Quiznetik

Waste Water Treatment | Set 2

1. Which of the following option is incorrect about the sludges?

Correct : C. Formed generally at heated portions of the boiler

2. The propulsion of water into steam drum by extremely rapid, almost explosive boiling of water at the heating surface is called ___________

Correct : B. Priming

3. The phenomenon during which the boiler material becomes brittle due to accumulation of caustic substances is known as ___________

Correct : D. Caustic embrittlement

4. Foaming is caused by the formation of ___________

Correct : C. Oils and alkalis

5. The term ‘Sullage’ refers to:

Correct : C. Wastewater from kitchen, laundry

6. Wastewater can become septic by the loss of:

Correct : A. Dissolved oxygen content

7. Which one of the below is not an attribute of drinking water?

Correct : D. Source

8. The extent of water treatment depends on how many factors?

Correct : B. 2

9. What is added to the water treatment tank to settle the colloidal particles?

Correct : B. Alum and lime

10. Disinfection of water in our country is mainly done by ____________

Correct : C. Chlorination

11. Which minerals and in what form are present in ground water?

Correct : A. Fe & Mn in Ferrous and Manganous

12. How many types of wastewater treatment plants are there based on the type of wastewater?

Correct : D. 3

13. On how many conditions does the intervention of wastewater depend on?

Correct : B. 7

14. The surface water quality is affected by _______ and infiltration from rainfall.

Correct : B. Run off

15. _________ are constructed for water supply, electricity generation, recreation, irrigation and others.

Correct : C. Reservoirs

16. What is the next step after water abstraction in wastewater treatment?

Correct : B. Treatment

17. Which of the following requires aesthetically pleasant water?

Correct : B. Industrial use

18. The addition of substances or energy forms that directly or indirectly alter the nature of the water body is called?

Correct : B. Water pollution

19. What is the type of pollution where the pollutants reach the water body in points called?

Correct : A. Point-source pollution

20. What percentage of solids does wastewater contain?

Correct : C. 0.1%

21. What is the growth of huge amounts of algae and other aquatic plants leading to the deterioration of the water quality called?

Correct : A. Eutrophication

22. The optimum temperature for bacterial activity is in what range?

Correct : A. 25-35 degree Celsius

23. The fluoride concentration for prevention of dental caries is ____________

Correct : A. 1mg/l

24. In which process, the fluoride content of water is raised?

Correct : B. Fluoridation

25. Which of the following is not used as a fluoride compound?

Correct : D. Sodium fluro carbonate

26. Which of the following is the pure compound?

Correct : A. Sodium fluoride

27. As far as safer handling is considered, which of the following is used for fluoridation?

Correct : C. Hydrofluosilicic acid

28. What happens when water contains 8-20 ppm of fluoride concentration?

Correct : B. Crippling fluorosis

29. The process of reducing the fluoride content from water is called _____

Correct : C. Defluoridation

30. Which of the following is not used for defluoridation?

Correct : B. Copper sulfate

31. At which temperature, the bone is calcinated during defluoridation with calcium phosphate?

Correct : C. 400-600oC

32. One cubic metre of bone can treat how much quantity of water containing 3.5 ppm of fluoride?

Correct : B. 100m3

33. Which material is used in contact filters for the removal of fluorides?

Correct : C. Synthetic tri-calcium phosphate

34. Which material is used for removing fluorides from hard water containing 3ppm of fluorides?

Correct : A. Lime

35. Fluorex is a special mixture of ____________

Correct : B. Tri-calcium phosphate and hydroxyapatite

36. Which of these materials is not added to iron for improving its oxidation resistance?

Correct : D. Silicon

37. How much chromium is required to provide oxidation resistance for use over 1000oC?

Correct : D. 17%

38. Molybdenum with hydrogen can be used up to ________

Correct : B. 1500oC

39. % chromium mixed with ______ can be used up to 1100oC.

Correct : A. Nickel

40. Which of these metals does not require alloying for oxidation resistance?

Correct : C. Aluminum

41. _________ is used to prevent duralumin from corrosion.

