Abstract

In a growing environmental concern on reducing greenhouse gas emissions (GHGs) as well as achieving United Nations (UN) sustainable development goals (SDGs), the development of a suitable methodology for the assessment of carbon footprint (CFP) for process industries such as leather is necessary. In this regard, a systematic approach, considering the energy requirements of various unit operations of a mechanical nature in leather processing, within a tannery and their contribution towards CFP has been presented for the first time. Estimation of CFP for the raw skin/ hide to finished leather process has been performed using USA Energy Information Administration (EIA) data, incorporating respective power consumption (kWh) values for the whole process, with unit operations or stages, comprising mechanical or machinery operations and considering two types of power plant: coal and natural gas. Processing types such as Raw-Finished, Raw-Wet blue, Wet blue- Finish have been considered for skins and hides. Calculation of CFP has been performed for a typical tannery processing a capacity of 600 sides or 2000 skins per day. The results show that, 0.29 and 0.77 kW average total energy consumption respectively per kg of raw hide and skin for processing to finished leather. The total CO2 emissions (kg) have been calculated as 0.3 and 0.78 kg, respectively for per kg of hide or skin processed to finished leather; or in terms of area of leather, 0.16 and 0.15 kg, per square foot of finished leather produced. The present analysis suggests, that the more energy intensive operations and the duration of each mechanical operation per skin or hide in processing contribute significantly to the total power consumption and corresponding CO2 emission values. A road map for reduction in CFP in leather processing has also been presented.