Particle Characteristics

Question 1

Surface Area Shape Factor

Answer 1

fs = A/ L^2

fs > pi as sphere has minimum surface area

Question 2

Volume Shape Factor

Answer 2

fv = V/L^3

fv > pi/6

Question 3

Specific Shape factor

Answer 3

F = fs/fv

Question 4

Sphericity

Answer 4

Psi = A_sphere/A_eq.vol

Psi < 1 for all non spherical particles

Question 5

Specific Surface

Answer 5

Sp = A/V

Question 6

Envelope Density

Answer 6

ro_e = m/Vt

Mass/ Total Volume

Question 7

Skeletal Density

Answer 7

ro_s = m/Vs

Mass / Solid Volume

Question 8

Envelope Density vs Skeletal Density

Answer 8

ro_e < ro_s

as Vt > Vs

Question 9

Porosity

Answer 9

Eps = Vv/Vt = (Vt - Vs)/Vt = 1 - (ro_e/ro_s)

Question 10

Particle size measurement methods by particle classification

Answer 10

• Sieve Analysis

- Air Classification

Question 11

Particle size measurement methods by particle counting

Answer 11

• Image analysis (dry)

- Flow cytometry (wet)

Question 12

Particle size measurement methods by phenomena based measurements

Answer 12

• Sedimentation Velocity

- Laser Diffraction

Question 13

BET Adsorption equation

Answer 13

(p/p0)/(V(1 - p/p0)) = 1/(VmC) + (p/p0)(C - 1)/(VmC)