Valorisation of residual biomass generated by the primary sector for a circular bioeconomy

Circular economy aims to create a system that allows optimal reuse of products and materials. The term defines an economy designed to regenerate itself. In a circular economy, there are two material flows: the biological ones, able to be reintegrated into the biosphere, and the technical ones, destined to be enhanced without entering the biosphere. The circular economy is therefore a system in which all activities, starting with extraction and production, are organised so that someone's waste becomes a resource for someone else, i.e. an economic system planned to reuse materials in subsequent production cycles, minimising waste. In the linear economy, on the other hand, once consumption is over, the product cycle ends and it becomes waste, forcing the economic chain to continuously repeat the same pattern: extraction, production, consumption, disposal. In this context, the contribution provided by the valorisation of residual biomass and municipal waste is fundamental for the production of renewable biological resources and their conversion into new value-added products. This is the background to the thesis work which has been divided into three main parts. After an in-depth study on the circular economy concept, the differences and points of contact with the bioeconomy concept and above all the opportunities linked to it, in collaboration with University of Basilicata (Scientific part of the project) a general review was carried out. This review has considered the residual biomasses coming from the various agricultural activities (mowings and pruning by-products), from zootechnical activities (sludge deriving from animal manure, etc.), from agro-food activities (deriving from olive, wine, dairy, cereal processing, etc.) and from forestry activities (from forest cutting and use, forest cleaning, etc.) that are practised in the Basilicata region. Subsequently, a focus and a cognitive survey on the by-products generated by the wine sector in the Basilicata region, on their reuse state of the art and on their possible valorisation forms with particular attention to restoring soil fertility with a view to the circular economy, was carried out. The industrial part of the project, instead, was carried out with the collaboration of Innova - Consorzio per l'Informatica e la Telematica srl. After a general review of the waste legislation in the Basilicata region –especially the differences between waste and by-products - the problems related to the state of the art concerning their production, management and disposal, the phD thesis work has focused on the feasibility study (economic and environmental) of new models for the management, treatment and valorisation of organic waste flows (from separate collection) and agricultural by-products (especially those coming from wine supply chain) from the perspective of the circular economy as an alternative to the current models based on the linear economy. These new governance models called "proximity composting" and “home composting”, alternative and more sustainable than the current one, on the other hand aim at a more sustainable management of these flows based on their “zero-kilometers treatment”. On the other hand, they aim to empower the communities that become an active part of the process: citizens are directly involved and partially autonomous in the management of their municipality waste. Specifically, starting from a basic organisational idea, an in-depth study on its real feasibility was carried out, based on an integrated planning of the different aspects involved in the elaboration of the models themselves. Subsequently, the discussion focused on IoT (Internet of Things) technologies applied to the proposed models with a dual purpose:  remote control and monitoring in Near Real Time of each phase of the process: the flows collection, the transport, the final destination and the variation of the various parameters during the proposed composting process;  possibility of implementing the "punctual tax" in accordance with the Ministerial Decree on the Environment of April 20, 2017. The proposed models, alternatives to the current one - composting in very distant industrial plants - which is unsustainable, very expensive and disadvantageous, aim first of all to improve separate collection in each municipality, and consequently to reduce the amount of organic waste to be treated, but also to give wine by-products a more sustainable second life, in the context of the circular economy. Finally, in cooperation with the international partner of the project, the Energy Agency of Plovdiv (EAP), after studying the state of the art regarding the production, management and treatment of municipal waste in the city of Plovdiv, the related problems and possible future challenges, the home composting model, hypothesised for the Basilicata Region, has been adapted to this city. As in the case of the Basilicata region, the model has been planned and studied from an economic and environmental point of view, and its feasibility has confirmed that it could be a good alternative to the current one, which does not provide for separate collection, but directly for the disposal of urban waste in landfills.