Reusing copper tailings in concrete: corrosion performance and socioeconomic implications for the Lefke-Xeros area of Cyprus

Abstract

Copper mining and processing activities at an abandoned mine in the Lefke-Xeros area of Cyprus have created a huge environmental contamination problem in the locality. As an alternative mitigation and management measure, we reported in previous studies that these tailings could be used as a concrete making material. In this paper, results of an experimental investigation of the reinforcement corrosion performance and cost efficiency of 0.57 and 0.50 w/b ratio concrete containing copper tailings either as a cement replacement or an additive material are presented. The time to initiation of corrosion and half-cell potential (HCP) of reinforcements were measured. Actual corrosion status of extracted reinforcement bars was also verified by visual inspection. Results showed that while early corrosion initiation occurred in some samples containing tailings as a cement replacement material, delayed corrosion initiation was observed in all samples containing copper tailings as an additive. Although HCP values became slightly more electronegative as tailings content of samples increased, no substantial reinforcement corrosion was observed. Based on corrosion performance and cost efficiency analyses, utilization of 5% pre-wetted tailings either as a cement replacement or an additive material is the best tailings reuse approach. Increased tourism-related businesses associated with reduced pollution of the Lefke-Xeros coastal area would have a positive impact on the socioeconomic status of the community.