Exercise

Fill in the blanks:

1. Wastewater released by houses is called ______.

Ans: sewage

2. Dried _____ is used as manure.

Ans: sludge

3. Algal bloom is also known as ______.

Ans:  eutrophication

4. The sewer system consists of a channel of ______ that carries out sewage from our houses.

Ans: pipelines

5. In primary treatment of sewage the material that floats at the top is called ______.

Ans: scum

Tick the correct answer:

1. Industrial effluent refers to

(a) wastes generated from cooking and bathing

(b) waste water generated from farms

(c) waste water generated due to mining

(d) wastes from industries

Ans: (d)

2. Sedimentary tanks are found in

(a) primary treatment stage

(b) secondary treatment stage

(c) tertiary treatment stage

(d) manhole

Ans: (a)

3. The nature of tertiary treatment is

(a) physical

(b) chemical                 

(c) biological

(d) all of the above

Ans: (b)

4. Sludge can be disposed through

(a) incineration

(b) dewatering   

(c) solids composting

(d) all of these

Ans: (d)

5. Killing of bacteria and disinfection is done in the ______ stage of waste disposal.

(a) first

(b) second

(c) third

(d) fifth

Ans: (c)