ALTERNATIVE RAW MATERIAL SOURCES FOR CEMENT PRODUCTION
It is generally known that cement id produced from limestone, mar/clay and gypsum by the following three basic process- wet semi- wet aid dry process.
The cost of exploiting the limestone: the major raw material constitute about 50% of the production cost which results in the high cost of cement. It therefore becomes imperative to bring down the cost of cement by investigating into alternative source of raw material for cement production and hence this project.
From literature, rice husk ash, Ukpo day,& Nsu day contain the basic mineral constituents which limestone has. Rice husk was burnt temperatures of 5000c, 6000c, 7000c, and 8000c. The best ash was obtained at a temperature of 7000c,. the above material were also analyzed to determine their mineral constituents. The result shown that rice husk contains little aluminum (Al203) and no lime (Ca0). To make up for these mineral constituents, Upo day which is rich in aluming was blended with lime(Ca0)-a bye product from gas plant and the three minerals were blended using the method of lime saturation factor. A blending ratio of 70% lime 20% PHA and 10% Alumina mixture (Ukpo day) was used. The mixture was mixed dry by dry process and burnt in a furnace at a temperature of 12000c. the resulting mass known as dinker was ground with 5% gypsum. The cement obtained gave a comprehensive strength of 2N/mr2.
DEFINITION OF TERMS
OPC – Ordinary Portland cement
LSF – Lime saturation factor
Quicklime – Calcium oxide Ca0
Raw meal – Secondary raw material that is fed into the kiln for burning
Raw mill – A tube like machinery where the grinding of raw material
ASTM – American society for testing materials.
Hydraulic modulus – The ration of lime (Ca0) to silica, Alumina and ferric
Clinker – Intermediate raw material and the product from the kiln.
C3S – Tricalcimn silicate
C2S – Dicalcium silicate
C3A – Tricalcium Aluminate
C4AF – Tetra calcium Alumiroferite