Scale-up testing for reducing pollution load of chemicals in wastewater of leather post-tanning

The leather industry has been looking for alternatives to minimize its environmental impacts, including studies to reduce the pollution load of liquid effluents from the leather process. Although studies reducing the supply of chemicals have already indicated optimized offers of fatliquoring and retanning agents, the effect of the scale-up of these optimized conditions on effluents and the quality of the leather remains unknown. This study aims to reduce the pollution load of post-tanning effluents by reducing leather chemicals supply. Tests were performed on pilot and industrial scales, reducing the offer of retanners and fatliquors in two levels: 19% and 26%. The effluents were tested for pH, conductivity, dissolved solids, sulfate, biochemical oxygen demand, and chemical oxygen demand. The leather was tested for organoleptic properties and physical-mechanical tests. The reduction of chemicals allowed the depletion of the raw wastewater pollution load. The leather obtained showed a quality within the established standards. Besides, post-tanning formulation costs were reduced by 24%. (c) 2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Automated summary

This study aimed to reduce the pollution load of post-tanning effluents by reducing the supply of leather chemicals. The results showed that reducing the chemicals supply could decrease the pollution load of raw wastewater and produce high-quality leather that meets established standards.