How can one determine if a particular solid can be fluidized as in a fluidized bed?

How can one determine if a particular solid can be fluidized as in a fluidized bed?
by

1 Answer

Answer :

Mr. Alex C. Hoffmann of the Stratingh Institute for Chemistry and Chemical Engineering states:  “Whether a material can be fluidized at all is the question: if it is fine or sticky, the bed will be cohesive.  It will then tend to form channels through which the aeration gas will escape rather than being  dispersed through the interstices supporting the particles. In the other extreme: if the particles are too
large and heavy the bed will not fluidize well either, but tend to be very turbulent and form a spout.” He  goes on to present classification of fluidization by Geldart by use of the chart shown below. On this  chart, the x-axis is the average particle diameter and the y-axis is the bulk density of the bed.
by

Related questions

State Some Advantages Of Fluidized Bed Boilers?

Description : State Some Advantages Of Fluidized Bed Boilers?

Last Answer :  Any type of fuel solid, liquid (or) gaseous fuel (or) domestic and industrial waste can be used in FBC system. Any type of combustible matter can be burned by adjusting the factors as size ... .  High combustion efficiency.  The solid fuel need not be pulverized in fluidized bed boilers.

Write About Fluidized Bed Boilers?

Description : Write About Fluidized Bed Boilers?

Last Answer : When the high velocity gas is passed through a packed bed of finely divided solid particles, the particles become suspended in the gas stream and the packed bed becomes a fluidized bed. When ... Bed Combustion. The boiler plant using this fluidized bed combustion is known as fluidized bed boilers.

Draw the labelled diagram of “Fluidized bed dryer” and state its disadvantages.

Description : Draw the labelled diagram of “Fluidized bed dryer” and state its disadvantages.

Last Answer : Fluidized bed dryer. Disadvantages:   1) Production of fines 2) Generation of electrostatics charges amongst the particles  3) Contamination due to erosion of pipes and vessels due to abrasion by particles.

Give any two application of fluidized bed dryer.

Description : Give any two application of fluidized bed dryer.

Last Answer : i. It gives high drying rate.  ii. Suitable for thermolabile material.  iii. Drying takes place of individual particles.  iv. Temperature can be controlled.  v. Prevent the risk of migration of soluble material.  vi. It can mostly used for drying of granules.

Write short note on i. Cyclone separator. ii. Fluidized bed dryer.

Description : Write short note on i. Cyclone separator. ii. Fluidized bed dryer. 

Last Answer : Cyclone Separator Principle: Centrifugal force Construction1) Cyclone separator is size separation device 2) It consists of a cylindrical vessel with a conical base. 3) The upper part of ... are produced 3) High friction between practices generate electrostatic charges. Diagram:  

Give principle, working and use of fluidized bed drier.

Description : Give principle, working and use of fluidized bed drier. 

Last Answer : Principle: If a gas is allowed to flow upward through a bed of solid particle at a velocity greater than the settling velocity of the particle, particle partially suspended in the gas stream. The ... process for tablet preparation It is used in coating. Used for drying of filter cake.

The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

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

A trickle bed reactor is the one, which (A) Has altogether three streams either entering or leaving (B) Processes three reactants at different flow rates (C) Processes three reactants with same flow rate (D) Employs all the three phases (i.e. solid, liquid and gas)

Description : A trickle bed reactor is the one, which (A) Has altogether three streams either entering or leaving (B) Processes three reactants at different flow rates (C) Processes three reactants with same flow rate (D) Employs all the three phases (i.e. solid, liquid and gas)

Last Answer : (D) Employs all the three phases (i.e. solid, liquid and gas)

For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor. (A) Fixed (B) Fluidised bed reactor followed by a fixed (C) Fixed bed reactor followed by a fluidised (D) Fluidised

Description : For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor. (A) Fixed (B) Fluidised bed reactor followed by a fixed (C) Fixed bed reactor followed by a fluidised (D) Fluidised

Last Answer : (B) Fluidised bed reactor followed by a fixed

BET apparatus is used to determine the (A) Specific surface of a porous catalyst (B) Pore size distribution (C) Pore diameter (D) Porosity of the catalyst bed

Description : BET apparatus is used to determine the (A) Specific surface of a porous catalyst (B) Pore size distribution (C) Pore diameter (D) Porosity of the catalyst bed

Last Answer : (A) Specific surface of a porous catalyst

Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates is not used to derive BET equation? (A) Langmuir's assumption applies to every adsorbed layer (B) There is no dynamic equilibrium between successive layer (C) The adsorbed layer may be polymolecular in thickness and the heat of adsorption in each layer (except the first one) is involved in each of the evaporation process (D) None of these

Description : Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates ... (except the first one) is involved in each of the evaporation process (D) None of these

Last Answer : (B) There is no dynamic equilibrium between successive layer

Helium-mercury method can be used to determine the __________ of the catalyst particle. (A) Pore volume (B) Solid density (C) Porosity (D) All (A), (B), & (C)

Description : Helium-mercury method can be used to determine the __________ of the catalyst particle. (A) Pore volume (B) Solid density (C) Porosity (D) All (A), (B), & (C)

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

. B.E.T. method can be used to determine the __________ of a porous catalyst. (A) Solid density (B) Pore volume (C) Surface area (D) All (A), (B) and (C)

Description : . B.E.T. method can be used to determine the __________ of a porous catalyst. (A) Solid density (B) Pore volume (C) Surface area (D) All (A), (B) and (C)

Last Answer : (C) Surface area

How can one determine the particle size distribution for a given bulk solid?

Description : How can one determine the particle size distribution for a given bulk solid?

