Efeito das frações de asfaltenos na estabilização de emulsões de petróleo

Orientador : Prof. Dr. Carlos Itsuo YamamotoCoorientador : Profª. Drª. Agnes de Paula ScheerDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Química. Defesa: Curitiba, 23/02/2016Inclui referências : f.81-87Resumo: Na indústria petrolífera, as emulsões A/O podem ser encontradas em quase todos os processos de produção e recuperação de petróleo. Estas emulsões aumentam muito a viscosidade do petróleo afetando as operações de escoamento, produção e transporte. A maioria das emulsões de petróleo são dinâmicas, transitórias e termodinamicamente instáveis; no entanto a presença de um filme formado por agentes emulsificantes ao redor das gotas dispersas introduz uma barreira que impede o contato entre as gotas, a coalescência e portanto, aumenta a estabilidade. Os asfaltenos são os compostos mais pesados e polares do petróleo e devido ao seu carácter anfifílico são os emulsificantes naturais que mais se destacam. Sendo os asfaltenos moléculas grandes e complexas, existe a possibilidade de estuda-las de forma mais precisa sub-fracionando-as. O objetivo deste trabalho foi avaliar o comportamento de diferentes frações de asfaltenos na estabilidade de emulsões de petróleo. Para tanto, a partir de uma amostra de resíduo de vácuo, obteve-se uma fração e duas subfrações de asfaltenos por precipitação com n-heptano em diferentes proporções. Foram utilizadas as proporções de n-heptano/RV de 40:1 obtendo-se a fração total AH e um fracionamento sucessivo com as proporções 4:1 e 10:1, obtendo-se as subfrações A4 e A10, respectivamente. Estas frações foram caracterizadas por espectroscopia na região do infravermelho (FTIR), espectrometria de massas (FT-ICR MS), espectroscopia de na região do ultravioleta visível e ressonância magnética nuclear de prótons (RMN 1H). As análises mostraram que a subfração A4 apresentou maior polaridade e maior massa molar média. Um comportamento inverso foi observado quanto a aromaticidade e solubilidade, sendo a fração AH e subfração A10 as mais aromáticas e as mais solúveis. A partir das frações obtidas formulou-se emulsões modelo com heptol e avaliou-se a relação de cada fração com a estabilidade das emulsões por meio do Bottle Test e medidas da distribuição do tamanho de gotas. Os resultados apresentaram que todas as frações promoveram estabilidade nas emulsões. Após aplicação de força centrífuga, formaram-se emulsões densas contendo teores de água acima de 85% que permaneceram estáveis por mais de duas semanas. O tamanho médio de gotas obtido através da distribuição do tamanho de gotas de água nas dispersões de asfaltenos foram muito similares, bem como os resultados da separação gravitacional, sugerindo que não somente os asfaltenos mas que diferentes subfrações dessa molécula são capazes de estabilizar emulsões. Palavras chaves: Asfaltenos, precipitação, asfaltenos subfrações, emulsões.Abstract: In the crude oil industry, water-in-oil emulsions can be found in almost all processes of production and oil recovery. These emulsions increase the viscosity of the crude oil, and affect the flow operations, production and transportation. Most of the waterin- oil emulsions are dynamic, transitional and thermodynamically unstable. Only with the presence of an emulsifier film is introduced a barrier that prevents contact between the droplets, their coalescing and thus its stability. The asphaltenes are the most polar and heavier fraction in the crude oil, due their amphiphilic character, the asphaltenes are natural emulsifiers that stand out. As the asphaltenes large and complex molecules, it's possible to study them more accurately sub fracturing them. The objective of this study was to evaluate the behavior of different fractions of asphaltenes in the stability of water-in-oil emulsions. Therefore, one fraction and two differents subfractions were obtained by precipitation with n-heptane in differents ratios from a vacuum residue. The n-heptane/RV ratios were 40:1 and a successive fractionating ratio were 4:1 and 10:1, obtained the AH fractions and A4 and A10 subfractions, respectively. These fractions were characterized by Fourier Transform infrared (FTIR), mass spectroscopy (FT-ICR MS), ultraviolet-visible (UV-Vis) and Magnetic Ressonance (NMR). These measurements showed that the 4:1 fraction exhibited more heteroatomics components, more polarity and high molecular mass. An inverse correlation was observed with respect to aromaticity and solubility, the fraction AH and fraction A10 were more aromatic than the A4 fraction. From the fractions and subfractions, was formulated heptol models emulsions and evaluated the relationship of each fraction with the stability of the emulsions using the Bottle Test and measurement of droplet size distribution. The results showed that all fractions promoted a great stability in the emulsions. After application of centrifugal forces, formed a dense packed layer emulsion consists of approximately 85% water, which remained stable for more than two weeks. The average droplet size obtained through size distribution of water droplets in the asphaltene dispersions were very similar, also the results of gravitational separation, suggesting that not only the asphaltenes but different subfractions of this molecule are responsible for emulsion stabilization. Keywords: Asphaltenes, precipitation, asphaltenes subfractions, emulsio

