Description : Why sedimentation tanks help to remove solid wastes in the treatment of waste water?
Last Answer : Need answer
Description : How does sedimentation tanks help to remove soid wastes in the treatment of waste water?
Last Answer : Feel Free to Answer
Description : Coal washing waste water containing about 3% suspended solids (comprising of clay, slate, stone etc.) is treated for solid particles removal (A) By chemical coagulation (B) In sedimentation tanks equipped with mechanical scrapper (C) In vacuum filter (D) In clarifiers
Last Answer : (B) In sedimentation tanks equipped with mechanical scrapper
Description : 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
Last Answer : ANS: B
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
Description : Which is the most practical and economical method for removal of suspended solid matter from polluted water? (A) Sedimentation (B) Skimming off (C) Chlorination (D) Biological oxidation
Last Answer : (A) Sedimentation
Description : The normal values of over flow rates for secondary 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 10,000 litres/sqm/day
Last Answer : ANS: A
Description : The maximum depth of sedimentation tanks, is kept A. 3 m B. 3.5 m C. 4 m D. 4.5 m
Description : Pick up the incorrect statement from the following: A. Septic tanks are horizontal continuous flow type of sedimentation tanks B. Septic tanks are generally provided a detention period of 12 to 36 hours C ... covered and high vent shafts are provided for the escape of foul gases D. None of these
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
Description : The detention period for plain sedimentation water tanks, is usually A. 4 to 8 hours B. 8 to 16 hours C. 16 to 24 hours D. 24 to 36 hours
Description : 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
Description : The normal values of over flow rates for sedimentation tanks using coagulant, 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
Last Answer : ANS: C
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
Description : Normal values of overflow rate for sedimentation tanks using coagulants in litres/hr/m2 , generally range between (A) 250 to 500 (B) 500 to 750 (C) 750 to 1000 (D) 1000 to 1250
Last Answer : (D) 1000 to 1250
Description : 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 ... in sedimentation tanks, is generally limited to 0.3 m/minute (D) All the above
Last Answer : (D) All the above
Description : In plain sedimentation tanks under normal conditions, impurities are removed upto (A) 60 % (B) 70 % (C) 80 % (D) 90 %
Last Answer : (B) 70 %
Description : Normal values of overflow rate for plain sedimentation tanks in litres/hr/m2 , generally range between (A) 100 to 250 (B) 250 to 500 (C) 500 to 750 (D) 750 to 1000
Last Answer : (C) 500 to 750
Description : The maximum depth of sedimentation tanks is limited to (A) 2 m (B) 3 m (C) 5 m (D) 6 m
Last Answer : (D) 6 m
Description : Flow through period, in sedimentation tanks, is (A) Equal to detention period (B) More than detention period (C) Less than detention period (D) Detention period divided by displacement efficiency
Last Answer : (C) Less than detention period
Description : The detention period for plain sedimentation water tanks, is usually (A) 4 to 8 hours (B) 8 to 16 hours (C) 16 to 24 hours (D) 24 to 36 hours
Last Answer : (D) 24 to 36 hours
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)
Description : Solid particles separation based on the difference in their flow velocities through fluids is termed as the (A) Clarification (B) Classification (C) Elutriation (D) Sedimentation
Last Answer : (B) Classification
Description : Separation of a suspension or slurry into a supernatant clear liquid (free from particles) and a thick sludge containing a high concentration of solid is called (A) Classification (B) Sedimentation (C) Clarification (D) Decantation
Last Answer : (B) Sedimentation
Description : Separation of solid suspended in liquid into a supernatant clear liquid and a denser slurry employs a process termed as the (A) Coagulation (B) Flocculation (C) Sedimentation (D) Clarification
Last Answer : (C) Sedimentation
Description : In the context of the chemical process industries, the term BOD is normally associated with the (A) Characterisation of solid wastes (B) Organic concentration in gaseous effluents (C) Characterisation of liquid effluents (D) Characterisation of boiler feed water
Last Answer : (C) Characterisation of liquid effluents
Description : What are the methods of treatment & disposal of radioactive wastes? (A) Evaporation & chemical precipitation (B) Biological methods & adsorption in ion exchange materials (C) Fixing into a solid mass with cement and sinking deep in the sea (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : Radioactive solid nuclear wastes are disposed off by (A) High temperature incineration (B) Pathological incineration (C) Pyrolysis (D) Underground burial in concrete containers
Last Answer : (D) Underground burial in concrete containers
Description : 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
Last Answer : (D) Chemical coagulation
Description : 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
Last Answer : (4) Remove suspended solids Explanation: The function of sedimentation tank in the sewage treatment is to remove suspended solids.
