الفهرس 
Membrane technologiesOnly 14 pages are availabe for public view
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Abstract
This dissertation is mainly focuses on the treatment of industrial wastewater that is produced from recycled paper industry. The proposed treatment method is a combination of dark (DF) and photo fermentation (PF) process and the main concern is related to optimizing the operation condition without utilizing any external chemicals. Therefore, paperboard mill wastewater (PMWW) was used as the main carbon source without any pH control, since PMWW has initial pH and alkalinity of 7.39 ± 0.09 and 1005.6 ± 113.9 mgCaCO3/L, respectively. The experimental setup was carried out with up-flow intermitted stirring tank reactor (UISTR) which was evaluated under three different hydraulic retention time (HRT) of 48 h, 36 h and 24 h. This was corresponded to organic loading rate (OLR) of 2.19 ± 0.8 gCOD/L/day, 2.89 ± 0.07 gCOD/L/day and 4.42 ± 0.10 gCOD/L/day for DF process followed by 0.99 ± 0.09 gCOD/L/day, 1.55 ± 0.19 gCOD/L/day and 3.18 ± 0.20 gCOD/L/day, respectively for PF process. DF witnessed progressive H2 productivity (HP) increase from 0.17 ± 0.03 L H2/L/day to 0.72 ± 0.13 L H2/L/day with HRT reduction from 48 h to 24 h. This was in accordance with COD R% decline from 53.9 ± 5.3 % to 28.3 ± 3.8%. The reason for high COD R% with low HP at HRT of 48 h owing to the high produced amount of CO2 which contributed with 45.7% of COD R% while H2 donated only 5.7% of the removal efficiency. On the other hand, the DF effluent had ammonia concentration of 99.2 ± 18.4 mg/L when HRT was 48 h; this value was decreased to 64.4 ± 7.0 mg/L with shortening HRT to 24 h. Moreover, Ethanol dominated the soluble metabolites by-products (SMPs) with concentration of 266.0 ± 13.5 mg/L at HRT of 48 h, however, HRT of 24 shifted the degradation route to acetate dominance (411.4 ± 23.8 mg/L). Subsequent PF process was dependent mainly on the characteristics of the effluent of DF process. Low HP of 0.04 ± 0.01 L H2/L/day and 0.10 ± 0.02 L H2/L/day were registered at HRT of 48 h and 36 h. This is because the existence of ammonia in an inhibitory level. This was not the case for HRT of 24 h, in which, HP was significantly augmented up to 0.35 ± 0.15 L H2/L/day. The overall performance of the proposed configuration achieved maximum COD (R%) of 78.5 ± 4.6% coupled with HP of 0.21 ± 0.03 L H2/L/day at HRT of 48 h. In contrast, HRT of 24 h exhibited lower COD R% of 69.3% versus HP increase 5-folds higher than long HRT of 48 h. Therefore, the energy merit of HRT of 24 h supports its application with another subsequent reactor such as methane producing reactor for efficient disposal of the remaining organics.