Catarinense Institute of Environmental Research and Human Development IPADHC

Conde, Brazil

Catarinense Institute of Environmental Research and Human Development IPADHC

Conde, Brazil
SEARCH FILTERS
Time filter
Source Type

Silva L.F.O.,Centro Universitario Univates | Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | DaBoit K.,Catarinense Institute of Environmental Research and Human Development IPADHC | Sampaio C.H.,Federal University of Rio Grande do Sul | And 6 more authors.
Science of the Total Environment | Year: 2012

Low-rank, high-mineral matter Bulgarian coals were studied using a variety of chemical, optical, and electron beam methods. The larger fly ash carbon phases include charred carbons in contrast to coked carbons present in the fly ashes of bituminous-coal-derived fly ashes. Nanoscale carbons include multi-walled carbon nanotubes (MWCNTs) encapsulating Hg, Se, and As, among other elements. In addition to the glass which dominates the fly ash, relatively coarse 'rock fragments', consisting of an unmelted to partially melted core surrounded by a glassy rim, are present in the fly ash. Nano-scale minerals can contain hazardous elements and, along with metal-bearing multiwalled nanotubes, can be a path for the entry of hazardous particles into the lungs and other organs. © 2011 Elsevier B.V.


Oliveira M.L.S.,Catarinense Institute of Environmental Research and Human Development IPADHC | Ward C.R.,University of New South Wales | Izquierdo M.,British Geological Survey | Sampaio C.H.,Federal University of Rio Grande do Sul | And 7 more authors.
Science of the Total Environment | Year: 2012

The extraction of sulphur produces a hematite-rich waste, known as roasted pyrite ash, which contains significant amounts of environmentally sensitive elements in variable concentrations and modes of occurrence. Whilst the mineralogy of roasted pyrite ash associated with iron or copper mining has been studied, as this is the main source of sulphur worldwide, the mineralogy, and more importantly, the characterization of submicron, ultrafine and nanoparticles, in coal-derived roasted pyrite ash remain to be resolved. In this work we provide essential data on the chemical composition and nanomineralogical assemblage of roasted pyrite ash. XRD, HR-TEM and FE-SEM were used to identify a large variety of minerals of anthropogenic origin. These phases result from highly complex chemical reactions occurring during the processing of coal pyrite of southern Brazil for sulphur extraction and further manufacture of sulphuric acid. Iron-rich submicron, ultrafine and nanoparticles within the ash may contain high proportions of toxic elements such as As, Se, U, among others. A number of elements, such as As, Cr, Cu, Co, La, Mn, Ni, Pb, Sb, Se, Sr, Ti, Zn, and Zr, were found to be present in individual nanoparticles and submicron, ultrafine and nanominerals (e.g. oxides, sulphates, clays) in concentrations of up to 5%. The study of nanominerals in roasted pyrite ash from coal rejects is important to develop an understanding on the nature of this by-product, and to assess the interaction between emitted nanominerals, ultra-fine particles, and atmospheric gases, rain or body fluids, and thus to evaluate the environmental and health impacts of pyrite ash materials. © 2012 Elsevier B.V.


Silva L.F.O.,Centro Universitario Univates | Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | Sampaio C.H.,Federal University of Rio Grande do Sul | Guedes A.,University of Porto | And 2 more authors.
Fuel | Year: 2012

A routine multianalytical methodology based on the combination of Optical Microscopy (OM) with instrumental microscopic techniques like Electron Microscope (HR-TEM and SEM) coupled to Energy Dispersive X-Ray Spectroscopy (EDS), Confocal Microscopy (CM) and Micro-Raman Spectroscopy (MRS) provides a powerful approach for the research of the mineralogical composition. Coals from different origins (five continents) and different mineralogical composition were selected for analysis. The analytical approach makes use of OM to select the different mineral phases associated to coal samples with subsequent use of the instrumental microscopic techniques on selected targets. The SEM/EDS, HR-TEM/EDS, and MRS analysis showed no significant differences in the chemical composition of the main minerals found associated to coal, such as oxides, sulphides, sulphates, silicates, carbonates, and others. The instrumental techniques provide fast, non-destructive and highly-selective analysis of both the whole coal and particle surfaces. Moreover, thermodynamic speciation through chemical modelling simulations gives the required information to confirm the stability of secondary minerals detected in the samples and helps to diagnose the potential environmental risks associated with weathering. © 2011 Elsevier Ltd. All rights reserved.


