Optimizing the SART process: A critical assessment of its design criteria

•The current design criteria of the SART process have been challenged, based on an experimental study.•Copper conversion can be achieved with optimal conditions of pH 4.25–4.5 and sulfide excess of 5–10%.•Copper conversion can be controlled by ORP measurements in line.•It is necessary only 1 min of residence time to reach maximum copper conversion.•Current settling parameters could be oversized and flocculant addition could be avoided.