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Abstract The proposed innovative approach identifies a new application for biomass. Bioenergy is used to drive a desalination unit which produces water for irrigating energy crops. Biomass is cultivated on artificial soil made by a mixture of local soil and organic compost from MSW (Municipal Solid Wastes). This agro-energy farm scheme aims at rescuing arid lands near to the sea. The study defines a techno-economic compromise among energy crops, biomass generator, desalination unit and irrigation system, considering an arid area (10 ha) of Tenerife as reference case study. A small experimental activity (100 m 2 ) has also been performed on site. A Sweet Sorghum cultivation, a bioenergy generator, a reverse osmosis plant and drip irrigation system have been chosen. The main result of the study is that the possibility of retaining some 14–20% surplus (in terms of biomass or energy or water) exists. The system is energetically feasible: rescued land can be doubled in approximately 4 yr. This approach is applicable to many Mediterranean coastal areas, as well as other similar situations elsewhere.

AbstractBioenergy represents a unique opportunity for forestry companies to diversify the sources of income and create new stable business opportunities: a large number of initiatives has started in the last decades especially regarding decentralized power generation; nevertheless the conversion of the farmers to energy producers is not a trivial issue. The present work has focused on a possible alternative to biopower generation for forestry farms: the biomass carbonization (i.e. biomass slow pyrolysis). Charcoal making presents good prerequisite conditions for successful biomass based systems in the forestry sector: the system results incentive-independent, the power generation represents the co-product of a different primary production (resulting a real additional income), the plant capital cost is affordable for small scale farmers, operations requires technical skills normally available in the forestry sector and the reliability of the system is proven and credible, reducing the risks contained in business plans based on “number of hours of operation over several years”. Moreover charcoal is a well known product, familiar to forestry companies for a very long time, the market is well defined, the technology is known but still offers opportunities for further improvements (in terms of efficiency, costs and environmental impacts), the technology does not present major risk, the investment is well suited to small farmers and the process and technology gives a great opportunity for small scale and local supply chain development.Based on these considerations, the present work investigated the technological opportunities for small scale charcoal making systems. Various process configurations have been examined, focusing on advantages and disadvantages representative of each solution in view of small scale application suitable for the Italian case and a designed pilot plant has been proposed.

Biomass fast-pyrolysis oil (PO) is a liquid biofuel derived from lignocellulosic biomass: it offers several advantages compared to the direct us of solid bio fuels, such as high energy density, storability and transportability typical of liquid fuels, possibility to use the fuel in engines and turbines, easier downscaling of plants (which is a very important aspect for decentralized energy generation schemes). In addition, PO is the lowest cost biofuel, thus offering the possibility to penetrate also the large scale power generation market. Biomass POs have been studied and applications tested for many years, either for heat generation in medium-scale boilers or power generation. The present works reviews and analyses the most relevant experiences carried out so far and published results in power production from biomass PO. Power generation systems (PGS) which are here examined are gas turbines, diesel engines, stirling engines, as well as co-firing applications in large scale power plants (coal or natural gas plants). The main techniques for upgrading this biofuel and their impact on technologies are also shortly introduced and considered. The current status of development for each PO-based power generation option is discussed. This review work showed that long term demonstration (either technical or economical) is however still needed, even for the most developed technologies (use of PO in modified gas turbines and cofiring in natural gas stations): projects are on going to achieve long term demonstration.

The present work provides an analysis of the potential impact of fossil-based Low Carbon Aviation Fuels (LCAF) for the European aviation sector, with a time horizon to 2050. LCAF are a crude-derived alternative to kerosene, offering some Green House Gas (GHG) savings, and have been defined by ICAO as eligible fuels for mitigating the environmental impact of aviation. A methodological framework to evaluate the EU technical potential for LCAF production is developed, based on data on crude utilization for jet fuel production in EU refineries, relevant carbon intensity reduction technologies, market prices, and aviation fuel volumes. Two different baselines for fossil-derived kerosene carbon intensity (CI) are considered: a global figure of 89 gCO2e/MJ and an EU-27-specific one of 93.1 gCO2eq/MJ. Three scenarios considering increasing levels of CI reduction are then defined, taking into account the current and potential commercial availability of some of the most relevant carbon intensity reduction technologies. The analysis demonstrates that, even if LCAF could offer GHG saving opportunities, their possible impact, especially when compared to the ambition level set in the most recent European legislative proposals, is very limited in most of the analysed scenarios, with the exception of the most ambitious ones. At 2030, a non-zero technical potential is projected only in the higher CI reduction scenario, ranging between 1.8% and 14.2% of LCAF market share in the EU-27 (equal to 0.6 to 4.75 Mtoe), depending on the considered Baseline for CI. At 2050, almost all considered scenarios project a larger technical potential, ranging between 6.9% and 22.2% for the global Baseline (2.21 to 7.13 Mtoe), and between 1.8% and 16.2% for the EU-27 Baseline (0.58 to 5.2 Mtoe). LCAF additional costs to current production costs are also discussed, given their relevance in large-scale deployment of these technologies, and are projected to range between 39 and 46.8 USD/toe.

