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The waste generated by the global fishing industry, such as fish scales, is mostly considered useless and discarded in a disorderly and/or unplanned way in inappropriate places, posing serious risks to both the environment and human health. This study proposes the use of fish scales in combustion processes as an alternative for such residues and to avoid their exposure in urban areas. Combustion experiments were conducted in a drop tube furnace (DTF), and the factors temperature, residence time, and sample particle size were investigated. The main atmospheric pollutants (CO, NO, CO2, and SO2) and the residues generated from the combustion processes were characterized by FTIR, EDS and ICP-OES analyses, and SEM images. The samples showed better performance at 1100 °C and 500 -ms residence time, when the burnout reached 96%, and particle size greater than 300-μm and 300-ms residence time led to the worst combustion performance (24.45% burnout), with the highest CO and NO peaks, indicating incomplete combustion of the fish scales. The analysis of the residues revealed total decomposition of the organic matter at temperatures above 700 °C and formation of hydroxyapatite. According to the DTF results, the use of fish scales in firing processes is a viable treatment of the residues, generating energy and avoiding environmental problems caused by inadequate disposal. [ABSTRACT FROM AUTHOR]

In this study, the microwave-induced combustion (MIC) method was evaluated for the sample preparation of the most consumed mushroom species in Brazil (Champignon, Shiitake, and Shimeji) and further halogen determination by ion chromatography (IC). For this, sample mass, combustion aid mass, and absorbing solution (H2O and 50 mmol·L−1, 100 mmol·L−1, or 150 mmol·L−1 NH4OH) were evaluated. Bromine and iodine concentrations, determined by IC, were lower than the limits of detection (LODs, Br: 6 mg·kg−1 and I: 24 mg·kg−1). Inductively coupled plasma mass spectrometry (ICP-MS) was also used for Br and I determination, and the LODs were lower (Br: 0.066 mg·kg−1 and I: 0.014 mg·kg−1) than those obtained by IC. Concentrations of Cl, obtained by IC, ranged from 523 mg·kg−1 to 13053 mg·kg−1 with LOD of 40 mg·kg−1. In turn, Br and I concentrations, obtained by ICP-MS, ranged from 2.49 mg·kg−1 to 5.50 mg·kg−1 and from <0.014 mg·kg−1 to 0.047 mg·kg−1, respectively. Fluorine concentrations, determined by IC, were always lower than LOD (23 mg·kg−1). The trueness of the proposed methods was evaluated by recovery tests using standard solutions and a reference material (RM NIST 8435). When using the standard solution, recoveries ranged from 95% to 103% for halogen determination by IC and from 105% to 109% for Br and I determination by ICP-MS. When using the RM, recoveries of 102% for Cl by IC and of 87% and 86% for Br and I by ICP-MS, respectively, were obtained. [ABSTRACT FROM AUTHOR]

Rice husk is a type of waste widely generated in Brazil and worldwide. It is often applied as biomass for energy generation. Rice husk ash (RHA), a solid waste generated in the combustion process for energy generation, is comprised primarily of silica and carbon. In this study, two types of RHAs, obtained by different industrial combustion processes (moving grate furnace and fluidized bed), were subjected to chemical or thermal treatments in different atmospheric flows (Ar/H 2 , N 2 , O 2 gases, compressed air, and vacuum). The particle size, specific weight, surface area, electrical properties, crystalline structure, and chemical composition were analyzed by different characterization techniques. The results indicated that thermal treatments generate powders with a high silica content; amorphous structures were found in some silica materials (those obtained by chemical treatment and thermal treatments in Ar/H 2 flow, compressed air, and vacuum), and others were crystalline in the cristobalite phase (mainly samples treated in the O 2 and N 2 atmospheric flows). The yield of each process varied, obtaining silica concentrations above 99.3%. Samples with significant analytical carbon content showed higher values of electrical conductivity; this result is probably due to the incorporation of carbon atoms into the cristobalite lattice. Samples treated with O 2 atmospheric flows showed resistivity values of 1008 Ω.cm with very low carbon levels. This work concluded that carbonaceous silica materials (which may be new materials in the Si-C-O system) may be obtained during the thermal treatments of rice husk ash. [Display omitted] • Thermal and chemical treatments of rice husk ash. • Mechanism of electrical conductivity of RHA compacted granulated samples. • Physical, chemical, and electric properties of carbonaceous silica materials from RHA. • High-added value and low-cost materials using potential co-products. [ABSTRACT FROM AUTHOR]