Avaliação do material particulado fino proveniente de regiões caracterizadas com atividades de mineração

Orientador: Prof. Dr. Carlos Itsuo YamamotoCoorientador: Prof. Dr. Ricardo H. M. GodoiTese (doutorado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Química. Defesa : Curitiba, 04/08/2023Inclui referênciasResumo: A mineração de rochas calcárias é um setor básico na economia e essencial para o desenvolvimento da sociedade moderna. No entanto, a poluição atmosférica associada a este setor, está presente desde a extração até as etapas de beneficiamento das rochas. Um dos principais poluentes na produção de cal e cimento é o material particulado (MP). A exposição à fração das partículas inaláveis finas (MP2 ,5 ), pode levar a efeitos adversos à saúde e gerar impactos econômicos. Dessa forma, visando avaliar a influência das atividades de produção de cal e cimento nas emissões de MP25, realizou-se o monitoramento desse poluente presente na atmosfera das cidades de Colombo e Rio Branco do Sul, duas regiões com intensa atividade de extração e beneficiamento de rochas calcárias. Foram realizadas amostragens com dois equipamentos; o impactador Harvard, que coleta o MP25 em filtros, possibilitando a análise elementar do poluente, e sensores automáticos, que fornecem medidas de concentração mássica com alta resolução temporal. Os resultados mostraram que os elementos mais abundantes em ambos locais foram carbono negro, Ca, S e K. A correlação entre esses elementos foi associada à atividade de beneficiamento de rochas calcárias em fornos a altas temperaturas. Traço dos elementos Ni, Cr, Cu, Pb, Zn e Mn foram encontrados enriquecidos em ambos os pontos amostrais, no entanto, não houve correlação entre esses elementos contaminantes e a fabricação de cal ou de cimento. Os riscos à saúde associados à inalação de Pb, Zn, Cu, Cr (VI), Ni e Mn foram calculados, e, em ambas as cidades, não houveram riscos cancerígenos e não cancerígenos nas concentrações encontradas. Especificamente para Colombo, a aplicação da Análise dos Componentes Principais Absoluta (APCA), revelou que a combustão nas indústrias de cal são as fontes majoritárias de MP2,5 (30 %), e, possivelmente contribuem para emissões fugitivas (15 %). Utilizando o cálculo de risco relativo e as concentrações de MP2,5 obtidas com os sensores automáticos, verificou-se que, as concentrações médias anuais acima dos limites estabelecidos pela OMS foram responsáveis por 2,0 % e 3,5 % das mortes prematuras por causas naturais nas cidades de Colombo (2021) e Rio Branco do Sul (2021 e 2022), respectivamente. A partir destas estimativas, aplicou-se o método Disability-Adjusted Life Years (DALY) e foram calculados os custos associados a essa mortalidade, estratificado por sexo e faixa etária. O ônus da poluição por MP2,5 foi estimado em R$19,7 milhões (2021), para a cidade de Colombo e R$ 7,2 milhões para a cidade de Rio Branco do Sul (2021 e 2022). Observou-se que os homens na faixa etária entre 40-69 anos foram os mais susceptíveis à poluição. O controle operacional nos processos de calcinação, redução do consumo de combustível e matéria-prima, uso de equipamentos de controle de MP e de gases precursores, são medidas desejáveis para redução dos níveis de MP2,5 nas áreas de estudo. Evidencia-se neste trabalho, que o investimento em tecnologias de controle e monitoramento de emissões, são mais rentáveis do que se pagar pelos danos causados pela poluição posteriormente.Abstract: Limestone mining is a basic economic sector and essential for the development of modern society. However, atmospheric pollution related to activities in this sector is present throughout all stages of the mining project, from rock extraction to processing stages. One of the main impacts of lime and cement production is the emission of particulate matter. Exposure to the fine fraction of this pollutant, both mass concentration and chemical composition, can lead to adverse health effects and economic impacts. In order to assess the influence of lime and cement production activities on PM25 emissions and the impacts generated on the population's health, monitoring of fine particles was carried out in Colombo and Rio Branco do Sul cities, two regions of intense activity extraction and processing of limestone rocks. Samplings were carried out with two different equipment, the Harvard impactor, which collects the PM25 in filters, allowing the elemental analysis of the pollutant, and low-cost sensors, which provide measurements with high temporal resolution. The results showed that the most abundant elements in both locations were BC and the enriched metals Ca, S and K. The correlation between these elements was associated with the activity of processing limestone rocks in kilns at high temperatures. Trace of heave metals, like Ni, Cr, Cu, Pb, Zn, Br and Mn were found enriched in both sample regions, however, there was no correlation between these elements and the manufacture of lime or cement. The health risks assessment associated of inhalation of Pb, Zn, Cu, Cr(VI), Ni and Mn were verified. The results showed that non-carcinogenic risk and carcinogenic risk were no significant for local residents during the evaluation period, in the two cities. Specifically, in Colombo city, the application of absolute principal component analysis revealed that combustion in lime manufacturing are the major sources of PM25 (30 %), these industries also emitted significantly to the fugitive dust, the second largest source of PM25 (15 %). Using the relative risk methodology and PM2.5 concentrations measurement with low-cost sensors, it was found that average concentrations above WHO limits accounts for 2.0 % and 3.5 % of premature deaths due to natural causes in Colombo (2021) and Rio Branco do Sul (2021 and 2022), respectively. Based on these estimates, the DALY (Disability Adjusted Life Years) methodology was applied and the costs associated with this mortality were calculated, the results were stratified by gender and age group. The costs of premature deaths resulted in R$19.7 million, in 2021, for the Colombo city and R$ 7.2 million for the Rio Branco do Sul city, in 2021 and 2022. In addition, were observed that the 40-69 age group were the more susceptible to PM pollution. Operational control in calcination processes to reduce fuel and raw material consumption, use of particulate emission control equipment, technology and control of precursor gases are strategies that can considerably reduce PM25 levels in the study areas. It's clear that investing in emission control and monitoring technologies can be more profitable than to pay for the damage of air pollution later

