
182 Advanced Process Control and Simulation for Chemical Engineers
The melamine aggregates were been saturated surface dry. Therefore, melamine
aggregates immerse in water at approximately 21
o
C for 24 hr and removing surface
moisture by warm air bopping.
FIGURE 2 The SEM photographs of materials: (a) melamine aggregates and (b) silica fume.
13.2.4 Aluminum Powder
Aluminum powder was selected as an agent to produce hydrogen gas (air entrainment)
in the cement. This type of lightweight concrete is then called aerated concrete. The
following are possible chemical reactions of aluminum with water:
2Al + 6H
2
O 2Al(OH)
3
+ 3H
2
(1)
2Al + 4H
2
O 2AlO(OH) ...