During sewage treatment, the sewage is subjected to __________ treatment in Imhoff tank. (A) Filtration (B) Digestion (C) Sedimentation (D) Both (B) and (C)

During sewage treatment, the sewage is subjected to __________
treatment in Imhoff tank.
(A) Filtration
(B) Digestion
(C) Sedimentation
(D) Both (B) and (C)
by

1 Answer

Answer :

(D) Both (B) and (C)
by

Related questions

For treating the sewage of a large city, you will recommend A. A sedimentation tank and an activated sludge treatment plant B. A plant consisting of Imhoff tanks with low rate trickling filters C. Sedimentation tanks with high rate trickling filters D. None of these

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Last Answer : ANS: A

The sewage treatment units in which anaerobic decomposition of organic matter is used, are called A. Imhoff tanks B. Trickling filters C. Sludge sedimentation tanks D. None of these

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The main type of sludge gas evolved during sewage treatment in Imhoff tank is (A) CO2 (B) CH4 (C) CO (D) H2

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Last Answer : (B) CH4

A shallow pond in which the sewage is retained and biologically treated is called (A) Oxidation (B) Imhoff tank (C) Lagoon (D) Skimming tank

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During sewage treatment, effluent from which one of the following treatment units has minimum wt/vol amount of suspended solids? (a) Detritus channel (b) Primary sedimentation tank (c) Secondary sedimentation tank (d) Activated sludge process aeration tank

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The function of sedimentation tank in sewage treatment is to: (1) Disinfect the sewage (2) Remove water content (3) Aerate the sewage (4) Remove suspended solids

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Last Answer : (4) Remove suspended solids Explanation: The function of sedimentation tank in the sewage treatment is to remove suspended solids.

The function of sedimentation tank in sewage treatment is to: (1) Disinfect the sewage (2) Remove water content (3) Aerate the sewage (4) Remove suspended solids

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Last Answer : Remove suspended solids

Before discharging the foul sewage into rivers, it is generally treated by (a) screening (b) sedimentation (c) Oxidation (d) sludge digestion and disinfection (e) all the above*

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Last Answer : e) all the above*

During treatment of water, sedimentation is done (A) Before filtration (B) After filtration (C) Simultaneously with filtration (D) Along with chlorination

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Fine grit present in sewage is removed in the __________ during sewage treatment. (A) Grit chamber (B) Detritus tank (C) Trickling filter (D) Skimming tank

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In water treatment, alum [Al2 (SO4 )3 ] is used for the process of (A) Filtration (B) Coagulation (C) Sedimentation (D) Disinfection

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Last Answer : (B) Coagulation

Pick out the true statement pertaining to water treatment. (A) Slow sand filters can remove colour completely (B) Activated carbon can be used for taste & odour control without subsequent filtration (C) Application of activated carbon reduces the temporary hardness of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

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In sewage treatment, its sedimentation is speeded up by commonly adding (A) Hydrochloric acid (B) Lime (C) Copper sulphate (D) Sodium sulphate

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If Organic sources of carcinogenic compounds in water persist even after chlorination, then what is the correct sequence among treatment processes listed below if all these are considered compulsory ? 1. Coagulation 2. Sedimentation 3. Filtration in general 4. Activated carbon bed filtration 5. Flocculation 6. Chlorination a) 4-5-3-2-6 and 1 b) 1-2-3-4-5 and 6 c) 4- 2- 3- 1- 5 and 6 d) 1-5-2-3-4 and 6

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Last Answer : d) 1-5-2-3-4 and 6

The pH value of sewage is determined with the help of A. Imhoff Cone B. Turbid meter C. Potentiometer D. None of these

Description : The pH value of sewage is determined with the help of A. Imhoff Cone B. Turbid meter C. Potentiometer D. None of these

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The function of skimming tank in sewage treatment is to remove __________ substances. (A) Dissolved solid (B) Suspended solid (C) Oil & fatty (D) Gritty & inorganic

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In a sedimentation tank, the detention period for water ranges from __________ hours. (A) 2 to 4 (B) 8 to 12 (C) 16 to 20 (D) 24 to 32

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Last Answer : (A) 2 to 4

The process opposite to 'dispersion' is termed as the(A) Flocculation(B) Sedimentation(C) Filtration(D) None of these

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The most commonly used substance to speed up the sedimentation of sewage is (A) Lime (B) Sulphuric acid (C) Chlorine (D) Sodium bisulphite

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Why Filtration is a better method than simple sedimentation and decantation?

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Iodine can be separated from a mixture of Iodine and Potassium Chloride by - (1) Filtration (2) Sublimation (3) Distillation (4) Sedimentation

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Iodine can be separated from a mixture of Iodine and Potassium Chloride by – (1) sedimentation (2) filtration (3) sublimation (4) distillation

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The process of removing calcium and magnesium from hard water is known as – (1) Sedimentation (2) Filtration (3) Flocculation (4) Water softening

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The main process to purify water by filtration, is (A) Mechanical straining (B) Flocculation and sedimentation (C) Biological metabolism (D) All the above

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To remove very fine suspended particles from water, the method adopted is (A) Screening (B) Sedimentation (C) Boiling (D) Filtration

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The process of passing water through beds of granular materials, is called (A) Screening (B) Sedimentation (C) Filtration (D) None of these

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Iodine can be separated from a mixture of Iodine and Potassium Chloride by (1) sedimentation (2) filtration (3) sublimation (4) distillation

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Last Answer : sublimation

The process of removing calcium and magnesium from hard water is known as (1) Sedimentation (2) Filtration (3) Flocculation (4) Water softening

