Empirical and chemical equilibrium modelling for prediction of biomass gasification products in bubbling fluidized beds

In this work, two approaches to predict the producer gas composition obtained by direct (air) biomass gasification in bubbling fluidized beds were developed and compared, namely empirical modelling based on reported experimental results in the literature and non-stoichiometric chemical equilibrium modelling. For this purpose, an extensive database containing a set of 19 published experimental results from the literature was compiled and a non-stoichiometric chemical equilibrium model developed. The prediction capability of the empirical and chemical equilibrium model was evaluated by comparison with experimental data obtained in an 80 kWth bubbling fluidized bed direct (air) biomass gasifier. The empirical model shows moderate accuracy in the determination of the producer gas composition (CO, H2 and CH4), whereas the chemical equilibrium clearly overestimates the concentration of H2 and CO, and underestimates the concentration of CH4, leading to subpar accuracy in the determination of typical gasification efficiency parameters. Thus, the empirical model is suited for preliminary estimates of gasification products, while black-box chemical equilibrium modelling, without experimental knowledge integration, is considered as unreliable for these gasification conditions.publishe

Critical aspects of biomass ashes utilization in soils: composition, leachability, PAH and PCDD/F

Bottom and fly ashes streams collected along a year in several biomass thermal plants were studied. The bulk composition of ashes and other chemical characteristics that may impact soil application showed a high variability depending on the ash stream, combustion technology and ash management practice at the power plants. The acid neutralization capacity (ANC) and metal’s availability for leaching at fixed pH 7 and 4 was performed according with EA NEN 7371, as a quick evaluation method to provide information on the long-term behavior of ashes, regarding heavy metals and also plant nutrients release. Also the pH dependence leachability study was performed according to CEN/TS 14429 for predicting the leaching behavior under different scenarios. Leachability profiles were established between pH 3 and 12, allowing to distinguish different solubility control phenomena of toxic heavy metals (Cu, Cr, Mn, Ni, Zn, Pb) as well as other salts (Ca, K, Mg, Na, Cl). The ANC of fly ashes at pH 4 (3.6–9.6 molH+/kg) were higher than that observed for the bottom ashes (1.2–2.1 molH+/kg). Ashes were also characterized for persistent organic pollutants (POP), such as polycyclic aromatic hydrocarbons (PAH) and paradibenzodioxines and furanes (PCDD/F). Contents were found to be much higher in fly ash than in bottom ash streams. None of the PAH levels did reach the current national limit value of sewage sludge application in soils or the guide value for ash in north European countries. However, PCDD/F contents, which are not regulated, varied from non-detectable levels to high amounts, regardless the level of loss on ignition (LOI) or unburned carbon content in fly ashes. Given the current ash management practices and possible use of blends of bottom and fly ash streams as soil conditioners resembles clear the urgent need to regulate ash utilization in soils, incorporating limit values both for heavy metals, PAH and PCDD/F

9q21.13q21.31 deletion in a patient with intellectual disability severe speech delay and and dysmorphic features a newly recognized microdeletion syndrome

The increased use of chromosomal microarray analysis has led to the identification of new microdeletion/microduplication syndromes, enabling better genotype-phenotype correlations. Interstitial deletions involving the long arm of chromosome 9 are rare but recently a microdeletion syndrome at 9q21.13 was suggested, with mental retardation, speech delay, epilepsy, autistic behaviour and moderate facial dysmorphism as the main characteristics. Here we present a male child with intellectual disability, severe speech delay, microcephaly and dysmorphic features carrying an interstitial deletion, detected by the Affymetrix Cytoscan HD microarray, of 6.56 Mb at 9q21.13q21.31 region encompassing 16 OMIM genes (arr[GRCh37] 9q21.13q21.31(76551542_83116342)x1). Among the genes in the deleted region the PRUNE2, PCSK5, RORB and TRPM6 genes are expressed in the nervous system and have been describe as being candidate genes to play a role in mental retardation or neurological disorders. Although the cohort of patients identified with deletions in this region is still small our patient phenotype partially overlaps the others described in the literature. The collection of more cases with deletion of the 9q21.13 region will help establishing a clear classification for this CNV, finding the real weight in the patient’s phenotype, delineating the genetic counseling for their families, and clearly establishing this microdeletion as a syndrome.N/

Fluxos verticais de CO2 em várias fases do ciclo de crescimento de uma cultura de curta rotação de choupo no Nordeste de Portugal

As culturas energéticas lenhosas de curta rotação constituem uma oportunidade para aumentar a rentabilidade de muitos ecossistemas, principalmente nas regiões onde podem representar uma mais-valia comparativamente às culturas alimentares. Estas culturas são também consideradas um meio eficaz de mitigação do efeito estufa, devido à sua contribuição para a redução do uso de combustíveis fósseis e ao seu impacto positivo na transferência do carbono da atmosfera para o sistema solo/vegetação (Schulze et al. 2000). Com o objetivo de avaliar e otimizar a contribuição deste tipo de culturas de gestão intensiva no sequestro de carbono, procedeu-se à medição de fluxos verticais de CO2 num sistema de biomassa lenhosa para produção de energia, instalado no nordeste transmontano, em particular numa plantação de choupo híbrido

