Related to particle engineering

1. Particle Technology
(ChE-203)
Lecture No. 26
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2. Chapter 28
• Calculate Ni for individual fractions
• This Nw equation gives total number of particles
• Use the value of a=2 and ρp = 0.00265
• Using table 28.2 calculate the values of Ni, NT and then substitute in
this equation to find DN.
• Use the same date to find Dv and compare both.
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4. • Assume all energy delivered to mass appears as heat.
• Calculate volume
• Calculate power load in hp
• Since 1hp = 2545 Btu/h
• Heat to be removed = calculated power*2545
• Specific heat of water is 1.0 Btu/lb-F
• Cooling water required will be = (amount of heat)/(Temp)*(specific
heat of water)
• Units will be lb/h, convert into gal/min
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6. • To use this formula, calculate Ʃxi for run 1 and run 2
• Calculate N, which is total number of samples
• Calculate 𝑥 using formula 𝑥 = 𝑥𝑖/𝑁
• Calculate
• Take average of two runs for the value of µ
• Find the value of s for run 1 and run 2
• Calculate
• Calculate time required using this formula,
• value of k = 0.5
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7. • A) Calculate Ip using the value of S in the given equation.
• Locate Ip on the graph to both curves clay and heavy clay.
• Calculate time from x axis.
• For the maximum value of Ip for both clays, find out the S using above
equation.
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9. Chapter 30
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10. • Cut points are 8 mesh and 14 mesh
• Let’s say
• Coarse material = A
• Intermediate = B
• Fines = C
• Take basis of 100 lb feed
• Let: Dc = lb coarse material produced
• Dm = lb intermediate material produced
• Hence, fines produced = 100 - Dc – Dm
• Calculate amount of A, B and C in feed from table
• Then apply component balance
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11. • For coarse product, Ac=0.88 Dc , Bc = 0.12 Dc and Cc = 0 from table
• Similarly apply balance for intermediate and fines.
• Apply A balance and then B balance.
• Solve the equations simultaneously to remove the same parameters.
• Find Dc, Dm and fines.
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12. Effectiveness
• Calculate the values of Ac, Bc, Am, Bm, Cm, Bf and Cf from the
previous values.
• First screen will be 8 mesh. For this oversize is all retained over 8
mesh and undersize will be all passed through 8 mesh.
• Calculate EA and EB for first screen and then overall.
• Second screen will be 14 mesh. Oversize is all retained over and
undersize will be all passed through 14 mesh screen.
• Calculate EA and EB for second screen and then overall effectiveness.
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13. • Take basis of 100 metric tons feed per hour
• Top scree is 8 mesh, opening of the screen will be 2.362 mm from
Appendix 20 (Tyles standard screen scale)
• Capacity = 4*screen opening
• Area required (m2) = feed / capacity
• Bottom screen is 14 mesh, its opening will be taken from appendix
• Capacity = 4*screen opening
• Total feed to bottom screen calculated in prob 30.1 = 75.1 ton/hr
• Area required (m2) = feed / capacity
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14. Course for Endterm Examination
• Power point slides: Lecture 1-Lecture 26
• Recorded Lectures: Lecture 3-Lecture 25
• Topics in detail as discussed in lectures:
(1)Characterization of the particles: (a) Shape factor and sphericity of particles (b) Mean diameters (c) Density of
mixture of solid particles
(2) Screening: (a) Types of screens (b) Factor affecting screening operations (c) Screen effectiveness (d) Cumulative
and differential analysis for particle size distribution (e) Size frequency curve and its importance (f) Specific number of
particles (g) Specific surface of a mixture of solid particles
(3) Storage and handling of solids: (a) Jansen Equation (b) Mohr’s Stress circle (c) Angles of repose, internal friction
and wall friction (d) Factors affecting the choice of storage vessel
(4) Mixing: (a) Types of mixers for continuous and discrete solids (b) Factors affecting mixing operations of solids (c)
Mixing index (d) Axial mixing and its importance (e) Rate of mixing
(5) Size reduction: (a) Basic modes of size reduction, size reduction laws (b) Size reduction machines (c) Angle of nip
for double roll crusher and jaw crusher (d) Critical speed of ball mill and various actions in the ball mill operation (e)
Selection criteria of size reduction machines
(6) Introduction to filtration: (a) Types of industrial filters (b) Pressure drop calculation in filter operation (c) Time
required for filtration
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