Serdar Kara

Treatment of winery wastewater by electrocoagulation process

Abstract Winery wastewater treatment by electrocoagulation (EC) process using aluminum (Al) and iron (Fe) electrodes was investigated. The effects of operational parameters such as initial pH, current density and electrolysis time were investigated separately. Chemical oxygen demand (COD), turbidity and color were used to measure the treatment efficiency. Electrode consumptions were calculated per m3 of wastewater. Amount of sludge produced by EC was also reported per m3 of wastewater. The optimum operating conditions were defined due to the initial pH, applied current density and operating time for Fe and Al electrodes. Maximum removal efficiencies were found at pH 7 for Fe electrode and pH 5.2 for Al electrode with current density of 300 A/m2 for both electrodes and with an operating time of 90 min and 120 min for Fe and Al electrodes, respectively. The removal efficiencies were found as 46.6% (COD), 80.3% (color) and 92.3% (turbidity) for Fe electrode while they were 48.5% for COD, 97.2% for color and ...

Preventing of Cathode Passivation/Deposition in Electrochemical Treatment Methods – A Case Study on Winery Wastewater with Electrocoagulation

Electrochemical methods and processes have been applied for many years in environmental applications such as water/wastewater treatment, recovery of metals, electroplating and qualitative/quantitative analysis in various aqueous media. Among these processes, electro‐ coagulation (EC) has gained many interest due to providing simple, reliable and cost effective operation for the treatment of wastewaters without and need for additional chemicals, and thus the secondary pollution. EC is declared an environment-friendly technique since the ‘electron’ is the main reagent and does not require addition of the reagents/chemicals. This will minimize the sludge generation to a great extent and eventually eliminate some of the harmful chemicals used as coagulants in the conventional effluent treatment methods. EC process can effectively destabilize small colloidal particles and generates lower quantity of sludge compared to other processes [1]. This technique uses a direct current (DC) source between metal electrodes immersed in polluted water [2]. In this method, soluble metal electrodes (such as iron and aluminium mostly) form metal hydroxides when subjected to a suitable current. The metal hydroxides act as coagulants and lead to the removal of various contaminants [3]. The pros and cons of the EC are tabulated in Table 1

Container washing wastewater treatment by combined electrocoagulation–electrooxidation

ABSTRACT Treatment of container washing wastewater (CWW) by using combined electrocoagulation (EC)–electrooxidation (EO) process was studied. CWW contains many organic compounds such as surfactants used in cleaning agents. Wastewater was first treated by EC with iron (Fe) and aluminum (Al) electrodes. The process performance was measured according to the removal efficiencies of soluble chemical oxygen demand (sCOD) and color. Maximum sCOD removal efficiency was found 82% and color removal efficiencies were 95%, 95% and 98% at 436, 525 and 620 nm, respectively, with Fe electrodes under 25 mA/cm2 current density, initial pH of 5 and 120-min operation time. Because of the low sCOD removal efficiency, EO was used as post-treatment process by using boron doped diamond electrode (BDD). sCOD removal efficiency was increased to 89% and color removal efficiencies decreased to 72%, 64%, 71% at 436, 525 and 620 nm, respectively, under 25 mA/cm2 current density, initial pH of 3 and 300-min operation time. This study showed that electrochemical processes caused new complex molecules formation in the CWW, which caused deterioration of water color and limited the process efficiency.