الفهرس 
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Abstract
RAKTA pulp and paper company, reputable as the largest paper making. plant in the middle East, is considered as one of the major polluters in Alexandria Metropolitan area. It discharges a large volume (79,846m3 Id) of heavily polluted wastewater without any pretreatment into the Abu Kir Bay leading to a massive deterioration of its water quality, physically, chemically, and biologically. This study aimed at characterizing the major effluents discharged from the different processes at RAKTA pulp and paper. .milL with respect to quantities (material balance) and qualities (physico-chemical analysis), and to study the possible means of . lowering the pollution loads; particularly; with respect to the discharged black liquor which constitutes the major serious pollutant. The results indicated that: i. The straw washing section discharges 18948 m3 Id wastewater and this waste is characterized by a high suspended solids content (4g/l) which imparts opalescence appearance to the receiving stream. ii. The pulping section discharges 25793 m3 Id wastewater (BL) containing 1.1 soluble solids and corresponding to a daily discharge load of 242 ton of organic and 40.8 ton of sodium salts. The BL is characterized by high pH and high organic load of 3.95 g BOO jL and 12.033 g coojL. The high COD value with respect. to BOD indicates the presence of high fraction of nonbiodegradable organic matter (lignin) that causes a serious effect on the receiving stream. Hi. The bleaching section discharges 14681 m3 jd wastewater which contains 1.485 g coojl and 0.76 g BOojL . iv. The paper machine section discharges 20424 m3 jd wastewater (white water) which is loaded with high suspended solids (1.5 gll). This is due to the inefficient save all system. It is clear that the BL, which represents 33 of the final effluent, is considered the most serious pollutant of the RAKTA mill. Pollution abatement of the BL is usually carried out in chemical and heat recovery units. Such chemical recovery of the RAKTA BL is not technically or economically feasible due to the high silica content (10. with respect to BL total solids) of the black liquor and high dilution of the BL (1.1 ) that makes the heat recovery not economically feasible. Due to the difficulty of chemical recovery, the alternative integrated anaerobic- aerobic system (ANAMET) \,.as studied to reduce the organic load of the RAKTA BL. This ne\,. system has been applied successfully in two mill; SAICA mill in Spain and Hyite Brunks AB mill in Sweden. In the present thesis, the ANAMET system was applied for biodegradation of RAKTA BL using either conventional micro organisms (rumen microorganisms used for anaerobic bio degradation and domestic sewage microorganisms for aerobic biodegradation) or non-conventional microorganisms (marine bottom sediment microorganisms from Abu Kir Bay used for anaerobic biodegradation and aerobic marine microorganisms for aerobic biodegradation). The followipg items summarize the performance of ANAMET system used for biodegradation of BL using conventional microorganisms: The anaerobic acclimatization phase was accomplished over 16 weeks, where, the rumen microorganisms was acclimatized to COD load of the present RAKTA BL effluent (14.78 g/I). The reactor performance showed a gradual improvement of biomass formation and organic load reduction. The aerobic acclimatization phase (using domestic sewage microorganisms) was accomplished over 60 days, where MLVSS reached 1.5-2.0 g/I. The ANAMET system was evaluated for biodegradation of BL at variable loads; gradual increase of load, shock load, and uniform load. It achieved the following results: i. The feeding of the anaerobic reactor with gradual increase of organic load from 15.625 g COD/I to 45.2 g COD,’I at the optimum HRT of 7 days, with the aim to increase the concentration of RAKTA BL effluent discharge, indicated that the COD reduction ranged from 55 to 65 while the BOO reduction ranged from 78 to 85. The biogas production increased from 2.8 IIJiof\.lwasle-1 to 6.77 IIJiog.lwasle-1 with increasing of organic load.