Pick up the correct statement from the following: 

(A) Detention period for plain sedimentation tanks ranges between 4 to 8 hours 

(B) Detention period for sedimentation tanks, using coagulants usually ranges between 2 to 4 

hours 

(C) The horizontally flow velocity in sedimentation tanks, is generally limited to 0.3 m/minute 

(D) All the above

1 Answer

Answer :

(D) All the above

Related questions

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Last Answer : (D) 24 to 36 hours

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Description : For a continuous flow type of sedimentation tanks A. Width of the tank is normally kept about 6 m B. Length of the tank is normally kept 4 to 5 times the width C. Maximum horizontal flow velocity is limited to 0.3 m/minute D. All the above

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Description : The normal value of over flow rates for plain primary sedimentation tanks, ranges between A. 25,000 to 35,000 litres/sqm/day B. 40,000 to 50,000 litres/sqm/day C. 50,000 to 60,000 litres/sqm/day D. 80,000 to 100,000 litres/sqm/day

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Last Answer : ANS: C

Description : The efficiency of sedimentation tank does not depend upon  (A) Depth of tank  (B) Length of tank  (C) Detention period  (D) Velocity of water

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Description : For a grit chamber, if the recommended velocity of flow is 0.2 m/sec and detention period is 2 minutes, the length of the tank, is A. 16 m B. 20 m C. 24 m D. 30 m

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