ENVIRONMENTAL ENGINEERING IN CE QUIZ

In sewage treatment, its sedimentation is speeded up by commonly adding

Hydrochloric acid

Copper sulphate

Lime

Sodium sulphate

TRUE ANSWER : ?
YOUR ANSWER : ?

What are the methods of treatment & disposal of radioactive wastes?

Biological methods & adsorption in ion exchange materials

Fixing into a solid mass with cement and sinking deep in the sea

All of these

Evaporation & chemical precipitation

TRUE ANSWER : ?
YOUR ANSWER : ?

During sewage treatment, the sewage is subjected to __________ treatment in Imhoff tank.

Sedimentation

Filtration

Digestion

Both B and C

TRUE ANSWER : ?
YOUR ANSWER : ?

In a sedimentation tank, the detention period for water ranges from __________ hours.

2 to 4

16 to 20

24 to 32

8 to 12

TRUE ANSWER : ?
YOUR ANSWER : ?

Arsenic pollutant is not generated in____industries.

Tanneries

Glass & ceramic

Beverages

Any of these

TRUE ANSWER : ?
YOUR ANSWER : ?

The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the

Oxygen ion concentration

Relative stability

Bacterial stability factor

Biological oxygen demand (BOD)

TRUE ANSWER : ?
YOUR ANSWER : ?

Lagoons used for purification of polluted water

Gives an excellent final effluent (with 3 to 4 lagoons arranged in series) having suspended solid < 1 mg/litre and BOD = 3.8 mg/litre

Are large shallow artificial lakes also known as clarification lakes, maturation ponds or oxidation ponds

All of these

Use micro-organisms/bacteria in presence of dissolved oxygen

TRUE ANSWER : ?
YOUR ANSWER : ?

Thermal pollution of water increases its toxicity and oxidation of oxygen demanding waste besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of __________ present in it.

Coal ash

Potassium cyanide

None of these

Ortho-xylene

TRUE ANSWER : ?
YOUR ANSWER : ?

Oilish impurities present the effluent discharged from the electroplating industry is normally not removed by

Centrifugation

Floatation & skimming

Chemical coagulation

Ultrafiltration

TRUE ANSWER : ?
YOUR ANSWER : ?

Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels.

90

120

150

180

TRUE ANSWER : ?
YOUR ANSWER : ?