Use of chlorine in the treatment of sewage (A) Helps in grease separation (B) Increases the biological oxygen demand (BOD) (C) Causes bulking of activated sludge (D) Aids in flocculation

Use of chlorine in the treatment of sewage
(A) Helps in grease separation
(B) Increases the biological oxygen demand (BOD)
(C) Causes bulking of activated sludge
(D) Aids in flocculation
by

1 Answer

Answer :

(A) Helps in grease separation
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Related questions

Consider the following statements : Activated sludge process can be said to comprise : 1. Conversion of dissolved organic matter into biological flocs 2. Removal of dissolved BOD of the waste water 3. Digestion of the sludge Which of these statements are correct ? (a) 1, 2 and 3 (b) 1 and 2 only (c) 2 and 3 only (d) 1 and 3 only

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The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the (A) Bacterial stability factor (B) Relative stability (C) Biological oxygen demand (BOD) (D) Oxygen ion concentration

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Last Answer : (B) Relative stability

Drained sewage has biological oxygen demand `(BOD)`:

Description : Drained sewage has biological oxygen demand `(BOD)`:

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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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Measuring Biochemical Oxygen Demand (BOD) is a method used for (a) estimating the amount of organic matter in sewage water (b) working out the efficiency of oil driven automobile engines (c) measuring the activity of Saccharomyces cerevisiae in producing curd on a commercial scale (d) working out the efficiency of RBCs about their capacity to carry oxygen.

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Measuring Biochemical Oxygen Demand (BOD) is a method used for (a) estimating the amount of organic matter in sewage water (b) working out the efficiency of oil driven automobile engines (c) measuring the activity of Saccharomyces cerevisiae in producing curd on a commercial scale (d) working out the efficiency of RBCs about their capacity to carry oxygen.

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Last Answer : (a) estimating the amount of organic matter in sewage water

Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receiving effluents from (a) domestic sewage (b) dairy industry (c) petroleum industry (d) sugar industry.

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Biochemical Oxygen Demand (BOD) of sewage is the (a) Oxygen required to oxidise (b) Oxygen required to oxidise biologically inactive organic matter* (c) a and b both (d) none of these

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BOD (biological oxygen demand) is

Description : BOD (biological oxygen demand) is

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Biological oxygen demand (BOD) is a measure of

Description : Biological oxygen demand (BOD) is a measure of

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Last Answer : Ans: A

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BOD stands for : (1) Biological oxidation demand (2) Biological oxygen demand (3) Biochemical oxygen demand (4) Biotic oxidation demand

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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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Which of the following operational problems relate to the functioning of rapid gravity filter ? 1. Inadequate media comprising filter bed 2. Sludge bulking 3. Mud balls 4. Negative head 5. Incrustation of media (a) 1, 3, 4 and 5 only (b) 1, 2, 3 and 4 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4 and 5

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Primary treatment of sewage consists of removal of A. Large suspended organic solids B. Oil and grease C. Sand and girt D. Floating materials

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During preliminary treatment of a sewage A. Oil and grease are removed from skimming tanks B. Floating materials are removed by screening C. Girt and sand are removed by girt chambers D. All the above

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