Incorporation of biomass fly ash and biological sludge in the soil: effects along the soil profile and in the leachate water

Purpose This work aimed to study the effect of the application of biomass fly ash in the soil profile and percolate water, which is a novel feature. The results produced by this work pose a useful contribute for by-products’ valorization for the pulp and paper industry, namely fly ash and sludge, diverting them from landfills and achieving significant savings. Materials and methods Soil profiles (0.60 m) were collected in the field and into laboratory-scale vessels. Four soil profiles were used in this work. One of the profiles was used as control. To each of the other three, 7.5 Mg ha−1 of biomass fly ash, fly ash combined with sludge (50:50%wt.), or a conventional liming agent (CaO) were added. A simulation of the daily natural watering of the soils has been made throughout 1 month, with collection of the daily percolating from the bottom of the vessels. After this period, soil profiles were divided into three equal-sized depth layers (0.20 m each). Soil pH, electrical conductivity, and available Ca, Mg, K, P, Na, Mn, Fe, Zn, and Cu contents were determined in the three layers for each of the four soil profiles used. A parallel experiment was conducted in which additional pots of soil were prepared with the same amendment. Ryegrass (Lolium perenne) was sown in order to evaluate the effect on biomass growth and possible phytotoxicity. Results and discussion Amendment with biomass fly ash elevated soil pH slightly, to values within the most adequate range for plant growth. Results showed small raises in the availability of the essential plant macronutrients Ca, K, and Mg, especially in the top layer of the soils, where the amendment materials were applied. The mobilization of cations to the groundwater was always minimal, which is promising since it means little contamination to the groundwater. Ash and ash + sludge amendments produced similar plant growth results when compared to the control. However, biomass grown in Cao-amended pots showed the higher root size. Conclusions Incorporation in the soil proved to be a viable way to manage fly ash and sludge from pulp and paper industry, which could mean considerable savings. The effect on soil fertilization was similar to the conventional liming agent. No obvious hazardous effect on the soil or groundwater was found.publishe

Simultaneous analysis of some club drugs in whole blood using solid phase extraction and gas chromatography–mass spectrometry

The use of psychoactive substances to improve social relations and increase body energy, in Rave Culture, has raised many legal and health public concerns, both for illicit trade and consumption. Therefore, forensic toxicology plays an important role in this area, mainly linked to the detection and quantitation of these substances, both in vivo and in post-mortem samples. In fact, at the moment, forensic sciences have been under public authorities’ scrutiny and critical look, due to the increasing attention of the media and public opinion, always applying for the use of scientific knowledge to help solving forensic cases. However, forensic toxicology results are only reliable to solve legal cases if all the analytical methodologies used are appropriately validated. In this work, a methodology for the extraction and analysis of 7-aminoflunitrazepam, buprenorphine, flunitrazepam, ketamine, methadone, phencyclidine (PCP) and d-propoxyphene was developed for whole blood samples, with Solid-Phase Extraction (SPE), using OASIS MCX SPE columns, and gas chromatography coupled to mass spectrometry. The procedure presented here proved to be reliable, specific, selective and sensitive, with good LODs and LOQs and good precision.The adoption of a SPE procedure with an automatic SPE extraction device, allowed an increased level of automation in sample treatment, being contemporarily less time-consuming, increasing productiveness, and allowing good recovery and appropriate selectivity being, also, simple and reproducible. The simultaneous detection and quantitation of all compounds by the same extraction and detection methodology is crucial and has a great potential for forensic toxicology and clinical analysis.info:eu-repo/semantics/acceptedVersio

Biomass and coal fly ash as cement replacement on mortar properties

Nowadays, construction sector tries to implement several options to solve the issues related to concrete. The main goal of this work was to study the effect of biomass fly ash, blended with coal fly ashes or alone, as cement replacement in the mortars properties. Mortars with biomass fly ashes have lower slump value than the reference. Mortars with 20% of cement substitution presents better results for all curing time. However, in the three percentages of substitution, and for all curing periods, the best results were found for mortars composed with biomass fly ashes. This work showed that is possible to use biomass fly ashes as partial cement substituent with good results in terms of durability and quality of concrete. Its utilization at an industrial level of concrete production can decrease the energy and raw materials consumption related to cement production and allows a more sustainable option on the ash management.FCT (Fundação para a Ciência e Tecnologia – Portugal) and to the Doctoral Program Eco-Construction and Rehabilitation for supporting the PhD scholarship (with the reference PD/BD/52661/2014

