Systematic assessment of electrocoagulation for the treatment of marble processing wastewater

Abstract

In this study, the treatability of marble processing wastewater by electrocoagulation using aluminum and iron electrodes was investigated. The sample used was from the marble-processing plant in Sivas and its turbidity, suspended solids, chemical oxygen demand and total solids concentrations were about 1,914 NTU, 2,904, 150 and 4,750 mg/L, respectively. The effects of various operating parameters such as initial pH, current density and electrolysis time on turbidity, suspended solids, chemical oxygen demand and total solids removal efficiencies were investigated. The settling characteristics of waste sludge produced and energy and electrode consumption were also determined. The optimum values of initial pH, current density and electrolysis time in electrocoagulation studies carried out using aluminum electrode were found to be 7.8, 30 A/m 2 and 5 min, respectively. Under these conditions, the removal efficiencies obtained for turbidity, suspended solids, chemical oxygen demand and total solids were 98.5, 99.2, 55.2 and 92.4 %, respectively. Corresponding energy and electrode consumptions were 0.143 kWh/kg SS and 0.010 kg Al/kg SS. For iron electrode, the optimum parameter values were found to be 7.8 pH, 20 A/m 2 and 5 min, respectively. Under these conditions, removal efficiencies for turbidity, suspended solids, chemical oxygen demand and total solids were determined as 94.3, 99.1, 54.2, and 96.1 %, respectively. Energy and electrode consumptions were 0.0571 kWh/kg SS and 0.0206 kg Fe/ kg SS, respectively. Settling characteristics of sludge produced during experiments carried out using both aluminum and iron electrodes were fairly good. The results showed that electrocoagulation method can be used efficiently for the treatment of marble processing wastewater under proper operating conditions.

Feasibility of electrocoagulation/flotation treatment of waste offset printing developer based on the response surface analysis

“…Here, use of iron electrode combinations resulted in a greenish effluent, color of which changed into yellow along the ECF process, emphasizing that the electrode provides an extra turbidity loading into the effluent. The forming of greenish and yellow effluent after the process might be originated due to the Fe 2+ and/or Fe 3+ ions dissoluted from the surface of the electrode (Solak et al, 2009;Chen et al, 2000;Kobya et al, 2006;Ozyonar and Karagozoglu, 2012). The copper removal efficiency increased from 29.4% to 100% for the Al(À)/Al(+), from 17.2% to 99.3% for the Al(À)/Fe(+), from 13.0% to 96.5% for the Fe(À)/Fe(+), and from 8.5% to 94.7% for the Fe(À)/Al(+) at a current density of 4 mA cm À2 and interelectrode distance of 1 cm (Fig.…”

Electrolyte Addition for Enhanced Wastewater Treatment by Electrolysis using Cu Electrode

“…Biological nutrient removal (BNR) has been commonly used for the removal of nutrients from wastewater. However, this method has disadvantages such as operating complications by internal sludge and nitrate recycling, continuous need of air supply, high operating costs, sensitivity to shock toxic loadings, longer reaction time for the treatment, and high sensitivity of microorganisms to pH and temperature [2].…”

“…With the strict environmental regulations regarding wastewater discharge in recent years, electrochemical technology has been widely utilized in the treatment of various types of wastewaters such as textile [4][5][6], oil and oil-in-water emulsion [7][8][9], laundry [10][11][12], livestock [13][14][15], leachate [16][17][18], and sewage [2,[19][20]. The use of electrochemical technology provides several benefits, such as strong oxidation, easy operation, no limitation by a seasonal variation, variable capability to influent flux and quality, and rapid treatment time, over the conventional wastewater treatment methods.…”

Simultaneous application of iron and aluminum anodes for nitrate removal: a comprehensive parametric study

“…Recently, EC has been used in removing nitrate (Lakshmi et al 2013) and other pollutants such as lead (Kamaraj et al 2013) as well as treatment of wastewaters (Ozyonar and Karagozoglu 2012;Sridhar et al 2013). Many studies were carried out the removal of nitrate by EC process using iron and aluminum anodes separately (Lacasa et al 2011;Lakshmi et al 2013).…”