Economic Viability of Removal of Heavy Metal Cations from Industrial Wastewater Using Innovative Technique

1 Member (ASCE/EWRI), Environmental Engineering PhD Program, The American University in Cairo, P.O. Box 74, New Cairo 11835 2 Director of Egypt Solid Waste Management Center of Excellence, Ain Shams University, 1 El-Sarayat St., Abassia, Cairo 11517 Egypt. 3 Chair of the Department of Mechanical Engineering, The American University in Cairo, P.O. Box 74, New Cairo 11835, Egypt. Corresponding Author: Mohamed El Zayat _________________________________________________________________________________________ Abstract Cement Kiln Dust (CKD) is experimented in dynamic up-flow fixed bed reactors using stainless steel columns to study the dynamic breakthrough patterns. Synthetic metal solutes containing the target metals (lead, copper, and cadmium) are fed with an initial concentration of 30 mg/l. The experimental runs show that the CKD has a high affinity to adsorb the target metals. The surface concentration at exhaustion in a molar basis is found to be 240 μM/g, 290 μM/g, and 650μM/g for lead, copper and cadmium, respectively. A pilot scale of 20~25 l/hr capacity is fabricated to investigate the capability of CKD in treating industrial wastewater. Raw industrial wastewater from glass manufacturing is introduced to the pilot scale unit. The proposed treatment unit using CKD is able to reduce the total suspended solids (TSS) by 95% and biological oxygen demand (BOD) by 72%. Moreover, heavy metals concentrations in the raw wastewater have been effectively treated to comply with international guidelines for restricted irrigation. The results are promising and indicating that the introduced methodology can be industrially applied. Finally, the economic indicators in terms of economic rate of return (11.5%) and the positive net economic present value prove that the system is economically viable. Accordingly, it is apparent from this study that CKD can be used in an innovative and compact treatment technique to recover industrial wastewater from heavy metals. __________________________________________________________________________________________