alkalinity in Coagulation Needed to neutralize acid formed

8. Fig 4-13: results from jar test

9. Paddle Mixer Details

10. Paddle Mixers in Left Chamber and Flocculators in Right Two Chambers

11. Fig 4-35: Settling in an upflow clarifier

12. Fig 4-32: Zones of sedimentation on a horizontal flow clarifier

16. Fig 4-37: Partial solids removal in ideal sedimentation tank

19. Let’s say v 0 = 0.20 mm/s What % removal for particles with settling velocity = 0.15 mm/s?

31. Fig 4-43: Typical gravity filter box

33. Fig 4-44: Operation of rapid sand filter

34. Manual Control Panel in Water Treatment Plant

35. Lime slaker and feed system.

36. Upflow solids contact tank. Effluent weir on right.

37. Settling tank with radial weirs

38. Rapid sand filter with exposed under drain block. Wash water troughs run from left into gullet on right.

39. Rapid sand filter with water level just below backwash troughs. Note iron stain at high water line.

40. Rapid sand filter during filtration. Reflection shows water level above gullet and backwash troughs.

41. Rotameter used to measure flowrate of gaseous chlorine into water.

42. Hydrofluorosilicic acid drum and pump metering system for feeding fluoride into water.

43. Softening sludge lagoon. Winter view shows ice (light blue) where supernatant water is stnading.

44. Overview of water treatment plant showing sludge lagoons and building housing treatment facilities.