Abstract

Removal of Notorious Heavy Metal and Harmful Microbes from Industrial Wastewater using the Modified Fourth Generation Downflow Hanging Sponge Reactor

Abdou Saad El-Tabl, Karem. S. Sarhan and Ahmed Behery

Chemistry Department, Faculty of Science, Menoufia University, EGYPT.

ABSTRACT

Notorious heavy metals, organic wastes and harmful microbes have become one of the most serious environmental problems today. In recent years, various methods for heavy metals and organic wastes removal from industrial wastewater have been extensively studied. This paper reviews the current methods that have been used to treat heavy metals in industrial wastewater and evaluates the techniques. The order of cost effectiveness is adsorption, evaporation, aerobic, anaerobic, ion exchange, electro dialysis, micro – and ultra-filtration, reverse Osmosis, precipitation, distillation, oxidation, solvent extraction. It was observed that, the above methods have some limitations. Modified Downflow Hanging Sponge (DHS) reactor will be a good water treatment technology in the near future, it was used for excellent removal of notorious heavy metals, organic pollutants and harmful microbes, and the reactor has advantages like low cost, ease of use and satisfaction level. In order to achieve these objectives, treatment scheme has been investigated. It consists of mixing a chelator with wastewater in different concentrations followed by a Downflow hanging sponge (DHS) reactor. The main objective of the present study was the removal of notorious heavy metal ions, namely Cu(II), Zn(II), Fe(III), pb(II) and Cr(III).The results revealed that, the efficiency of heavy metals removal at 35º C after 30 min in the presence of 1.4 gL-1 of the chelator are 85% for Cu(II), 65% for Zn(II), 72% for Fe(III), 61% for Pb(II), 64% for Cr(III). The results show that removals of fecal coliforms were achieved. From the results of DHS effluent, fecal coliforms decreased from 4.5x106 to 2000 and the overall removal efficiency of fecal coliforms is (99.8%).

Keywords :DHS reactor, organic chelator, notorious, heavy metal, fecal coliforms.