Application of composite construction and demolition debris in heavy metals removal from industrial wastewater

Abstract

The utilization of construction and demolition debris in industrial wastewater treatment by sorption of Co2+ and Ni2+ ions was investigated. Selected waste composites are cost-effective and locally available, still their sorption characteristics and application are not sufficiently investigated. The samples of concrete, facade, ceramic materials, and asphalt were characterized in terms of mineral and surface composition, radioactivity, and stability at different pH values, as well as pH values of suspension and filtrate and electrical conductivity of the filtrate. The sorption capacities were determined in batch experimental conditions in one- and multi-component solutions. Characterization showed different crystal structures and mineralogical compositions of components. The results of gamma spectrometry confirmed the radiological safety of samples. Based on stability testing results, waste materials are suitable for further utilization and do not pose any risk to the environment. The overall sorption results suggested that cement-based materials, in addition to high affinity for the tested ions, represent a sorbent that binds contaminants firmly enough, reduces their mobility and bioavailability, and are suitable for removing Co2+ and Ni2+ ions from wastewaters.