Minimization of the environmental impact in the unhairing of bovine hides

This study tests an alternative method to the traditional unhairing method used during the process of tanning the hides. The new method is based on the substitution of sodium sulfide by hydrogen peroxide as an unhairing agent in both hair recovery and recirculation of the floats employed in the proc...

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Detalles Bibliográficos
Autores: Morera Prat, Josep M., Bacardit i Dalmases, Anna, Ollé i Otero, Lluís, Bartolí, Esther, Borràs Fillat, Maria Dolors
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2008
País:España
Institución:Universitat de Lleida (UdL)
Repositorio:Repositori Obert UdL
OAI Identifier:oai:repositori.udl.cat:10459.1/71298
Acceso en línea:https://doi.org/10.1016/j.chemosphere.2008.05.023
http://hdl.handle.net/10459.1/71298
Access Level:acceso abierto
Palabra clave:Hide unhairing
Unhairing wastewater
Tanning industry
Residual float
Pollution minimization
Descripción
Sumario:This study tests an alternative method to the traditional unhairing method used during the process of tanning the hides. The new method is based on the substitution of sodium sulfide by hydrogen peroxide as an unhairing agent in both hair recovery and recirculation of the floats employed in the process. The properties of the hides obtained using the two methods have been compared and the results indicate that those hides have similar physical, chemical, and organoleptic properties. However, the differences existing from an environmental point of view are significant. These include reductions of water consumption (approx 70%), chemical oxygen demand (approx 35%), toxicity (98%) and total kjendhal nitrogen (50%). Also, the risk associated with the production of hydrogen sulfide is eliminated, which implies a great improvement in terms of safety for the workers. Given the large amounts of water and chemical pollution discharged in the process, the reductions in absolute values represent a significant improvement. A financial assessment was carried out to demonstrate that the proposed new system is 16% more economic than the traditional one.