Filter aids like asbestos, kieselguhr, diatomaceous earth etc. are used to
increase the porosity of the final filter cake & reducing the cake resistance
during filtration. Filter aid is
(A) Added to the feed slurry
(B) Pre-coated on the filter medium prior to filtration
(C) Separated from the cake by dissolving solids or by burning it off
(D) All 'a', 'b' & 'c'

1 Answer

Answer :

(D) All 'a', 'b' & 'c'

Related questions

Description : Addition of filter aid to the slurry before filtration is done to __________ of the cake. (A) Increase the porosity (B) Increase the compressibility co-efficient (C) Decrease the porosity (D) Decrease the compressibility co-efficient

Last Answer : (A) Increase the porosity

Description : . In filtration, the use of 'filter aid' helps in (A) Reducing the filtration pressure (B) Accelerating the rate of filtration (C) Deplugging the filter medium (D) Enhancing the cake porosity in case of a dense impermeable cake

Last Answer : (C) Deplugging the filter medium

Description : During filtration operation, the filtrate encounters the resistance of the (A) Filter medium (B) Cake (C) Channel carrying the slurry to the upstream side of the cake and filtrate away from the filter medium (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : Filtration capacity of a rotary drum vacuum filter depends upon the (A) Cake thickness (B) Characteristics of the feed slurry (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : Filter aid is used to (A) Increase the rate of filtration (B) Decrease the pressure drop (C) Increase the porosity of the cake (D) Act as a support base for the septum

Last Answer : (C) Increase the porosity of the cake

Description : Which of the following is not used as filter aid? (A) Asbestos (B) Diatomaceous earth (C) Purified wood cellulose (D) Rice husk

Last Answer : (D) Rice husk

Description : Diatomaceous earth is a/an (A) Explosive (B) Filter aid (C) Filter medium (D) Catalyst

Last Answer : (B) Filter aid

Description : Filter medium resistance is important during the __________ of filtration. (A) Early stages (B) Final stages (C) Entire process (D) None of these

Last Answer : (A) Early stages

Description : Air filtration typically uses a filter. a. HEPA b. Membrane c. Sand d. Diatomaceous Earth

Last Answer : a. HEPA

Description : The most common filter aid is (A) Diatomaceous earth (B) Calcium silicate (C) Sodium carbonate (D) Silica gel

Last Answer : (A) Diatomaceous earth

Description : __________ is the most commonly used 'filter aid'. (A) Diatomaceous earth (B) Fuller's earth (C) Vermiculite (D) Semi-plastic clay

Last Answer : (A) Diatomaceous earth

Description : Which one is a filter aid? (A) Canvas fabric (B) Diatomaceous earth (C) Calcined lime (D) None of these

Last Answer : (B) Diatomaceous earth

Description : A compressible cake has the (A) Maximum porosity at the upstream side (B) Maximum porosity at the filter medium (C) Same porosity throughout the cake thickness (D) None of these

Last Answer : (A) Maximum porosity at the upstream side

Description : The porosity of a compressible cake is (A) Minimum at the filter medium (B) Minimum at the upstream face (C) Maximum at the filter medium (D) Same throughout the thickness of cake

Last Answer : (A) Minimum at the filter medium

Description : Filtration rate through a filter cake is proportional to (where, S = filtering surface R = specific cake resistance μ = viscosity of the filtrate) (A) S (B) 1/R (C) 1/μ (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

Description : The cake resistance increases steadily with the time of filtration in a plate and frame filter employing constant __________ filtration. (A) Rate (B) Pressure (C) Both (A) & (B) (D) Neither (A) nor (B

Last Answer : (C) Both (A) & (B)

Description : Define ‘slurry’ and ‘filter cake’.

Last Answer : i) Slurry: Mixture of insoluble substances suspended in a liquid and intended to filter before use.   ii) Filter cake: The solid which gets collected on the filter is called as filter cake.

Description : Filtration should be stopped in a filter press, if the (A) Cake becomes very dense (B) Liquor stops flowing out to the discharge (C) Filtration pressure rises suddenly (D) Both (B) & (C

Last Answer : (D) Both (B) & (C

Description : During the washing of cake (A) All the resistances are constant (B) Filter medium resistance increases (C) Filter medium resistance decreases (D) Cake resistance decreases

Last Answer : (A) All the resistances are constant

Description : Benzoic acid and diphenyl ketone are both solids insoluble in water. A mixture of these compounds can be separated if we (a) add the mixture to a solution of NaOH in water, and filter. (b) add ... benzene. (d) It is impossible to separate a mixture of two solids when both are insoluble in water.

Last Answer : add the mixture to a solution of NaOH in water, and filter

Description : Filtration operation carried out by continuous increase of the inlet pressure of slurry, is called the __________ filtration. (A) Constant rate (B) Varying pressure (C) Varying rate (D) Constant pressure

Last Answer : (A) Constant rate

Description : The controlling resistance in a rotary drum vacuum filter is the __________ resistance. (A) Piping (B) Cake (C) Filter medium (D) None of these

Last Answer : (B) Cake

Description : Filtrate flow rate in case of a rotary drum vacuum filter (in which Rm < < Rc ) is proportional to __________ and the cycle time (where, μ = filtrate viscosity Rm = filter medium resistance Rc = cake resistance). (A) √μ (B) 1/√μ (C) 1/μ (D) 1/μ

Last Answer : (B) 1/√μ

Description : Which adsorbent is used for removing sulphur compounds (S Q, H2S, RSH etc.) removal from coke oven gas in by-products recovery plant? (A) Silica gel (B) Diatomaceous earth (C) Basalt (D) Bog iron (i.e., moist ferric hydroxide)

Last Answer : (D) Bog iron (i.e., moist ferric hydroxide)

Description : Filtration rate does not depend upon the (A) Pressure drop & area of filtering surface (B) Resistance of the cake & the septum (C) Properties of the cake & the filtrate (D) None of these

Last Answer : (D) None of these

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 : Write the qualities of an ideal filter aids. Give examples of filter aid.

