Wastewater from textile plants is as diverse as the processes used in the industry. Still, one can make some general statements about the wastewater:
- it contains few bacteria
- the proportion of organic nitrogen is small
- heavy metals occur only when the use of metallic dyes
- temperatures are high, raw water being between 20°C and 30°C, sometimes even higher
- wastewater is generally alkaline
- the proportion of phosphates depends on the process used
An important criterion for estimating the afflux of wastewater is the extent to which dyes are diluted. The greater dilution, the more material will enter the wastewater.
In wet processing textiles there are four basic operations with their typical chemicals. The following table summarize these. |