Utilization and re-use of solid and liquid waste generated from the natural indigo dye production process - A zero waste approach.

The main aim of this work is focused towards possible reuse of both solid and liquid waste generated from the natural indigo dye production process. The solid waste (C/N:15.01) was utilized to produce stable compost with possible re-use in Indigofera cultivation. Among seven compost combinations (C1-C7) using jeevamrutha (JA) and cow-dung (CD) as inoculum, C4 with 8% JA showed higher biomass degradation (51%) and plant growth potential (GI > 125%). Whereas the undiluted liquid waste was treated using algal consortia, bacteria, and indigenous microbial population, achieved a maximum removal of 90% ammonia, 82% nitrate, and 88% phosphorus for its re-use in the dye production process. Hence, incorporation of suitable waste management strategies in natural indigo dye production could help to achieve a zero waste sustainable process.