الفهرس 
Chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
Conditioning treatment is performed on alum sludge for the object of enhancing its filterability, thus enhancing water removal from sludge. The sludge used in the experiments is obtained from Kedwan plant, Minia City, Egypt. Conditioners of different types are used, e.g., ferric chloride and lime (as an example of inorganic chemicals, Fenton reagent (adopted as one of the advanced oxidation processes) and Chitosan (adopted as a type of bio-polymers). The parameters studied are: effect of conditioner dose, effect of rate of mixing, effect of time of reaction and effect of pH value. The results of experiments showed that the minimum values for SRF (target of experiment) are 4.3*1012, 1.5*1012, 1.1*1012, 1.9*1011 and 3.2*1011 m/kg for conditioning with lime, FeCl3, Lime+FeCl3, Fenton reagent and Chitosan, respectively. These values represent a percentage reduction in SRF, compared to that of raw sludge, of 79.81, 92.96, 94.83, 99.11 and 98.49% for conditioning with lime, FeCl3, lime+FeCl3, Fenton reagent and Chitosan, respectively. Thus, Fenton reagent proved to be the best conditioner, among the conditioners examined, for conditioning alum sludge, followed by Chitosan.
In the second part of the study, the Response Surface Methodology (RSM) is chosen from the Design Expert program (version 12) and the Box-Behnken Design was employed to find factor settings that optimize the output response, i.e, percentage reduction in SRF (Red., %). The model obtained proved to be significant enough but with varying degrees. Fenton reagent showed to be the most favorable conditioner with a maximum percentage reduction in SRF of 99.57%. This is followed by Chitosan, lime+ ferric, ferric and lime which gave a value of 98.57, 96.2, 89.2 and 79.81, respectively for percentage reduction of SRF. Besides, lower concentration of the conditioner and lower speed of rotation are required when using Chitosan as a condition