Khalid Bani-Melhem

Enhancement of COD-Nutrients Removals and Filterability of Secondary Clarifier Municipal Wastewater Influent Using Electrocoagulation Technique

The present work studied experimentally the variations of some characteristics of the mixed liquor solution in wastewater treatment plants (WWTPs) under the effect of electrocoagulation (EC) technique. Unlike conventional methods, electrocoagulation was performed using cylindrical perforated iron electrodes to achieve a good distribution of the applied DC field onto the municipal wastewater. Effects of electrocoagulation time, applied voltage gradient, and aeration on the mixed liquor characteristics were considered. The study figured out the dependency of the local pH and oxidation potential reduction (OPR) values, near anode and cathode on these operational conditions. It was found that electrocoagulation process reached steady state conditions in no more than 60 minutes. At high voltage gradient (6 V/cm), the steady removal efficiencies of COD and nutrients exceeded 89%. While aeration showed moderate influence on removal efficiencies and wastewater sludge filterability, it significantly affected the pH and ORP near the electrodes especially at the low voltage gradient. Results also indicated that the sludge filterability was improved notably by increasing the voltage gradient to have minimal levels of specific-resistance to filtration (SRF).

Reduction of COD and TSS from Paper Industries Wastewater using Electro-Coagulation and Chemical Coagulation

The objective of the present study was to investigate experimentally the removal of total suspended solid (TSS) and chemical oxygen demand (COD) of wastewater from paper industries by electro-coagulation techniques solely, or with the aid of chemical flocculants. Electro-coagulation experiments were carried out using iron electrodes and either iron sulphate or calcium carbonate as chemical coagulants. A parametric study including the effect of the type of coagulant, initial pH, current density (CD), circulating flow rate, and electro-coagulation time, on the percent removals of TSS, and COD was considered to explore their role in improving the treatment performance. Without the aid of flocculants, electro-coagulation treatment was able to reduce TSS and COD concentrations up to 80%. In particular, electro-coagulation with the aid of iron sulphate or calcium carbonate as flocculants was found to have the highest removal levels that reach values in the range of 90–97%.

A Theoretical Study on Municipal Solid Waste Characterization in Jordan and Its Economic Feasibility

During the last few years, the municipal solid waste (MSW) has increased dramatically in Jordan as a result of the rapid population growth.