Fluidized Bed Torrefaction of Agro-Industrial Residues: the Case Study of Residues from Campania Region, Italy

2014 - 2015The purpose of this Ph.D. project was to investigate the potential of the torrefaction treatment for upgrading low-value agro-industrial residues into useable solid fuels to be employed as high-quality energy carriers. The first phase of the project involved a screening of the agro-industrial residues available in Campania region (Italy) with good potentiality for energy applications. As a result of this analysis, tomato processing residues and olive mill residues, which have stood out as those in need of a more sustainable and environmental friendly disposal solution, were at first selected as biomass feedstocks for this Ph.D. project. However, practical difficulties encountered in the pre-treatment of the virgin olive husk (i.e., specifically in reducing the size of olives stone fragments which compose olive mill residues together with the olive pulp) led afterwards to discard such residue as a potential feedstock for the subsequent lab-scale torrefaction tests... [edited by author]XIV n.s

Genome-wide association studies in plants: the missing heritability is in the field

Genome-wide association studies (GWAS) have been even more successful in plants than in humans. Mapping approaches can be extended to dissect adaptive genetic variation from structured background variation in an ecological context

Nanomedicine for Imaging and Therapy of Pancreatic Adenocarcinoma

Pancreatic adenocarcinoma has the worst outcome among all cancer types, with a 5-year survival rate as low as 10%. The lethal nature of this cancer is a result of its silent onset, resistance to therapies, and rapid spreading. As a result, most patients remain asymptomatic and present at diagnosis with an already infiltrating and incurable disease. The tumor microenvironment, composed of a dense stroma and of disorganized blood vessels, coupled with the dysfunctional signal pathways in tumor cells, creates a set of physical and biological barriers that make this tumor extremely hard-to-treat with traditional chemotherapy. Nanomedicine has great potential in pancreatic adenocarcinoma, because of the ability of nano-formulated drugs to overcome biological barriers and to enhance drug accumulation at the target site. Moreover, monitoring of disease progression can be achieved by combining drug delivery with imaging probes, resulting in early detection of metastatic patterns. This review describes the latest development of theranostic formulations designed to concomitantly treat and image pancreatic cancer, with a specific focus on their interaction with physical and biological barriers

Musculoskeletal pain in schoolchildren across puberty: A 3-year follow-up study

BACKGROUND: Chronic Musculoskeletal Pain (MSP) in children can be due to non-inflammatory conditions, such as the benign joint hypermobility syndrome (BJHS) or idiopathic MSP (IMSP). Aim of the study was to evaluate type and persistence of MSP in a cohort of schoolchildren with MSP followed for 3 years, in order to identify the main risk factors. METHODS: Healthy schoolchildren, aged 8-13 years, underwent a general and rheumatologic examination, focusing on presence of chronic MSP, defined as continuous or recurrent pain lasting more than 3 months and heavily interfering with daily life activities, presence of generalized joint hypermobility, the body mass index and the pubertal stage. All symptomatic subjects were re-evaluated 3 years later with the same methods. RESULTS: Seventy of the 88 symptomatic subjects of the initial cohort of 289 were re-evaluated 3 years later. Of these, 38 (54.3 %) still presented MSP, including 19 with BJHS and 19 with IMSP. Main symptoms were lower limbs arthralgia and myalgia. MSP persisted more in females than in males (p = 0.038) and in pubertal rather than pre-pubertal subjects (p = 0.022); these subjects recovered significantly more both from BJHS (p = 0.004) and IMSP (p = 0.016). Gender did not influence the distribution of MSP according to pubertal stage. CONCLUSIONS: Female gender, BJHS and pubertal stage are important risk factors for persistence of MSP. Further studies are needed to evaluate the natural history of MSP towards adulthood and the role of the pubertal age

Methanation of syngas from biomass gasification: Small-scale plant design in Aspen Plus

The objective of this study is to investigate the upgrading of low-quality nitrogen-diluted syngas derived from biomass air gasification processes into a methane-rich gas stream. Both the thermodynamic and the kinetic aspects are addressed in the paper. Using the Aspen Plus software, a thermodynamic analysis was conducted; then, different plant designs are simulated and compared, including reactor sizing and performance. The results demonstrate that the upgrading of diluted syngas poses challenges which limit its application to small-scale decentralized systems. It was found that a system comprising of four adiabatic fixed-bed reactors, intercooling, and efficient water removal achieves a favorable balance between performance and cost. Operating the system at a pressure of 5 bar is deemed adequate as it reduces the required catalyst mass and prevents solid carbon deposition. Notably, this configuration achieved good results, including a 99.4 % CO conversion, 89.3 % CO2 conversion, and 95.6 % CH4 yield. The final methane molar content reached 26.4 %, with a calorific value of 8.62 MJ/Nm3 (STP)

Binary mixtures of biomass and inert components in fluidized beds: experimental and neural network exploration

Considering the little understanding of the hydrodynamics of multicomponent particle beds involving biomass, a detailed investigation has been performed, which combines well-known experimental and theoretical approaches, relying, respectively, on conventional pressure drop methods and artificial neural network (ANN) techniques. Specific research tasks related to this research work include: i. to experimentally investigate by means of visual observation the mixing and segregation behavior of selected binary mixtures when varying the biomass size and shape as well as the properties (size and density) of the granular solids in cold flow experiments; ii. to carry out a systematic experimental investigation on the effect of the biomass weight and volume fractions on the characteristic velocities (e.g., complete fluidization velocity and minimum slugging velocity) of the investigated binary mixtures in order to select the critical weight fraction of biomass in the mixtures beyond which the fluidization properties deteriorate (e.g., channeling, segregation, slugging); iii. to analyze the results obtained in about 80 cold flow experiments by means of ANN techniques to scrutinize the key factors that influence the behavior and the characteristic properties of binary mixtures. Experimental results suggest that the bed components’ density difference prevails over the size difference in determining the mixing/segregation behavior of binary fluidized bed, whereas the velocities of minimum and complete fluidization increase with a growing biomass weight fraction in the bed. The training of ANNs demonstrated good performances for both outputs (Umf and Ucf); in particular, the best predictions have been obtained for Umf with a MAPE1 <4% (R2=0.98), while for Ucf the best ANN returned a MAPE of about 7% (R2=0.93). The analysis on the importance of each individual input on ANN predictions confirmed the importance of particle density of the bed components. Unexpectedly, results showed that morphological features of biomass have a limited importance on Ucf

Sewage Sludge Gasification in a Fluidized Bed: Experimental Investigation and Modeling

Fluidized bed gasification is a promising process technology to manage the growing amount of sewage sludge (SS) requiring disposal. Two samples of SS, produced in different seasons of the year by a municipal wastewater treatment plant, were subjected to gasification at 850 °C in a bench-scale fluidized bed reactor using, as a gasification agent, a nitrogen/air mixture at different values of oxygen/fuel equivalence ratio (ER = 0.1–0.2). The starting materials and the output streams (syngas, tar, and solid residues) were thoroughly characterized. The fate of specific SS constituents and the characteristics of bottom ashes were addressed, so contributing to the problem of a proper SS management approach in the context of the circular economy. Computer-aided simulations were also performed, which allowed us to predict the composition of the syngas from SS gasification under operating conditions different from those experimentally investigated (i.e., reactor temperature and ER)