Last Answer : While there are high-tech methods of performing such an analysis (laser-diffraction and video imaging system are available), the simplest way is to use a sieve stack. For example, to analyze a ... a combination of movements (shaken) to allow the solids to pass through the appropriate mesh sizes.

Ladies... when you sleep with a man, is there a particular side of the bed that you absolutely insist upon taking?

Description : Ladies... when you sleep with a man, is there a particular side of the bed that you absolutely insist upon taking?

Last Answer : No, I have to be near the door. I have no explanation for this, just the need to be near it.

What is represented by the solid dots within components 'B' and 'C' of the diagram shown in the illustration? (See illustration EL-0081) EL-0081 A. The fact that these parts are subject to wear and replacement. B. An indication that they are for 110 volt AC operation only. C. The particular components contain a gas such as neon or argon. D. All of the above.

Description : What is represented by the solid dots within components 'B' and 'C' of the diagram shown in the illustration? (See illustration EL-0081) EL-0081 A. The fact that these parts are subject to wear and ... only. C. The particular components contain a gas such as neon or argon. D. All of the above.

Last Answer : Answer: C

Which of the following techniques may be performed quantitatively to determine the number of bacteria of a particular type? A.Pour plate B.Spread plate C.Both (a) and (b) D.Streak plate technique

Description : Which of the following techniques may be performed quantitatively to determine the number of bacteria of a particular type? A.Pour plate B.Spread plate C.Both (a) and (b) D.Streak plate technique

Last Answer : C.Both (a) and (b)

Which of the following algorithm is used by Google to determine the importance of a particular page? a) SVD b) PageRank c) FastMap d) All of the mentioned

Description : Which of the following algorithm is used by Google to determine the importance of a particular page? a) SVD b) PageRank c) FastMap d) All of the mentioned

Last Answer : PageRank

Point out the correct statement. a) The cloud service model you choose does not determine the variety of security features, compliance auditing, and other requirements b) To determine the particular security mechanisms you need, you must perform a mapping of the particular cloud service model to the particular application you are deploying c) A security control model includes the security that you normally use for your applications only CSE-R17.BLOGSPOT.COM d) All of the mentioned

Description : Point out the correct statement. a) The cloud service model you choose does not determine the variety of security features, compliance auditing, and other requirements b) To determine the particular ... you normally use for your applications only CSE-R17.BLOGSPOT.COM d) All of the mentioned

Last Answer : To determine the particular security mechanisms you need, you must perform a mapping of the particular cloud service model to the particular application you are deploying

Which of the following algorithm is used by Google to determine the importance of a particular page? a) SVD b) PageRank c) FastMap d) All of the mentioned

Description : Which of the following algorithm is used by Google to determine the importance of a particular page? a) SVD b) PageRank c) FastMap d) All of the mentioned

Last Answer : PageRank

“Composite sleeper index” is employed to determine a) sleeper density requirement b) number of fixtures required for a particular type of sleeper c) durability of sleeper d) mechanical strength of wooden sleepers and thereby gives its suitability as to be used as li sleepers.*

Description : “Composite sleeper index” is employed to determine a) sleeper density requirement b) number of fixtures required for a particular type of sleeper c) durability of sleeper d) mechanical strength of wooden sleepers and thereby gives its suitability as to be used as li sleepers.*

Last Answer : d) mechanical strength of wooden sleepers and thereby gives its suitability as to be used as li sleepers.*

Moral philosophies: A)are concerned with maximising the greatest good for the greatest number of people. B)are principles or rules that individuals use to determine what is right or wrong C)focus on the intentions associated with a particular behaviour and on the rights of the individual.

Description : Moral philosophies: A)are concerned with maximising the greatest good for the greatest number of people. B)are principles or rules that individuals use to determine what is right or wrong C)focus on the intentions associated with a particular behaviour and on the rights of the individual.

Last Answer : B)are principles or rules that individuals use to determine what is right or wrong

Moral philosophies A)are concerned with maximising the greatest good for the greatest number of people. B)are principles or rules that individuals use to determine what is right or wrong. C)focus on the intentions associated with a particular behaviour and on the rights of the individual. D)remain consistent in both work and family situations.

Description : Moral philosophies A)are concerned with maximising the greatest good for the greatest number of people. B)are principles or rules that individuals use to determine what is right or wrong. C)focus on ... and on the rights of the individual. D)remain consistent in both work and family situations.

Last Answer : B)are principles or rules that individuals use to determine what is right or wrong.

Suppose marketers at Lever Brothers are trying to determine whether the use of money off coupons for detergent was the reason for a sales increase in a particular store. The type of study conducted to answer this question would be: A)exploratory B)descriptive C)casual D)qualitative

Description : Suppose marketers at Lever Brothers are trying to determine whether the use of money off coupons for detergent was the reason for a sales increase in a particular store. The type of study conducted to answer this question would be: A)exploratory B)descriptive C)casual D)qualitative

Last Answer : C)casual

The histogram above represents the lifespan of a random sample of a particular type of insect. Determine the relationship between the mean and median. a. mean = median b. mean ≈ median c. mean < median d. mean > median

Description : The histogram above represents the lifespan of a random sample of a particular type of insect. Determine the relationship between the mean and median. a. mean = median b. mean ≈ median c. mean < median d. mean > median

Last Answer : d. mean > median

What will determine if the substance is a solid liquid or gas at 100 degrees?

Description : What will determine if the substance is a solid liquid or gas at 100 degrees?

Last Answer : What is the answer ?

How could you determine the specific heat of a sample of a solid substance that does not react with water?

Description : How could you determine the specific heat of a sample of a solid substance that does not react with water?

Last Answer : What is the answer ?