No abstract

This study proposes a numerical model developed to characterize the chemical composition, heating value and temperature of the syngas produced by a downdraft gasifier fueled with residual biomasses. The process of gasification is essentially described through a global reaction that includes all the gaseous species and the yields of char and tar. The syngas chemical composition has been obtained solving a set of equations that are mass and energy balances, methanation and the water-gas shift reactions, which govern the gasification process. The proposed model was calibrated and validated through the comparison with two sets of experimental data. The comparison between the results of simulation and the experimental data has shown a very good agreement that allows pointing out the capability of the model to characterize the syngas composition and the temperature of the producer gas. Moreover, the performed sensitivity analysis shows the influence of moisture content and equivalent ratio on the chemical composition, equilibrium temperature and heating value of the producer gas.

Biomass is an alternative source to fossil fuels as proven by the increase of the primary energy production of 6.1% between 2012 and 2013. In European countries, the biomasses are 3.5% of renewable energy sources and they have a strategic role to reach the objective established by the European Directive 2009/28/CE. However, it is necessary to increase the use of renewable fuels, as syngas and biogas, to satisfy the objectives of the UE in the field of renewable energies and greenhouse gas emissions. The gasification and pyrolysis processes to produce syngas are promising technologies for a practical use of the biomass. In this context, gasification of biomass from agro-forestry activities is considered among the most effective sustainable technologies to recover waste that otherwise would be difficult to dispose. The micro-CHP electrical and thermal power were calculated through a balance of mass and energy based on an input-output model of the overall system. The results of this study demonstrated that it is possible to produce thermal and electrical energy for small agro-industries through the valorization of the residuals biomass deriving by their activities. (Presented at the AIGE Conference 2015)

Real time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of Next Step Tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms.A new set of real time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. Both diagnostics and algorithms were successfully used in several experiments, ranging from H-mode plasmas to configuration with ITBs.Since elaboration of computationally heavy measurements is often required, significant attention was devoted to non-algorithmic methods like Digital or Cellular Neural/Nonlinear Networks.The real time hardware and software adopted architectures are also described with particular attention to their relevance to ITER.

Ophiolitic rocks cropping on Calabria territory, southern Italy, can hold asbestiform minerals potentially harmful for human health. The aim of this work was to detect the fibrous phases of ophiolites along the Coastal Chain of northern Calabria and southern part of the Sila massif. Above 220 massive samples were collected in the study areas and analyzed using optical and electron microscopy, X-ray diffractometry, and Fourier transform infra-red spectrometry. The main fibrous constituent belonged to tremolite-actinolite series followed by fibrous antigorite that becomes more abundant in the samples collected in Reventino Mount surroundings. Results highlighted that serpentinites samples mainly consisted of antigorite and minor chrysotile. Samples collected along the coastal chain of northern Calabria did not hold fibrous materials. The results will be useful for Italian natural occurrences of asbestos (NOA) mapping in order to avoid an unintentional exposition by human activity or weathering processes.