الفهرس 
INTRODUCTION AND OBJECTIVESOnly 14 pages are availabe for public view
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Abstract
This study was subdivided into two main parts. The first part discusses the effects of cadmium and zinc shock loads on both activated sludge and sequencing batch reactor systems. The second part aims to adopt a dynamic mathematical model to simulate SBR system. The proposed model was calibrated and verified according to experimental results.
In the first part, the performance and treatment capability of sequencing batch reactor and activated sludge systems under cadmium and zinc shock loads were investigated. Two pilot plant units, one for each system was used to study the effects of gradual increase of both cadmium and zinc on the treatment process. Batch tests were also performed to study the effects of both cadmium and zinc shock loads on the acclimated sludge collected from each pilot plants. The results of the pilot plant units showed that, the efficiency of COD removal decreased under the gradual increase of heavy metals. Whereas, the efliciency of COD removal was higher in the sequencing batch reactor pilot plant than the activated sludge pilot plant. Results of batch tests showed that, the efficiency of COD removal of the acclimated sludge collected from each pilot plant was higher than that the sludge collected from both systems before adding metals. Similarly this efficiency was higher in the sequencing batch reactor pilot plant than the activated sludge pilot plant operated under the same conditions. In the second part, the IAWQ Model No. 1(1987) was adopted to predict the biological reactions in the SI3R system. The proposed model was a reduced version of the IAWQ Model No. 1. The reduced version incorporates only these features which related to the utilization of carbonaceous material and nitrification in an aerobic SBR system with dump fill. The SBR proposed model was implemented on interactive simulation software (ISIM’ program). Comparisons were made between simulation results and data of laboratory experiments to indicate the validity of the model. The experimental work of this part was conducted in three cases of operations. The first case (control case) was used to calibrate the proposed model. Whereas, second and third cases (case I and case II) were used to verify the proposed model.
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