الفهرس 
Chapter IOnly 14 pages are availabe for public view
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Abstract
The present study was mainly directed to possibility of utilization of cement kiln dust and granulated slag in the production of building materials. Cement kiln dust (CKD) is accumulated in relatively large amounts during the manufacture of portland cement clinker by the dry-process in Egypt. The accumulation of cement kiln dust within the area of cement industries and its spreading in the surrounding atmosphere represent a big environmental problem of pollution. Also, granulated blast-furnace slag and condensed silica fume, as representing the solid by-products of big iron industry and ferro-silicon alloys, respectively, were also used as starting materials.
Two hydration reaction were studied these are: (i) raw cement kiln dust-slag-silica fume hydration reaction and (ii) washed cement kiln dust-slag-silica fume hydration reaction. Five cement kiln dust-slag-silica fume Mixes were prepared in the weight ratios 20: 80: 0, 20: 78: 2, 20: 75: 5, 20: 70: 10 and
20: 60: 20. The pastes were made using three water/solid ratios
of 0.30, 0.40 and 0.50. The hydrated specimens of each Mix were cured for 0.021, 0.083, 0.25, 1, 3, 7, 28, 90 and 180 days. For each specimen the chemically-combined water and free lime contents were determined at various ages of hydration. The electrical conductivity measurements were carried out for each Mix using water/solid ratios of 0.30, 0.40 and 0.50 at two different hydration temperatures of 30 and 50°C.