In recent years, the Brazilian government has been applying several restrictions with regard to preventing environmental pollution. Although Brazilian legislation is becoming stricter as to the pre-harvest burning of sugarcane, this practice is frequently used in order to assist manual harvesting. In the northeast region of Brazil, sugarcane is an important crop, which accounts for about 15% of the national production in a total area of 1,060,660 ha, the average production being 51,119 kg per hectare. The pre-harvest burning of sugarcane generates smoke, which has a high concentration of atmospheric pollutants such as carbon dioxide (CO 2 ), carbon monoxide (CO), particulate matter (P.M. 2.5 and 10), polycyclic aromatic hydrocarbons (PAH), volatile organic compounds (VOC) and nitrogen oxides (NO X ). This article estimates the volume of CO, P.M. 2.5 and NO X generated and how they are dispersed in the atmosphere when this arises from the burning of sugarcane biomass in rural areas of Northeast Brazil, and does so by using AERMOD VIEW ® simulation software. Using the characteristics of the emissions and environmental (meteorological and topographical) data, quality air profiles based on pollutant dispersion were obtained. Three studies were taken into account in order to determine the relationship between pollutant dispersion and some parameters of the burning process, such as those for the spatial distribution of resources, the duration of pre-harvest burning and the influence of undertaking burning in different months. As to spatial distribution, to divide an area into small lots contributes to decreasing the maximum concentration of pollutants by 53% compared to burning a single area of equivalent size. The study of the burning duration indicated that doing so gradually (using a lengthier procedure) could decrease the maximum concentration of the pollutants by an inverse relation. The harvesting period in this region is between November and April. The pollutants dispersion process was greatest in February. April presented the worst dispersion conditions, and was associated with the highest pollutant concentrations. [ABSTRACT FROM AUTHOR]

Partial load operation of SI engines is conventionally achieved by the use of a throttle to control the airflow or air-fuel mixture into the engine. When the engine operates at partial load the throttle causes high pumping losses which has an effect on decrease of the engine efficiency. One of the possible ways to decrease the pumping losses during partial loads is to operate the engine under lean mixture condition. The limitation in this case can be misfiring of used fuel. The combustion limits can be extended by addition of hydrogen to the regular fuel. This work presents an analysis of use of hydrogen-methane taking into account aspects related to the efficiency and emission of pollutants. To carry out this study an experimental system composed of a SI engine was used. Two important differentials were used. First, the engine was supplied with simulated biofuels according to the typical biogas composition of the Brazilian landfills (Bio60); second, the system was operated in partial load, with the addition of H 2 , forming the HBio60 blend, in an attempt to increase efficiency and reduce pumping losses by increasing lambda value and variation in trottle position. The same aspects were evaluated with the engine operating with biogas composed of 95% of methane (Bio95) and in mixture with hydrogen (HBio95). The tests were performed at different ignition angles and air/fuel ratio. The results showed that adding H 2 allows the combustion limits to be extended, with an effective increase of indicated efficiency. On the other hand, the reduction of NO x emissions was greater than 95% in the lean mixture provided by the presence of H 2 . The idea is to encourage change in the control algorithm of SI engines typically fueled with natural gas and use the H 2 -methane blends as fuel. Furthermore, diesel-powered buses in Brazil could be converted to SI gas engines without the loss of efficiency. [ABSTRACT FROM AUTHOR]

This study determined the priority PAHs concentrations in diesel fuel sold in Brazil and in lubricant oil sampleted in different usage times. The solid phase extraction (SPE) techinique using florisil (magnesium silicate) as solid phase was used to separate the fraction containing aromatic components present in the diesel fuel and lubricating oil samples. The measurements were performed by gas chromatography coupled to mass spectrometry. The PAH priority profile in lubricant oil was similar to the PAH profile in diesel where Naphthalene, Phenanthrene and Pyrene were dominant. The PAHs concentration in Brazilian diesel fuel sample were compared with the emission factors of their PAHs respective in exhaust of a vehicle fueled with the same Brazilian diesel fuel in order to estimate how much of the PAHs present in diesel remains unchanged during combustion. The ratio between the PAHs emission factors in exhaust (μg L −1 diesel) and their respective concentrations in diesel fuel (μg L −1 ) ranged from 0.01 ± 0.02 to 0.05 ± 0.029, depending on the PAH. These values indicate that at least 95–99% of the PAHs identified in diesel fuel were destroyed, converted into other compounds during the combustion, and/or retained in the lubricant oil reservoir. On the other hand, PAHs with higher concentrations in diesel also had higher exhaust emission factors, which suggests that the PAHs from diesel have a contribution to total PAH emissions. Therefore, reducing the PAHs content in diesel will probably contribute to curbing emissions of these compounds and help improve air quality. [ABSTRACT FROM AUTHOR]