Atividade fotocatalítica de camadas de TiO2 otimizadas

Mestrado em Engenharia de materiaisEste trabalho avalia a capacidade fotocatalítica de camadas de TiO2 depositadas por pulverização em substratos cerâmicos. Aferiu-se a influência do tipo de corante e do pH da solução na fotodegradação de soluções coradas. Estudou-se ainda a eficiência das placas em ensaios sucessivos e a sua reprodutibilidade. A eficiência das camadas na destruição de poluentes gasosos, nomeadamente o NOX também foi avaliada. Em condições otimizadas obtém-se 50% de descoloração ao fim de 161 minutos de irradiação; a quase total descoloração (95%) é atingida após 11 horas de ensaio, à taxa de reação de 4,3x10-3 min-1, para soluções coradas com laranja II (20 mg/l). Para soluções com o corante azul de metileno (20 mg/l) obtém-se 50% de descoloração ao fim de 195 minutos de irradiação e a quase total descoloração (97%) após 11 horas à taxa de reação de 5,1x10-3 min-1. No caso do corante laranja II o desempenho é mais eficaz em pH neutro. Pelo contrário, o pH ácido é mais vantajoso no caso do corante azul de metileno. Ao final de 11 horas de tempo reação a descoloração alcançada foi de 98% à taxa 6,6x10-3min-1. As placas cerâmicas com a camada de titânia apresentaram um bom desempenho na fotodegradação de óxidos de azoto. Para uma concentração de 0,5 ppm em NOx, foi conseguida uma degradação de 78% ao final de 25 minutos, à taxa de degradação de 80,9x10-3 min-1. As peças cerâmicas com camadas ativas de titânia apresentam-se assim como um produto alternativo ao uso de óxidos em suspensão não sendo necessária a etapa, sempre morosa, de remoção dos óxidos da suspensão no final do tratamento. Apresentam-se também como um produto eficiente na descontaminação de ambientes com elevadas concentrações em óxidos de azoto. Além das propriedades fotocatalíticas as placas preparadas neste trabalho são fáceis de limpar, exibem um aspeto agradável e uma superfície resistente preenchendo, assim, os requisitos industriais e comerciais para este tipo de produtos.This study evaluates the photocatalytic efficiency of TiO2 layers deposited by jet-spraying on ceramic substrates. The influence of the dye type and solution pH on the photodegradation of colored solutions was assessed. The layers efficiency in successive trials and the tests reproducibility was also evaluated. The layer efficacy for the destruction of gaseous pollutants, such as NOX, was also studied. For optimized conditions, colored solutions with orange II dye (20 mg/l) presents a discoloration of 50% after 161 minutes of irradiation; the almost total discoloration (95%) was reached after 11 hours of exposition at a reaction rate of 4.3x10-3 min-1. Colored solutions with methylene blue dye (20 mg/l) present a discoloration of 50% after 195 minutes of irradiation and the almost total discoloration (97%) after 11 hours at a reaction rate of 5.1x10-3 min-1. For the orange II dye the best performance is observed at neutral pH. On the contrary, an acid pH is more effective for methylene blue dye. After 11 hours of exposition to radiation was achieved a discoloration of 98% at a rate of 6.6x10-3 min-1. The prepared ceramic tiles with the titania active layer presented a good performance for the photodegradation of nitrogen oxides. For a concentration of 0.5 ppm (NOx) was achieved a degradation of 78% after 25 minutes at a degradation rate of 80.9x10-3 min-1. Thus, the ceramic tiles with the active titania layer are an alternative to the use of oxides in suspension not requiring the time-consuming step of removing them in the end of the treatment. They are also efficient for the decontamination of environments with high nitrogen oxides concentration. Beside the photocatalytic properties the material prepared in this work are easy to clean, exhibit a pleasing appearance and have a durable surface, thus filling the industrial and commercial requirements for such type of products

A fast and reliable method for GHB quantitation in whole blood by GC–MS/MS (TQD) for forensic purposes

Gamma-Hydroxybutyric Acid (GHB) is an endogenous compound with a story of clinical use since the 1960’s. However, due to its secondary effects, it has become a controlled substance, entering the illicit market. A fully validated, sensitive and reproducible method for the quantification of GHB by methanolic precipitation and GC-MS/MS (TQD) in whole blood is presented. Using 100 µL of whole blood, obtained results included a LOD and LLOQ of 0.1 mg/L and a recovery of 86% in a working range between 0.1 and 100 mg/L. This method is sensitive and specific to detect the presence of GHB in small amounts of whole blood (both ante-mortem or post-mortem), and is, to the authors’ knowledge, the first GC-MS-MS TQD method that uses different precursor ions and product ions for the identification of GHB and GHB-D6 (internal standard). Hence, this method may be especially useful for the study of endogenous values in this biological sample.info:eu-repo/semantics/acceptedVersio