Tag: wastewater treatment - need and methods

Questions Related to wastewater treatment - need and methods

In a filtration plant, water is filtered using layers of 

  1. sand

  2. oil

  3. sand and clay

  4. sand, fine gravel and medium gravel


Correct Option: D

Which of the following is/are useful ways of utilizing waste water?

  1. Certain pollutants in sewage water can become fertilizer for various crops.

  2. Waste water can be used for recharging the ground water.

  3. Waste water can be used for irrigation.

  4. All of the above.


Correct Option: D
Explanation:
Waste water can be used for multiple purposes as mentioned below-
(a) For recharging the groundwater.
(b) It can be used for irrigation.
(c) Treated municipal water can be used for washing cars and watering the gardens.
(c) Certain pollutants in sewage water can be used as fertilizers for various crops.
Therefore, the correct answer is option D.

Which is first stage of waste treatment plant?

  1. Preliminary Treatment

  2. Primary Treatment

  3. Secondary Treatment

  4. Tertiary Treatment


Correct Option: A

Activated sludge acts as inoculum in:

  1. Primary treatment

  2. Secondary treatment

  3. Tertiary treatment

  4. More that one option


Correct Option: A
Explanation:

A.Primary treatment – Removal of large and small particles from sewage through sequential filtration and sedimentation is called primary treatment.

B.Secondary treatment – It involves biological process of microbial degradation of organic matter contained in sewage effluent. In this activated sludge acts an inoculum.

C.Tertiary treatment – There is no occurrence of tertiary sewage treatment.

So, the correct option is ‘Secondary treatment’.    

Which process involved in waste water convertion into drinkable water?

  1. Precipitation

  2. Condensation

  3. Filtration

  4. Nutrient cycle


Correct Option: C