الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Developed countries have recently found their environ mental protection efforts towards the control of hazardous waste. In Egypt, we don’t have any specific laws governing the control and disposal of hazardous wastes. The objective of this study is to segregate the most hazardous processing effluent fro~ selected industries namely (El-Nasr Tannery, AKFC, and Ismadye) and treat it separately to reduce the final pollution load and treatment cost. The programe included characterization of hazardous processing effluents, application of possible treatment to reduce or eliminate its toxicity, and selection of opti mum treatment conditions. The proposed treatment methods and their efficiencies were variable. Selection of appro priate treatment technology was based on three major para meters namely; economic, technical anq efficiency of pollu tants removal. The general characte~ization of the ~ested specific effleunts showed the following: 1. Ammonia is the main polluti~n constituents in the ammonia synthesis processing waste and cooling water at AKFC as shown in table (Ill). 2. Chrome tanning liquor waste generating at MIC is char a cterized by high concentration of chromium beside the other pollution constituents of organic and inorganic nature as indicated in table (V). 3. The organic dyes and heavy metals are the main pollutants in the selected dye processing effluents generating at Ismadye. The summarized treatment results are: 1. Air stripping achieved variable percent removals of ammonia with a maximum of 98 percent at an aeration time of six hours and at pH 11.5 as shown in figure (5). ~ 2. Chromium removals at 99.99 percent were achieved at high pH’s specially pH 9 - 9.5 by lime addition. Color due to chromous ions was consequently reduced. The formed chro mic hydroxide acted as an internal coagulant for the rest of the pollutants leading to their’moderate removals as shown in table (VI) appendix (Ill). Addition of active carbon adsorption at a dose of 750 mg/l in the previously pH adjusted effluents gave high effi ciencies of removals for heavy metals, dissolved organics as well as residual chromium. from the economic point of view, the use of high carbon dose is expensive, and its technique requires installation of complex equipment and high investments for construction and operation of the I , adsorption unite. 3. Ferric chloride was the most preferable coagulant to treat disperse blue dye waste as the required dose was the small est leading to saving in cost and reduction in sludge vol ume to be handled. 4. The application of AC adsorption to the raw acid green dye waste and to the raw basic blue dye waste achieved successful results. At carbon dose 300 mg/l, maximum per centage removals of the tested parameters were achieved for the acid green dye waste, while dose 400 mg/l achieved maximum percentages removals for the basic blue dye waste. The adsorption isotherms were deduced to supply the basic information necessary to design adsorption column. 5. Reactive violet dye waste was treated by oxidation using calcium hypochlorite as a source of chlorine to oxidize cyanide to cyanate. Chlorine dose (1600 mg/l) achieved maximum removals of color, copper, COD and V.S. Then the treated effluent was acidified using hydrochloric acid (1:1) to ensure complete oxidation of cyanate compound to carbon dioxide and ammonia. At pH 2, the maximum per cent age removals of color, COD and V.S. were achieved. Sand filtration followed by AC adsorption were used to improve the removal efficiency of the residual organic matter. The application of this scheme was expensive. Improved housekeeping, up-grading of production techno logy can achieve significant reduction in the pollutional load leading to appreciable saving in treatment costs.