Recycling of pad-batch washing textile wastewater through advanced oxidation processes and its reusability assessment for Turkish textile industry

Water management, recycling, and reuse in industrial facilities is a hot topic in today's growing economy because of declining water levels, regulation pressure, and increasing cost of wastewater treatment and supply. In this study, recyclability and direct reuse of washing/bleaching wastewater from reactive dyeing of cotton fabric through advanced oxidation processes (AOPs) (O3, UV-O3, O3-H2O2, and O3-H2O2-UV) has been investigated. Dyeing trials with treated wastewater were carried out at laboratory scale and no undesirable effects on fabric dyeing quality (ΔE ≤ 1 for color variation) were found for all AOPs. The O3-H2O2-UV process removed COD at a higher rate (55%) than other studied AOPs while color removal was similar (>95%). In pad batch washing/rinsing, 100% water could be recycled (i.e.40% of the total water consumption at facility), reducing fresh water demand for washing operations. Despite this, energy saving, reduced salt consumption and reduction of the cycle time are in favor of recycling/reusing the washing/rinsing effluent.