waste water engineering MCQs – Page 4

Practise focused waste water engineering questions with marked answers for exam preparation and subject revision.

waste water engineering Mcqs

61. The sewers___________________?
0

A. Must be of adequate size to avoid over flow

B. Must flow under gravity to full

C. Must be laid at least 2 to 3 m deep to collect /water from the basements

D. All the above

62. Cowl is provided at___________________?
0

A. Lower end of ventilating column

B. Upper end of the manhole

C. First step in manhole

D. Upper end of ventilating column

63. With self cleansing velocity in sewers___________________?
0

A. Silting occurs at bottom

B. Scouring occurs at bottom

C. Both silting and scouring occur at bottom

D. Neither silting nor scouring occurs at bottom

64. In olden days the type of section adopted in trunk and out fall sewers was__________________?
0

A. Horse shoe shaped

B. Parabolic shaped

C. Egg shaped

D. Circular shaped

65. Design period of 40 to 50 years is adopted for_________________?
0

A. All the above

B. Branch sewers

C. Trunk sewers

D. Main sewers

66. In a grit chamber of a sewage treatment plant ____________________?
0

A. Depth of 0.9 m to 1.20 m is kept

B. All the above

C. Flow velocity 0.15 m to 0.3 m/sec is kept

D. One minute of detention period is kept

67. Large diameter sewers subjected to external pressure alone, are reinforced ______________________?
0

A. Near the inner surface of the pipe

B. Near the outer surface of the pipe

C. Both A. and B.

D. With elliptical cage

68. The arrangement made for passing the sewer line below an obstruction below the hydraulic gradient lines called ____________________?
0

A. all of these

B. Sag pipe

C. Depressed sewer

D. Inverted syphon

69. The small sewers are cleaned by____________________?
0

A. Flushing

B. Cane rodding

C. None of these

D. Wooden pills

70. The most efficient cross-section of sewers in a combined sewerage system is________________?
0

A. Parabolic

B. Rectangular

C. Circular

D. New egged

71. Pick up the correct statement from the following?
0

A. The sewers may be carried up and down the hills and valleys

B. The water supply pipes carry pure water free from solid particles

C. The sewer pipes are generally laid along level hills

D. The water supply pipes get clogged if flow velocity is less than self cleansing velocity

72. Oxidation process results in the formation of___________________?
0

A. Carbon dioxide

B. Nitrates

C. All the above

D. Sulphates

73. To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of_______________?
0

A. Sulphuric acid

B. Nitric acid

C. Hydrochloric acid

D. Citric acid

74. Antisyphonage pipe is fitted_______________?
0

A. At the beginning of sewer line

B. On manholes

C. With a W.C. trap

D. At the end of septic tanks

75. The ratio of depths at partial flo________________?
0

A. 1

B. 1

C. (1

D. (1

76. A rain sanitary sewer is constructed to carry_________________ ?
0

A. Storm sewage

B. Surface water

C. Ground water

D. Sanitary sewage

77. In areas where rainy season is limited to a few months, the type of sewerage system recommended is__________________?
0

A. Combined system

B. Separate system

C. Partially separate system

D. None of these

78. In circular sewers if depth of flow is 0.2 times the full depth, the nominal gradient,______________?
0

A. Is doubled

B. Is trebled

C. Is only provided

D. Is not enough

79. The most efficient cross section of sewers in a separate sewerage system is__________________?
0

A. Rectangular

B. New egged

C. Parabolic

D. Circular

80. In the activated sludge process__________________?
0

A. Sludge is activated by constant stirring

B. Aeration is continued till stability

C. Aeration is done with an admixture of previously aerated sludge

D. Water is removed by centrifugal action

Previous Next

Showing 61 to 80 of 316 mcqs