الفهرس 
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Abstract
In this study, dewatering of alum sludge using different processes was investigated. Chimney solar still was utilized to enhance drying rate. Chimney solar still gives better results than the basin type. Sludge SRF and moisture content are reduced by 93% and 83%, respectively. AOP (Fenton) reduce sludge SRF and moisture content by 73% and 65% in one minute, while Photo-Fenton reaction reduce sludge SRF and moisture content by 93% and 85%, respectively. UV radiation alone reduces the sludge dewaterability by 80%, 60%, after 10 minutes of reaction.
Eight models have been applied to describe the drying behavior of sludge cake at different computational techniques. It has been found that Excel spread sheet (x2= 3.7*10-3, R2= 0.95) was better than MATLAB (x2= 5*10-3, R2= 0.87). All the applied eight models in sludge drying gave good results except modified Page model. The best model which gave the highest results was two-term model (X2= 3.7*10-3 , R2= 0.96).
Mathematical modeling of air flow inside chimney was also investigated; chimney draft effect appeared in density and temperature plot inside solar chimney. CDF techniques are utilized to validate modeling of air flow inside solar chimney. Model is verified with error values of 10-4.
Treating alum sludge by Fenton processes is also modeled. Kinetic constants are obtained by linear regression analysis. Reaction between Fenton reagent and supernatant layer of alum sludge is second order (R2 = 0.70) in the first stage of reaction while zero order (R2 = 99) in the second stage of reaction.