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A reliable assessment of the availability of bioresources represents the first step to defining local value chains of particular interest. More than 190 and 50 Mt/y of bioresources are currently available in Europe and Italy, respectively, even if they are not fully valorized. The best end use of these feedstocks is strictly dependent on specific territorial/regional peculiarities, that consequently affect the products' final properties. In this work, the Italian web-GIS-based tool “Atlante delle biomasse” was used to determine the availability of many bioresources in Italy at the regional level. A lump classification criterion was used to categorize the available biomasses, and, then, an optimization algorithm based on a process superstructure was applied to find out the available fraction of bioresources, the amount of biofuels potentially obtainable and, consequently, the regional fuel demand coverable by biofuels. In particular, only the energy-self-sufficient technologies with higher TRLs were considered in the mathematical model. The integration between the different selected bioresources led to three biofuels to be considered, evaluating the percentage of biofuel demand that could be covered for each Italian region. The final potential production of biofuels derived from local bioresources in Italy settles down on the range 9 107 – 1.6 108 GJ/y covering about 5, 50, and 100 % of methane, biodiesel and bio-LPG demand respectively. Bio-LPG demand for all regions was to be considered completely satisfied, biodiesel production was also sufficient to cover high demands, on the other hand, low values of biomethane requirements coverable were obtained. [ABSTRACT FROM AUTHOR]

The agro-food industry generates important quantities of by-products, often considered waste, which represent for the companies huge costs of handling and disposal. On the other hand, they contain copious amounts and varieties of compounds that, appropriately extracted, purified, and processed, can be valued in several industrial sectors. Their exploitation generates an improvement of the sustainability performance of the supply chains, since it generates economic advantages, making available new commercial products and reducing disposal costs, improves the environmental performance of the agro-industrial productions, and allows new employment opportunities, thanks to the development of new industrial sectors. The Percival project aims to valorize the byproducts of agro-industrial supply chains of South of Italy, converting them into high-added value products, through innovative, efficient, and low environmental impact processes, going for the development of technologies that could represent new business opportunities for this territory. Particularly, the project deals with the development of processes for pretreatment, extraction, separation, and chemical/biotechnological transformation, using a biorefinery cascade approach. Indeed, the study of processes having the purpose of converting the residues from the above-mentioned transformations into advanced biofuels (biomethane) and agricultural products (e.g. soil improver and bio-stimulants) are also included in the project’s scope. The present paper provides an overview of the Percival project, along with the evaluation of the availability of residual biomasses from the supply chains of typical Southern agricultural products, and the valuable bioproducts achievable from these feedstocks, through a biorefinery processing scheme. [ABSTRACT FROM AUTHOR]

Green diesel is a real solution for the decarbonization process of the world, reducing in this way, carbon dioxide emissions to the atmosphere. The present work proposes a flexible biorefinery design where green diesel is produced by catalytic hydrotreatment of four vegetable oils: soybean, sunflower, palm, and cardoon oil feedstock. The process was simulated in Aspen Plus®. A multi-bed reactor composed of four catalytic beds with quenching cooling is designed and simulated in the presence of Ni-W/SiO2-Al2O3 catalyst, in addition to a separation phase train to obtain the green diesel. Sensitivity analyses were carried out to determine the parameter conditions of the unit operations. The results of the model reflex a molar conversion of triglycerides above 97% and overall mass yield into diesel fraction above 79%. Total capital costs and operating costs of the process were determined in the economic analysis, where a base case is considered for the calculations, obtaining the maximum vegetable oil market price can be sustainable to make economically convenient the biorefinery. Soybean oil resulted in the worst feedstock due to the high percentage of unsaturated bonds, while cardoon oil can be considered the best source to produce green diesel thanks to higher conversion yields. [ABSTRACT FROM AUTHOR]

In recent years there was an increase in the use of renewable energy resources but there are still technological limits regarding the not constant power productivity. To face this problem, a possibility is to convert the surplus of renewable electricity into chemical energy producing hydrogen through electrolysis. The main drawback of this solution is that hydrogen is still hardly usable and so a good choice could be to convert this fuel into a more common one, such as methane. This work aims to carry out a techno-economic analysis of an upgrade section for a biogas plant to convert CO2 into biomethane. The used methodology consists in sizing the methanation reactor considering kinetic and catalyst effectiveness, membrane separation and simulating the whole process changing operating conditions such as temperature and pressure. The results of this study show that methanation can be extremely efficient in terms of energy consumption and carbon conversion. The methane production cost without accounting for hydrogen cost is between 0.15-0.19 €/kg, the same cost range as commercial natural gas. This value mainly depends on the capital and operating cost of the compression system. However, by including the high cost of hydrogen obtained by electrolysis, equal to 5 €/kg, this process is not economically feasible. On the other hand, by exploiting the surplus of renewable energy production, the cost of green hydrogen is expected to radically decrease shortly. [ABSTRACT FROM AUTHOR]

