Chapter 1 - Anaerobic biovalorization of leather industry solid waste and production of high value-added biomolecules and biofuels

Abstract

The leather industry is one of the major polluting industries worldwide, as it generates a huge amount of liquid and solid wastes. The solid wastes include skin trimmings, keratin wastes, fleshing wastes, chrome shavings, and buffing dust. Currently, land filling is highly preferred for the disposal of these solid wastes and results in partial decomposition followed by the generation of toxic gases such as NH3, CH4, H2S, and CO2. The other conventional methods under practice are incineration/pyrolysis, liquefaction, and composting. In recent years, anaerobic biovalorization has become a promising technology for the conversion of these complex solid wastes into high value-added by-products that are considered to be nutrient-rich. Animal fleshing is mainly rich in proteins, fats, and carbohydrates. Therefore, the biovalorization of animal fleshing is highly exploited and has undergone many changes in technologic approaches to enhance the bioconversion and recovery of many more industrially important products. This chapter describes the effective utilization of animal fleshing for the production of various biomolecules such as enzymes, bio-carrier materials, and biofuels through anaerobic biovalorization. Furthermore, research and development must be targeted toward a few more bioactive compounds and secondary metabolite recovery from the animal fleshing.