Öner E.

1st International Industrial Water Technologies Symposium and Fair, Bursa, Turkey, 6 - 09 December 2012, pp.1-7

  • Publication Type: Conference Paper / Full Text
  • City: Bursa
  • Country: Turkey
  • Page Numbers: pp.1-7


The pre-treatment, dyeing, finishing and printing processes in the textile industry use large amount of water and

the process effluents are characterized by high chemical oxygen demand (COD), dissolved solids, large amount

of organic chemicals, low biodegradability, strong colour and salinity. The wastewater treatment required to

minimize the adverse effect of the effluents to the environment is expensive and very difficult task. Therefore, the

minimization of water in the processes and the reuse of treated process wastewater are becoming more attractive

as the costs of chemicals, energy and wastewater treatment continue to rise. The minimization of process water

can be achieved either by the specially designed combined single-bath processes or by the modification of the

process equipment; and the reuse of the dyeing effluent is possible either by the direct dyebath reuse technology

or by the advanced treatment processes. In the single-bath processes, the scouring and bleaching, and even

dyeing processes can be combined to save water, energy and process time. The minimization of water is also

possible by the use of fully controlled equipment with low liquor ratios. More research is carried out on the direct

dyebath reuse (DBR) technology, in which the exhausted dyebath is analysed to determine the concentrations of

remaining dyestuffs and reconstituted to the concentration required for a subsequent dyeing. The advanced

oxidation processes in the wastewater treatment and reuse, particularly the treatments including ozone gas, are

promising in reducing the COD and in the decolorization of the effluent, which further facilitate the reuse of

treated water for a subsequent bleaching, dyeing, finishing and washing processes.

In this work, the recent literature on the minimization of process water and the chemical loads in the textile pretreatment,

dyeing, finishing and printing processes is summarized with particular emphasis on the combined

processes including enzymes and the reuse of the treated effluent by the advanced oxidation processes including

ozone gas. The current legislations concerning the environmental protection are also briefly discussed.