Cow-dung and water are mixed in equal proportions in the mixing tank M to prepare the slurry. It takes about 50 to 60 days for the new gas-plant to become operative (start functioning).The spent dung-slurry, left after the extraction of biogas, is rich in nitrogen and phosphorus compounds and hence forms a good manure.
1. Slurry is a mixture of cow dung and water.
a. TRUE
b. FALSE
2. Mixture of cow dung and water in equal proportions prepare ..........
a. Mud
b. Slurry
c. Cow dung cakes
d. None of these
4. A new biogas plant becomes operative in ............ days.
a. 30 - 40
b. 40 - 50
c. 50 - 60
d. 60 - 70
4. The spent dung-slurry left after the extraction of biogas in rich in
a. Nitrogen and phosphorus
b. Oxygen and calcium
c. Sulphur and calcium
d. Hydrogen and nitrogen
5. Mostly we use ............ in biogas plants.
a. Human excreta
b. Cow dung
c. Plant waste
d. None of these