Rice husk is the main byproduct of industrial processing of rice, and is a widely used byproduct in Brazil and worldwide as biomass in energy production, reducing environmental impacts associated with improper disposal. The ash generated in rice husk combustion has potential economic applications in a variety of sectors. However, the properties of rice husk ash (RHA) are strongly dependent on the combustion method used. This study investigates the physical, chemical, thermal, mineralogical, and morphological characteristics of three types of RHA, produced according to three distinct methods (grate furnace, fluidized bed, and suspension/entrained combustion). The results confirmed that combustion conditions define the characteristics of each RHA, even though the raw material used was essentially the same. The main differences in the characteristics of the silica obtained were observed in the parameters specific surface area (between 11.35 and 39.27 m 2 g −1 ), SiO 2 (between 90.02 and 96.71 wt%), total carbon contents (between 2.18 and 8.63 wt%), and the structure of the silica produced (completely amorphous or partially crystalline). Morphological profiles, oxide chemical composition, and specific weight presented similar results. [ABSTRACT FROM AUTHOR]

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Highlights: [•] Quantification of residual automotive lubricant oil in diesel S-10 by HATR–MIR. [•] Models can be used to quantify residual lubricant oil adulteration in diesel S-10. [•] The PLS models were validated and showed very good linearity. [•] The methodology is a rapid and low-cost monitoring of the quality of S-10 diesel. [ABSTRACT FROM AUTHOR]

This work aimed to better understand how aerosol particles from sugar cane burning contribute to the chemical composition of the lower troposphere in an agro-industrial region of São Paulo State (Brazil) affected by sugar and ethanol fuel production. During a period of 21 months, we collected 105 samples and quantified 20 saccharides by GC–MS. The average concentrations of levoglucosan (L), mannosan (M), and galactosan (G) for 24-h sampling were 116, 16, and 11 ng m−3 respectively. The three anhydrosugars had higher and more variable concentrations in the nighttime and during the sugar cane harvest period, due to more intense biomass burning practices. The calculated L/M ratio, which may serve as a signature for sugar cane smoke particles, was 9 ± 5. Although the total concentrations of the anhydrosugars varied greatly among samples, the relative mass size distributions of the saccharides were reasonably constant. Emissions due to biomass burning were estimated to correspond to 69% (mass) of the sugars quantified in the harvest samples, whereas biogenic emissions corresponded to 10%. In the non-harvest period, these values were 44 and 27%, respectively, indicating that biomass burning is an important source of aerosol to the regional atmosphere during the whole year. [ABSTRACT FROM AUTHOR]

Highlights: [•] We assess future paths of carbon capture and storage in power generation in Brazil. [•] We assess different carbon taxes in integrated optimization energy planning model. [•] After 2035 the energy system changes deeply with hydropower potential depletion. [•] Coal-fired plants equipped with post-combustion CCS acquire importance after 2035. [•] After 2040, the main choice is IGCC plants equipped with selexol CCS. [Copyright &y& Elsevier]

