A climo and litho soil-sequence on the Vico volcano (Italy)

A la suite d'une cartographie pédologique détaillée de la majeure partie de l'appareil volcanique de Vico (Italie), une séquence topoclimatique a été définie. Cing profils ont été choisis à des altitudes représentatives des principales zones climatiques. Les changements observés dans les sols correspondent bien aux effets de variations significatives des paramètres climatique

Anaerobic Digestion of Macrophytes Algae for Eutrophication Mitigation and Biogas Production

Abstract An economy based on biofuels requires production methods which are economically and technically competitive. The production of biogas from biomass by microorganisms is an attractive and ambitious possibility. Marine and lake algae represents a biomass source that could be used for biogas production and their extraction is of benefit for the aquatic environment reducing eutrophication. The goal of the experimental work is to evaluate the algae biomass naturally present in lagoon environment and analyze the biogas resulting from the anaerobic digestion. The Biomethane Potential (BMP) of macrophytes with inoculums from a sewage sludge treatment plant was measured at the University of Perugia. The CH 4 content of biogas was approximately 52%, cumulative CH 4 yield of 217 Nm 3 /t SV was observed after 41 days of digestion

A Quantitative Methodology to Measure Injector Fouling Through Image Analysis

Abstract The use of vegetables oils in a compression ignited internal combustion engine presents some critical issues as the large amount of carbon deposits on the tip of injectors, which significantly influence emissions and engine performance. A previous draft methodology was developed by the authors, based on images capture and post-processing. The carbon deposit was correlated with the number of pixels in the gray scale, so it was possible to determine a Fouling Index. First results showed interesting perspectives and some limits: the aim of the present work is the optimization of the test bench and methodology. At first an improvement of image acquisition, increasing sampling frequency and image resolution, is performed, replacing the old camera with a digital microscope and improving both injector and microscope positioning. The test bench prototype has been realized with the aid of 3D printing, obtaining fundamental mechanical components. Also an alternative methodology is proposed to evaluate carbon deposits volume through a Volumetric Index. The new methodology validation was done using images sampled with the previous test bench. The performances of the Fouling index and of the new Volumetric Index were compared and fouling was examined in the real case of a diesel engine, fed with diesel and sunflower oil. Results show a greater reliability of the new Volumetric Index

Studio di settori del litorale Emiliano-Romagnolo soggetti ad interventi di ripascimento

In questa tesi è stato condotto uno studio sull’evoluzione dei settori di Misano Adriatico e Riccione Sud in seguito agli interventi di ripascimento, attuati sul litorale emiliano-romagnolo da ormai 25 anni: si tratta di un’area dal delicato equilibrio, per questo da sempre oggetto di monitoraggio. Utilizzando rilievi batimetrici (di prima pianta, seconda pianta e primo monitoraggio), profili di spiaggia e dati relativi alle granulometrie sono state osservate le principali variazioni della linea di riva e di fondale caratteristici di questo tratto costiero nel periodo relativo all’intervento di ripascimento del 2016. I cambiamenti ed i trend evolutivi individuati si sono confermati il risultato dell’azione congiunta di fattori naturali e antropici, i quali hanno fortemente influenzato la situazione critica di questi settori di spiaggia

Pyrolysis of Olive Stone for Energy Purposes

Abstract Pyrolysis of biomass is a promising technology for the production of distributed and renewable energy on small and micro-scale since it produces a gas with relatively high calorific value, which can be burned in an internal combustion engine or in a microturbine; pyrolysis also generates by products (char and tar) which can be used to provide energy to the process or for cogeneration purposes. This research is aimed at the exploitation of waste from agricultural production processes, in particular olive mill wastes whose management has critical environmental and disposal costs; the yields of pyrogas, tar and char obtained from the pyrolysis of olive stone in a batch reactor was measured. Pyrogas produced is sampled through a line for the sampling of condensable substances in accordance with existing regulations, CEN/TS 15439, and once purified from water vapor and tars is analyzed with micro-GC. The data collected is used to perform mass and energy balances and to determine the content of tars and the Low Heating Value (LHV) of the gas produced

Early-Stage Detection of Solid Oxide Cells Anode Degradation by Operando Impedance Analysis

Solid oxide cells represent one of the most efficient and promising electrochemical tech- nologies for hydrogen energy conversion. Understanding and monitoring degradation is essential for their full development and wide diffusion. Techniques based on electrochemical impedance spectroscopy and distribution of relaxation times of physicochemical processes occurring in solid oxide cells have attracted interest for the operando diagnosis of degradation. This research paper aims to validate the methodology developed by the authors in a previous paper, showing how such a diagnostic tool may be practically implemented. The validation methodology is based on applying an a priori known stress agent to a solid oxide cell operated in laboratory conditions and on the discrete measurement and deconvolution of electrochemical impedance spectra. Finally, experi- mental evidence obtained from a fully operando approach was counterchecked through ex-post material characterization

Operando Analysis of Losses in Commercial-Sized Solid Oxide Cells: Methodology Development and Validation

The development of decarbonised systems is being fostered by the increasing demand for technological solutions for the energy transition. Solid Oxide Cells are high-efficiency energy conversion systems that are foreseen for commercial development. They exhibit potential power generation and power-to-gas applications, including a reversible operation mode. Long-lasting high performance is essential for guaranteeing the success of the technology; therefore, it is fundamental to provide diagnosis tools at this early stage of development. In this context, operando analysis techniques help detect and identify incipient degradation phenomena to either counteract damage at its origin or correct operando protocols. Frequent switches from the fuel cell to the electrolyser mode add more challenges with respect to durable performance, and deep knowledge of reverse- operation-induced damage is lacking in the scientific and technical literature. Following on from preliminary experience with button cells, in this paper, the authors aim to transfer the methodology to commercial-sized Solid Oxide Cells. On the basis of the experimental evidence collected on planar square cells under dry and wet reactant feed gases, the main contributions to impedance are identified as being charge transfer (f = 103–104 Hz), oxygen surface exchanged and diffusion in bulk LSCF (f = 102–103 Hz), and gas diffusion in the fuel electrode (two peaks, f = 1–100 Hz). The results are validated using the ECM methodology, implementing an LRel(RctQ)GWFLW circuit

Anaerobic Digestion of Spoiled Milk in Batch Reactors: Technical and Economic Feasibility☆

Abstract The economic feasibility of the energy conversion through anaerobic digestion of spoiled milk was assessed for the microscale biogas production and heating value was determined experimentally on a pilot plant with a mixture of spoiled milk and an inoculum previously optimized with Anaerobic Biomethanation Potential tests. Results shows that the feasibility of a 100 kWel plant is characterized by a quite short return time of the investment. Considering a discount rate of 5% and a timespan of investment equal to 20 years, payback period is equal to 8-9 years, Net Present Value is equal to 806,903 € and Internal Rate of Return is equal to 16%