How dissolved oxygen control is achieved in feed water system?

How dissolved oxygen control is achieved in feed water system?
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1 Answer

Answer :

Hydrazine is added to feed water system to control dissolved oxygen.  
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For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than __________ ppm. (A) 10000 (B) 5 (C) 500 (D) 1000

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Hydrazine is used in water treatment for the removal of (A) Colloidal impurities (B) Dissolved oxygen (C) Turbidity (D) Chlorinous taste

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Chlorination of water does not remove (A) Ammonia content (B) B.O.D. (C) Organic matter content (D) Dissolved oxygen

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The best guide to judge the general quality of water is the measurement of its (A) pH value (B) Electrical conductivity (C) Turbidity (D) Dissolved oxygen content

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Which of the following is not a feature of potable water? a) It must be clean, colourless and odourless. b) It must be free from bacteria c) It must have excessive sodium ,calcium and magnesium d) It must contain dissolved oxygen and carbon dioxide

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Which of the following parameters is not used as a pollution indicator in water? (A) Total dissolved solids (B) Coliform count (C) Dissolved oxygen (D) Density

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Fuel economy in an industrial furnace operation cannot be achieved by the use of (A) Stoichiometric combustion air (B) Non-preheated combustion air (C) Combustion air not enriched with oxygen (D) Recuperators

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In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid fuels (C) Imperfect mixing of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace

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Last Answer : (C) Imperfect mixing of fuel & air and infiltration of air

Fuel economy in furnaces can be achieved by (A) Using oxygen enriched combustion air (B) Preheating the combustion air (C) Reducing the heat loss through furnace openings & doors (D) All (A), (B) and (C

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Higher furnace temperature cannot be achieved by use of a lean fuel gas in the furnace by (A) Increasing the draft in the furnace (B) Preheating the fuel gas (C) Oxygen enrichment of combustion air (D) Preheating the combustion air

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Which sensors are used to identify dissolved oxygen?

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What take oxygen during the lung respiration and oxygen gas is dissolved in the blood stream?

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Where is dissolved oxygen likely to be lowest?

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The optimum dissolved oxygen level (in mg/litre) required for survival of aquatic organisms is - (1) 4 - 6 (2) 2 - 4 (3) 8 - 10 (4) 12 - 16

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Commercial nitric acid is coloured because it contains dissolved – (1) Oxygen (2) Nitrous oxide (3) Nitrogen dioxide (4) Coloured impurities

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For the survival of fish in a river stream, the minimum dissolved oxygen is prescribed A. 3 ppm B. 4 ppm C. 5 ppm D. 10 ppm

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Last Answer : ANS: B

If a 2% solution of sewage sample is incubated for 5 days at 20°C and the dissolved oxygen depletion was found to be 8 mg/l. The BOD of the sewage is A. 100 mg/l B. 200 mg/l C. 300 mg/l D. 400 mg/l

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Last Answer : ANS: D

The amount of oxygen consumed by the aerobic bacterias which cause the aerobic biological decomposition of sewage, is known A. Bio-Chemical Oxygen Demand (B.O.D.) B. Dissolved Oxygen (D.O.) C. Chemical Oxygen Demand (C.O.D.) D. None of these

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Last Answer : ANS: B