Abstract: In the Candiota Coalfield, RS, Brazil the Candiota Superior and Inferior coal seams are at current time being mined for power generation. The current study characterizes the other seams of the deposit, which include the upper (S2–S9) seams, the Banco Louco (BL) seam and the lower (I1–I5) seams, which up to date have not been considered for power generation. The analytical techniques applied in this study include: sequence stratigraphic analysis of the coal-bearing interval, petrographical and chemical analyses of the coal seams, reactivity tests based on thermobalance experiments and studies on beneficiation. Sequence stratigraphic analyses: Sedimentological analyses identified four depositional systems in the study area: alluvial fan, fluvial, lagoon-barrier and shallow marine, with coal seams developed in Transgressive Systems Tract, Highstand Systems Tract, and Lowstand Systems Tract. Petrographical and chemical analyses: The petrographical analyses showed that the most abundant maceral in the coals is vitrinite, followed by inertinite and liptinite. The average vitrinite reflectance is indicative of subbituminous rank (0.41 % Rr). The values for ash yield range from 29.0 to 74.2wt.% (average 49.1wt.%), and for volatile matter contents vary from 13.5 to 29.5wt.% (average 19.9wt.%). Sulfur contents range from 0.4 to 8.1wt.% (average 1.9wt.%). The gross calorific values, as received basis, range from 841 to 3727cal/g (average 2632cal/g). Based on X-ray diffraction analysis the most abundant minerals in the coal seams are quartz, kaolinite, illite and k-feldspar. Reactivity studies: Thermogravimetric analyses carried out on fourteen seam channel samples showed differences in the combustion behavior of the seams, in particular for the inertinite-rich seams S8 and Banco Louco. The I2 seam analyzed from four of the eight exploration wells indicated very similar combustion properties based on the thermogravimetric analyses. Beneficiation tests: From the sink-float tests and proximate and ultimate analyses, washability curves were prepared for all upper, lower and BL seams (>20cm thick). These curves were plotted showing ash distribution and total sulfur content for a grain-size between 25.4mm and 2.0mm (Fraction A, −25.4+2.0mm) and for a grain-size between 2.0mm and 0.1mm (Fraction B, −2.0+0.1mm). These curves provided important information to a possible gravimetric beneficiation for both size fractions. However, the performance of such beneficiation mainly depends on both the Near Gravity Material (NGM) value and separation density of each seam, which are the main parameters analyzed. In addition, these curves showed low values of total sulfur content in any separation density. However, the densest fractions were not taken into consideration. Conclusion: The results of the chemical and petrological analyses as well as the studies on combustion and beneficiation characteristics suggest that the seams investigated in this study (S1–S9, BL, I1–I5) do have the potential for being used in power generation. [Copyright &y& Elsevier]

Abstract: Flex-Fuel vehicles, launched in the Brazilian market in 2003, operate with gasoline blended with anhydrous ethanol (18–25% vol/vol), 100% hydrous ethanol (4.0–4.9% vol/vol of water) or any blend of these fuels. Dynamometer tests were conducted on a 1.4L, Flex-Fuel Otto engine. Gasoline with 25% vol/vol of anhydrous ethanol was blended with different ratios of hydrous ethanol. A programmable engine control unit was used to manage engine operation and spark timing calibration for maximum break torque at different speeds and torques. Combustion characteristics, such as mass fraction burned, heat release rate and combustion duration were calculated based on in-cylinder pressure curve data, measured by a special data acquisition system. Emissions of THC, NO X , CO, CO2, unburned ethanol and aldehydes were measured by a Fourier transform infrared analyzer. Hydrous ethanol addition reduced CO and THC, but increased CO2, aldehydes and unburned ethanol emissions. NO X results presented complex trends with ethanol addition, depending on the operating condition, spark advance timing and other parameters. [Copyright &y& Elsevier]

Abstract: The impact of ceasing biannual burning on the composition and the amount of soil organic matter (SOM) in grassland soils from Southern Brazil was studied by means of solid-state 13C and 15N NMR spectroscopy using soil duplicates of fields without 1, 2, 5 and 22years of burning. The examination of the duplicates demonstrated good reproducibility. Demineralization of the soil with hydrofluoric acid (HF) indicated that the fire frequency had no impact on the amount of HF-extractable SOM. Exclusion of fire resulted in a considerable decrease of the organic C stocks, whereas N and S stocks were only slightly affected. The content of pyrogenic organic C (PyOC) in the soils was determined via a combination of chemical oxidation with acid dichromate and solid-state 13C NMR spectroscopy of the oxidation resistant fraction. This analysis revealed that this decline was caused by the reduced input of decaying plant roots remaining in the soil after combustion of the aboveground vegetation during a fire. In spite of frequent burning for centuries, the PyOC concentrations were unexpectedly low in the top 5cm of the studied soils but increased clearly with soil depth, indicating that some charcoal constituents can be translocated with the soil solution. With respect to the stability of charcoal in the grassland soils, our study revealed that comparable to SOM, pyrogenic organic matter (PyOM) is composed of fractions with different stability against microbial degradation. Whereas the labile PyOM fraction showed C losses similar to that of O-alkyl C, the more stable PyOM was selectively preserved together with an alkyl C fraction. Based on the results of the present study, one can conclude that frequent burning of grassland can lead to an increased C-sequestration potential of a soil. Because the input of the additional C is mainly caused by a higher biomass production after the fire, the additional SOM contributes to the labile pool with short turn-over times rather than to the recalcitrant carbon fraction. After ceasing burning, the reduced litter input cannot compensate the fast consumption of this pool and a quick decrease of the C stocks is expected. [Copyright &y& Elsevier]

