Organic halides removal from dye wastewater

Wastewater originated from reactive dye processes represent a specific ecological problem due to its high content of organic halides and color besides. This type of wastewater is characterized by poor biodegradability, therefore some other treatment method should be applied prior to discharge to the sewage system. In our previous investigations coagulation/flocculation process was successfully applied as a treatment method for reactive dye wastewater decolorization. In this work, the possibility of application of AOX method in monitoring efficiency of flocculation process, detecting and measuring presence of organic chlorine in reactive dye wastewater, was investigated. Experiments, in laboratory scale, were carried out in wastewater from synthesis of anthraquinone reactive blue monochlorotriazine dye, similar to C.I. Reactive Blue 5, and model wastewaters of other representative of monochlorotriazine reactive dyes (C.I. Reactive Red 45, C.I. Reactive Green 8, C.I. Reactive Blue 49 and C.I. Reactive Blue 137). The results have shown that AOX values, as well as GOD, BOD5, TOC and IC50 parameters were significantly reduced. Quality of water obtained after treatment process is suitable for discharge to the sewage system.