Enhancing water efficiency and wastewater treatment using sustainable technologies: A laboratory and pilot study for adhesive and leather chemicals production

•Leather and adhesive chemical industry generates a huge amount of effluent.•Using the best available options for water conservation reduced wastewater generation.•EC treatment is a suitable option for wastewater with low electrolytes.•HSSF CWs treatment is the alternative option for wastewater with high electrolytes.•Reuse after treatment produced near ZLD in leather chemical production industry.