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Urolithiasis is a multifactorial disease; in recent years, its incidence has gradually increased in pediatric age. Among the factors involved in urolithiasis pathophysiology, urinary tract anomalies and metabolic diseases are the most relevant, although ethnicity and environmental factors may have an important role. The advances in technology and miniaturization of endoscopic devices have permitted the use of Retrograde Intrarenal Surgery (RIRS) to treat kidney and ureteral stones. Nowadays, flexible ureterorenoscopy and laser lithotripsy, which are techniques that have been applied in the management of adult upper urinary tract disorders, are also used in children as a minimally invasive treatment of urolithiasis with encouraging, effective and safe results. The Authors report a retrospective review of their record of cases considering 21 pediatric urolithiasis treatment procedures performed between October 2017 and April 2019 in a total of 17 patients (10 males and 7 females). Six procedures involved the use of the flexible ureterorenoscope (FURS) while in 15 procedures the application of the laser fiber was used (FURSL). A case of laser lithotripsy for bladder stone was included. The average age of patients was 10.5 years (2-18 years). The renal pelvis dilatation pretreatment was evaluated in post-operative follow-up. From the evaluation of the sample in analysis, the use of RIRS has good results in the treatment of paediatric urolithiasis, emerging as a valid option in the management of the paediatric population in terms of efficacy and safety, with an improvement in patient outcomes.

The reported work deals with the use of lignin rich solid, which is available as residue from enzymatic hydrolysis of lignocellulosic biomass, to produce syngas. The tested process was an updraft gasification carried out at pilot scale of about 20 kg/h as dry feed. The thermal conversion of the residue was investigated by TGA in air, carbon dioxide and nitrogen atmospheres pointing out the relative contribute of pyrolysis, combustion and gasification at different temperatures. In the plant tests, the residue was completely converted in gaseous and liquid energy carriers with overall energy efficiency near 90%. Several process conditions were examined corresponding to different flows of O2 and steam. The molar ratio H2/CO in syngas increased by using steam as co-gasification agent. Steam was necessary to stabilize the process in the case of using oxygen as main gasification agent. Oxy-steam gasification provided the best results in terms of syngas heating value and highest thermal power output of the plant., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 1241-1244

The aim of this work is to predict the reactivity and conversion profiles of the steam-char gasification step of residual biomasses that are typical of the Mediterranean area. In order to simulate the conversion profiles of chars in steam atmosphere, kinetic constants and reaction models were correlated with the main catalytic and inhibiting elements. The chars were obtained from ctrus peel, grape pomace, reed (Arundo Donax), and residues from 2nd generation bioethanol production. The study was carried out by means of isothermal thermogravimetric experiments of the selected biomass chars in the temperature range from 650°C to 825°C in 50% (v/v) steam atmosphere (N2 as balance gas). By indicating as Inorganic Catalytic Ratio, ICR = (Ca+K)/Si the ratio between the main inorganic elements with catalytic and inhibiting effects, it was found that samples with ICR > 1 showed a so called sigmoidal conversion, which can be described by classical Avrami type models. The chars with ICR < 1, showed a decelerating profile of conversion, described by n-order models. The computed char conversions were in good agreement to the experimental data., Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 760-763

I sistemi di cogenerazione alimentati da fonti rinnovabili, quali le biomasse, risultano di grande interesse per la produzione efficiente di energia in ambito industriale. Pertanto, scopo del presente lavoro è lo studio dell'integrazione, in tale contesto, di un sistema di cogenerazione alimentato da syngas prodotto tramite gassificazione di biomasse. Tale valutazione è stata sviluppata mediante la realizzazione di modelli matematici di simulazione per la modellazione di un impianto in assetto cogenerativo.

