Wastewater treatment textile dyeing plant

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. 

The elimination in wastewater treatment plants can be characterized by the range of P values as given in 22.2.1.2 (textile dyes), although paper dyes should be placed on the upper end of the range due to the larger molecular sizes. 

In the field of environmental applications, several new techniques are being introduced for the treatment of the different types of effluent generated by industrial plants. One of the most stringent environmental regulations is that governing the treatment and release of dye wastewater. It is estimated that about 700,000 tonnes of dye wastewater is produced annually [123,124], the majority of which comes from the textile, tannery, and pulp and paper industries [125]. Typical wastewater is fairly diluted and produced in large quantities, but even at very low concentrations, dye... 

Textile wastewaters can vary from slightly acid to highly alkaline depending on the individual processes carried out within the plant. They generally are alkaline when caustic scouring or mercerizing is involved. Heavy metals such as copper, chromium and zinc result from the use of certain dye carriers in the dyeing operation of synthetic fabrics and of blended fabrics, e.g., cotton and rayon. The pretreatment unit operations which may be necessary for various types of joint treatment facilities are listed in Table 6. 

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