Quispe D.,University of Huelva | Perez-Lopez R.,University of Huelva | Perez-Lopez R.,CSIC - Institute of Environmental Assessment And Water Research | Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | And 2 more authors.
Fuel | Year: 2012

This paper reports about changes in mobility of hazardous elements contained in coal during combustion at a power plant in Santa Catarina (Brazil) and the environmental impact potential of ashes. Total and mobile element concentrations were determined by digestion and sequential extraction. Comparison of results within the mobile fraction showed that after combustion, oxidizable elements bound to organic matter and sulfides in coal were mostly transformed into elements easily soluble in water or slightly acidic conditions and, hence, most readily bioaccumulative in the environment in ashes, mainly U, Cr, and As. Capacity of ashes as a source of mobile pollutants was quantified by combining sequential extraction and annual production. Just considering the easily soluble fraction, coal ashes could leach up to 839 tons of Al, 144 tons of Fe, 100 tons of Mn, 4.6 tons of Zn, 3.1 tons of Cr, 1.7 tons of As, 1.5 tons of Cu, 490 kg of U, and 20 kg of Pb every year. Bottom ashes are disposed of in landfill sites close to the plant. Fly ashes are recycled as construction material. Diagnostic processes do not consider checking for these highly mobile hazardous elements. Hence, uncontrolled dumping and use of these by-products may pose significant risks to environment and human health. © 2011 Elsevier Ltd. All rights reserved.


Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | Querol X.,CSIC - Institute of Environmental Assessment And Water Research | da Boit K.M.,Catarinense Institute of Environmental Research and Human Development IPADHC | Vallejuelo S.F.O.D.,University of the Basque Country | Madariaga J.M.,University of the Basque Country
Journal of Hazardous Materials | Year: 2011

Fenton's reaction is proposed as an accelerated weathering test for sulphides associated with Brazilian Coal Mining Residues (CMR), that are exposed to oxygen and water during the mining of coal. TEM and SEM/EDX were used to evaluate the nature, occurrence and distribution of minerals in remaining coals and other lithological units, before and after applying the test. Oxidation of CMRs was examined by analyzing soluble sulphur (sulphate) and dissolved metals by ICP-MS or ICP OES. As dissolved sulphate increases, dissolved Zn, Cd, Cu and Co concentrations increase, leading to undetectable amounts in the remaining solid phases; dissolved Ni and Mn also increase with the mobilized sulphur, but the remainder in the solids is the most important fraction; Fe and Pb are not mobilized due to precipitation as jarosite or hematite in the case of Fe or as sulphate in the case of Pb. Agreement between the observed results and the predictions by geochemical modelling is discussed. © 2010 Elsevier B.V.


Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | Hower J.C.,University of Kentucky | Izquierdo M.,CSIC - Institute of Environmental Assessment And Water Research | Querol X.,CSIC - Institute of Environmental Assessment And Water Research
Science of the Total Environment | Year: 2010

Phosphogypsum (CaSO4·2H2O), a by-product of phosphate-rock processing, contains high amounts of impurities such P2O5, F, radioactive elements, organic substances, secondary nanominerals, and ultrafine particles (UFP) enriched in metals and metalloids. In this study, we examine phosphogypsum (PG) collected from abandoned fertilizer industry facility in south Brazil (Santa Catarina state). The fragile nature of nanominerals and UFP assemblages from fertilizer industry systems required novel techniques and experimental approaches. The investigation of the geochemistry of complex nanominerals and UFP assemblages was a prerequisite to accurately assess the environmental and human health risks of contaminants and cost-effective chemical and biogeological remediation strategies. Particular emphasis was placed on the study and characterization of the complex mixed nanominerals and UFP containing potentially toxic elements. Nanometer-sized phases in PG were characterized using energy-dispersive X-ray spectrometer (EDS), field-emission scanning electron microscope (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM) images. The chemical composition and possible correlations with morphology of nanominerals and UFP, as well as aspects of nanominerals and UFP, are discussed in the context of human health exposure, as well as in relation to management of the nanominerals and UFP in PG environments. © 2010 Elsevier B.V.


