Dyeing, textile processing wastes

In 1980, approximately 111,000 t of synthetic organic dyestuffs were produced in the United States alone. In addition, another 13,000 t were imported. The largest consumer of these dyes is the textile industry accounting for two-thirds of the market (246). Recent estimates indicate 12% of the synthetic textile dyes used yearly are lost to waste streams during dyestuff manufacturing and textile processing operations. Approximately 20% of these losses enter the environment through effluents from wastewater treatment plants (3). 

Recent estimates indicate 29t of the synthetic textile dyes used yearly are lost to waste streams during dyestuff manufacturing and textile processing operations. Approximately 20% of these losses enter the environment through effluents from wastewater treatment plants. 

Sulfonated azo dyes (reactive dyes) are widely used in the textile industry. Due to the simultaneous hydrolysis in the dyeing process, 15-60 % of the reactive dyes reach the waste water system. In addition, their use strongly increases with the colouring of natural fibres, and so a total of 60 % of all dyes emitted to the waste water are reactive materials. 

In addition to the dyebath, several auxiliary baths are used in batch textile processing to clean dyed goods and/or to fix the dye to the fiber. Considerable energy, water and chemicals are also wasted when these auxiliary baths are drained to the sewer. Plant pollution problems are also worsened by the additional effluent. Virtually all of the chemicals used in the auxiliary baths (sodium hydrosulfite and hydroxide, surfactants, etc.) are colorless, and thus do not lend themselves to simple... 

Large amounts of nitrosamines leak into the environment from the pharmaceutical and food industries, plastics industry, textile industry, waste transport (motor vehicles), industrial effluents (dyes, lubricants, mbber), and the production of solvents. Fuel manufacturing plants and oil refineries are also important emitters of nitrosamines, as well as landfills and fossil fuel combustion processes (to produce heat and power). These compounds naturally penetrate the environment through animal droppings. 

Flotaiion is a powerful mineral beneficialion tool that has wide potential in effluent treatments in tbe following industries 32 oil industry, engineering industry wastes, dairy wastes, food industry, textile fiber wastes, cellulose fibers, rubber wastes, asbestos wastes, polymeric wastes, paper industry wastes, dyes, electroplating industry, vegetable wastes, poultry processing wastes... 

Foamgard. [Rhone-Poulenc/Textile Rubber] Nonsilicone defoamer for carpet dyeing, dye baths, paper and pulp processing, waste treatment, print pastes. 

WASTES FROM TEXTILE PROCESSING Table 7.27 Dye Classes and Fibers... 

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