Leather manufacturing by using treated municipal wastewaters

Leather processing requires copious amounts of freshwater, approximately between 15 and 20 L per kg of raw hide. The possibility of reusing reclaimed municipal wastewaters in the leather production assumes a great significance, proving a sustainable solution to the conservation of the groundwater reserves. In the present work, a combination of a membrane bioreactor (MBR) and nanofiltration (NF) membrane processes was investigated for the municipal wastewater reclamation, and their performances were evaluated and designed to meet water quality criteria required by the wet stages of tanning process. The results showed that the municipal wastewaters treated by combing MBR and NF met the required quality criteria in terms of total/permanent hardness, Fe, Mn and ammonium contents. The quality of the leathers produced both on pilot and industrial scale using treated water did not show any significant difference in terms of physical and technical properties, and satisfied fully the tannery specifications.