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Sargassum spp is an invasive macroalgae and an alternative feedstock for bioethanol production. Sargassum spp biomass was subjected to high-pressure technology for biomass fractionation under different operating conditions of temperature and residence time to obtain glucan enriched pretreated solids (32.22 g/100 g of raw material). Enzyme hydrolysis process at high pretreated solid loading (13%, w/v) and enzyme loading of 10 FPU/g of glucan was performed, obtaining 43.01 g/L of glucose corresponding to a conversion yield of 92.12%. Finally, a pre-simultaneous saccharification and fermentation strategy (PSSF) was performed to produce bioethanol. This operational strategy produced 45.66 g/L of glucose in the pre-saccharification stage, and 18.14 g/L of bioethanol was produced with a glucose to bioethanol conversion yield of 76.23%. The development of this process highlights the feasibility of bioethanol production from macroalgal biomass in the biorefinery concept.

Undoped hydrogenated microcrystalline silicon was obtained by hot-wire chemical vapour deposition at different silane-to-hydrogen ratios and low temperature (<300 °C). As well as technological aspects of the deposition process, we report structural, optical and electrical characterizations of the samples that were used as the active layer for preliminary p-i-n solar cells. Raman spectroscopy indicates that changing the hydrogen dilution can vary the crystalline fraction. From electrical measurements an unwanted n-type character is deduced for this undoped material. This effect could be due to a contaminant, probably oxygen, which is also observed in capacitance-voltage measurements on Schottky structures. The negative effect of contaminants on the device was dramatic and a compensated p-i-n structure was also deposited to enhance the cell performance.

Geological and geophysical exploration campaigns have ascertained the coexistence of low to medium-temperature geothermal energy resources in the deepest regions of Italian sedimentary basins. As such, energy production based on the exploitation of available geothermal resources associated with disused deep oil and gas wells in Italian oilfields could represent a considerable source of renewable energy. This study used information available on Italian hydrocarbon wells and on-field temperatures to apply a simplified closed-loop coaxial Wellbore Heat Exchanger (WBHE) model to three different hydrocarbon wells located in different Italian oilfields (Villafortuna-Trecate, Val d’Agri field, Gela fields). From this study, the authors have highlighted the differences in the quantity of potentially extracted thermal energy from different analysed wells. Considering the maximum extracted working fluid temperature of 100 °C and imagining a cascading exploitation mode of the heat accumulated, for Villafortuna 1 WBHE was it possible to hypothesise a multi-variant and comprehensive use of the resource. This could be done using existing infrastructure, available technologies, and current knowledge.

In this study, microwave-assisted hydrothermal carbonization of waste coconut shell (feedstock) is reported. It is a thermo-conversion technique in which the feedstock was transformed into energy-rich carbonaceous material under mild conditions. The process was conducted in a microwave oven by heating the waste coconut shell in deionized water inside a pressurized vessel. The effects of different process conditions on the product yields, and the energy properties of the hydrochars were studied by varying the reaction temperature from 150 to 200 °C and residence time from 5 to 30 min. The results showed that there was transformation of the feedstock in the process due to the decarboxylation, dehydration, and demethanation reactions. This led to changes in the chemical and structural compositions, as well as increase in the energy properties of the prepared hydrochars. The higher heating value increased from 15.06 MJ/kg in the feedstock to 19.76 MJ/kg in the hydrochar. The energy properties of the hydrochars prepared in this study showed that microwave-assisted hydrothermal carbonization process could be a technique for converting waste coconut shell into high value-added product.

This study aims to evaluate the capability of SO2 to interact with soot and to determine the kinetics of this reaction under conditions of interest for combustion. The conditions of the soot reactivity experiments were: 1% SO2 with nitrogen to balance, around 10 mg of soot, and different reaction temperatures for each run: 1275, 1325, 1375, 1425, and 1475 K. Results demonstrate that SO2 does interact with soot. The evaluation of the soot reactivity has been based on the calculation of the time for the complete conversion of carbon through the employment of the Shrinking Core Model equations for decreasing size particle with chemical reaction control. The reactivity of soot with SO2 increased by a factor of about 3 when increasing the reaction temperature of the test from 1275 K to 1475 K. Kinetics in terms of Arrhenius parameters showed that the activation energy of the interaction of soot with SO2 was around 82 kJ/mol.

Nitrogen oxide (NO) and nitrous oxide (N2O) formation in the circulating fluidized bed (CFB) combustion can be controlled by air staging and fuel staging. An extensive test campaign was carried out with a pilot-scale CFB test rig to observe the possibilities of the methods in the spruce bark and bituminous coal combustion as well as in co-combustion. Fuel staging with liquid petroleum gas (LPG) was done alternately from three locations with three intensities. Air staging was studied alone and during the fuel staging experiment. The experimental trends for NO and N2O emission formation during fuel staging and air staging are presented in this study. It was observed that air staging and fuel staging can have opposing effects on nitrogen oxide emission formation, and thus, when used together, a clear understanding of the fuel behavior and conditions, as well as NO x chemistry in the combustor, is needed. Under the tested conditions, it was observed that if air staging is effective, then fuel staging does not bring further benefits in the NO reduction. Instead, the LPG feed can increase the emission in the lack of oxygen. However, if it is not possible to carry out air staging, then fuel staging can be used in generating oxygen-lean reducing zones for NO. The N2O concentration was also further reduced with LPG in the tests with effective air staging.

The growing interest in sustainable development is reflected in both the market’s sensitivity to environmental and social issues and companies’ interest in the opportunities that sustainable development objectives provide. SMEs, which account for most of the world’s pollution, have significant resource constraints for a sustainable development. Sharing their scarce resources can help them to overcome these constraints and to gain agility and organisational resilience against uncertainties, but the distrust inherent in belonging to different companies prevents them from sharing the necessary information for coordination purposes. This paper presents a coordination mechanism proposal with information asymmetry to allow independent companies’ resources to be sustainably shared as a technological driver. The proposed distributed coordination mechanism is compared to both a decentralised–uncoordinated and a centralised situation. The interest of the proposal is evaluated by a computer simulation experiment employing mathematical programming models with independent objectives in the Generic Materials and Operations Planning formulation with a rolling horizon procedure in different demand, uncertainty and product scenarios. Competitive improvement is identified for all members for their excess capacity use and their operations planning.