In a sludge tank, the gas mainly produced, is_________________?

Related Mcqs:

1. The moisture content of sludge is reduced from 90% to 80% in a sludge digestion tank. The percentage decrease in the volume of sludge, is_______________?

   A. 25 % B. 50 % C. 10 % D. 5 %...

2. In a sludge digestion tank if the moisture content of sludge V1 litres is reduced from p1 % to p2 % the volume V2 is____________________?

   A. [(100 + P1)/(100 – P2)] V1 B. [(100 – P1)/(100 + P2)] V1 C. [(100 – P1)/(100 – P2)] V1 D. [(100 + P2)/(100 – P1)] V1...

3. The settling velocity of the particles larger than 0.06 mm in a settling tank of depth 2.4 is 0.33 m per sec. The detention period recommended for the tank, is____________________?

   A. 30 minutes B. 1 hour C. 1 hour and 30 minutes D. 2 hours...

4. The effluent of a septic tank is_________________?

   A. Fit for discharge into any open drain B. Foul and contains dissolved and suspended solids C. As good as that from a complete treatment D. None of these...

5. The sludge does not contain waste water from_________________?

   A. Bath rooms B. Wash basins C. Kitchen sinks D. Toilets...

6. In normal conditions, the period for sludge digestion, is_______________?

   A. 10 days B. 20 days C. 30 days D. 60 days...

7. In the activated sludge process__________________?

   A. Aeration is continued till stability B. Aeration is done with an admixture of previously aerated sludge C. Sludge is activated by constant stirring D. Water is removed by centrifugal action...

8. The first stage of neutral process of sludge digestion, is__________________?

   A. Acid fermentation B. Acid regressio C. Alkaline fermentation D. None of these...

9. The digested sludge from septic tanks, is removed after a maximum period of__________________?

   A. 3 years B. 3.5 years C. 4 years D. 5 years...

10. The rate of accumulation of sludge per person per year, is_______________________?

    A. 10 litres B. 15 litres C. 20 litres D. 25 litres...