Characteristics Of Process Waste Water In The Textile Industry

What is process waste water?

The textile industry is a huge sector where a large number of waste streams or effluents are significantly produced. Basically, the effluent which is produced in different sectors of the textile industry is dangerous to the environment. Mainly effluent is produced from different sectors such as de-sizing, scouring, bleaching, mercerizing, dyeing, printing, finishing, washing, and others process. This type of wastewater contains harmful chemicals to the environment, and for this reason, it needs to purify before being discharged into the environment. Hence, an Effluent treatment plant is used for treating the effluent which is come from the textile or other chemical industry.

Characteristics of Process Waste Water in the Textile Industry

Now, I will show you the processing unit of the textile industry from where effluent is produced, possible pollutants contain in water as well as the nature of wastewater. Therefore, it must help us to get the general concept of the effluent of the textile industry and we can set up ETP for treating the effluent.

Desizing

We know that size materials are generally applied on the yarn surface in the weaving sector. However, the removal process of size materials from the fabric is called de-sizing and possible pollutant in water is Starch, Glucose, CMC, PVC, Resin, Fats, Oils, etc. The nature of the wastewater is also high BOD (35-50%) of the total.

Scouring

Scouring is the process by which impurities in textile materials are removed. Possible pollutants in water are NaOH, Na₂CO₃, Waxes, Grease, Fragments of cotton, etc. The nature of waste water is strongly alkaline, dark in color, and has a high BOD (30%) total.

Bleaching

The natural color of the textile materials is removed by the bleaching process. Possible pollutant in water is Na(0Ocl)Cl, NaOH, Cl2, H2O2, Na2O2, acids, etc. The nature of wastewater is alkaline, with BOD (5%) of the total.

Mercerizing

It is an additional process to improve the physical properties of the fiber. Possible pollutant in water is NaOH, H2SO4, Na2CO3, etc. The nature of waste water is strongly alkaline, BOD (less than 1%).

Dyeing

The dyeing unit is the main production house for wastewater. Waste water that is produced in yarn dyeing, woven dyeing, or knit dyeing units is highly polluted. Possible pollutants in water are various Dyes, Salts, Acids, Alkalis, soaps, detergents, etc. The nature of waste water is strongly colored, with a fair BOD (6%) of the total.

Printing

Various type of decorous design is formed by the printing process. Possible pollutant in water is Colors, Pigments, Gums, Oils, Acids, different salt, and other auxiliaries. The nature of wastewater is highly colored, oily appearance, with BOD (6 to 10%) of the total.

Finishing

Different types of finishing are applied in the finishing section. Possible pollutant in water is Traces of Starch, Resin, Softeners, Stiffeners, etc. The nature of wastewater is low BOD (2 to 4%) of the total.

In sum, to protect the environment from the harmful effects of the effluent of the textile industry, the owner of the industry should set up an Effluent Treatment Plant (ETP).