Influence of solids on the removal of emerging pollutants in electrooxidation of municipal sludge with boron-doped diamond electrodes

Electro-Oxidation in Combination with Biological Processes for Removal of Persistent Pollutants in Wastewater: A Review

“…It is possible to apply EOP over short periods of time, mostly of between 60 to 120 min, which translate into small space requirements. However, retention time depends on several factors, namely: complexity of the effluent, water quality requirements, current density/intensity applied and the material of the electrode [8,52,53].…”

“…Additionally, many POPs and EPs can become adsorbed on solids, which reduces the possibility of them getting in contact with electrogenerated •OH. Barrios et al [8] evaluated the performance of an EO process with BDD electrodes to treat sludge with a concentration of 0.8% and concluded that the low degradation of non-phenols and triclosan was due to the fact that >98% of these compounds remained associated (adsorbed) to solids. Efi Kotta [80] found a decrease in the efficiency of the treatment of organic matter due to the presence of high concentrations of solids (80 g/L) in the industrial effluent of olive bleached pulp, in addition to the Fig.…”

“…[38] represented in equations 7 and 8 can be applied. ( 7) (8) Where j lim is the limiting current density (A/m 2 ), A (m 2 ) is the area of the anode, V (m 3 ) is the volume of treated wastewater, k m is the mass transport coefficient in the electrochemical reactor (m/s), COD is the chemical oxygen demand at a given time and F is the Faraday constant (C/mol).…”

“…Of the above, EO is the most studied process due to its several advantages such as: environmental compatibility, versatility, energy efficacy, amenability to automation, and high efficacy in destroying POPs and EPs in water, wastewater and sludge [2] [8]. EO has been studied along with several effluents, most notably: tannery [9], electrical industry [10], coke production [11], dyes [12] and hospitals [13].…”

Emerging Pollutants – Part II: Treatment

“…The degradation efficiency of pollutants by different electrode materials, including boron-doped diamond (BDD), mixed metal oxide (MMO), platinum electrode, and high voltage sparks (HVS) were investigated.The results showed that in 60 min, more than 85% of majority of the pollutants could be degraded by BDD and MMO electrodes, while overall degradation efficiencies by platinum electrode and HVS were low. Moreover, in a complex matrix of wastewater samples, degradation efficiencies by BDD electrode could reach 70% Barrios et al (2016). studied the electrooxidation of waste activated sludge (WAS) with boron-doped diamond (BDD) anodes for removing three emerging pollutants, including triclosan, bisphenol A, and nonylphenols.…”