Application of electrodialysis for the treatment of almond industry wastewater

Abstract

In this work, electrodialysis has been proved to be a suitable technique for decreasing the conductivity of a real wastewater from an almond industry, which has been previously treated by electrocoagulation (EC) and electrooxidation (EO). A seven-cell electrodialyzer, with total active membrane area of 1400 cm 2 , was employed and several parameters, as the limiting current density, were determined. A method for measuring voltage across the membranes was developed, in order to control membrane fouling. The method consisted of capillaries inserted into the solution compartments and connected to a high impedance voltmeter. A study of the reuse of the concentrate solution was made, and it was stated that it can be concentrated ten times. The treatment of the wastewater was performed at different voltages (7-16 V) to reach values of conductivity of the diluate of 0.5 mS cm -1 . After that, the scaling up to a pre-industrial scale was performed by using a seventy-cell electrodialyzer, with total active membrane area of 3.5 m 2 . The process was performed by applying voltages of 20-70 V and a final conductivity of the diluate of 0.5 mS cm -1 was achieved. The electric energy consumption was calculated in every case.2

Application of Electrodialysis Process for Reduction of Electrical Conductivity and COD of Water Contaminated By Composting Leachate

“…PO4-P and NH4-N) from effluents [8,9,22,23,25] and desalination [9,15,26,27]. ED can also be implemented for the treatment of industrial wastewater [17,28] such as reducing electrical conductivity from almond industry [29], chloride removal from wet flue gas desulfurization wastewater [28], or removal of harmful ions such as F -, NO3 -, CLand Brand heavy metals such as pb 2+ , Ni 2+ , Cu 2+ , Cr 3+ , Mn 2+ , Fe 3+ , etc. [31,32].…”

Current to Clean Water – Electrochemical Solutions for Groundwater, Water, and Wastewater Treatment

“…After ED treatment, the diluate contained close to zero nickel ions [36]. Other authors also report high removal efficiency of heavy metals with ED treatment [37 -41] and for desalination [41,42] The ED process depends on several parameters, e.g., applied voltage or current, conductivity, pH, and concentration of the electrolyte [53]. The performance and lifetime of ED modules are affected by scaling and fouling phenomena of IEMs due to low solubility of some salts, organic substances, and colloidal particles of the influent [17].…”

“…After ED treatment, the diluate contained close to zero nickel ions . Other authors also report high removal efficiency of heavy metals with ED treatment and for desalination , . In Tab.…”

A Review of Promising Electrocoagulation Technology for the Treatment of Wastewater

“…The coagulant performed a similar function as the electrodes, neutralizing the charge of the particulates, thus allowed them to collect and settle at the bottom of the tank. In addition, electrocoagulation-flotation is talented of reducing waste production, time and electrical energy consumption for wastewater [7] [8] [9] while [10] and [11] enhanced electrocoagulation device for treating various types of industrial wastewater and observed how electrocoagulation-flotation(ECF) reactor can be effective, according to wastewater type, pH, current density and type of metal electrodes (aluminum, steel). Among all the various technologies available, electrolysis is one of the best.…”