209 research outputs found

    Effect of ultrasonic post-treatment on anaerobic digestion of lignocellulosic waste

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    This paper evaluates the effects of ultrasonication (US) applied, individually or in combination with a mechanical treatment, to the effluent of anaerobic digestion (AD) of lignocellulosic waste, on methane (CH4) production. US of the substrate downstream of AD is a relatively novel concept aimed at improving the degradation of recalcitrant components in order to enhance the overall energy efficiency of the process. US tests were carried out on real digestate samples at different energies (500−50,000 kJ/kg total solids (TS), corresponding to sonication densities of 0.08−0.45 W/ml). AD tests were performed on mixtures of sonicated (Sus) and untreated (S) substrate at two different Sus: S ratios (25:75 and 75:25 w/w), simulating post-sonicated material recycling to the biological process. The US effect was estimated through the solubilization degree of organic matter, as well as the CH4 production yield and kinetics, which were all found to be enhanced by the treatment. At Sus: S = 75:25 and Es ≥ 20,000 kJ/kg TS (0.25 W/ml), CH4 production improved by 20% and the values of the kinetic parameters increased by 64–82%

    Possibilities for the use of sludge from a drinking water treatment plant at ggaba iii in kampala, Uganda

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    Sludge from the drinking water treatment plant at Ggaba III, located in Kampala (Uganda), was tested to evaluate the feasibility of two valorization routes, for building material and Solid Recovered Fuel (SRF) production. The aim of the research was to divert the huge amount of sludge produced every year, approximately equal to 2,140 metric tons of TSS/year, from landfilling. The average high heating value of the sludge was 8.44 MJ/kg TS, corresponding to the lower value of the interval of variation typically reported for other biosolids (8.0-23 MJ/kg). Different bricks were prepared at sludge to clay ratios of 0, 0.05, 0.1, 0.3 and 0.5 by weight. For each mixture composition, bricks of nominal size 215 x 102.5x 65mm were prepared by hand and fired for 6hrs in a Hoffman kiln at temperatures: 850°C, 900°C, 950°C, 1000°C and 1050°C. The bricks produced with a sludge to clay ratio of 0.1 fired at temperatures of ≥980°C met the compressive strength of 3N/mm2 for common bricks according to Ugandan Standard (US) 102:1995. These results suggest that water treatment sludge at Ggaba is more suitable for the production of common bricks than using it as an energy source. Given the encouraging results that make the studied valorization route applicable in an emerging economy country as Uganda, further investigations are required to assess the leaching behaviour and stability of the mechanical properties over time

    BBCircle – Life Cycle Assessment for innovative biorefinery process evaluation

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    The BBCircle project1, funded by the Lazio Region (IT), is aimed at integrating different processes to produce biomaterials, biofuels, capturing CO2 and promote circularity, in reference to the suitable and available substrates in the regional territory. Please click Additional Files below to see the full abstract

    Electrokinetic remediation of metal-polluted marine sediments: experimental investigation for plant design

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    This paper presents the results of an extensive set of laboratory experiments performed to design a demonstrative electrokinetic plant for extracting heavy metals from marine sediments dredged from the Livorno marine harbour. The investigated sediments displayed a high salinity, a high acid neutralization capacity, a low electrical resistivity (0.5 Ωm), a high alkalinity (pH ≈ 8) and a large fraction of fine particles. The target metals were Cd, Cr, Cu, Ni, Pb and Zn at relatively weak and inhomogeneous concentrations with high non-mobile fractions. After an accurate characterization, several screening and full electrokinetic tests were performed using cells of two different sizes, several conditioning agents (HNO3, HCl, H2SO4, citric acid, oxalic acid, ascorbic acid, EDTA), different applied current intensities and durations. The tests highlighted the need for long treatment times in order to obtain a significant pH reduction, with some appreciable metal removal being attained only after several weeks. The best results were obtained with strong acids used as the conditioning agents, with significant specific effects of each acid, including pronounced resistivity increase (from 0.5 up to 10 Ωm) and a high electroosmotic flow (EOF) with H2SO4, or a reversed EOF (electroendosmosis), and minor resistivity changes with HNO3. The use of the obtained data to design a demonstrative plant is also presented in the paper, with considerations on operating parameters such as energy and reagent consumption, characteristics of plant components and required safety measures. buffer capacity, conditioning agent

    Safety and effectiveness of gemcitabine for the treatment of classic Kaposi’s sarcoma without visceral involvement

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    Background: Classic Kaposi’s sarcoma (CKS) is a rare, multifocal, endothelial cell neoplasm that typically occurs in elderly people with previous infection by human herpes virus-8. Prospective trials are rare, and the choice of drugs relies on prospective trials performed on HIV-associated Kaposi’s sarcoma (KS). Pegylated liposomal anthracyclines and taxanes are considered the standard first- and second-line chemotherapy, respectively. Despite the indolent biologic behavior, the natural history is characterized by recurrent disease. This condition of chronic administration of cytotoxic drugs is often associated with immediate/long-term adverse events. Methods: This was an observational, retrospective study to evaluate the effectiveness and safety of gemcitabine in patients with CKS. From January 2016 to September 2021, the patients were treated with gemcitabine 1000 mg/m2 on days 1 and 8, with cycles repeated every 21 days. The treatment was administered as first or second line. Results: Twenty-seven (27) patients were included in the study. Twenty-one (21) out 27 patients (77.8%) achieved a partial response (PR), including 8 patients with major response (MR) (29.6%) and 13 patients with minor response (mR) (48.2%); 2 (7.4%) showed a complete response (CR), 3 (11.1%) a stable disease (SD), and 1 (3.7%) a progressive disease (PD). Tumor responses were generally rapid, with a median time to first response of 4 weeks (range, 3–12 weeks). Patients who responded had disease improvement with flattening of the skin lesions, decrease in the number of lesions, and substantial reduction in tumor-associated complications. Median duration of response was 19.2 months. Common adverse events were grades 1/2 thrombocytopenia, and grade 1 noninfectious fever. No patient discontinued treatment as a result of adverse events. Conclusion: Our study showed that gemcitabine is effective and well tolerated, acts rapidly on cutaneous lesions, and allows substantial symptom palliation, without dose-limiting toxicity. Gemcitabine represents a safe and effective option for the treatment of CKS

    Enhanced Separation of Incinerator Bottom Ash. Composition and Environmental Behaviour of Separated Mineral and Weakly Magnetic Fractions

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    Abstract: The paper reports an investigation on the compositional characteristics and environmental behaviour of eight fractions deriving from an advanced separation process applied to waste incineration bottom ash to recover ferrous and non-ferrous metals. Specifically, five mineral fractions and three weakly magnetic mixed metal/mineral fractions were analyzed for their physical properties, chemical composition and leaching behaviour in order to assess their recycling potential and estimate the expected environmental impacts. While the mineral fractions were found to contain only small amounts of undesired waste glass fragments, the weakly magnetic materials turned out to be commingled with a consistent portion of mineral components, resulting in a heterogeneous mixture with limited utilization potential. Their bulk and chemical composition as well as leaching properties were strongly affected by the presence of mineral particles associated with molten magnetic metals. The most critical elements with a view to leaching turned out to be, for both the mineral and the weakly magnetic fractions, Sb and Cr, which exceeded the quality standards for inert waste disposal in landfills. Graphic Abstract: [Figure not available: see fulltext.
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