الفهرس 
Dyeing as a New Environmental ChallengeOnly 14 pages are availabe for public view
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Abstract
In many countries the textile industry discharges its aqueous effluent to municipal treatment plants which are biological in nature and designed for the treatment of domestic rather than industrial effluents.Thus substances that are biodegradable or insoluble are removed non-biodergradable substances pass through uncharged and are discharged to the receiving river.A very simplified description of stw is:coarse screens-fine screens-primary settling-aerobic biological treatment-tertiary settling-discharge to river.After the tertiary settling a proportion of the sludge is recycled to maintain the biomass concentration while the excess goes either to anaerobic digestion or incineration.Of the various dyestuff types that enter an stw,those that are insoluble in water will be removed at the primary settling stage.Water soluble dyestuffs will pass to biological treatment.Dyestuff manufactures have expanded a great deal of research on the development of dyestuff that are as stable(fast)as possible,so it is not surprising that their aerobic biodegradability is low.Of the water soluble dyestuff classes basic and direct dyes are almost completely removed by bioelimination as are most(but not all)acid dyes.