الفهرس 
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Abstract
The introduction discusses Source of CKD is a fine-grained hard material created from cement production and is considered as the main by-product from the cement making process. characteristically, cement is being created at high temperatures within a massive rotary kiln. It is where the finely powdered raw materials enter and transfer downward to the cold end of the kiln, whereas the fuels and combustion air are being presented and drawn upward from the hot end of the kiln.
CKD is a grey or white colour solid dusty material in room temperature. Its appearance is like to Portland cement. It is odourless and it may have a high average pH value which ranges from pH 12 to pH 13 when it is soluble in water. However, it is only slightly soluble in water with a solubility of 0.1% to 1%. Furthermore, CKD has a high boiling point which go above 1000℃ (>1832℉). Its relative density is nearly 2.3 to 3.15 g/cm3
Chemical Properties of CKD
Oxides Fresh CKD Calcined CKD
SiO2 11.47 14.96
Al2O3 1.95 3.18
Fe2O3 0.01 0.01
CaO 53.67 54.8
MgO 0.13 0.15
SO3 12.4 14.47
Cl 2.4 2.76
K2O 0.11 0.0
NaO2 0.35 0.28
LOI 29.7 3.7
Total 82.48 90.6
Hydration can be define as a sequence of chemical reactions occurs between a cementitious material and water to generate products called hydrates which donate a solid mass It is being deduced that the free-lime (CaOf ) content in CKD will enlarge the ambient temperature because alteration of CaOf to Ca(OH)2 is considered as an exothermic chemical reaction
Chapter (2)
Preparation of Starting Materials:
Grog:-
The fired clay bricks(/Grog) were crushed by Jaw crusher and finely ground by using a laboratory small steel ball mill having a capacity of one kilograms. The ground aluminosilicate fired clay bricks passed through 90 micron B.S. Sieve and residue on sieve was 1.5 % then sieved through 45 micron retaining residue of 13.6 % on sieve.
Metakaolin:-
Kaolin was burnt in muffle furnace from room temperature up to 800°C then left at 800°C for two hours with 6oC/min. The MK was crushed by Jaw crusher and finely ground using a laboratory small steel ball mill having a capacity of one kilograms. The ground MK passed through 90 micron B.S. sieve and residue was 1.0 % then sieved through 45 micron and the residue was 12.8 %.
Silica fume:-
Silica fume, also known as microsilica, is an amorphous (non-crystalline)polymorph of silicon dioxide, silica. It is an ultrafine powder collected as a by-product obtained from the reduction of high – purity quartz with coal or coke and wood chips in an electric arc furnace during the production of silicon metal or silicon alloys of the silicon and ferrosilicon alloy production industry and consists of spherical particles with an average particle diameter of 150 nm.
Fresh cement kiln dust (CKD):-
Fresh Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. It is created in the kiln during the production of cement clinker. The dust is a particulate mixture of partially calcined and unreacted raw feed.
Calcined cement kiln dust(CKD):-
Calcined Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. It is created in the kiln during the production of cement clinker. The dust is a particulate mixture of calcined at 1000 °C and was burnt in muffle furnace from room temperature up to 1000°C then left for two hours with 6 °C.
Methods of Investigation:
Water of Consistency and Setting Time:
Determination the water of standard consistency:
The introduction discusses Source of CKD is a fine-grained hard material created from cement production and is considered as the main by-product from the cement making process. characteristically, cement is being created at high temperatures within a massive rotary kiln. It is where the finely powdered raw materials enter and transfer downward to the cold end of the kiln, whereas the fuels and combustion air are being presented and drawn upward from the hot end of the kiln.
CKD is a grey or white colour solid dusty material in room temperature. Its appearance is like to Portland cement. It is odourless and it may have a high average pH value which ranges from pH 12 to pH 13 when it is soluble in water. However, it is only slightly soluble in water with a solubility of 0.1% to 1%. Furthermore, CKD has a high boiling point which go above 1000℃ (>1832℉). Its relative density is nearly 2.3 to 3.15 g/cm3
Chemical Properties of CKD
Oxides Fresh CKD Calcined CKD
SiO2 11.47 14.96
Al2O3 1.95 3.18
Fe2O3 0.01 0.01
CaO 53.67 54.8
MgO 0.13 0.15
SO3 12.4 14.47
Cl 2.4 2.76
K2O 0.11 0.0
NaO2 0.35 0.28
LOI 29.7 3.7
Total 82.48 90.6
Hydration can be define as a sequence of chemical reactions occurs between a cementitious material and water to generate products called hydrates which donate a solid mass It is being deduced that the free-lime (CaOf ) content in CKD will enlarge the ambient temperature because alteration of CaOf to Ca(OH)2 is considered as an exothermic chemical reaction
Chapter (2)
Preparation of Starting Materials:
Grog:-
The fired clay bricks(/Grog) were crushed by Jaw crusher and finely ground by using a laboratory small steel ball mill having a capacity of one kilograms. The ground aluminosilicate fired clay bricks passed through 90 micron B.S. Sieve and residue on sieve was 1.5 % then sieved through 45 micron retaining residue of 13.6 % on sieve.
