| Abstract: |
The River Nile has a dominating influence on the country’s economic, cultural, public health, economic social and political aspects. It constitutes over ninety percent of fresh water resources of Egypt. It is the main source of drinking water, beside its The Nile water are subjected to different sources of pollution, which affect its physical, chemical and biological characteristics, these sources including industrial, agricultural and municipal wastes. From year to year pollutants accumulate and there arTherefore, the first objective of this work is to study physical and chemical characteristic of Nile water. In this study water samples, were collected from ten locations during February (1999) to determine the quality of the Nile water. In addition waterThe results obtained from this study could be summarized in the following two main categories:I- Physico-chemical assessment of water quality of the River Nile, agricultural and industrial wastewater.1- pH values along the main River Nile ranged between 8.16 and 8.88 (slightly alkaline). From industrial outfalls ranged between 1.7 (highly acidic) at El Hawamdia chemicals and 9.5 (alkaline) at Coca cola, and for agricultural outfalls ranged between 6.32- Dissolved oxygen values along the main River Nile ranged between 7.4 mg/l at Kom ombo site and 9.3 mg/l at El Minya site. From industrial outfalls it ranged between 2.18 mg/l (Sohag oil) and 5.35 mg/l (Chema) and for agricultural outfalls it ranged bet3- Nitrate concentration in the main River Nile ranged between 1.2 mg/l at Benisuef site and 1.9 mg/l at Esna site. From industrial outfalls it ranged between 1 mg/l (Dishna sugar) and 2000 mg/l (Chema), and for agricultural outfalls it ranged between 1.44- BOD concentration in the main River Nile ranged between 0.9 mg/l at El Minya site and 4.5 mg/l at Assuit site. From industrial outfalls it ranged between 1.5 mg/l (Mankabad) and 445 mg/l (El Hawamdia chemicals), and from agricultural outfalls it ranged5- COD concentration in the main River Nile ranged between 2 mg/l at Naga-Hammadie site and 23 mg/l at El Minya site. From industrial outfalls it ranged between 12 mg/l (Edfu iron alloys) and 5600 mg/l (El Hawamdia chemicals), while for agricultural outfa6- The oil concentration in all sites along the main River Nile(0.29 mg/l ----1.5 mg/l) exceeded the permissible limits (0.1 mg/l).The oil concentration for industrial outfalls ranged between 0.345 mg/l (Edfu iron alloys) and 48.400 mg/l (El Hawamdia chemicals), while for agricultural outfalls it ranged between 0.172 mg/l (Ghamaza El Soghra) and 8.570 mg/l (El-Berba).7- Determination of heavy metals (Cr, Ba, Co, Ni, Pb, Cd, As, Zn) along the River Nile shows that:- The maximum concentration of Cr, Ba, Co, Ni, Pb, Cd, As, and Zn were 0.012, 0.065, <0.005, <0.005, 0.017, 0.001, <0.01 and 0.121 mg/l, respectively during Feb.1999, but during Feb. 2000 the maximum concentration were 0.016, 0.083, 0.005, 0.006, 0.024, 0- For industrial outfalls, the maximum concentration of Cr, Ba, Co, Ni, Pb, Cd, As, and Zn were 0.069, 0.222, 0.008, 0.102, 0.078, 0.015, 0.02 and 0.710 mg/l respectively, during Feb.1999, while for agricultural outfalls the maximum concentration were 0.08- The overall water quality status of the River Nile through calculation of average water quality index (AWQI) using seven important selected physico-chemical parameters indicated that about 40% of all sites along the River Nile suffering from pollution.II- Water with a high degree of purity is rarely obtainable from natural sources. A knowledge of the impurities which will probably be present and to remove it is, therefore, desirable.For this reason it is recommended to use membrane filtration system as a new technology for treatment of the drinking water.The application of membrane technology is expanding worldwide, and is receiving increased attention as one of the few technologies capable of reliably meeting increasingly stringent regulatory requirements for drinking water quality. This expansion is alsMembrane systems have been used for many years for desalination of sea water for provision of drinking water. In addition to reverse osmosis treatment facilities, nanofiltration and ultrafiltration membranes are increasingly being used for removing mineraMembrane filtration processes are all based upon pressure driven flow through a semi-permeable membrane. All of these techniques started to be used in Alexandria (Borg El Arab station).Nanofiltration (NF) separation incorporates a membrane with pore sizes and operating pressures between the ultrafiltration and reverse osmosis membranes. They are typically operated at pressures in the range of 70 to 200 psi. Nanofiltration membranes prevNF features has a low selectivity for monovalent cations salts and organic substances with MM less than 150 and a higher selectivity for di-and polyvalent cation salts and organic substances with MM greater than 300.In this study case advanced membrane systems has been used for drinking water treatment at El Giza site.The results of laboratory experiments on the feed and product water showed that :1- The overall removals of BOD at sites are varying from 72% to 89%.2- Removal of Ammonia (NH3 ) ranged from 66% to 100%.3-H2S removals ranged from 67% to 91%.4-Phosphate removal ranged from 22% to 68%.5-Removal of calcium hardness reached to 72%.6-The removal of iron, zinc, cadmium and manganese reach to 100% in all sites under study.7-The removal of COD reach to about 70%.8-The removal of TDS reach to about 19%.The data obtained from El Ameria water treatment plant showed that:The percentage of removal of Sodium ion varied from 94.7 to 95.8 while, for Calcium ion the percentage reach to 95.8%. Moreover, the percentage of anion(Cl-, HCO3-, SO4--) reached to 96.25, 89.8 and 96.3% respectively.Generally, the removal of TDS was reached to 95.8%.
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