water treatment 1

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water treatment 1
2014-11-10 19:50:20
water treatment

water treatment T1
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  1. What is the name of the particle size category that includes pathogens?
  2. Can colloidal particles be effectively removed by conventional sedimentation and or filtration?
  3. What treatment process destabilizes colloidal particles?
  4. Flocculation increases?
    particle size
  5. Flocculation is the
    Gentle mixing of coagulated water
  6. What is the name of the particle size category that is effectively removed by conventional sedimentation and filtration?
  7. What is the term for the visible suspended particles formed by gentle mixing of coagulated water?
  8. What is the term for over-mixing in flocculation that produces smaller particles?
  9. Flocculation Basin detention time (usual)
    20-30 minutes
  10. paddle mixers generally produce less
    Shear than turbine types
  11. What is the term for the hydraulic phenomenon where some water passes through a process more swiftly than the rest of the flow?
    Hydraulic short circuiting
  12. What is generally constructed between stages of a flocculation process to reduce short circuiting?
    Baffle Walls
  13. What would be the result of adding solid longitudinal baffles to a flocculation basin?
    Increased length to Width ratio and reduced short circuiting.
  14. long organic molecules that can link many colloidal particles together
    • Polymers:  
    • Cationic
    • Anionic
    • Nonionic
  15. The mechanism by which polymers work is called?
  16. Bridging makes particles
    • longer by linking them together along the polymer chain
    • and stronger less susceptible to shear.
  17. Detention time = ?
    Volume / Flow rate
  18. Dropping the mixing intensity from stage to stage is called?
    Tampered flocculation
  19. Mixing intensity is measured as
  20. what force causes suspended particles in sedimentation basins to exhibit a vertical velocity?
  21. what is the particle motion in a sedimentation basin that is produced by the flow of the water?
    Horizontal velocity
  22. In which of the following processes would we expect to see a reduction in turbidity from influent to effluent?
  23. Which of the following treatment processes is used to remove suspended particles from the water?
  24. Which of the following processes can be considered as a competition between horizontal and vertical particle velocities?
  25. How many gallons of water will be added to a 50-foot diameter storage tank in 8 hours, if the influent flow rate is 2.5 MGD?
  26. What processes must precede Sedimentation if this process is to be effective at removing colloidal particles?
    Coagulation and Flocculation
  27. If the level of accumulated sludge in a sedimentation basin becomes too high, what is the most appropriate Operator action?
    Increased frequency of sludge withdrawal cycles
  28. When flocculation mixing intensity drops from stage to stage, it is termed
    Tapered flocculation
  29. The water stream flowing into a unit treatment process is termed the
  30. Which of the following can lead to shear?Answers:
    Tapered mixing
    Short circuiting
    Static mixing
    High mixing energy
    Surface loading
    High mixing energy
  31. The purpose of flocculation is to
    Increase particle size
  32. Flocculation is an example of a
    Physical treatment process
  33. The hydraulic condition that allows some water to pass through a process faster than the theoretical detention time is called
  34. Which of the following may be employed to reduce short-circuiting in the flocculation process?
    Increased basin length-to-width ratio
    Use of multiple stages
    Baffles between stages
    Inlet baffles
    All the above
    All the above
  35. Which of the following treatment processes is used to remove suspended particles from the water?
  36. Which of the following processes can be considered as a competition between horizontal and vertical particle velocities?
  37. What are the two barriers to pathogens required by the SWTR?
    Removal and inactivation
  38. What is the SWTR req for reduction of viruses in a properly operated conventional plant?
    4 logs
  39. What swtr particle removal award for Giardia in a properly operated conventional plant?
    2.5 logs
  40. Slow sand filtraton flow rate
    .05 gpm/ft2 

