The effect of pre-ozone oxidation on acute toxicity and inert soluble COD fractions of a textile finishing industry wastewater.
The present work evaluates pre-ozonation for removal of acute toxicity, color and COD as well as reduction of inert soluble COD fractions in two wastewater samples (S1 and S2) taken from a textile finishing industry, located in Istanbul (Turkey). The wastewater samples were oxidized at original pH of 8.6-8.8 under 18.5-24 mg/L of applied ozone doses. Acute toxicity was monitored using Daphnia magna. The results showed that pre-ozonation improved the biodegradability and reduced the acute toxicity. Acute toxicity in raw wastewaters was reduced by 80-90% using 129-200 mg/L transferred ozone (TrO(3)) concentrations. At this point, 86-96% of color, 33-39% of soluble COD and 57-64% of total COD were removed from wastewaters. Both color and COD parameters were found related to the acute toxicity of the wastewater. Pre-ozonation decreased the inert soluble COD fraction (S(I)) of raw wastewater while soluble product formation (S(P)) increased slightly (5-10 mg/L). However, residual COD (the sum of S(I) and S(P)) remained below discharge limit.
Environmenntal Engineering Department, Pamukkale University, Kinikli/Denizli, Turkey.
Hüseyin
H
Selçuk
Gulen
G
Eremektar
Süreyya
S
Meriç
D000818:Animals; D003116:Color; D003621:Daphnia; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D008956:Models, Chemical; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D010126:Ozone; D013783:Textile Industry; D013997:Time Factors; D014421:Turkey; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
D007220:Industrial Waste; D010126:Ozone; D010100:Oxygen