Heavy metal removal from wastewater by pellet reactor

Abstract

Wastewater from plating industry with high concentration of heavy metal has been concerned as a serious problem for environment. Therefore, it is necessary to find an efficient method to treat this kind of wastewater before being discharged into the environment. In this paper, the aim was to evaluate the feasibility of a  pellet reactor  to treat the plating wastewater. The hydraulic retention time, the initial pH and molar ratio of carbonate to heavy metal was investigated to optimize the heavy metal removal efficiency in the pellet reactor. The results showed high removal efficiency in the pellet reactor could be achieved 65%, 71% and 67% of Zn²⁺, Cd²⁺ and Cu²⁺ with ratio of CO₃^2-/metal of 2.5, flow meter of wastewater of 16 L/h, initial pH of 9.5, the mass of sand of 50 gram. After pellet reactor treatment, the seeding materials was analyzed with SEM microphotograph and elemental analysis to see the different morphology, element atomic percentage of the sand before and after pellet reactor.