Quiznetik
Waste Water Treatment | Set 2
1. Which of the following option is incorrect about the sludges?
A. Sludges are soft, loose and slimy precipitate
B. They are non-adherent deposits and can be easily removed
C. Formed generally at heated portions of the boiler
D. Can be removed by blow down operation
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 ___________
A. Foaming
B. Priming
C. Corrosion
D. Caustic embrittlement
Correct : B. Priming
3. The phenomenon during which the boiler material becomes brittle due to accumulation of caustic substances is known as ___________
A. Foaming
B. Priming
C. Corrosion
D. Caustic embrittlement
Correct : D. Caustic embrittlement
4. Foaming is caused by the formation of ___________
A. Acids
B. Alcohols
C. Oils and alkalis
D. Ketones
Correct : C. Oils and alkalis
5. The term ‘Sullage’ refers to:
A. Fresh wastewater
B. Septic wastewater
C. Wastewater from kitchen, laundry
D. Toxic wastewater
Correct : C. Wastewater from kitchen, laundry
6. Wastewater can become septic by the loss of:
A. Dissolved oxygen content
B. Carbon content
C. Organic compounds
D. Water content
Correct : A. Dissolved oxygen content
7. Which one of the below is not an attribute of drinking water?
A. Aesthetics
B. Economic
C. Safety
D. Source
Correct : D. Source
8. The extent of water treatment depends on how many factors?
A. 5
B. 2
C. 3
D. 4
Correct : B. 2
9. What is added to the water treatment tank to settle the colloidal particles?
A. Alum
B. Alum and lime
C. Lime
D. Potash
Correct : B. Alum and lime
10. Disinfection of water in our country is mainly done by ____________
A. Oxygenation
B. Hydration
C. Chlorination
D. Filtration
Correct : C. Chlorination
11. Which minerals and in what form are present in ground water?
A. Fe & Mn in Ferrous and Manganous
B. Fe & Cu in Ferric and Cupric
C. Fe & Mn in Ferric and manganous
D. Cu & Mn in Cuprous and manganous
Correct : A. Fe & Mn in Ferrous and Manganous
12. How many types of wastewater treatment plants are there based on the type of wastewater?
A. 5
B. 4
C. 2
D. 3
Correct : D. 3
13. On how many conditions does the intervention of wastewater depend on?
A. 5
B. 7
C. 6
D. 4
Correct : B. 7
14. The surface water quality is affected by _______ and infiltration from rainfall.
A. Precipitation
B. Run off
C. Wetlands
D. Farming
Correct : B. Run off
15. _________ are constructed for water supply, electricity generation, recreation, irrigation and others.
A. Swimming pools
B. Ponds
C. Reservoirs
D. Tanks
Correct : C. Reservoirs
16. What is the next step after water abstraction in wastewater treatment?
A. Supply to consumers
B. Treatment
C. Combine with stormwater
D. Supply to receiving body
Correct : B. Treatment
17. Which of the following requires aesthetically pleasant water?
A. Domestic use
B. Industrial use
C. Irrigation
D. Aquaculture
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?
A. Water contamination
B. Water pollution
C. Sanitation
D. Water treatment
Correct : B. Water pollution
19. What is the type of pollution where the pollutants reach the water body in points called?
A. Point-source pollution
B. Diffuse pollution
C. Point-source contamination
D. Diffuse contamination
Correct : A. Point-source pollution
20. What percentage of solids does wastewater contain?
A. 0.5%
B. 5%
C. 0.1%
D. 1%
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?