Correct : D. Alclad

42. Galvanized ion is made by dipping low carbon steel in molten zinc at ________

Correct : D. 450oC

43. Which of these is not a way to prevent intergranular corrosion?

Correct : D. Reduction of alloying elements

44. Dezincification of brass is prevented by addition of ________

Correct : C. Arsenic

45. Season-cracking can be prevented by cold-working of brass at _________

Correct : C. 300oC

46. How can caustic embrittlement be avoided?

Correct : D. Adding tannins

47. A grit chamber is usually installed ______ primary sedimentation tanks.

Correct : A. Before

48. At what velocity will the particles settle down?

Correct : B. 0.3 m/s

49. Grit chambers are constructed to prevent their accumulation in _______

Correct : B. Sludge digesters

50. What is the cleaning period for manual grit chambers?

Correct : D. 1 week

51. Grit chamber is similar to which of the following?

Correct : B. Sedimentation tank

52. What is the specific gravity of settleable particles in the grit chamber?

Correct : C. 2.65

53. Stoke’s law holds good for Reynolds’s number ______

Correct : A. Less than 1

54. What is the horizontal velocity considered for grit chamber?

Correct : A. 0.25-0.4m/sec

55. What is the detention time considered for aerated grit chamber?

Correct : B. 2-5 mins

56. Which of these is not a grit removal equipment installed in the aerated grit chamber?

Correct : D. Communitors

57. What is the amount of air supplied for these grit chambers?

Correct : B. 0.2-0.5 m3/m.min

58. At what depth are the air diffusers placed in the grit chamber?

Correct : D. 0.45-0.6 m

59. What is the amount of grit quantities captured by the aerated grit chamber?

Correct : A. 0.004-0.20 m3/103.m3

60. Usually while designing what is the range of the width of the aerated grit chamber assumed?

Correct : C. 2.5-7.0m

61. Usually while designing what is the range of length of the aerated grit chamber assumed?

Correct : A. 7.5-20

62. Usually while designing what is the range of depth of the aerated grit chamber assumed?

Correct : C. 2-5 m

63. Aerated grit chambers are usually designed to remove particles in which range of size?

Correct : C. 0.21 mm diameter

64. Activated sludge process degrade organics and _________

Correct : B. Remove nutrients

65. What is required to keep the activated sludge suspended?

Correct : C. Oxygen

66. What does the bacterium use to grow?

Correct : B. Organic pollutants

67. ________ combines aeration basin and secondary clarifier into single unit.

Correct : C. Sequential batch reactor

68. What does SBR stand for?

Correct : D. Sequential batch reactor

69. SBR operates as ________ process.

Correct : A. Batch

70. When the aeration system shuts off, the basin begins to perform as a ______

Correct : B. Secondary clarifier

71. _______ provides the dual purpose of providing DO and mixing of the mixed liquor and wastewater.

Correct : B. Aeration

72. Ion-exchange resin is ____________

Correct : C. Organic polymer with porous structure

73. Which of the following ion get released from the cation exchange column?

Correct : A. H+

74. Which of the following ion get released from the anion exchange column?

Correct : B. OH–

75. Ion-free water coming out from the exchanger is known as ____________

Correct : D. Demineralised water

76. Which of the following statement is incorrect about the demineralised water?

Correct : C. It is fit for domestic use

77. The exhausted cation exchange column is regenerated by passing a solution of ____________

Correct : A. Dil. HCl

78. The exhausted anion exchange column is regenerated by passing a solution of ____________

Correct : D. Dil. NaOH

79. In ion-exchange process, the capital cost is _________ and the operational expenses are ______________

Correct : C. High, high

80. The residual hardness in ion-exchange process is ____________

Correct : A. 0-2 ppm

81. How many oxygen atoms are present in the ozone?

Correct : C. 3

82. _______ is produced by subjecting oxygen to high electric voltage.

Correct : D. Ozone

83. Which of the following can be inactivated using ozone?

Correct : C. Protozoa

84. Which of these is not an advantage of Ozonation?

Correct : C. Equipment costs

85. Which of the following is not a disadvantage of Ozonation?

Correct : A. Chemicals

86. Which of the following is not removed by Ozonation?

Correct : C. Magnesium

87. What is the maximum time required for ozone degradation?

Correct : B. 30 minutes

88. What is the average ozone concentration created during Ozonation?

Correct : C. 10000 mg/l

89. Which of the following is not correct regarding Ozonation?

Correct : D. Operational costs are low

90. What is the colour of ozone?

Correct : D. Colourless

91. Ozone is formed by the interaction of _______

Correct : A. UV or O2

92. In which year was the structure of ozone determined?

Correct : A. 1865

93. In which year was the ozone named?

Correct : B. 1839

94. At what pH ozonation is carried out?

Correct : A. 8

95. Photo catalysis uses which of the following methods to produce free radicals?

Correct : B. UV + TiO2

96. How is the electrical requirement for the ozonation process expressed mathematically?

Correct : A. EE/O =EEt/ Vlog(Ci-Cf)

97. What are the byproducts of the breakdown of the organic compounds by UV rays?

Correct : B. CO2 + H2O

98. In what range is the EE/O present in order to reduce one log of reduction?

Correct : B. 20-265 KWH

99. Primary sludge includes __________

Correct : D. Settleable solids

100. Which of the following methods are used in rural communities?

Correct : D. Composting