الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Industrial development has been given a high priority in most developing nations because such development permits emp¬ loyment and generates revenue that enh~nce economic growth. Experimental studies were performed from October 1982 to January 1984, to assess the various waste treatment alternatives applicable to final effluents of major industries in Alexandria. Untreated wastes from selected industries are being discharged into the sea, drains, and I or sewers df Alexandria City, caus¬ ing remarkable pollution which lead to fish mortality. Edfina canningjKafr El-Dawar spinning and wea~ing, Varta Paper, Refractories, Copper Works, Misr Chemicals, Misr Rayon and Misr Dairy industries were chosen ~or the assessment of environmental impacts of the untreated and treated effluents using fish bioassays as a tool. The treatment alternatives investigated were: 1) Chemical addition with sedimentation. 2) Activated sludge process. . 3) Biofiltration system using sand filter. 4) Biocoagulation system. Results of the diffeient effluents analysed were: 1) Edfina wastes were characterized by having wide fluctuations contributed by putrifiable organic matter.as measured by COD, V.Rt. S.R. and high concentrationrof trace metals (Cu.,Fe., Mn.,Zn.,and ~ Pb) as shown in table (I). As shown in table (I) and figure (13) FeCl3 was the best coa¬ , gulant for the treatment of Edfina effluent reducing the mortality percent from 55 to about 4 rI) Kafr El-DawarSpinning and Weaving wastes were slightly alk¬ aline and having relatively high COD,S.R. and havirtg significant concentrations of trace metals (Cu.,Fe.,Zn.,Mn. and Pb) which lead to fish mortality. As shown in table (II),lime was the best coagulant for the treatment of Kafr El-Dawar spinning and weaving effluents, redu¬ cing the mortality percent from 40 to about 5 as shown in figure (16). Ill) The main pollution constituents in Varta Paper Processing wastes were high S~R., D.R. as well as high ~oncentrations of (Cu.,Fe.,Zn.,Mn.,and Pb.) as s~own in table (Ill). FeC13 at dose of (20-40) mg/l. was found to be the best coagulant which reduced the moratlity percent from 60 to about 5as shown in figure (19). Treatment of the. Varta raw wastes by activated sludge procedure followed by sand filtration reduced the mortality . rate to a maximum of 5 starting from 100 mortality. IV) Refractories effluents were characterized by high concent~rations of S.R,T.R and V.R as well as relatively high concentrations .L of (Cuo,Feo,Zn.,Mn.,and Pb~) as shown in table (IV). Biological and chemical treatment of Refractories wastes ~educed the mortality percent from 100 to about 17 and from 75 to about 20 respectively a shown in figures (21)and D2). v ) Copper Works effluents were characterized by having high solid contents, relatively high level of color, and significant concentrations of trace metals (Cu.,Fe.,Zn.,Mn., and Pb.). As shown infigures (24) arid (25)’, the raw wastes have low toxic effects on the tested f1sb, and biofiltration procedure reduced the mortality percent from ’50to zero. V 1) Misr Chemic’al wastewaters were charac~Tized by extremely high concentrations of,inorganic chemicals ~s measured by COD, ~R, ~R and T~ and high concentrations of trace metals (Cu.,Fe., Zno,Mn., Pb., and Hg.)” as well as high amounts of residual chlorine which lead to acute fish mortality even after chemical treatment as shown in figure (27). VII) Misr Rayon effluents were characterized ~y slightly alk¬ aline ang having high c~ncentration of organic matters as mess¬ ured by COD, and ~R induced by fibers, dyes and NaOH used in processing. The efflu~nts contain high ’level of ~R( 3433 mg/l) with the majority being organic., Lime was found to be the best coagulant for treatment which reduce the mortality percent from 100 ”to 5 as shown in figure (29). VIII) The main pollutant constituents in Da~ry wastes were high concentrations of putrefiable organic matter as measured by COD, Y.R and ~,releatively high level of color, and high concentration~ of(Fe.,Zn.,and Pb)as shown in table (VIII). The wastes were rap¬ idly putdfied thus decreasing the pH and reducing the efficiency removal by different treatment. Sand filtration Table{VIII) achieved the highest removal efficiency and reduced the fish mortality from 100 to about 40as shown in figure (32). Selection of appropriate treatment” technology was based on three major parameters namely, economic, technical and efficie¬ ncy of pollutants removal. Biocoagulation treatment was exclu¬ ded due to sophisticated control and. clo~e supervision required by the system, and its comparatively lower recovery performance. . Both chemical coagulation and biofiltration’systems can be used .for efficient treatment of most selected ~ndustry wastes. It is believed that the treatment costs are affordable and efficient operation and maintenance can be achieved.