A. Eutrophication
B. Algae growth
C. Nitrification
D. Denitrification
Correct : A. Eutrophication
22. The optimum temperature for bacterial activity is in what range?
A. 25-35 degree Celsius
B. 50 degree Celsius
C. 20 degree Celsius
D. 40 degree Celsius
Correct : A. 25-35 degree Celsius
23. The fluoride concentration for prevention of dental caries is ____________
A. 1mg/l
B. 2mg/l
C. 3mg/l
D. 4mg/l
Correct : A. 1mg/l
24. In which process, the fluoride content of water is raised?
A. Chlorination
B. Fluoridation
C. Defluoridation
D. Flocculation
Correct : B. Fluoridation
25. Which of the following is not used as a fluoride compound?
A. Sodium fluoride
B. Sodium silico fluoride
C. Hydrofluosilicic acid
D. Sodium fluro carbonate
Correct : D. Sodium fluro carbonate
26. Which of the following is the pure compound?
A. Sodium fluoride
B. Sodium silico fluoride
C. Hydrofluosilicic acid
D. Sodium fluro carbonate
Correct : A. Sodium fluoride
27. As far as safer handling is considered, which of the following is used for fluoridation?
A. Sodium fluoride
B. Sodium silico fluoride
C. Hydrofluosilicic acid
D. Sodium fluro carbonate
Correct : C. Hydrofluosilicic acid
28. What happens when water contains 8-20 ppm of fluoride concentration?
A. Blue baby disease
B. Crippling fluorosis
C. Dental fluorosis
D. Mottling of teeth
Correct : B. Crippling fluorosis
29. The process of reducing the fluoride content from water is called _____
A. Chlorination
B. Fluoridation
C. Defluoridation
D. Flocculation
Correct : C. Defluoridation
30. Which of the following is not used for defluoridation?
A. Calcium phosphate
B. Copper sulfate
C. Alum
D. Bone charcoal
Correct : B. Copper sulfate
31. At which temperature, the bone is calcinated during defluoridation with calcium phosphate?
A. 100-200oC
B. 200-300oC
C. 400-600oC
D. 500-800oC
Correct : C. 400-600oC
32. One cubic metre of bone can treat how much quantity of water containing 3.5 ppm of fluoride?
A. 10m3
B. 100m3
C. 1000m3
D. 10000m3
Correct : B. 100m3
33. Which material is used in contact filters for the removal of fluorides?
A. Calcium phosphate
B. Copper sulfate
C. Synthetic tri-calcium phosphate
D. Bone charcoal
Correct : C. Synthetic tri-calcium phosphate
34. Which material is used for removing fluorides from hard water containing 3ppm of fluorides?
A. Lime
B. Copper sulfate
C. Synthetic tri-calcium phosphate
D. Bone charcoal
Correct : A. Lime
35. Fluorex is a special mixture of ____________
A. Di-calcium phosphate and carbon
B. Tri-calcium phosphate and hydroxyapatite
C. Di-calcium phosphate and phosphoric acid
D. Tri-calcium phosphate and carbon
Correct : B. Tri-calcium phosphate and hydroxyapatite
36. Which of these materials is not added to iron for improving its oxidation resistance?
A. Nickel
B. Chromium
C. Aluminum
D. Silicon
Correct : D. Silicon
37. How much chromium is required to provide oxidation resistance for use over 1000oC?
A. 1%
B. 6%
C. 12%
D. 17%
Correct : D. 17%
38. Molybdenum with hydrogen can be used up to ________
A. 1000oC
B. 1500oC
C. 2000oC
D. 4000oC
Correct : B. 1500oC
39. % chromium mixed with ______ can be used up to 1100oC.
A. Nickel
B. Chromium
C. Aluminum
D. Silicon
Correct : A. Nickel
40. Which of these metals does not require alloying for oxidation resistance?
A. Iron
B. Copper
C. Aluminum
D. Molybdenum
Correct : C. Aluminum
41. _________ is used to prevent duralumin from corrosion.
