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 of 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.
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 is the process by which impurities of the textile materials are removed. Possible pollutant in water is NaOH, Na2CO3, Waxes, Grease, Fragments of cotton, etc. The nature of waste water is strongly alkaline, dark color, high BOD (30%) total.
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.
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%).
The dyeing unit is the main production house of wastewater. Waste water which is produced in yarn dyeing, woven dyeing, or knits dyeing units is highly polluted. Possible pollutant in water is various Dyes, Salts, Acids, Alkalis, Soap, Detergent, etc. The nature of waste water is strongly colored, with fair BOD (6%) of the total.
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.
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 effect of the effluent of the textile industry, the owner of the industry should set up an Effluent Treatment Plant (ETP).