Municipal Wastewater Reclamation and Reuse in the Leather Industry

In the present work, an integrated pilot scale membrane system (membrane bioreactor (MBR) - nanofiltration (NF)) was applied for the treatment of municipal wastewater to produce reclaimed water. Its performance was evaluated and designed to meet water quality requirements for use in the tanning process. The feasibility of using reclaimed wastewater in the different wet phases of the tanning process (beamhouse, tanning, re-tanning, dyeing, fatliquoring) was investigated on pilot scale for manufacturing of chrome tanned leathers. The results showed that the combination of MBR and NF processes applied to municipal wastewaters was adequate for recovering water with low hardness, very low Fe, Mn and ammonium levels as required by tanneries. The pilot-scale tanning tests demonstrated that there were no significant differences between the wet-blue (chrome-tanned) leathers produced using treated wastewater and those produced using softened tap water in terms of physical and sensorial properties. Hence, the suitability of the treated water for use in the tanning was verified and validated.