Types of Fine grinding mills: | 1 Roller mill: Crack-U-Lator, 1-300 mm
2 Hammer mill: Fitzmill comminutor,10-<10000 mm
3 Chaser mill
4 Centrifugal-impact mill and sieve: Quick sieve, Turbo sieve, CoMill
5 Cutter mill: 80to100 mesh (0.177-0.149 mm)
6 Attrition mill
7 Pebble or ball mill: Pot mill or Jar mill, 1-300 mm
8 Vibrating ball mill
9 Fluid-energy mill: jet mill, doughnut shaped mill, 1 to 20 mesh (25.4-0.841 mm)
10 Centrifugal-impact pulvurizer |
done through attrition action, for soft but not
abrasive substances, they do not cause
damage or removal of surface materials
Types of Fine grinding mill | Roller mill: Crack-U-Lator, 1-300 mm |
all drugs but not abrasive
drugs
Types of Fine grinding mill | Hammer mill: Fitzmill comminutor, 10 -
<10000 mm |
used too heavy granite stone
that are mounted vertically like wheels that
are made to revolve
Types of Fine grinding mill | Chaser mill |
combines
sieving and milling into a single operation
Types of Fine grinding mill | Centrifugal-impact mill and sieve: Quick
sieve, Turbo sieve, CoMill |
useful in reducing particle size of
fibrous materials and they act buy cutting
and sharing action; not for fiable materials
Types of Fine grinding mill | Cutter mill: 80 to 100 mesh (0.177-0.149
mm) |
uses two stones or steel
grinding plates or one or both of which
revolve to provide grinding; used for soft
fibrous materials but not abrasive
Types of Fine grinding mill | Attrition mill |
slow process in reducing particle
size; uses attrition and impact action
Types of Fine grinding mill | Pebble or ball mill: Pot mill or Jar mill, 1-
300 mm |
with ball inside
Types of Fine grinding mill | Vibrating ball mill |
solid materials are subjected to streams of
high velocity elastic fluid; for moderately hard
and friable material and not for soft and
sticky material
Types of Fine grinding mill | Fluid-energy mill: jet mill, doughnut
shaped mill, 1 to 20 mesh (25.4-0.841 mm) |
use for
heat sensitive material
Types of Fine grinding mill | Centrifugal-impact pulvurizer |
➢ A process of reducing the size of the
dispersed phase in dispersion
➢ Only use for dispersed system or two phased
system | HOMOGENIZATION |
Equipment for HOMOGENIZATION | 1 Colloid mill
2 Homogenizer |
involves the passage of mix phases of
dispersion between a stator and a high-speed rotor | Colloid mill |
– involve the passage of mix phases of
dispersion between a finely grounded valve and they
will sit under a high pressure | Homogenizer |
• Method of preparation HOMOGENIZATION | • Solutions:
- simple solution,
- solution by chemical reaction,
- solution by extraction
• Suspensions;
- dispersion or precipitation by double decomposition
- alteration of pH
• Emulsions:
- w/o. ingr are dissolved in the phase in which they are soluble then add internal phase to external phase,
- o/w, phase inversion technique, water phase is added to oil phase |