Ribeiro J.,University of Porto | Taffarel S.R.,University of la Salle of Colombia | Sampaio C.H.,Federal University of Rio Grande do Sul | Flores D.,University of Porto | And 2 more authors.
International Journal of Coal Geology | Year: 2013

The coal (anthracite A) in Douro Coalfield (NW of Portugal) has been exploited for many years and has been mainly used as fuel supply by a thermal power plant. The mining activities inevitably impacted the environment, which includes a large number of coal waste piles emplaced over the old mine sites and adjacent areas of the Douro Coalfield. The disposal of coal mining residues represents significant environmental concerns due to their potential influence on soils and sediments, as well as on the surface and groundwater of the surrounding areas. In the present study, the development of sequential extraction combined with various advanced analytical techniques was performed to provide an improved understanding of the complex processes related with sulfide-rich coal waste oxidation, sequences of mineral formation, and the transport mechanisms of hazardous elements by specific neoformed soluble minerals. The results showed the presence of amorphous iron (oxy-) hydroxides and goethite with various degrees of crystallinity, containing hazardous elements, such as As, Cr, Hg, Mo, Se, Pb, U, and others. Some of the neoformed minerals found in the coal waste material are the same as those commonly associated with coal acid drainage, in which oxidation of sulfides plays an important role. The precipitated neoformed minerals include pickeringite, blödite, and a mixture of epsomite, pickeringite, and hexahydrite. As these sulfates may dissolve after the first rain, they may release above-mentioned elements into surrounding water bodies. © 2013 Elsevier B.V.


Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | Oliveira M.L.S.,Catarinense Institute of Environmental Research and Human Development IPADHC | Neace E.R.,Morehead State University | O'Keefe J.M.K.,Morehead State University | And 2 more authors.
International Journal of Coal Geology | Year: 2011

Mineral sublimates from the Ruth Mullins fire in abandoned underground and surface mines in the high volatile A bituminous Middle Pennsylvanian Hazard No. 7 coalbed, Perry County, Kentucky, were examined by optical mineralogy, X-ray diffraction (XRD), and high-resolution-transmission electron microscopy (HR-TEM). Optical examination revealed the presence of salammoniac and a fine, unidentified fibrous mineral. XRD also showed the presence of salammoniac, along with trace amounts of quartz, kaolinite, and, possibly, phengite. Both cubic and dendritic salammoniac forms were observed with HR-TEM. Gypsum, jarosite, with cubic pseudomorphs after pyrite, and Fe-minerals, including Cr-bearing hematite in association with jarosite, were observed with HR-TEM. Dehydration of jarosite can lead to the formation of less hydrous Fe-sulfates and hematite. © 2010 Elsevier B.V.


Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | Wollenschlager M.,Catarinense Institute of Environmental Research and Human Development IPADHC | Oliveira M.L.S.,Catarinense Institute of Environmental Research and Human Development IPADHC
Environmental Geochemistry and Health | Year: 2011

The concentrations and loadings of major and trace elements in coal mine drainage (CMD) from 49 abandoned mines located in the coal fields of the Brazilian state of Santa Catarina were determined. The CMD sites typically displayed a wide spatial and temporal variability in physical and geochemical conditions. The results of our CMD analyses in Santa Catarina State were used to illustrate that the geochemical processes in the rock piles can be deduced from multiple data sets. The observed relationship between the pH and constituent concentrations were attributed to (1) dilution of acidic water by near-neutral or alkaline groundwater and (2) solubility control of Al, Fe, Mn, Ba and Sr by hydroxide, sulfate, and/or carbonate minerals. The preliminary results of the CMD analyses and environmental health in the Santa Catarina region, Brazil, are discussed. © 2010 Springer Science+Business Media B.V.


Cerqueira B.,University of Vigo | Vega F.A.,University of Vigo | Serra C.,University of Vigo | Silva L.F.O.,Catarinense Institute of Environmental Research and Human Development IPADHC | Andrade M.L.,University of Vigo
Journal of Hazardous Materials | Year: 2011

Relatively new techniques can help in determining the occurrence of mineral species and the distribution of contaminants on soil surfaces such as natural minerals and organic matter.The Bt horizon from an Endoleptic Luvisol was chosen because of its well-known sorption capability. The samples were contaminated with Cu 2+ and/or Pb 2+ and both sorption and desorption experiments were performed. The preferential distribution of the contaminant species ( 63Cu and 208Pb) to the main soil components and their associations were studied together with the effectiveness of the surface sorption and desorption processes. The results obtained were compared with non-contaminated samples as well as with previous results obtained by different analytical techniques and advanced statistical analysis. Pb 2+ competes favorably for the sorption sites in this soil, mainly in oxides and the clay fraction. Cu 2+ and Pb 2+ were mainly associated with hematite, gibbsite, vermiculite and chlorite.This study will serve as a basis for further scientific research on the soil retention of heavy metals. New techniques such as spectroscopic imaging and transmission electron microscopy make it possible to check which soil components retain heavy metals, thereby contributing to propose effective measures for the remediation of contaminated soil. © 2011 Elsevier B.V.

Loading Catarinense Institute of Environmental Research and Human Development IPADHC collaborators
Loading Catarinense Institute of Environmental Research and Human Development IPADHC collaborators