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High levels of organic pollutant containing industrial wastewaters which are generated during the production of vegetable oils must be treated before discharge to the receiving environments. In this work, treatment of sunflower oil industry wastewater was performed via coagulation-flocculation, electro-Fenton and sequential operation of these two methods. To determine optimum coagulant concentration, flocculant concentration and pH, coagulation-flocculation studies were carried out under 4, 10, 16 g/L PACl and Al2(SO4)3.18H2O coagulant concentrations, 0.06, 0.18, 0.3 g/L anionic commercial polyelectrolyte concentrations and 4, 6, 8 pH values, respectively. Results showed a COD removal of 97% under optimum conditions of 10 g/L Al2(SO4)3.18H2O, 0.06 g/L flocculant concentration and pH 6. Electro-Fenton studies were performed under 1, 2.5, 4 A current intensity, 4.5, 9, 18 g/L FeSO4.7H2O concentration, 32.71, 81.77, 130.84 mM H2O2 concentration, and 3, 5.5, 8 pH conditions. Optimum operating conditions for electro-Fenton method were obtained as 1 A, 9 g/L FeSO4.7H2O, 130.84 mM H2O2, 6.06 H2O2/Fe2+ molar ratio and pH 3. Treatment under optimum conditions revealed 99% COD removal and 2.37 kWh/m3 energy consumption for electro- Fenton method. Sequential coagulation-flocculation-electro-Fenton method under optimum conditions resulted in 98% COD removal and 0.48 kWh/m3 energy consumption at 15 min operation, thus the treated water is dischargeable since COD value (183 mg/L) is below discharge limits. [ABSTRACT FROM AUTHOR]

In this work, effects of agitation speed, inoculum ratio, initial substrate concentraion and incubation temperature were investigated for anaerobic biohydrogen production. The most suitable parameters were determined as agitation speed 200 rpm, microorganism inoculum ratio 1:10 v/v, initial substrate concentration 32.4 g COD/L and temperature 37°C. Under these conditions, 1257 mL H2 production, 17.06 mL H2/g COD yield and 6.441 mL H2/L maximum H2 production rate was reached. For first order elementary reaction rate model, reaction rate constants were calculated as 6.5x10-5 min-1 and 7.92x10-5 min-1 for temperatures of 28°C and 37°C, respectively. Arrhenius constant and activation energy were calculated as 9.74x1034 min-1 and 229.20 kJ/mol respectively. For Michaelis- Menten model, maximum H2 production rates, Michaelis constants and R2 values were calculated as 11.47 mL H2/L.min, 74.66 mL H2/L.min, 181.9 g COD/L, 447.7 g COD/L and 0.9458, 0.9505 for 28ºC and 37°C temperatures, respectively. Using modified Gompertz model, all R2 values were obtained greater than 0.99, maximum H2 production potentials were found as 2.126 L H2/L, 2.777 L H2/L at 28°C and 37°C with 32.4 g COD/L, respectively. Maximum H2 production rate was reached as 15.250 mL H2/L.min at 37°C and 27 g COD/L initial substrate concentration. [ABSTRACT FROM AUTHOR]