The “INNOVARE” Project: Innovative Plants for Distributed Poly-Generation by Residual Biomass

Abstract

The valorization of residual biomass plays today a decisive role in the concept of “circular economy”, according to which each waste material must be reused to its maximum extent. The collection and energy valorization at the local level of biomass from forest management practices and wildfire prevention cutting can be settled in protected areas to contribute to local decarbonization, by removing power generation from fossil fuels. Despite the evident advantages of bioenergy systems, several problems still hinder their diffusion, such as the need to assure their reliability by extending the operating range with materials of different origin. The Italian project “INNOVARE—Innovative plants for distributed poly-generation by residual biomass”, funded by the Italian Ministry of Economic Development (MISE), has the main scope of improving micro-cogeneration technologies fueled by biomass. A micro-combined heat and power (mCHP) unit was chosen as a case study to discuss pros and cons of biomass-powered cogeneration within a national park, especially due to its flexibility of use. The availability of local biomasses (woodchips, olive milling residuals) was established by studying the agro-industrial production and by identifying forest areas to be properly managed through an approach using a satellite location system based on the microwave technology. A detailed synergic numerical and experimental characterization of the selected cogeneration system was performed in order to identify its main inefficiencies. Improvements of its operation were optimized by acting on the engine control strategy and by also adding a post-treatment system on the engine exhaust gas line. Overall, the electrical output was increased by up to 6% using the correct spark timing, and pollutant emissions were reduced well below the limits allowed by legislation by working with a lean mixture and by adopting an oxidizing catalyst. Finally, the global efficiency of the system increased from 45.8% to 63.2%. The right blending of different biomasses led to an important improvement of the reliability of the entire plant despite using an agrifood residual, such as olive pomace. It was demonstrated that the use of this biomass is feasible if its maximum mass percentage in a wood matrix mixture does not exceed 25%. The project was concluded with a real operation demonstration within a national park in Southern Italy by replacing a diesel genset with the analyzed and improved biomass-powered plant and by proving a decisive improvement of air quality in the real environment during exercise.

Circular Economy Approach on Energy Cogeneration in Petroleum Refining

“…Three energy cogeneration studies were also identified as a circular economy strategy in the forestry sector. Costa et al [1] presented a case study in Italy on the valorization of waste biomass. The use of process residue as biomass cogeneration input promoted material circularity and added value to the residue, which is a circular economy strategy.…”

“…Power cogeneration is an alternative that has been employed by companies to promote the circular economy [1,2]. The use of materials for cogeneration improves energy efficiency, resource circularity and reduces environmental impact [3].…”

“…The use of materials for cogeneration improves energy efficiency, resource circularity and reduces environmental impact [3]. The valorization of waste biomass through cogeneration currently plays a significant role in the circular economy, in which waste must be reused to the maximum extent possible [1,2]. The sustainable use and recycling of secondary raw materials are the backbone of the circular economy, which aims to minimize environmental impact through the efficient conversion of resources and energy [4].…”

“…Anaerobic digestion for energy recovery from sewage sludge in Russian sanitation provided up to 7200 MWh/year of biogas, which reduced greenhouse gas emissions [23]. Energy valorization of waste biomass for cogeneration in the Italian agroforestry sector increased efficiency from 45.8-63.2%, due to the replacement of diesel generators with a biomass-powered plant, which reduced greenhouse gas emissions [1]. Furthermore, on the use of biomass in cogeneration, the evaluation in Portugal pointed to 97% cogeneration efficiency, 9% net electrical efficiency, and 88% thermal efficiency [24].…”

Available Pathways for Operationalizing Circular Economy into the Olive Oil Supply Chain: Mapping Evidence from a Scoping Literature Review

“…A wide range of conversion technologies are available for energy valorization of the olive oil sector by-products, with different possible outputs. The existing literature explores the opportunities of producing: syngas, to obtain electrical and thermal energy, by feeding a heat and power biomass plant with olive pomace [55][56][57], olive stones [59,60,62], or olive tree pruning residues [54,61]; electric energy [68] through the combustion of pruning residues; methanol from olive pomace via gasification [69], or from OMW via anaerobic digestion [58,70]; biogas by means of anaerobic digestion of olive pomace [67,74] or OMWW [71]; biofuel-as a sustainable alternative of biofuels based on specialized grown crops [21]-obtained from pruning residues combustion [64], from solid part of olive pomace gasification [73], or from waste cooking oil through homogenously catalyzed esterification [19]; combustible products from olive pomace (torrefied biomass or charcoal obtained, respectively, through torrefaction or slow pyrolysis processes) as sustainable substitutes of fossil fuels, such as coal [46,65].…”