Improvement of COD and TOC reactive dyes in textile wastewater by coagulation chemical material

Abstract

This study was designed to investigate the removal of reactive dyes, Samofix Red V-RBL and Samofix Green V-G from wastewater using a two step Al (III) coagulation/activated carbon adsorption method.
The effects of pH and coagulant dosage as well as the effects of contact time and a powdered activated carbon dosage on dye removal were studied. The process was optimized with reasonable consumption of coagulant and quantity of obtained sludge. Coagulation as a main treatment process followed by adsorption achieved almost total elimination of both dyes from wastewater with significant reduction (90%) of chemical oxygen demand (COD), total organic carbon (TOC) and absorbable organic halide (AOX). Besides high efficiency of dye removal, the combined treatment process offers many advantages for potential application such as coagulant savings, minimal amount of sludge formation
and also an economic feasibility since it does not require high costs for chemicals and equipments.