Description
The chart “Manufacture of Cement & Quick Lime” (55×90 cm) provides a visual overview of the industrial processes for making cement and quick lime from limestone, making it ideal for classrooms or technical demonstrations.
Chart Features and Content
Size and Material: 55×90 cm, typically multicolor and laminated for long-lasting classroom display.
Cement Manufacture:
Raw Materials: Limestone (CaCO₃), clay/shale, and small amounts of iron oxide and gypsum.
Process Steps (Wet or Dry):
Crushing and mixing raw materials, then forming a slurry (wet) or powder (dry).
Heating in a rotary kiln (up to ~1500°C) where major reactions include:
CaCO
3
→
CaO
+
CO
2
CaCO
3
→CaO+CO
2
(limestone decomposition)
Formation of clinker materials:
2
CaO
+
SiO
2
→
2
CaO
⋅
SiO
2
2CaO+SiO
2
→2CaO⋅SiO
2
;
3
CaO
+
Al
2
O
3
→
3
CaO
⋅
Al
2
O
3
3CaO+Al
2
O
3
→3CaO⋅Al
2
O
3
.
Clinker is cooled, mixed with 2–3% gypsum, and ground into fine cement powder.
Quick Lime Manufacture:
Raw Material: Pure limestone (CaCO₃).
Process Steps:
Heating limestone in a lime kiln at 900–1000°C to decompose into quick lime (CaO) and CO₂:
CaCO
3
→
CaO
+
CO
2
CaCO
3
→CaO+CO
2
.
Cooling, handling, and (sometimes) further processing into slaked lime (Ca(OH)₂) by hydration.
Process Flow Diagrams: The chart usually depicts cross-sections or flowcharts of rotary cement kilns and lime kilns, with labeled zones for drying, calcination, clinkering, and cooling.
Product Uses: Key uses illustrated (construction, mortar, plaster, etc.).
Educational Value
Demonstrates similarities and differences in manufacturing two important construction materials, highlighting critical chemical changes and engineering steps.
Simplifies complex industrial processes with diagrams, arrows, and color coding for effective classroom explanation.
This chart is a comprehensive teaching resource for the manufacture and industrial relevance of cement and quick lime.