Harnessing of mussel shells in textile sandblasting

The nice worn look that provides sandblasting to denim clothes, hides a toxic abrasive process caused by poor working conditions. Rather than improving worker safety of workers, this process has been replaced by oxidising/chemical and thermal laser treatments, which are even more toxic and produce different textures. On the other hand, the world’s increasing production of delicious mussels results in a large quantity of shell waste ending up in landfills. The Sustainable Development Goals have raised awareness of the need for thoughtful waste management and the promotion of a circular life-cycle for goods. In order to find a solution for mussel shells, this work proposes to use the hard, fragile shells as an abrasive to replace the unhealthy silica sand in denim blasting. The physical properties of mussel shells have been assessed experimentally, and performance tests a have been conducted to characterise them. The performance of ground mussel shells in denim sandblasting of has been compared with that of industrial-grade garnet sand. Spectrophotometry measurements have observed similar fading performances for both garnet and mussel shells on denim under the same blasting conditions. Despite shell’s lower density, the smallest grit size (108 – 180 μ m ) achieved the best results. This reveals the importance of the number of impacts rather than the energy of each impact in denim sandblasting. This study confirms that mussel shells can replace silica in sandblasting processes, opening up new possibilities for using mussel shells as an abrasive material and reactivating sandblasting in the denim industry. • Inappropriate sand and protection pose serious health risks in denim sandblasting. • Chemical oxidisers used instead are more hazardous to workers and the environment. • Mussel shell waste is an underutilised by-product of the seafood industry. • This study looks at using ground mussel shells as abrasive for denim sandblasting. • Experiments show mussel shells are as effective as industrial garnet sand.