A. Iron
B. Kynal
C. Titanium
D. Alclad
Correct : D. Alclad
42. Galvanized ion is made by dipping low carbon steel in molten zinc at ________
A. 100oC
B. 150oC
C. 200oC
D. 450oC
Correct : D. 450oC
43. Which of these is not a way to prevent intergranular corrosion?
A. Reduction of carbon level
B. Quenching
C. Addition of carbide forming elements
D. Reduction of alloying elements
Correct : D. Reduction of alloying elements
44. Dezincification of brass is prevented by addition of ________
A. Nickel
B. Zinc
C. Arsenic
D. Tungsten
Correct : C. Arsenic
45. Season-cracking can be prevented by cold-working of brass at _________
A. 15oC
B. 100oC
C. 300oC
D. 550oC
Correct : C. 300oC
46. How can caustic embrittlement be avoided?
A. Addition of nickel
B. Increasing potential
C. Decreasing carbon
D. Adding tannins
Correct : D. Adding tannins
47. A grit chamber is usually installed ______ primary sedimentation tanks.
A. Before
B. After
C. In between
D. In
Correct : A. Before
48. At what velocity will the particles settle down?
A. 0.5 m/s
B. 0.3 m/s
C. 0.1 m/s
D. 0.25 m/s
Correct : B. 0.3 m/s
49. Grit chambers are constructed to prevent their accumulation in _______
A. Sedimentation tank
B. Sludge digesters
C. Coagulation tank
D. Sand filter
Correct : B. Sludge digesters
50. What is the cleaning period for manual grit chambers?
A. 3 days
B. 5 days
C. 48 hours
D. 1 week
Correct : D. 1 week
51. Grit chamber is similar to which of the following?
A. Screening unit
B. Sedimentation tank
C. Coagulation tank
D. Sand bed
Correct : B. Sedimentation tank
52. What is the specific gravity of settleable particles in the grit chamber?
A. 2.98
B. 2.56
C. 2.65
D. 2.89
Correct : C. 2.65
53. Stoke’s law holds good for Reynolds’s number ______
A. Less than 1
B. Equal to 1
C. Greater than 1
D. Nearer to 1
Correct : A. Less than 1
54. What is the horizontal velocity considered for grit chamber?
A. 0.25-0.4m/sec
B. 0.6-0.9 m/sec
C. 1-2 m/sec
D. 3-4m/sec
Correct : A. 0.25-0.4m/sec
55. What is the detention time considered for aerated grit chamber?
A. 5-6 mins
B. 2-5 mins
C. 1-2 mins
D. 3-4 mins
Correct : B. 2-5 mins
56. Which of these is not a grit removal equipment installed in the aerated grit chamber?
A. Screw conveyers
B. Tubular conveyers
C. Jet pumps
D. Communitors
Correct : D. Communitors
57. What is the amount of air supplied for these grit chambers?
A. 1-2 m3/m.min
B. 0.2-0.5 m3/m.min
C. 0.5-0.8 m3/m.min
D. 0.8-1 m3/m.min
Correct : B. 0.2-0.5 m3/m.min
58. At what depth are the air diffusers placed in the grit chamber?
A. 0.6-0.9 m
B. 1-2 m
C. 0.1-0.4m
D. 0.45-0.6 m
Correct : D. 0.45-0.6 m
59. What is the amount of grit quantities captured by the aerated grit chamber?
A. 0.004-0.20 m3/103.m3
B. 0.25 m3/103.m3
C. <0.004 m3/103.m3
D. 0.5 m3/103.m3
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?
A. 0.5-2 m
B. 8-10 m
C. 2.5-7.0m
D. 12m
Correct : C. 2.5-7.0m
61. Usually while designing what is the range of length of the aerated grit chamber assumed?
A. 7.5-20
B. 4-6 m
C. 25 m
D. 50 m
Correct : A. 7.5-20
62. Usually while designing what is the range of depth of the aerated grit chamber assumed?
A. 0.5-2 m
B. 8-10 m
C. 2-5 m
D. 12 m
Correct : C. 2-5 m
63. Aerated grit chambers are usually designed to remove particles in which range of size?
A. 0.1mm diameter
B. 0.35 mm diameter
C. 0.21 mm diameter
D. 0.41 mm diameter
Correct : C. 0.21 mm diameter
64. Activated sludge process degrade organics and _________
A. Improve nutrients
B. Remove nutrients
C. Remove odour
D. Remove taste
Correct : B. Remove nutrients
65. What is required to keep the activated sludge suspended?
A. Carbon-dioxide
B. Nitrogen
C. Oxygen
D. Ammonia
Correct : C. Oxygen
66. What does the bacterium use to grow?
A. Oxygen
B. Organic pollutants
C. Water
D. Carbon-dioxide
Correct : B. Organic pollutants
67. ________ combines aeration basin and secondary clarifier into single unit.
A. Primary clarifier
B. Aerobic unit
C. Sequential batch reactor
D. Secondary clarifier
Correct : C. Sequential batch reactor
68. What does SBR stand for?
A. Secondary batch reactor
B. Sequential biological reactor
C. Secondary biological reactor
D. Sequential batch reactor
Correct : D. Sequential batch reactor
69. SBR operates as ________ process.
A. Batch
B. Continuous
C. Semi-continuous
D. Discontinuous
Correct : A. Batch
70. When the aeration system shuts off, the basin begins to perform as a ______
A. Primary clarifier
B. Secondary clarifier
C. Anaerobic unit
D. Aeration unit
Correct : B. Secondary clarifier
71. _______ provides the dual purpose of providing DO and mixing of the mixed liquor and wastewater.
