Treatment performance evaluation of chemical oxygen demand from landfill leachate by electro‐coagulation and electro‐fenton technique

Abstract

The removal of chemical oxygen demand (COD) from landfill leachate by electro-coagulation (EC) using iron sacrificial anode has been investigated. The process performance is analyzed in terms of COD removal efficiency and the important costrelated parameters such as electrode and energy consumptions, as a function of initial pH, conductivity, current density, and operation time. The optimum COD removal (65.85%) was obtained with typical operating conditions: current density, 30 mA/cm 2 ; operation time, 180 min; conductivity, 16.4 ms/cm; and initial pH, 6.54. At these conditions, the electrode and energy consumptions during the electrolysis were determined as 0.418 kg COD/kg Al and 11.092 kWh/kg COD, respectively. In addition, the EC and Fenton processes are applied together referred to as the electro-Fenton process in the literature for the removal of COD from landfill leachate and effect of operation time and hydrogen peroxide concentration is examined. The process was very fast in the first 15 min, and then it slowed down till it was complete in 60 min. An optimum COD removal efficiency of 74.21% was obtained at 5000 ppm hydrogen peroxide dosage and 60 min.

Electro-Fenton treatment of mature landfill leachate in a continuous flow reactor

“…Atmaca [9] also employed EF-FeOx method for leachate treatment and obtained 72% COD removal. The similar result (74.21% COD removal) was reported by Orkun and Kuleyin [11]. Mohajeri et al [10] used EF-Fere process where both hydrogen peroxide and ferrous ion were applied into the electrolytic Table 1 The characteristics of landfill leachate.…”

“…In these two applications, hydrogen peroxide was externally dosed rather than continuously electro-generated at a suitable cathode fed with oxygen or air. This is due to the fact that a long treatment time is required for high strength wastewater such as mature leachate (the COD value is as high as several thousand mg/L) when hydrogen peroxide is generated in situ in the latter case [11,12,17,18]. Lin and Chang [6] investigated EF-FeOx method as pre-treatment process in which hydrogen peroxide is externally applied while a sacrificial iron anode is used as ferrous ion source, and 67.3% of COD was removed from the leachate.…”

“…Since 2000, electro-Fenton process has been used for the treatment of mature landfill leachate [6][7][8][9][10][11]. Compared with classic Fenton process, electro-Fenton oxidation could offer significant advantages such as the continuous regeneration of ferrous ion at the cathode and in consequence minimization of sludge production [12,13], and the synergistic effect between electrochemical process and Fenton process [6][7][8].…”

Novel and Conventional Technologies for Landfill Leachates Treatment: A Review

“…However, some studies are discordant and it is clear that distance is also a function of the operating conditions [143]. The disadvantage is that electro-coagulation corresponds to high energy consumption and, therefore, it is necessary to find a compromise between the removal efficiency and consumption of power required [144].…”

Utilisation des procédés électrochimiques et leurs combinaisons avec les procédés biologiques pour le traitement des lixiviats de sites d’enfouissement sanitaires - revue de littérature

“…L'enfouissement est l'un des principaux modes de gestion des déchets dans plusieurs pays du monde (ORKUN et KULEYIN, 2012). Les déchets enfouis subissent divers processus de transformations chimiques et biologiques à l'intérieur de la décharge (KJELDSEN et al, 2002).…”