Original scientific paper

Impact of electrode materials and current intensity on the efficiency of oily wastewater treatment using electrochemical procedures

Morana Drušković orcid.org/0000-0002-3745-8002 ; Indeloop d.o.o., Slavonska avenija 22 G, Zagreb, Hrvatska
Dražen Vouk ; Sveučilište u Zagrebu, Građevinski fakultet Fra Andrije Kačića-Miošića 26, Zagreb, Hrvatska
Mario Šiljeg ; Sveučilište Sjever, Geotehnički fakultet Hallerova aleja 7, Varaždin, Hrvatska
Robert Kolar ; Indeloop d.o.o., Slavonska avenija 22 G, Zagreb, Hrvatska
Karlo Nađ orcid.org/0000-0002-2939-2672 ; Institut Ruđer Bošković, Zavod za eksperimentalnu fiziku Bijenička cesta 54, Zagreb, Hrvatska

Abstract

The paper examines the efficiency of a hybrid electrochemical procedure with electrodes made of iron, aluminium, stainless steel and carbon in the treatment of oily wastewater of mineral origin. The impact of current intensity on the efficiency of the applied treatment process is also examined. Oily wastewater in the paper is generated in a syngas treatment system (wet scrubber) within the pilot gasifier of sludge from a wastewater treatment plant. In order to optimise the process, the paper examined the impact of electrode types connected in series and their combinations on the efficiency of the removal of individual water quality indicators. The purpose of the examination was to achieve a satisfactory efficiency of the removal of total hydrocarbons, mineral oils, chemical oxygen demand (COD) and total organic carbon (TOC) from oily wastewater. The wastewater that is the subject of this research is characterised by high concentrations of COD (2200 mg/L), total hydrocarbons (150 mg/L) and a pH value of about 9.0. Stainless steel electrodes proved very efficient in the removal of COD (over 70%) and total hydrocarbons (over 65%). Iron and aluminium electrodes showed a lower efficiency, i.e. 25% and 11%, respectively. A serial connection of treatment phases (reactions) using stainless steel, iron and aluminium electrodes connected in series resulted in the removal of total hydrocarbons of 99.9%, COD of 96% and TOC of 73%.

Keywords

oily wastewater, wet scrubber, electrochemical treatment procedures, electrodes, current intensity, COD, TOC, total hydrocarbons, mineral oils

Hrčak ID:

315429

URI

https://hrcak.srce.hr/315429

Publication date:

29.6.2023.

Article data in other languages: croatian german

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