Metakaolin:-
Kaolin was burnt in muffle furnace from room temperature up to 800°C then left at 800°C for two hours with 6oC/min. The MK was crushed by Jaw crusher and finely ground using a laboratory small steel ball mill having a capacity of one kilograms. The ground MK passed through 90 micron B.S. sieve and residue was 1.0 % then sieved through 45 micron and the residue was 12.8 %.
Silica fume:-
Silica fume, also known as microsilica, is an amorphous (non-crystalline)polymorph of silicon dioxide, silica. It is an ultrafine powder collected as a by-product obtained from the reduction of high – purity quartz with coal or coke and wood chips in an electric arc furnace during the production of silicon metal or silicon alloys of the silicon and ferrosilicon alloy production industry and consists of spherical particles with an average particle diameter of 150 nm.
Fresh cement kiln dust (CKD):-
Fresh Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. It is created in the kiln during the production of cement clinker. The dust is a particulate mixture of partially calcined and unreacted raw feed.
Calcined cement kiln dust(CKD):-
Calcined Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. It is created in the kiln during the production of cement clinker. The dust is a particulate mixture of calcined at 1000 °C and was burnt in muffle furnace from room temperature up to 1000°C then left for two hours with 6 °C.
Methods of Investigation:
Water of Consistency and Setting Time:
Determination the water of standard consistency:
The water of standard consistency, initial and final setting times of the prepared pastes were carried out according to (BS EN 196-3: 1994) using Vicat apparatus. A certain weight (500 g) of CKD sample and a quantity of water (ex. 125 g) were put in the mixer bowl (HOBART, model N 50, Canada). The mixer was run at a low speed of 140±5 rpm for 90 seconds then stopped for 15 seconds during which remove by means of suitable plastics scraper all the paste adhering to the wall of the bowl in the middle of the bowl.
Density (dp) was carried out before the specimens subjected to the compressive strength determination. Samples were weighed suspended in water and in air (saturated surface dry). Each measurement was conducted on at least three similar cubes of the same mix composition and age. The density was calculated using the following formulas:
Saturated weight
Bulk density = ( g/cm³ )
Volume of sample
Saturated weight-suspended weight
Volume Sample = (cm³)
Density of water
Saturated weight
Bulk density = (g/cm³)
Saturated weight-suspended weight
Compressive Strength Determination:
Compressive strength is defined as the maximum compressive stress withstand without failure. When the limit of compressive strength is reached, materials are crushed. In each case this test was carried out on three one inch cubes following the procedure described by (ASTM C150-07, 2007). Three cubes of the hardened paste representing the same paste blend at each curing time were used for the determination of compressive strength of the hardened paste and the average was considered. Great care was taken to keep the specimens in saturated condition to avoid loss of water filling the pores of the
Total Porosity:
After the determination of bulk density and water content of specimens, the total porosity of the hardened cement pastes
1 + Wt
Total porosity ( Ɛ ) = ______________ x 100
0.99 We × dp
Chapter (3)
Chapter three illustrates technical results of Mechanical properties of prepared alkali activated products the presence of higher amount of reactive silica and alumina from grog with calcium and silica from calcined WCKD tends to formation of higher amount of geopolymer, CSH and CASH gels which increase the strength of that sample as compared to the other specimens. The dissolution of calcium ion to form CSH is increased with increasing the acidity (silica). Also, the calcination of WCKD has positive effect on improving the strength since some reactive oxides are formed after calcination
that the apparent porosity decreases with increasing the amounts of added silica fume or metakaolin or grog. This is due to the formation of sodium aluminum silicate hydrate geopolymer gel and/ or CSH hydrate gel which close the pores and consequently decrease the porosity. It is also indicated that the trend of bulk density is opposite to the trend of apparent porosity.
The phase composition of some selected alkali activated products prepared from WCKD/silica fume, WCKD/metakaolin and WCKD/Grog is
consist mainly of calcite, quartz and calcium silicate hydrate (CSH). The calcite and quartz are unreacted phases
After autoclaving, many phases are appeared in the pattern. These phases are calcite, lime, portlandite, quartz, CSH, C2S, C3S, CaSO4.2H2O, and CaSO4. Some of them are major phases and others are minor.
Chapter (4)
According to achieved results . The followings are the concluded remarks: White-cement kiln dust was successfully used in production of some alkali activated products in presence of silica fume or metakaolin or grog with alkali activator using direct reaction of starting materials or by hydrothermally treatment of casted raw materials. The reactivity of partner materials (silica fume, metakaolin and grog) is the key point for production of alkali activated products with improved properties.