Effect of ozone, chlorine and hydrogen peroxide on the elimination of colour in treated textile wastewater by MBR

Abstract

In treating textile wastewater, the application of membrane bioreactor (MBR) technology showed high efficiency in COD and BOD5 removal. However, insufficient colour removal was achieved for possible reuse. The aim of the work presented in this paper was to test the performance of chemical advanced oxidation on the elimination of the colour downstream of an MBR. To improve the quality of the membrane bioreactor effluent three different oxidation treatments were tested at lab-scale: ozonation, chlorination and hydrogen peroxide oxidation. Colour, COD and BOD5 were controlled in order to assess the effectiveness of each process. For chlorination, even with 250 mg/L (active chlorine) only 80% colour removal (SACin = 14; SACout = 2.8) was achieved which is considered unsatisfactory. For hydrogen peroxide, the colour removal was even poorer; it was just 10% at a concentration of 250 mg/L. In contrast, good results were obtained by ozonation. By using only 38 mg/L within 20 minutes, it was possible to achieve the reuse recommendation with a satisfactory colour removal of 93% (SACin = 14; SACout = 0.98). The results showed that ozonation was the most promising method.

Advanced treatment of textile wastewater towards reuse using a membrane bioreactor

“…During three phases (6)(7)(8) with VLRs between 1.1 and 3.1 gCOD T /(l day) the COD:N:P of the feed was modified to 100:5:1 through supplementation with NaNO 3 and an equimolar mixture of KH 2 PO 4 and Na 2 HPO 4 (dotted line in Fig. 4).…”

“…This makes MBR technology a highly promising technique for industrial wastewater purification. Therefore MBR effluents can be of a quality suitable for direct recycling or after further purification by additional post-treatment steps [7,8].…”

Sonochemical degradation of naphthol blue black in water: Effect of operating parameters

“…A variety of physical, chemical and biological methods are presently available for the treatment of wastewater discharged from various industries. Conventional methods of the treatment of dye wastewater include adsorption [5], chlorination and ozonation [6,7], electrochemical methods [8,9], biological methods [10,11], chemical oxidation [12,13]. Many advanced oxidation processes (AOPs) were also used for the oxidation of dyes in water [14,15].…”

Environmental impact of polyester and polyamide textiles

“…Rehorek et al (2002) also use a bioreactor with membrane to monitor degradation of azo dyes. Brik et al (2004) investigate effects of ozone, chlorine and hydrogen peroxide on the effectiveness of colour removal in a bioreactor and subsequently (2006) carry out a quantitative evaluation of a bioreactor to allow re-use of textile effl uents to be considered. Koyuncu (2003) incorporates nanofi ltration into a membrane system and investigates optimum conditions for procion dye removal.…”