Comparison of the Sustainability of the Vegetable, Wet-White and Chromium Tanning Processes through the Life Cycle Analysis

Abstract

Public concerns about the quality of life of human beings as well as the quality of natural environments and ecosystems have led to the increasing importance of sustainability for governments and for all industries, including the leather industry. In this context, more "ecological" leather goods are being demanded. It should be noted that this concept is often used without a scientific study to support it. 

This concept of sustainable or ecological product in the field of leather goods, are mainly associated with chrome-free tanneries (that is vegetable and wet-white), but this association should be backed up or dismissed by scientific evidence. A complete scientific study is required, which takes into account the different stages of leather production, including also the treatment of water and by-products, analyzing in a scientific and systematic way the environmental impact of each of these tanning processes. 

This study focuses on the life cycle analysis of the three basic tanning processes: chrome, vegetable and wet-white leather production. It will focus on European manufacturing to have reliable data and reduce uncertainty. 

In the tanning stage, the process with the greatest impact is the vegetable one, to highlight its high impact on global warming at 100 years (GWP100). This result is due to the energy necessary for the production of mimosa and quebracho in addition to the energy for the processing of the leather in the drums. 

Wet white tanning with glutaraldehyde has lowest environmental results than vegetable tanning. 

The chrome tanning process (wet blue) also stands out for its reduced environmental impact. 

Subsequently, to have a global view of the entire production, the LCA of the post-tanning stages must be performed to evaluate the impact of each of the systems studied.