Description : 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 ... of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation
Last Answer : (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation
Description : To remove very fine suspended particles from water, the method adopted is (A) Screening (B) Sedimentation (C) Boiling (D) Filtration
Last Answer : To remove very fine suspended particles from water, the method adopted is (A) Screening (B) Sedimentation (C) Boiling (D) Filtration
Last Answer : Remove suspended solids
Description : Pick out the correct statement. (A) Chemical oxygen demand (COD) is a measure of chemically oxidisable organic matter present in water (B) COD is determined by oxidising the organic matter present in water with potassium dichromate ... of potable water may be 1-2 mg/litre (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : What organs filter the blood and remove wastes?
Last Answer : Kidneys filter blood and remove waste.
Description : which one of the following is not a function of Artificial Kidney? (a) To remove nitrogenous wastes from the blood. (b) To remove excess fluids from the blood. (c) To reabsorb essential nutrients from the blood. (d) To filter and purify the blood.
Last Answer : (c) To reabsorb essential nutrients from the blood.
Description : Gravity settling tanks/porous filters are used to remove particles larger than
Last Answer : Gravity settling tanks/porous filters are used to remove particles larger than A. `2 mum ` B. `50 mum` C. `20 mum` D. `10 mum`
Description : Skimming tanks are A. Used to remove the grease and oil B. Those from which sludge is skimmed out C. Tanks provided with self- cleansing screens D. Improved version of grit chambers
Description : What is the particle model of matter and how does it explain the changes of state that occur with variations in temperature or pressure?
Description : Of all of the current material addition rapid prototyping technologies, which one is the mostwidely used? a.Ballistic particle manufacturing b.Selective laser sintering c.Solid ground curing d.Stereolithography
Last Answer : d.Stereolithography
Description : Pick out the wrong statement. (A) Gape is the greatest distance between the crushing surfaces or the jaws (B) The angle of nip (2α) is the angle between roll faces at the level where they will ... Reduction ratio is the ratio of the maximum size of the particles in the feed to that in the product
Last Answer : (C) Crushing efficiency is the ratio of the energy absorbed by the solid to the surfaces energy created by crushing
Description : The sphericity of a solid particle of cubical shape is (A) π (B) (π/6) 1/3 (C) (π/6) 1/2 (D) π/3
Last Answer : (B) (π/6) 1/3 (C) (π/6) 1/2
Description : Number of particles in a crushed solid sample is given by (where, m = mass of particles in a sample, Vp = volume of one particle, ρ= density of particles) (A) m/ρ . Vp (B) m . ρ/Vp (C) m . Vp /ρ (D) Vp /m . ρ
Last Answer : (A) m/ρ . Vp
Description : The rate of solid-liquid extraction is limited by the (A) Phase change of the solute as it dissolves in the solvent (B) Diffusion of the solute through the solvent in the pores to the outside of the particle (C) ... contact with the particle to the main bulk of the solution (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : In Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the __________ of its diameter. (A) Inverse (B) Square root (C) Second power (D) First power
Last Answer : (B) Square root
Description : In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. (A) Directly proportional to (B) Inversely proportional to (C) Inversely proportional to the square root of (D) Independent of
Last Answer : (B) Inversely proportional to
Description : The terminal velocity of a solid spherical particle falling through a stationary fluid mass in the Stoke's law range is proportional to the (A) Inverse of fluid viscosity (B) Square of particle size (C) Difference in the densities of the particle & fluid (D) All (A), (B) and (C)
Description : Which of the following is not an advantage of fluidisation from transferoperation point of view? (A) Intimate contact of the fluid with all parts of the solid particles (B) Lower fluid pumping power requirement (C) Minimisation of temperature variation (D) Prevention of particle segregation
Last Answer : (B) Lower fluid pumping power requirement
Description : The main factor on which the behaviour of a mass of fluidised solid depends mainly is the (A) Fluid characteristics (B) Particle size (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)