INGENIEUR
Fly Ash from Coal
Power Plant
Raw
materials:
Limestone,
clay, etc.
Crushing & Grinding
Mixing
Pyro Processing
Cement
Clinker Grinding
Clinker Cooling
Figure 9: Block Diagram for Cement Production Process
Class Description Chemical requirements
F
C
Table 5: ASTM C618 Specification for Fly Ash
● Produced from burning anthracite or
bituminous coal
● Has pozzolanic properties but requires
● cementing agent
● Produced from lignite or sub-bituminous coal
● Has pozzolanic and some cementitious
properties
SiO 2
+ Al 2
O 3
+ Fe 2
O 3
≥ 70%
SiO 2
+ Al 2
O 3
+ Fe 2
O 3
≥ 50%
Table 6: CSA Specification for Fly Ash
Type
Chemical requirements
F < 8% CaO
Cl 8 - 20% CaO
CH > 20% CaO
Table 7: Examples of Raw Materials for Portland Cement Manufacture
Calcium Silicon Aluminum Iron
Limestone Clay Clay Clay
Marl Marl Shale Iron ore
Calcite Sand Fly ash Mill scale
Aragonite Shale Aluminum ore refuse Shale
Shale Fly ash Blast furnace dust
Sea shells
Rice hull ash
Cement kiln dust Slag
34 VOL 82 APRIL-JUNE 2020