Abstract Aviation is steadily growing worldwide as well as in the European Union (EU). Overall, EU transports increased their GreenHouse Gas (GHG) Emissions since 1990, while the other energy sectors succeeded in achieving a constant reduction over the same period. In this context, air transport is the most critical area to decarbonize, given the limited number of options that can be implemented, such as optimization of flight routes, increase of jet engine energy efficiency, and few others. Switching to renewable or low carbon fuels is thus the main opportunity for aviation. Large scale deployment of Sustainable Aviation Fuels (SAF) is however a real challenge, as it requires large investments in new production facilities, strong reduction in production costs (over the entire value chain, i.e. including feedstock production, collection and delivery), and considerable investments in ASTM certification. The present work shortly reviews the perspectives of aviation fuel in terms of demand and GHG emission trends, possible routes to jet fuel production, and the status of ASTM certified routes to jet fuel as of today.

Advances in sustainable biofuel production and use. The XIX international symposium on alcohol fuels

Abstract Used Cooking Oil (UCO) and pure Fatty Acids (FAs) derived from food processing represent sustainable feedstocks for biofuel production. The catalytic and non-catalytic pyrolysis of these residual oils is a possible pathway to advanced biofuel production, alternative to catalytic hydrotreatment, already commercially deployed in large-scale installations. The present work first carried out a literature review of previous research works in the field, which provided the key information to the following implementation of a pilot-scale dedicated experimental work aimed at producing bio-hydrocarbons from residual vegetable oils, with a special focus on paraffinic fuels. Based on the literature survey, 4 different catalysts were selected for the experimental investigation. Catalytic and non-catalytic pyrolysis of UCO was initially carried out in 1.5 kg h −1 (max) feed pilot unit, operated at 500 °C, with the catalytic reactor working at 4 and 2.5 h −1 Weight Hourly Space Velocity (WHSV). Liquid yields and corresponding hydrocarbon fractions were investigated: these initial results suggested to extend the study to catalytic pyrolysis of pure FAs. At T = 500 °C and with activated carbons as catalyst, the total observed hydrocarbon yield mass fraction on UCO and FA increased from 23% (UWHSV = 4 h −1 ) to 35% (UCO, WHSV = 2.5 h −1 ) and finally to 40% (FA, WHSV = 2.5 h −1 ). A slight reduction in the overall liquid yield mass fraction was also observed in this last experiment with FAs (from 63% to ≈49%). Even if the current work on the pilot pyrolyser did not aim at investigating energy and process optimization, including yield maximization and catalyst lifetime, experimental results indicated that catalytic pyrolysis could be a promising way for industrial production of hydrocarbons from low quality lipid-based materials (as it is the case of UCOs) and without requiring hydrogen for catalytic hydrotreatment.

Abstract The CarbOn pilot plant is a continuous biomass carbonization system, rated for a capacity of up to 50 kg h−1 and based on open top, downdraft technology, operating in oxidative pyrolysis in the temperature range of 500–650 °C and equivalence ratio (ER) between 0.1 and 0.2. In the reported validation tests, carried out on small size chestnut woodchips, charcoal mass yield in excess of 22.4 ± 0.7 wt% (dry base) has been achieved, with a fixed carbon content higher than 85 wt% (dry base). The fixed carbon yield (FCy) was 18.2 ± 2.2 wt% (dry base), the char carbon yield (CCy) 38.3 ± 1.6 wt% (dry base) and the net energy conversion efficiency to char (e) equal to 41.2 ± 2.2% (wet base). Volume concentration of permanent gases in the pyrolysis vapors and condensable species were also measured before incineration and critically compared against literature data. The organic condensate from oxidative pyrolysis was obtained as 4.9 wt% of the dry biomass, and around 58 wt% of its constituents have been identified; in order of decreasing abundance, the organic fraction of condensate was composed of organic acids, aromatics, furans, anhydrous sugars, phenols, methanol, PAHs, acetaldehyde, ketones. Measured and calculated performance data shows that the pilot unit can produce high quality charcoal, meeting and exceeding the product specifications set by standard EN 1860-2 for BBQ lump charcoal as well as those set forth by international voluntary standards on biochar quality for soil application.

Power production from biomass derived pyrolysis liquids has been under development for the past few years. If technically successful, it would make decentralized bio-energy production possible. Several technologies and system components have been developed by academia, R&D organizations, and industrial companies in many countries. Much experience has been gained and many useful results published. The present work aims at reviewing the most significant experience in power generation from biomass liquids produced by fast pyrolysis processes. Power plant technologies addressed are diesel engines, gas turbines, and natural gas/steam power plants. Main results are reviewed and R&D needs identified for each technology. The analysis shows that even for the most promising solutions long-term demonstration has not yet been achieved. Pyrolysis liquid use in gas turbine plants and in co-firing mode in large power stations are technically most advanced. Recent work with diesel engines also appears quite promising.