1,510 research outputs found
Carte de Visite from Marchese Giuseppe Cavalletti to Hagan
No full textPrinted carte de visite from Marchese Giuseppe Cavalletti, Piazza S.Eustachio 83 (Rome), for [Hagan]
Profilo di un collezionista cremonese tra Settecento e Ottocento: il marchese Giuseppe Sigismondo Ala Ponzone di Cremona
No full textBiografia culturale del marchese Giuseppe Sigismondo Ala Ponzone 1771-1842, con particolare attenzione alla ricostruzione della sua attività di collezionist
EFFFECT OF LEACHING BEHAVIOUR BY QUENCHING OF BOTTOM ASH FROM MSW INCINERATION
No full textAbstract
Bottom ashes obtained from a municipal solid waste incineration plant, have shown different pH and lead concentrations in
leachate for different lines. In order to explain this behaviour, combustion tests were performed concerning the lines and the
effect of the type of wastes. The BA obtained from the same waste has shown the same raw chemical composition, but
different leachate characteristics for the different lines. The bottom ash from different wastes burned on the same line instead
showed very similar leaching behaviour. The results suggest that the quality of leach ate depends on the plant and process
conditions (in particular the ash quenching phase) and not on the composition of the waste. During ash quenching, the
formation and dissolution of soluble alkalis depends on the washing ratio and on the residence time. A different washing
degree leads to a different residual alkalinity in the bottom ash, and consequently to a different value of leachate pH with
different metal releases. Therefore, with the practical aim of establishing the best conditions for the final disposal of bottom
ash, a careful planning of this phase could be proposed as an alternative to a weathering process
Evaluation of Nitrogen Non-Point Sources in Po River Near Turin
No full textThe non-point hydraulic and nitrogen loads in the stretch of Po river upstream and downstream from the city of Turin have been investigated, on the basis of regular data concerning quality and flow rates in the river in different periods of a reference year. The collected data have been organized in terms of hydraulic and mass balances, taking into account input points, affluents and withdrawals, and the missing terms as concern non-point loads or transfer phenomena with surrounding banks and connected aquifers have been identified.From the nitrogen speciation it was possible to distinguish between different contributions to river load, and to estimate presence of agricultural loads, run-off phenomena from impervious urban areas, aquifer connections. All these information can be useful for a better assessment of the surrounding territory in order to improve river quality for different uses
Full scale tests of short-term municipal solid waste incineration bottom ash weathering before landfill disposal
No full textProblem statement: Natural weathering is the most economic method of treatment in order to reduce the release of heavy metals present in the residue. Approach: The aim of the study was to optimize the minimum weathering times that were useful to reduce the lead release to within the Italian limits for landfill disposal. The mechanism of short-term weathering of MSWI bottom ash had been studied and its effect on the leaching of lead had been evaluated. Two bottom ash heaps had been realized for the experimental assessment: In one case an open-air situation was used, in the other, a heap placed under shelter was not exposed to rain. Results: The weathering course was monitored through the results of a leaching test that was carried out at different ageing times (EN 12457-2:2002). The total carbonates were also measured, at the same time, on the fine fraction of the weathered bottom ash (<1 mm). A fast decrease in lead release was observed in the analysis of the leachates and, at the same time, a decrease in pH and calcium concentration. The pH and leachate lead concentration control mechanisms were investigated and individuated. It had been possible to observe that the lead concentration was fundamentally a function of the pH. The Calcite precipitation that occurred from calcium hydroxide carbonation was the main reason for the decrease above all during the first days of the process, when the maximum quantity of CO2 was fixed by air. The pH value was controlled by Portlandite dissolution only at the beginning, after the pH control seems to be due to aluminum hydroxides. Conclusion: The most significant changes in the bottom ash were found to occur in the first 60 days. It had been possible to verify the limited influence of washing phenomena while it was confirmed that carbonation was the most important process in short-term weathering and that it had an important rule on limiting lead release
Caratterizzazione del rilascio delle scorie in relazione alle diverse condizioni del processo di incenerimento di RSU
No full text
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