    1 acre of land per 1mgd
  41. What is Schmutzdecke 
    Biological slime layer
  42. how much schmutzdecke is removed 
    3-6 inches is scrapped off
  43. DE filters common used on
    pools and spas
  44. in addition to slow sand filtration which swtr approved tech removes most particles via the straining mechanism?
    diatamaceous Earth filtration
  45. What are the four unit processes that combine to form conventional treatment?
    Coagulation, Flocculation, Sedimentation, and Filtration.
  46. Filter types
    • Pressure or Gravity
    • Filtration rate
    • media configurations
    • Rate of flow control
  47. Filtration Rates by type
    • slow sand
    • .05gpm 3ft sand 
    • Rapid sand
    • 2gpm 3ft sand
    • High Rate
    • 2-6 gpm various media
  48. What is the SWTR classification for a filter that operates at a filtration rate of between 2 and 6 gpm
    High rate filtration
  49. Which of the following is expressly prohibited under the surface water treatment rule?
    • Gravity filtration 
    • Pressure filtration
  50. What is the term for monomedium filters with filtration rates upto 2 gpm
    Rapid sand filtration
  51. What is the filter component that evenly distributes the clean water being used to backwash a filter?
  52. The most common filter media
  53. upper layer in a dual media filter?
    Anthracite Coal
  54. What is the term for the removal of trapped suspended particles
  55. Waste stream generated by a filter backwash?
    Waste washwater
  56. mechanical device used to control the rate of flow or the overall head loss through a filter
    Effluent valve
  57. what processes from conventional treatment are considered as pretreatment for filtration?
    Coagulation and flocculation
  58. What polymer types are commonly used as filter aids?
    Anionic and nonionic polymers
  59. term for the mechanism used by polymers to ling particles together
  60. What are the two most likely events that would necessitate a backwash
    Terminal headloss and turbidity breakthrough
  61. term for the additional energy applied to a filter for a more thorough washing operation?
    Supplemental scour
  62. What is the form of supplemental scour used with most deep bed filters
    compressed air
  63. Under ideal growth conditions, after several hours a single bacterium can reproduce to form a visible
  64. What is the most important general water quality difference between surface water and ground water?
    Surface water may have pathogens
  65. Into which category of microorganisms would we place Giardia?
  66. In terms of their physical size, microorganisms are classified as
  67. What types of molecules comprise most of the cell wall of a typical bacterium?
  68. What is the term used to designate something as being a living entity?
  69. Which of the following is a form of microorganism?
    All of the above
  70. What are the chemical products formed during aerobic respiration?
    Carbon monoxide and carbon dioxide
  71. Which of the following laboratory analyses will detect the largest number of different kinds of microorganisms?
    Heterotrophic plate count
  72. Brilliant green bile is an essential ingredient in which of the following?
    Confirmed test
  73. Which of the following is a protozoan?
  74. How long will it take to obtain test results using the ColiLert method?
    24 hours
  75. MMO-MUG is an essential ingredient in which of the following laboratory analyses?
  76. What steps must be taken when a single routine sample tests positive for total coliform?
    Re-test a new sample taken from the original sample point, plus at two additional points upstream and downstream.
  77. Which of the following is a step in the Multiple Tube fermentation analysis?
    All of the above
  78. Gas withdrawal rates
    100-150lb container
    1 ton 
    90 ton
    • 40lbs a day
    • 400 lbs a day
    • withdrawn as a liquid is unlimited
  79. Specialized repair kit for chlorine containers
    • A kit 100/150 lb cylinder
    • B 1 ton
    • C rail cars
  80. Calcium Hypochlorite facts
    • Ca(OCl)2
    • 65% available chlorine
    • wont degrade over time
    • HTH trade name
  81. Sodium Hypochlorite
    • 12.5% chlorine
    • Degrades over time
    • AKA bleach
  82. What are the three chem used to chlorinate drinking water?
    • elemental chlorine (gas)
    • Calcium Hypochlorite (solid) 65%
    • Sodium Hypochlorite (liquid) 12.5%
  83. Chlorine of any form will form ------ when dissolved in water.
    Free chlorine ( hypochlorous acid)
  84. Liquid and Solid chlorine raise
    while gas chlorine lowers
  85. HOCl
    Hypochlorous Acid AKA (free chlorine)

    Hydrochloric Acid AKA Muriatic Acid
  86. what is the main chemical form of free chlorine?
    Hypochlorous Acid
  87. When hypochlorous acid dissociates what ion is produced?
    Hypoochlorite Ion
  88. What is and indicator of raw water quality?
    Chlorine demand
  89. What is used in CT calculations
    Chlorine residual
  90. PEL limit
    Permissible Exposure limit:  1 ppm

    Immediately Dangerous to Life and Health: 10ppm
  91. Na(OCl)
    Sodium hypochlorite liquid (bleach)
  92. Cl2
    Chlorine gas
  93. Ca(OCl)2
    Calcium Hypochlorite Granules
  94. How much Gaseous chlorine can be delivered in a single day by a one ton container?
  95. What device is used to generate the vacuum under which a gas chlorine feed system operates?
  96. Where is chlorine typically applied to adjust the residual in the distribution system?
    Plant Effluent
  97. What is the residual chlorine measurement method for most online analyzers?
  98. What is the field method for measuring residual chlorine levels in grab samples?
    DPD Colorimetric method
  99. how long does the DPD method take
    3 minutes
  100. What is the first step to resolving a liquid chlorine leak?
    rote the container so that the leak contains only gas
  101. What is used to form the seal between a nes gas chlorine container and a plants permanent chlorine piping?
    A new lead gasket
  102. What causes erosion corrosion  in copper tubing
    Water velocities over 5ft per second.
  103. Water with a higher dissolved solids content has a greater potential for?
    Corrosion due to increased conductivity 
  104. What is the most common type of corrosion cell
    Oxygen cell 
  105. A thin film or coating of Calcium carbonate can drastically,,,
    inhibit corrosion
  106. advantage of  Zinc treatments for corrosion control
    less scale prevents deterioration of asbestos cement pipe.