Environmental and energy analysis of chromium recovery from residual tanned leather using alkaline thermal hydrolysis.

Abstract

The leather industry efficiently uses livestock byproducts but struggles with pollution, especially from chromium in waste. Innovations in chromium recovery can prevent contamination and offer economic benefits, aligning with circular economy principles. However, environmental assessments like life cycle assessment (LCA) are crucial for sustainability. This study evaluates the environmental and energy implications of chromium recovery from leather waste using LCA. Findings indicate that recovering 1 kg of chromium through thermal hydrolysis with an alkaline method results in $ 8.42E-02 resource damage, 4.28E-06 DALY to human health, and 1.60E-08 species year ecosystem damage, according to the ReCiPe method. Sodium hydroxide significantly contributes to environmental damage, highlighting the need for sustainable strategies. With a weighted impact of 201.04 mPt/kg, human health accounts for 62% of the burden, and resource depletion 34%. Recovered chromium reduces environmental damage by 95.65% overall compared to raw production, demonstrating substantial sustainability benefits. The energy assessment shows sodium hydroxide dominates consumption, using 98% of total demand, with 98% from non-renewable sources. Despite energy challenges, chromium recovery reduces environmental impact compared to crude production, promoting ecological resilience.