Zero waste bio-refineries: The example of Brazilian pulp and paper sector

The bio-based economy is a concept associated with the development of renewable resources management in a modern society, related to biomass, but also to the biogenic fraction of society’s generated wastes (Navia and Mohanty, 2012). About 170b t per year of biomass are produced by nature, of which only 3.5% (6b t) are utilised by mankind. Most of these 6b t are used for food, about one-third is for energy, paper, furniture and construction, and only 0.175% (300m t) are consumed for other non-food purposes, such as chemicals and clothing (Shen et al., 2009). Simultaneously, modern bio-refineries are understood as the synergistic processes that enable the whole use and valorisation of biomass. The concept behind sustainable and circular use of biomass, by implementing novel biomass bio-refinery processes, first focuses on high-value-added products and extraction of marketable chemicals, followed by biomaterials development and finally including the bio-energetic use of the residual biomass (Navia and Chamy, 2017). Contemporary consumerism does not appear to be an economic behaviour able to address the challenges related to increasing world population and large and fast-growing economies such as in China and India. In fact, as reported by Morone and Navia (2016), a major effect of these two trends will be a higher demand for food, manufactured goods and energy sources, adding pressure to the world economic system and the environment. Overarching these issues are the threat of climate change and the mounting concern to manage sustainably the increasing amounts of waste produced worldwide. A transition from the current ecologically untenable modes of consumption and production towards new and more sustainable models seems a desirable and much needed objective, passing from a linear take–produce–consume–discard material flow system to a circular and regenerative model. Therefore, zero waste bio-refineries could play a central role in paving the way for transition to a more sustainable economic system that uses resources in a more efficient and diverse way, diminishing the overall generation of wastes and facilitating the recovery of unavoidable discards as the source of resources for the production of new products.