The lignocellulosic biomass valorisation is a central challenge of the bioeconomy transition, which passes through optimization of the entire value chain, from feedstock availability, sustainable conversion processes, to final target products. In this framework, the oleaginous yeasts represent a versatile tool to produce biobased chemicals and intermediates. They are flexible microbial factories able to grow on different side-stream carbon sources such as those deriving from lignocellulosic biomass, and this characteristic makes them excellent candidates for integrated biorefinery processes through the production of microbial lipids/oils. This work aims at a techno-economic analysis of a lignocellulosic biorefinery producing microbial oils by oleaginous yeasts (Lipomyces tetrasporus). The wheat straw residues were considered as the lignocellulosic feedstock thanks to a huge amount in the European territory. Experimental data obtained by a complete lab-scale 2G-sugars platform (steam explosion pretreatment, enzymatic hydrolysis, fermentation) were used for the analysis until microbic growth. Commercial/literature data were considered for the lipids extraction and purification stages. An assessment of the mass and energy balances, equipment sizing, costs estimation was carried out with the main results showing a production cost of the microbial oil about 4 €/kg with the enzymes supply as the major cost contribution. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass can be converted to biofuels and biochemicals through several process pathways: pretreatment and sugars fermentation, thermochemical conversion (pyrolysis, gasification) and syngas synthesis. A promising syngas valorization process consists of the syngas fermentation, able to maximize the biomass fraction used for the fermentation. The limits of this process are the need for high-quality syngas, fermentation rate optimization and the two-phase bioreactor design. This work aims to analyze the two effects (fermentation and gas to liquid mass transfer) distinctly. A syngas fermentation kinetics was modeled in order to optimize the fermentation conditions in terms of substrate and microorganism concentrations maximizing the acetic acid yield. Under the hypothesis of constant CO and H2 concentration, the gas-liquid mass transfer coefficients were estimated considering a syngas composition coming from the Cynara cardunculus L. residual biomass gasification. Results presented identify the optimal CO and H2 concentrations 0.01 and 0.1 mmol/L respectively, with an initial microorganism concentration equal to 2 g/L, obtaining a maximum acetic acid yield and an acetic acid maximum concentration of 12.5 % and 4.2 g/L respectively. [ABSTRACT FROM AUTHOR]

The valorization of municipal waste represents one of the major opportunities for the next future. In particular, the Organic Fraction of Municipal Solid Waste (OFMSW) can be used in anaerobic digesters to produce biogas/biomethane. Furthermore, a fraction of Municipal Solid Waste (e.g. non-recyclable plastics, paper cardboard, etc.) can be converted to Refuse Derived Fuel (RDF). Both biogas/biomethane and RDF may be further converted in syngas (a mixture of H2, CO and CO2) by using several technologies, such as steam reforming for the former, and gasification for the latter. Syngas may be used as fuel in CHP plants or for the production of chemical intermediates and fuel. The digestate derived from anaerobic digestion, as well as CO2 from biogas, can be used as nutrients source to grow microalgae, which are feedstock suitable for supercritical water gasification (SWG). In this paper, an integrated process is proposed, by coupling an anaerobic digestion plant for biomethane production with (i) high-temperature gasification of RDF and (ii) SWG of algae grown up with digestate and CO2 from biogas. The biomethane is assumed to be converted in syngas by steam reforming. Considering its importance for the chemical industry chain, methanol is considered as a target product. Methanol synthesis is assessed in terms of mass and energy balances and direct CO2 emissions. The results show that high-temperature endothermic processes require the use of purge gas as a fuel in a burner to sustain itself. The lowest direct CO2 emission value per kg of methanol produced is obtained in the case of high use of RDF, minimum recycling of CO2 to algae production and minimum purge ratio. [ABSTRACT FROM AUTHOR]

New technologies for air quality measurement, including real-time on-road air quality monitoring systems (ROMs), have improved the spatial resolution of data. However, measured data can miss due to restricted traffic zones. Different algorithms can estimate the missing data in these points, using available measured data in the neighbourhood. In this study, the results of the applications of an interpolation method taking into account the effect of wind direction and intensity by means of a simple dispersion model is presented. Thanks to the large amount of data provided by the innovative dynamic monitoring system (ROM), the proposed model is able to return, with a good approximation, reliable PM10 and PM2.5 concentration values, with a resolution of 1 km². [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass, including both herbaceous and woody feedstock, is currently widely used in many biorefineries. The lignin fraction (20-35 %DRY) is typically thermochemically converted into the cogeneration section of the biorefinery to produce heat and electricity. However, lignin holds a greater potential in several industrial sectors to produce biobased materials and several chemical building blocks. In particular, novel technologies allow obtaining low molecular weight compounds, such as aromatic or hydrocarbons. In this work, a mathematical methodology was developed to evaluate the best option in terms of lignin valorization. A process superstructure was built to compare alternative process pathways from lignocellulosic biomass. The following conversion options were considered: jet-fuels (JF), phenol-formaldehyde resins (PFR), polyurethane foams (PUF), and syngas for green electricity generation. By AIMMS optimization software, a Mixed Integer Linear Programming (MILP) was applied to obtain a simplified mathematical analysis and, consequently, the maximum lignin cost maximization for each lignin valorization process. In particular, process conversion, required utilities, product values were assessed for each process technology. Preliminary results show that the production of phenol-formaldehyde resins is the process closer to the market uptake. On the other side, polyurethane and jet-fuels appear still far from the market and their production would be feasible at a polyurethane foams and jet-fuel selling price at 300 % of the current selling price. [ABSTRACT FROM AUTHOR]

In this paper an on-road network of monitoring stations for the air quality is organized in order to provide data with high spatial resolution in a wide urban area. On this purpose a dedicated experimental set-up was developed in order to be installed on board of DHL courier vans. The monitoring station is completely automated and transmit continuously environmental data and positions during the daily route of the van. In order to aggregate data, the city map is partitioned into a grid of 1 km². The system is tested by comparing average concentrations with those of a fixed monitoring station. [ABSTRACT FROM AUTHOR]