ABSTRACT

This study is intended to find the optimum operational conditions for the recovery of caustic (NaOH) solution from mercerization in textile process. For this, the silt density index (SDI) of ceramic membranes, the fouling property of NF membranes, the optimum conditions for the membrane regeneration through chemical cleaning, the optimum removal conditions of total organic carbon (TOC), turbidity, color and the permeate flux through the membranes were investigated. As a result, a combined membrane process using ceramic membrane (first step) and polymeric membrane (second step) was found to be suitable for the removal of total suspended solid (TSS), residual organics, turbidity including color and the recovery of caustic solution from wastewater caustic stream in mercerization process. The permeated caustic solution can be reused, which could offer economical benefits through the reduction of chemical use and the cost of wastewater treatment.