TANNERY WASTE VALORIZATION THROUGH ENZYMATIC HYDROLYSIS: A ZERO-DISCHARGE APPROACH TO PROTEIN RECOVERY AND CHROME-FREE RE-TANNING IN LEATHER PROCESSING

The leather industry is under increasing pressure to adopt sustainable practices due to its generation of high volumes of hazardous solid and liquid waste, particularly chrome-laden shavings and protein-rich sludge. This paper explores the application of enzymatic hydrolysis for the valorization of tannery solid waste as a zero-discharge approach. Emphasis is placed on the recovery of hydrolyzed proteins for reuse in chrome-free re-tanning processes, thereby promoting circularity and reducing environmental burden. The literature and recent developments in biocatalysis and process engineering, this study provides a framework for integrated tannery waste valorization. Graphical models, tables, and process flow diagrams illustrate technical pathways and economic feasibility for industrial adoption.