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The function of skimming tank in sewage treatment is to remove – (1) oil and fatty substances (2) suspended solids (3) gritty substances (4) inorganic substances

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The sewage discharge in a detritus tank of a treatment plant is 576 litres/sec with flow velocity of 0.2 m/sec. If the ratio of width to depth is 2, the depth is A. 100 cm B. 110 cm C. 120 cm D. 150 cm

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Last Answer : ANS: C

Indicate which of the statement is incorrect (a) The detritus tank is type of a grit chamber (b) In detritus tank, velocity of flow is further reduced (c) Grit chambers are provided in the sewage treatment process to remove the heavier inorganic matter as grit, sand etc. from the sewage (d) None of them*

Description : Indicate which of the statement is incorrect (a) The detritus tank is type of a grit chamber (b) In detritus tank, velocity of flow is further reduced (c) Grit chambers are provided in the sewage ... to remove the heavier inorganic matter as grit, sand etc. from the sewage (d) None of them*

Last Answer : (d) None of them*

The function of skimming tank in sewage treatment is to remove (1) oil and fatty substances (2) suspended solids (3) gritty substances (4) inorganic substances

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Before discharging the foul sewage into rivers, it is generally treated by A. Screening B. Sedimentation C. Oxidation D. All the above

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__________ substances present in sewage are removed in grit chamber during sewage treatment. (A) Organic (B) Fatty(C) Inorganic(D) Dissolved

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The type of bacteria which is active in trickling filter during biological treatment of sewage is the __________ bacteria. (A) Anaerobic (B) Saprophytic (C) Aerobic (D) Parasitic

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Gravity settling process is not involved in the working of a (A) Hydrocyclone (B) Classifier (C) Dorr-thickener (D) Sedimentation tank

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Which of the following is the most efficient for removal of very finely divided suspended solids and colloidal matter from the polluted waterstream?(A) Sedimentation tank(B) Circular clarifier(C) Mechanical flocculation(D) Chemical coagulation

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Removal of oil and grease from sewage, is known A. Screening B. Skimming C. Filtration D. None of these

Description : Removal of oil and grease from sewage, is known A. Screening B. Skimming C. Filtration D. None of these

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The ratio of design discharge to the surface area of a sedimentation tank is called A. Surface loading B. Overflow rate C. Overflow velocity D. All of these

Description : The ratio of design discharge to the surface area of a sedimentation tank is called A. Surface loading B. Overflow rate C. Overflow velocity D. All of these

Last Answer : ANS: D

The settlement of a particle in sedimentation tank, is affected by A. Velocity of flow B. Viscosity of water C. Size and shape of solid D. All the above

Description : The settlement of a particle in sedimentation tank, is affected by A. Velocity of flow B. Viscosity of water C. Size and shape of solid D. All the above

Last Answer : ANS: D

In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is A. Q/(B × D) B. Q/(L × D) C. Q/L D. Q/(B × L)

Description : In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is A. Q/(B × D) B. Q/(L × D) C. Q/L D. Q/(B × L)

Last Answer : ANS: D

The discharge per unit plan area of a sedimentation tank, is generally called A. Over flow rate B. Surface loading C. Over flow velocity D. All the above

Description : The discharge per unit plan area of a sedimentation tank, is generally called A. Over flow rate B. Surface loading C. Over flow velocity D. All the above

Last Answer : ANS: D

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

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

Last Answer : ANS: D

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

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

Last Answer : D

Normal values of overflow rate for plain sedimentation tank using coagulants, is (A) 750 to 1000 litres/hr/m2(B) 1000 to 1250 litres/hr/m2(C) 1250 to 1500 litres/hr/m2(D) 1500 litres/hr/m

Description : Normal values of overflow rate for plain sedimentation tank using coagulants, is (A) 750 to 1000 litres/hr/m2 (B) 1000 to 1250 litres/hr/m2 (C) 1250 to 1500 litres/hr/m2 (D) 1500 litres/hr/m

Last Answer : (B) 1000 to 1250 litres/hr/m2

Detention time for plain sedimentation tank usually ranges from (A) 2 to 4 hours (B) 4 to 8 hours (C) 6 to 10 hours (D) 8 to 12 hours

Description : Detention time for plain sedimentation tank usually ranges from (A) 2 to 4 hours (B) 4 to 8 hours (C) 6 to 10 hours (D) 8 to 12 hours

Last Answer : (B) 4 to 8 hours

The flow of water gets retarded, in (A) Settling tank (B) Sedimentation tank (C) Clarifier (D) All the above

Description : The flow of water gets retarded, in (A) Settling tank (B) Sedimentation tank (C) Clarifier (D) All the above

Last Answer : (D) All the above

Distribution of wash water is provided in (A) Sedimentation tank (B) Slow sand filter (C) Rapid gravity filter (D) All the above

Description : Distribution of wash water is provided in  (A) Sedimentation tank  (B) Slow sand filter  (C) Rapid gravity filter  (D) All the above 

Last Answer : (C) Rapid gravity filter

Velocity of flow of water in plain sedimentation water tank, is normally kept (A) 3 cm/minute (B) 10 cm/minute (C) 20 cm/minute (D) 30 cm/minute

Description : Velocity of flow of water in plain sedimentation water tank, is normally kept  (A) 3 cm/minute  (B) 10 cm/minute  (C) 20 cm/minute  (D) 30 cm/minute 

Last Answer : (D) 30 cm/minute 

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

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

Last Answer : (D) Velocity of water