| Abstract |
To date, clothing has been produced and disposed of in large quantities. It is also known that each process, from the procurement of raw materials to production, transportation, sales, laundry, and disposal, has a significant environmental impact. According to the Global Fashion Agenda, greenhouse gas (GHG) emissions from the fashion industry account for 4% of the global total. Therefore, apparel makers are shifting from a linear economy to a circular economy. For example, the Japanese start-up Curelabo Co., Ltd. (Okinawa, Japan) developed jeans (bagasse washi jeans) made from bagasse, which is a residual material derived from sugarcane after the extraction of cane juice. Furthermore, the use of improved dyeing reduces boiler fuel consumption and eliminates the need for detergents and acid. For disposal, the used jeans and their production waste are processed into biochar for carbon sequestration. In this study, we attempted to calculate GHG emissions using life cycle assessment (LCA) for the circular economy model developed by Curelabo Co., Ltd. GHG emissions from the production of bagasse washi jeans were 1.09 x 101 kg-CO2e. Dyeing, bleaching, and fabric finishing, known as the wet processes, were found to contribute a large proportion of GHG emissions due to their high energy consumption. Furthermore, the entire lifecycle of GHG emissions from bagasse washi jeans, including transport, sales, laundry, and disposal, were 1.53 x 101 kg-CO2e. First, the use of bagasse washi yarn for the weft reduced by 2.99 x 10-1 kg-CO2e compared with the use of conventional 100% bleached cotton yarn. Second, compared with conventional dyeing, GHG emissions from the improved dyeing process were reduced by 2.78 kg-CO2e. Third, the disposal of the used jeans and their production waste into biochar reduced GHG emissions by 9.01 x 10-1 kg-CO2e. Additionally, GHG emissions can be reduced by re-inputting waste in the paper-making process and by using liquefied natural gas as boiler fuel in the dyeing process. |