Search results for "ash"

Stabilisation of MSWI bottom ash with sulphide-rich anaerobic effluent.

2007

Effluent of an anaerobic sulphate-reducing wastewater treatment process was used to stabilise bottom ash. The effect of stabilisation on the concentration and binding of Ca, P, S, Cu, Pb, Zn, As, Cr, and Mo were studied by comparing results of sequential extraction from fresh and stabilised bottom ash. The stabilisation treatment improved the retention of Ca, Cu, Pb, S, and Zn in bottom ash compared to a treatment with ion-exchanged water. In addition to retention, Cu, S, and Zn were accumulated from the anaerobic effluent in the bottom ash. Concentrations of As, Cr, and Mo remained on the same level, whereas leaching of P increased compared to control treatment with ion-exchanged water. Im…

Colloidal stability of nanoparticles derived from simulated cloud-processed mineral dusts

2013

AbstractLaboratory simulation of cloud processing of three model dust types with distinct Fe-content (Moroccan dust, Libyan dust and Etna ash) and reference goethite and ferrihydrite were conducted in order to gain a better understanding of natural nanomaterial inputs and their environmental fate and bioavailability. The resulting nanoparticles (NPs) were characterised for Fe dissolution kinetics, aggregation/size distribution, micromorphology and colloidal stability of particle suspensions using a multi-method approach. We demonstrated that the: (i) acid-leachable Fe concentration was highest in volcanic ash (1mMg−1 dust) and was followed by Libyan and Moroccan dust with an order of magnit…

Technogenic Magnetic Particles in Alkaline Dusts from Power and Cement Plants

2012

During this study, we investigated the mineralogical characterization of technogenic magnetic particles (TMPs) contained in alkaline industrial dust and fly ash emitted by coal burning power plants and cement plants. The reaction of tested dust samples varied between values of pH 8 and pH 12. Their magnetic properties were characterized by measurement of magnetic susceptibility (χ), frequency dependence of magnetic susceptibility (χ(fd)), and temperature dependence of magnetic susceptibility. Mineralogical and geochemical analyses included scanning electron microscopy with energy dispersive spectroscopy, microprobe analysis and X-ray diffraction. The TMPs in fly ash from hard coal combustio…

Treatment of leachate from MSWI bottom ash landfilling with anaerobic sulphate-reducing process

2007

Abstract Removal of sulphate and toxic elements from the leachate of a field landfill lysimeter ( 112 m 3 ) , containing municipal solid waste incineration (MSWI) bottom ash, was studied. The leachate was treated in two parallel laboratory upflow anaerobic sludge blanket (UASB) reactors without and with ethanol as additional carbon source. With ethanol more than 65% of sulphate was removed, while without ethanol removal was negligible. The treatment removed Ba, Ca, Cu, Mn, Mo, Ni, Pb, Tl, Sb, Se, Sr, and Zn of the studied 35 trace and other elements. The sequential extraction of the reactor sludge at the end of runs confirmed that with a few exceptions (Ba, Ca, and Cu) the main mechanism by…

Chlorinated dioxins and dibenzothiophenes in fly ash samples from combustion of peat, wood chips, refuse derived fuels and liquid packaging boards

1995

Abstract Peat, wood chips, refuse derived fuel and liquid packaging board in different combinations were burned at a temperature of at least 850 °C. Fly ash samples from these combustions were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzothiophenes (PCDBTs) by high resolution GC/MS. The concentrations of tri- and tetrachlorodibenzothiophenes and tri-, tetra- and pentachlorodioxins were highest when mixtures of wood chips and refuse derived fuel (RDF) were burned. The fly ash from the combustion of pure peat pellets did not contain any polychlorinated dibenzothiophenes. When wood chips and RDF were burned the concentrations of chlorinated compounds in fly…

Photocatalytic activity of TiO2/SiO2 systems

2009

Silica-supported TiO(2) powders were synthesized by a wet method under mild conditions. The aim of the work was the preparation of TiO(2)/SiO(2) additives for photocatalytic cements. Three types of commercial SiO(2) were used as supports: Cabot, Axim and Fly Ash. Cabot silica was ultra-pure whereas the other two silica contained different percentages of various oxides. The TiO(2)/SiO(2) samples, denoted TiO(2)/Cabot, TiO(2)/Axim and TiO(2)/Fly Ash, were prepared by boiling suspensions obtained by addition of silica to a solution of TiCl(4) in water (volume ratio 1:10). The photocatalytic activity was evaluated in a gas-solid system both in batch and in continuous reactors using 2-propanol a…

Napoleon in Central Finland: The Fashion of Giving Children Rulers’ Names

2012

Crash modeling for urban roundabouts: a case study

2013

In many cities and towns, a large number of intersections are considered sites with promise for safety and operational improvements. Several studies have been carried out in many countries to establish relationships between crashes and flow and non-flow explanatory variables, using statistical tools to investigate factors critical to road safety. Starting from a brief review of existing information and analysis on the issue, this article summarizes the findings of an exploratory analysis aimed at modeling injury crashes for a sample of urban roundabouts. The methodological path followed in this research allowed to handle issues associated with the estimation of a safety performance function…

Mathematical modeling and parameters estimation of a car crash using data-based regressive model approach

2011

Author's version of an article in the journal: Applied Mathematical Modelling. Also available from the publisher at: http://dx.doi.org/10.1016/j.apm.2011.04.024 n this paper we present the application of regressive models to simulation of car-to-pole impacts. Three models were investigated: RARMAX, ARMAX and AR. Their suitability to estimate physical system parameters as well as to reproduce car kinematics was examined. It was found out that they not only estimate the one quantity which was used for their creation (car acceleration) but also describe the car's acceleration, velocity and crush. A virtual experiment was performed to obtain another set of data for use in further research. An A…

Rendre la mode transparente au consommateur : mais quoi montrer ?

2021

La transparence dans le domaine de la mode semble paradoxale. Nous avons cherché à comprendre comment les informations peuvent être plus transparentes pour les consommateurs. A l'exemple du modèle de la transparence numérique proposé par Portes et al (2020), nous avons identifié les trois dimensions : l'information objective dans le domaine de la mode semble être : le prix, les matières premiers, le lieu de production ; limpidité : les consommateurs souhaitent connaitre comment le prix est affecté dans la chaine de production par exemple ; et ouverte, parce que le consommateur souhaite échanger avec la marque. Nous avons également rencontré les conséquences d'engagement et de confiance. A d…