Which treatment procedure among electrocoagulation, biological, adsorption, and bio-adsorption processes performs best in azo dyes removal?

For decades, Which treatment process is the best? has been the primary question for many researchers worldwide. Therefore, this study aims to optimize the treatment models using the Imperialist Competitive Algorithm (ICA) to achieve a techno-economical comparison of biolog-ical, adsorption, electrocoagulation (EC), and bio-adsorption processes as examples in Acid Or-ange 7 (AO 7) and Acid Red 18 (AR 18) removal. Membrane Sequencing Batch Reactor (MSBR), Granular Activated Carbon (GAC), and GAC-MSBR were selected as biological, adsorbent, and biological-adsorption processes, respectively. MSBR was the cheapest (0.02-0.08 US$/m3) fol-lowed by GAC (0.03-0.63 US$/m3). Although MSBR permeates may not be of desirable quality, GAC and GAC-MSBR permeate offer the best quality. In addition to high operating costs in EC (>= 1 US$/m3), the electrodes should be changed after several usages, which cost approximately 550 US$/m3. In this research, GAC-MSBR, as an effective process, had 80-100% AR 18 removal ef-ficiency (0.14-0.16 US$/m3).

Automated summary

This study aims to optimize and compare biological, adsorption, electrocoagulation, and bio-adsorption processes using the Imperialist Competitive Algorithm. The results show that GAC-MSBR is an effective and cost-efficient treatment process.