The growing need to reduce the environmental impact of the modern lifestyle imposes a continuous development of novel technologies aimed at a severe reduction of pollutant emissions in order to ensure a tolerable quality of life in metropolitan areas. Among potential alternatives, particular attention has been recently addressed toward the exploitation of residual biomass and wastes as sources for syngas production by thermo-chemical processes for heat and power production. Fruits processing industries generate important amount of residues, which must be managed properly by recycling, incineration or land filling. Due to the high carbon content, these residues represent a significant source of energy that could be valorized by gasification processes. Hence, our attention was focused on the energy recovery from orange peels residues produced by a Sicilian agro-industrial company by steam gasification. Thermodynamic and experimental analysis were carried out. Experiments were performed in a fixed bed laboratory scale reactor working with catalytic materials (Ni/Al2O3, MgO and dolomite mineral) with the biomass in order to investigate the influence of experimental conditions on the outlet stream compositions, mainly in terms of hydrogen content of the produced syngas. Results were compared to thermodynamic data in order to gain information of the experimental method used. The results have confirmed successfully the experimental results compared with the simulation data. The highest concentration (65.9%) of hydrogen volume in the syngas mixture was reached with dolomite mineral as catalyst., Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 918-921

Bioethanol produced from lignocellulosic biomass is a promising alternative for fossil fuel substitution. Hydrolytic lignin rich residues could be exploited through gasification for more efficient bioethanol production processes. The char gasification is generally one of the slowest thermal steps and a fundamental understanding of the heterogeneous reaction kinetics is needed forreactors design. The aim of this work was to investigate the kinetic behavior of chars from byproducts of 2nd generation bioethanol production. Two chars were studied: hydrolytic reed lignin and hydrolytic wheat straw lignin.Isothermal experiments, using temperatures from 725°C to 825°C were conducted in a thermobalance. The atmosphere was 50%(volmol%) steam and 50%(vol%)N2. Additional tests at 10% and 20% of steam (N2as complement) were performed in order to determine the effect of steam partial pressure. Additional sample characterizations, such as the proximate and ultimate analyses of the two residues, as well as the metals content in chars, and morphological characterization were also performed. The apparent activation energy, Ea, of steam-char reaction was determined at different degrees of char conversion. The results showed that the Ea increases with conversion for both samples, ranging from 135 to 188 kJ/mol., Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 549-552

Hydrolytic Lignin rich residue (HL) produced in house activities of wheat straw biorefining and commercial Distiller's Dried Grains with Solubles (DDGS) can be considered as potential feedstock for energy production via combustion or gasification because their relatively high heating values. The residues were analyzed to determine their proximate and ultimate composition together with the heating values. The raw residues and the chars obtained from them at 900°C were investigated by TGA under oxidizing atmospheres (mixtures of N2 and O2) to determine the pyrolysis and combustion behaviors, included the activation energy of combustion at low temperature. The kinetic data obtained at this microscale are useful to design and model the thermal conversion in fixed bed gasifiers, downdraft or updraft. Significant differences were pointed out both between the thermal behavior of the raw residues and between their chars. However, the activation energy of combustion resulted 120 kJ/mol for both chars, in agreement with literature on biomass derived chars. The biochemical composition, in particular the higher content of protein in DDGS, was considered to explain the different kinetics., Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 667-670

In this work the combustion behavior of lignin-rich solid residue from reed (Arundo donax) was investigated in atmospheres of oxygen, i.e. 21 kPa and 101 kPa. The residue derived from processing reed that was pretreated by continuous steam explosion, then hydrolyzed by enzymes, recovered by filtration and dried. The lignin residue was analyzed to determine volatile and fix carbon, ash, C, O, H, N, S, Cl, LHV and HHV. The kinetic parameters for combustion of the char obtained from it by pyrolysis at 900°C were determined by TGA in the range 360 °C-380 °C and pO2 21 kPa-101 kPa. The activation energy resulted 120 kJ/mol in agreement with literature data on chars derived from biomass. The reaction order resulted 0.5 and is consistent with a chemical controlled regime, with dissociative adsorption of the O2 molecule., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 1129-1131