A. Flocculation
B. Aeration
C. Sedimentation
D. Clarification
Correct : B. Aeration
72. Ion-exchange resin is ____________
A. Linear
B. Low molecular weight
C. Organic polymer with porous structure
D. Soluble
Correct : C. Organic polymer with porous structure
73. Which of the following ion get released from the cation exchange column?
A. H+
B. Na+
C. K+
D. Ca+2
Correct : A. H+
74. Which of the following ion get released from the anion exchange column?
A. CO3-2
B. OH–
C. Cl–
D. SO4-2
Correct : B. OH–
75. Ion-free water coming out from the exchanger is known as ____________
A. Potable water
B. Disinfected water
C. Coagulated water
D. Demineralised water
Correct : D. Demineralised water
76. Which of the following statement is incorrect about the demineralised water?
A. It is as pure as distilled water
B. It is very good for use in high pressure boilers
C. It is fit for domestic use
D. It can be made either by distillation or by using cation and anion exchangers
Correct : C. It is fit for domestic use
77. The exhausted cation exchange column is regenerated by passing a solution of ____________
A. Dil. HCl
B. Dil. NaCl
C. Conc. HCl
D. Conc. NaCl
Correct : A. Dil. HCl
78. The exhausted anion exchange column is regenerated by passing a solution of ____________
A. Dil. KOH
B. Conc. KOH
C. Conc. NaOH
D. Dil. NaOH
Correct : D. Dil. NaOH
79. In ion-exchange process, the capital cost is _________ and the operational expenses are ______________
A. Low, high
B. High, low
C. High, high
D. Low, low
Correct : C. High, high
80. The residual hardness in ion-exchange process is ____________
A. 0-2 ppm
B. 5-10 ppm
C. 10-15 ppm
D. 20-30 ppm
Correct : A. 0-2 ppm
81. How many oxygen atoms are present in the ozone?
A. 1
B. 2
C. 3
D. 4
Correct : C. 3
82. _______ is produced by subjecting oxygen to high electric voltage.
A. Carbon-monoxide
B. Carbon-dioxide
C. Pure oxygen
D. Ozone
Correct : D. Ozone
83. Which of the following can be inactivated using ozone?
A. Algae
B. Fungi
C. Protozoa
D. All microbes
Correct : C. Protozoa
84. Which of these is not an advantage of Ozonation?
A. Reaction with bacteria
B. Organics degradation
C. Equipment costs
D. Chemicals
Correct : C. Equipment costs
85. Which of the following is not a disadvantage of Ozonation?
A. Chemicals
B. Costs
C. Energy
D. Fire hazard
Correct : A. Chemicals
86. Which of the following is not removed by Ozonation?
A. Iron
B. Manganese
C. Magnesium
D. Bacteria
Correct : C. Magnesium
87. What is the maximum time required for ozone degradation?
A. 15 minutes
B. 30 minutes
C. 45 minutes
D. 60 minutes
Correct : B. 30 minutes
88. What is the average ozone concentration created during Ozonation?
A. 1000 mg/l
B. 5000 mg/l
C. 10000 mg/l
D. 15000 mg/l
Correct : C. 10000 mg/l
89. Which of the following is not correct regarding Ozonation?
A. Does not requires chemicals
B. Eliminates bad taste
C. Eliminates odour
D. Operational costs are low
Correct : D. Operational costs are low
90. What is the colour of ozone?
A. Violet
B. White
C. Grey
D. Colourless
Correct : D. Colourless
91. Ozone is formed by the interaction of _______
A. UV or O2
B. O and O2
C. O and UV
D. O2 and CO
Correct : A. UV or O2
92. In which year was the structure of ozone determined?
A. 1865
B. 1875
C. 1885
D. 1895
Correct : A. 1865
93. In which year was the ozone named?
A. 1829
B. 1839
C. 1849
D. 1859
Correct : B. 1839
94. At what pH ozonation is carried out?
A. 8
B. 9
C. 11
D. 7
Correct : A. 8
95. Photo catalysis uses which of the following methods to produce free radicals?
A. UV rays
B. UV + TiO2
C. Ozone + UV
D. TiO2
Correct : B. UV + TiO2
96. How is the electrical requirement for the ozonation process expressed mathematically?
A. EE/O =EEt/ Vlog(Ci-Cf)
B. EE/O =EEt/ (Ci-Cf)
C. EE/O =EEt Vlog(Ci-Cf)
D. EE/O =EEt(Ci-Cf)
Correct : A. EE/O =EEt/ Vlog(Ci-Cf)
97. What are the byproducts of the breakdown of the organic compounds by UV rays?
A. CO
B. CO2 + H2O
C. H2CO3 and water
D. CO + H2O
Correct : B. CO2 + H2O
98. In what range is the EE/O present in order to reduce one log of reduction?
A. 0-20 KWH
B. 20-265 KWH
C. 265-365 KWH
D. 365-650 KWH
Correct : B. 20-265 KWH
99. Primary sludge includes __________
A. Total suspended solids
B. Suspended solids
C. Removable solids
D. Settleable solids
Correct : D. Settleable solids
100. Which of the following methods are used in rural communities?
A. Aerobic digestion
B. Mechanical dewatering
C. Dewatering
D. Composting
Correct : D. Composting