The concentration of PAHs in particulate matter was investigated in the city of Curitiba, located in south of Brazil. Urban atmospheric particulate matter was collected at six sampling sites whose characteristics were representative of the prevailing conditions. The concentration of particulate matter varied from 11.02 to 177.27 ng/m3. Particulate matter was basically composed of PAHs with 3 and 4 aromatic rings and it agrees with results of air quality monitoring performed in other cities around the world. Molecular ratios, such as (Benzo(ghi)Perilene/Indene(cd)Pyrene, B(ghi)P/I(cd)P, indicate that the source of PAHs is gasoline engines in the downtown area and diesel engines in surrounding sites representing a heavy traffic situation. It was also investigated the toxic level of particulate matter using the BaP equivalency factor. The BaPeq for all samples was between 0.42 to 1.12 ng/m3. The equivalency BaPeq indicated low health risk associated with exposure to the total PAHs content in environmental air. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the carbon dioxide (CO2) emissions from coal combustion in Brazil. A methodology using the emission factors estimated specifically for Brazilian coals is proposed. The use of secondary fuels and the electricity produced by the power plants were also considered in the calculations. The results obtained indicated carbon emissions of 1,794 Gg year-1 for 2002. In some cases 20% lower emissions were observed in comparison to the official methodology (MCT) that does not consider coal moisture and uses generic emission coefficients not adapted for Brazilian coal. The results suggest that national inventories must be revised and combustion systems should be updated in order to increase effi ciency and to reduce CO2 emissions as a sustainable measure for the coal use in the country. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the reactivity in carbon dioxide and the combustion behaviour of Brazilian coal (BC), imported coal (ICB), and charcoal (CC) in Brazil steel industry's pulverized coal injection (PCI) technology for blast furnaces (BF). It states that thermogravimetric analysis (TGA) was used to study the reactivity of the materials. Results showed that BC and CC blend have less ash content, high reactivity, and higher conversion degree compared to BC-ICB blend.

Abstract: Millions of people worldwide are affected by anthropogenic air pollution derived from the combustion of fossil fuels. In this work, we tested the effects of fetal, lactation and post-weaning ambient air pollution exposure on total homocysteine (tHcy) concentrations and on a downstream pathway element, the plasma cysteine (Cys) concentration. Two similar exposure chambers (polluted and filtered chamber) were located near an area with heavy traffic in São Paulo, Brazil, and male Swiss mice were housed there from the pre-natal period until 3 months of age. Groups during fetal, lactation and adult periods of exposure were apportioned, and tHcy and Cys plasma concentrations were assessed when the animals were 3 months old. In our study, both the tHcy and Cys concentrations were decreased in groups that spent their final stage of life in polluted chambers, suggesting recent alterations in tHcy and Cys concentrations due to air pollution exposure. The possible relationship of these data with cardiovascular dysfunction is still a matter of controversy in animals; nevertheless, epigenetic mechanisms emerge as a possible issue to consider in the investigation of the link between air pollution and Hcy measurement. [Copyright &y& Elsevier]

Abstract: The use of water wasted in hydroelectric plants as normalization dam excess, which constitute a hydrodynamic potential useful to generate electric energy which can be subsequently used to produce hydrogen and its subsequent consumption in fuel cells, has been considered as an alternative for hydraulic energy-rich countries like Brazil. The case is examined in which all the water wasted in the hydroelectric plants, spilled by dam gates to maintain acceptable water levels, from the 101 largest Brazilian hydroelectric plants was used to produce hydrogen. During the year of 2008, the electric energy produced from this utilisation would have been equivalent to 106.2TWh, an amount that corresponds to an increase of ca. 30% of the total electric energy produced in the country. Furthermore, if this amount of hydrogen was used in the replacement of internal combustion vehicles by fuel cells, this would have prevented the production of 2,000,000tons of CO2 emissions per day. The economic balance (cost of electricity produced using the wasted water minus cost of gasoline consumed) indicates a savings of ca. 200million US$. This plan would also significantly decrease production and release of greenhouse gases. [Copyright &y& Elsevier]

