Decolorisation of exhausted reactive dye bath using ozonator for reuse

Abstract

Exhausted Reactive dye bath samples of Turquoise Blue, Olive Green and Navy Blue shades were collected from cotton knit wear dyeing units in Tirupur. Ozonation was conducted in a column reactor system fed with ozone at the rate of 0.16 g/min to assess its efficiency in reducing the color, chemical oxygen demand and total organic carbon. Complete decolorization of the effluent was achieved in 10 min contact time and ozone consumption of 153 mg/ L for Turquoise Blue, 128 for Olive Green and 143 for Navy Blue shades effluents respectively. The corresponding COD removal was 43 %, 44 % and 43 % for the three shades while TOC removal efficiency was 45 %, 45 % and 40% respectively. The results from the reusability studies indicate that the dyeing quality was not affected by the reuse of decolorized dye bath for two successive cycles. It is concluded that ozonation is efficient in decolorization of exhausted dye bath effluents containing conventional reactive dyes. However, the corresponding removal of COD from the textile effluent was not significant.

Uptake of Indosol Dark-blue GL dye from aqueous solution by water hyacinth roots powder: adsorption and desorption study

“…Removal of these dyes from wastewater is a major environmental challenge, and there is a constant need to have an effective process that can efficiently remove these dyes. Several methods have been employed to remove dye from industrial effluent, such as biological and chemical oxidation, coagulation-flocculation, foam flotation, electrolysis, biodegradation, advanced oxidation, photocatalysis, ozonation (Vandevivere et al 1998;Robinson et al 2001;Papic et al 2004;Forgacs et al 2005;Rahbar et al 2006;Sundrarajan et al 2007). Many of these methods have certain merits but require considerable operational costs (Vandevivere et al 1998;Allen and Koumanova 2005).…”

Textiles wastewater treatment using anoxic filter bed and biological wriggle bed-ozone biological aerated filter

“…Recalcitrant organics include dye, sizing agents and dying aids, leading to wastewater of low biodegradability. Various kinds of treatment processes have been used to treat it, such as biological degradation (Pearce et al, 2003;Novotný et al, 2010), chemical coagulation (Kumar et al, 2008;Mo et al, 2007) and chemical oxidations (Kos and Perkowski, 2003;Sundrarajan et al, 2007;Gulkaya et al, 2006;Radha et al, 2009). Biological methods have been usually applied to remove organics and color of textile wastewater due to its low treatment cost and simple operation and maintenance.…”

Decolorization of Boron-Based Wood Preservatives by Ozonation for Recycling: Optimization of Process Parameters

“…The latter is less selective and predominates under alkaline conditions, while direct oxidation is more selective and predominates under acidic conditions [16,21]. Success in the use of ozone has been reported, not only to treat dye wastewaters to meet effluent standards but also to focus on decolorization of textile industry wastewaters for reuse [11,12,[22][23][24][25]. The application of ozone to treat the color of boric acid-borax solutions that are used as wood preservatives has never been reported.…”