الفهرس 
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Abstract
This work concerned basically to investigate the peptization of high barite iron ore concentrate and Wadi Kareem iron ore concentrate. The results of this work can be summarizes in the following spots. 1- The pelletization of El-Gidida high barite iron ore concentrate fines, and the productivity of the green pellets were found to be very sensitive to any change in the operating parameters such as disc slope, residence time of material in the disc pelletizer and disc rotating speed ....etc. The results showed that the optimum conditions to obtain maximum productivity of-16 + 8 mm diameter green pellets with higher mechanical properties are:- a- Tilt angle of disc bottom 60°. b- Disc rotating speed 15 r.p.m. c- The time of ore charge in the disc pelletizer is 15 min. d- Feed size -200 mesh, e- Water added 10%. 2- The optimum conditions required for firing the concentrate of high barite are:- a- Firing temperature is 1300 °C. b- Firing time 25 min. 3- The fired pellets of high barite iron ore concentrate without any addition is not suitable for blast furnace, because the crushing strength is less than 200 kg/pellet. 4- The addition of starch or furan as a binder to high barite iron ore concentrate are not acceptable to produce pellets suitable for blast furnace. 5- The 12% water added is suitable for the pelletization with bentonite. 6- The compressive strength of fired high barite iron ore concentrate pellets are increased by increasing the percentage of bentonite. 7- The reducibility of the fired pellets decreased as the amount of bentonite increased 8- The controlling mechanism of reduction of pellets containing 1.5% bentonite are gaseous boundary layer diffusion for reduction extent 50% and gaseous diffusion through the porous of the pellets for reduction extent 50-80%. 9- Increasing lime addition up to 1% the crushing strength of fired pellets were increased, while when lime increased more than 1 % lime the crushing strength decreased. 10- The kinetic reduction of pellets contain 1% lime confirmed the gaseous boundary layer diffusion is controlling mechanism for reduction extent up to 50% while for reduction extent range from 50% the controlling mechanism is gaseous diffusion through the porous reaction product. 11 - The addition of 30% Wadi Kareem iron ore concentrate to the high barite iron ore concentrate with 1% lime is suitable to gave fired pellets have compressive strength more than 200 kg/pellet. 12- The activation energy of reduction pellets contains 30% Wadi Kareem are 32.8 and 41.8 kj/mole for the reduction extent 50% and 80% respectively. The controlling mechanism for 50% reduction for pellets contain 30% Wadi Kareem and 1% lime is combined mechanism while for 80% reduction the mechanism of reaction is chemical mechanism. key Words: Pelletization, Reduction, Reduction kinetic, Strength of pellets.