Abstract: The use of biodiesel is increasing as an attractive fuel due to the depleting fossil fuel resources and environmental degradation. This paper presents results of an investigation on the potentials of biodiesel as an alternative fuel and main substitute of diesel oil, comparing the CO2 emissions of the main fuels in the Brazilian market with those of biodiesel, in pure form or blended in different proportions with diesel oil (2%, 5%, and 20%, called B2, B5, and B20, respectively). The results of the study are shown in ton CO2 per m3 and ton CO2 per year of fuel. The fuels were analyzed considering their chemical composition, stoichiometric combustion parameters and mean consumption for a single vehicle. The fuels studied were: gasoline, diesel oil, anhydrous ethyl alcohol (anhydrous ethanol), and biodiesel from used frying oil and from soybean oil. For the case of biodiesel, its complete life cycle and the closed carbon cycle (photosynthesis) were considered. With data provided by the Brazilian Association of Automotive Vehicle Manufacturers (ANFAVEA) for the number of vehicles produced in Brazil, the emissions of CO2 for the national fleet in 2007 were obtained per type of fuel. With data provided by the Brazilian Department of Transit (DENATRAN) concerning the number of diesel vehicles in the last five years in Brazil, the total CO2 emissions and the percentage that they would decrease in the case of use of pure biodiesel, B100, or several mixtures, B2, B5 and B20, were calculated. Estimates of CO2 emissions for a future scenario considering the mixtures B5 and B20 are also included in this article. [Copyright &y& Elsevier]

This study was carried out to correlate total nitrogen analyzed by two different methods: Kjeldahl (wet oxidation) and Perkin‐Elmer 2.400 Series II–CHN Mode (dry oxidation or combustion) in Histosols and soil surface horizons with high organic matter content, sampled in different regions of Brazil. A positive correlation (r=0.95**) was verified between the methods, showing that Kjeldahl, because of its simplicity, can be used to routinely determine total nitrogen content in the evaluated soils. [ABSTRACT FROM AUTHOR]

Biomass burning is an important primary and secondary source of aerosol particles. The presence of carbonaceous particles in the respirable size range makes the study of this fraction important in view of possible health and climatic effects. The annual burning of sugar cane plantations causes emission of huge amounts of pyrogenic particles. Aerosol samples were collected in Araraquara city, São Paulo state, Brazil, during the harvest season for fine and coarse particles and bulk; they were analysed by electron-probe microanalysis, including facilities for low-Z element determination (low-Z EPMA) and by energy-dispersive X-ray fluorescence (EDXRF), in order to investigate the elemental composition of individual particles and bulk samples, respectively. Numerical analysis of the EPMA results by hierarchical clustering shows high contributions of carbonaceous particles that can be distinguished mainly in two different types: biogenic and carbon-rich. Additionally, two significant contributions of aluminosilicate particles were identified: as rather pure aluminosilicates or mixed with carbonaceous species. The EDXRF results are compatible with those of aerosol particles in Amazon, which is nowadays one of the main sources of biogenic particles in the world. [ABSTRACT FROM AUTHOR]