Last Answer : Ideal qualities of filter aid: i. It should be remain suspended in the liquid. ii. It should be free from impurities. iii. It should be inert. iv. It should have a particle size distribution ... ii. Cellulose. iii. Carbon. iv. Diatomaceous earth (silica). v.Perlite. vi.Activated Charcoal

Description : Cake resistance is (A) Important in the beginning of filtration (B) Decreased with the time of filtration (C) Independent of pressure drop (D) None of these

Last Answer : (D) None of these

Description : Enlist the different filter medium used for filtration.

Last Answer : i) Filter paper. ii) Cotton wool. iii) Glass wool. iv) Asbestos. v) Fine muslin. vii)FilterMembranefilter. viii)Sintered glass filter. 

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 : Wet chlorine gas produced during electrolysis of brine is dehydrated by (A) Spraying 66° Be H2SO4 counter current to the flow of the gas (B) Passing it through a bed of diatomaceous earth (C) Passing it through a bed of silica gel (D) None of these

Last Answer : (A) Spraying 66° Be H2SO4 counter current to the flow of the gas

Description : Which of the following statements best describes the material known as varnished cambric? A. Felted asbestos sealed with varnish. B. Cotton cloth coated with insulating varnish. C. Rubber ... Paper impregnated with mineral oil, specially wrapped with nonmetallic tape, and coated with varnish.

Last Answer : Answer: B

Description : __________ is used for producing a thick suspension from a thin slurry. (A) Cartridge filter (B) Rotary drum vacuum filter (C) Pressure filter thickener (D) Plate and frame filter press

Last Answer : (C) Pressure filter thickener

Description : Introduction of slurry in a plate and frame filter press is done through a plate in each frame. The plate of this filter has a __________ surface. (A) Plane (B) Curved (C) Ribbed (D) Either (A) or (B)

Last Answer : (C) Ribbed

Description : Percentage of drum submerged in the slurry in case of rotary drum filter is (A) 3 (B) 30 (C) 85 (D) 25

Last Answer : (B) 30

Description : When welding medium carbon steel plates over 100mm in thickness would the basic electrodes require any pre treatment before use? a) None if they were in a vacuum pack opened 8 hours prior to use b) None if ... ) Heat to 500 °C for 2 hours if used outside d) Baked at 150°C for 4hours prior to use

Last Answer : b) None if they were in a sealed vacuum pack prior to use

Description : Catalyst used in the catalytic polymerisation is (A) Phosphoric acid on kieselguhr (B) Aluminium chloride (C) Nickel (D) Vanadium pentoxide

Last Answer : (A) Phosphoric acid on kieselguhr

Description : Prior to using an analog type ohmmeter, the leads are purposely shorted together. Which of the following actions should be taken if, when adjusting to 'zero' ohms, the indicating needle can not be ... be added to each final reading. D. The test reading should be subtracted from each final reading.

Last Answer : Answer: B

Description : Conditioners like finely divided peat are added to the fertiliser to (A) Counteract burning (B) Avoid caking & hardening (C) Produce bulk (D) Increase its solubility

Last Answer : (B) Avoid caking & hardening

Description : Detergents dissolved in water help in cleaning clothes by A. Increasing the temperature of water B. Reacting chemically with dirt C. Reducing the surface tension of water D. Dissolving dirt

Last Answer : ANSWER: C

Description : Detergents dissolved in water help in cleaning clothes by-----? A. Increasing the temperature of water B. Reacting chemically with dirt C. Reducing the surface tension of water (Answer) D. Dissolving dirt

Last Answer : C. Reducing the surface tension of water (Answer)

Description : With increase in drum speed, in a rotary drum filter, the filtration rate (A) Increases (B) Increases linearly (C) Decreases (D) Is not affected

Last Answer : (A) Increases

Description : A soil mass coated with a thin layer of paraffin weighs 460 g. When immersed, it displaces 299 cc of water. The weight of paraffin is 10 g. If specific gravity of solids is 2.5 and that of paraffin 0.9, the void ratio of soil, is (A) 0.55 (B) 0.60 (C) 0.65 (D) 0.70

Last Answer : Answer: Option B

Description : If dry density, water density and specific gravity of solids of a given soil sample are 1.6 g/cc, 1.84 g/cc and 2.56 respectively, the porosity of the soil sample, is (A) 0.375 (B) 0.370 (C) 0.380 (D) 0.390

Last Answer : (A) 0.375

Description : The ratio of the weight of given volume of soil solids to the weight of an equal volume of distilled water at the given temperature, is known (A) Porosity (B) Specific gravity (C) Void ratio (D) Water content

Last Answer : (B) Specific gravity

Description : The ratio of the volume of voids to the volume of soil solids in a given soil mass, is known (A) Porosity (B) Specific gravity (C) Void ratio (D) Water content

Last Answer : (C) Void ratio

Description : If the volume of voids is equal to the volume of solids in a soil mass, then the values of porosity and voids ratio respectively are (A) 1.0 and 0.0 (B) 0.0 and 1.0 (C) 0.5 and 1.0 (D) 1.0 and 0.5

Last Answer : (C) 0.5 and 1.0

Description : The ratio of the weight of water to the weight of solids in a given mass of soil, is known (A) Porosity (B) Specific gravity (C) Void ratio (D) Water content

Last Answer : Answer: Option D

Description : Shell and leaf filter as compared to plate and frame filter (A) Entails less labor cost (B) Facilitates filtration under higher pressure (C) Provides more effective washing (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)