The Amazon coastal zone has become contaminated with organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs). However, information about their distribution and sources in this area is scarce, despite increasing deforestation and oil exploitation. Therefore, individual PAHs were analysed in the sediments of the Oyapock estuary, which is located in the Amazon coastal zone. This study provides information about the spatial and short-term temporal distributions of PAHs and discusses the major sources of PAHs to better understand the anthropogenic processes occurring in adjacent areas. The concentrations of all sixteen priority PAHs defined by the US EPA (United States Environmental Protection Agency, ∑ 16 PAHs) ranged from 10.9 to 138.8 ng g−1 with a mean and standard deviation = 37.9 ± 20.5 and indicated that this estuary is not contaminated, while the mean levels were similar to those found in other Amazon regions and pristine areas along the coast of Brazil. No significant differences were found in the sedimentary PAHs levels between the wet and dry sampling campaigns, despite the different climatic conditions. Diagnostic ratios, positive matrix factorization (PMF) and cluster analysis have shown that the majority of the investigated PAHs were derived from combustion processes (at least 55.1%, as estimated by the PMF model). Localized source inputs from oil and its by-products concomitantly with natural/biogenic sources appear to be secondary sources. The PAH contribution from biomass and wood combustion was approximately 13.6% and was relatively lower than other regions of the Amazon that are undergoing massive biomass burning. As the first study of PAHs in this region, this study provides vital information on the healthy state of the estuary and can serve as a baseline for assessing the impacts of acute oil disasters or the chronic input of PAHs as a result of human settlements. Image 1 • The Oyapock estuary is not contaminated with polycyclic aromatic hydrocarbons (PAHs). • PAHs showed no significant differences between the wet and dry seasons. • The highest PAH levels were detected in the sector farthest from the open ocean. • Local sources of PAHs were more important than burning biomass from distant sources. [ABSTRACT FROM AUTHOR]

Abstract: The investigation presented here was conducted during a wider experiment on the technical feasibility and environmental impacts of tire combustion in a Brazilian coal-fired power station. Nanometric-sized crystalline phases in fly ash were characterised using energy-dispersive X-ray spectrometer (EDS) and high-resolution transmission electron microscopy (HR-TEM) images. The nanoparticles, which register abundance peaks at 10 nm and 100 nm, include iron-rich oxide (e.g. hematite), Fe-sulphate (e.g., yavapaiite: KFe(SO4)2), and Fe-aluminumsilicate glass. Individual metalliferous nanoparticles have a heterogeneous microstructure in which elements such as iron, aluminum and silicon are not uniformly distributed. HR-TEM offers a powerful analytical technique in the study of fly ash nanoparticles, providing a better understanding of the detailed chemistry of this potentially strongly bioreactive component of atmospheric particulate matter. [Copyright &y& Elsevier]

Brazil has problems with the incorrect disposal of biomedical waste (BW) and studies of new technologies to eliminate this problem is becoming increasingly important. The plasma gasification technology provides reliable destruction of polluting materials, produces an inert slag and syngas. The slag can be used in civil construction, whereas syngas can be burned in the internal combustion engine (ICE) for electricity and heat generation. To collaborate with the insertion of plasma gasification technology in the Brazilian scenario, thermodynamic and economic studies of the use of BW plasma gasification are developed in this work and applied to conditions of Guaratinguetá city, São Paulo state, Brazil. Initially, the thermodynamic analysis was performed to determine the energetic efficiency of the plasma gasification system coupled with the ICE and the electricity generation potential was determinate. Economic studies were conducted to determine syngas and electricity production cost, the payback period and expected annual saving of the system. Thermodynamic analysis showed that the energy efficiency of the plasma gasifier is 78.58% and that there is a potential to produce 31% of the electricity required in the BW plasma gasification system. Through economic analysis the payback obtained was 6 years. • The plasma gasification is a good alternative for processing biomedical waste. • The syngas produced has a medium potential for electricity generation. • In the best scenario, the payback is 6 years, although the technology is expensive. • The case study found that the higher the volume of biomedical waste processed better economic return. [ABSTRACT FROM AUTHOR]

Two different types of typical Brazilian forest biomass were burned in the laboratory in order to compare their combustion characteristics and pollutant emissions. Approximately 2 kg of Amazon biomass (hardwood) and 2 kg of Araucaria biomass (softwood) were burned. Gaseous emissions of CO2, CO, and NOx and particulate matter smaller than 2.5 μm (PM2.5) were evaluated in the flaming and smoldering combustion phases. Temperature, burn rate, modified combustion efficiency, emissions factor, and particle diameter and concentration were studied. A continuous analyzer was used to quantify gas concentrations. A DataRam4 and a Cascade Impactor were used to sample PM2.5. Araucaria biomass (softwood) had a lignin content of 34.9%, higher than the 23.3% of the Amazon biomass (hardwood). CO2 and CO emissions factors seem to be influenced by lignin content. Maximum concentrations of CO2, NOx and PM2.5 were observed in the flaming phase., (Copyright © 2014 Elsevier Ltd. All rights reserved.)