Impact assessment of IMO’s sulfur content limits: a case study at latin America’s largest grain port

The world ocean fleet consumes around 4.3 million barrels of heavy fuel oil (HFO) daily, releasing large amounts of sulfur-enriched gaseous and particulate pollutants into the atmosphere. The International Maritime Organization (IMO) has set new sulfur content limit values for HFO under the Global Sulfur Cap 2020 (GSC-2020) program to reduce its environmental and public health impact. This study assesses the environmental benefits of the sulfur content limit values for heavy fuel oil set by the IMO on sulfur emissions, trace element concentrations, and ship related PM2.5 pollution at Paranaguá, the largest grain port in Latin America. X-ray Fluorescence analysis revealed that the concentrations of vanadium (V) and nickel (Ni) in PM2.5 (i.e., finer particulate matter), which are prevalent trace elements in ship exhaust emissions, decreased significantly from 25.4 ng m− 3 and 5.8 ng m− 3 in 2019 to 3.5 ng m− 3 and 2.2 ng m− 3 in 2020, respectively. The V/Ni ratio also changed from 4.3 in 2019 to 1.8 in 2020, suggesting significant changes in the signature of marine vessel emission. Sulfur emissions also decreased, with average concentrations of 2.0 µg m− 3 in 2019 and 1.2 µg m− 3 in 2020. The primary PM2.5 concentration, attributed to ship emissions using V as a tracer, was reduced from ~ 80% in 2019 (mean = 35.8%) to less than 5% (mean = 4.9%) in 2020. Inhalation exposure to V and Ni in PM2.5 showed a decrease in the hazard quotient (HQ) and hazard index (HI) in 2020 compared to 2019, indicating potential health benefits. Our findings underscore the need for more robust international shipping policies prioritizing health objectives and reducing greenhouse gas emissions concurrently. Despite the significant health benefits associated with the implementation of low-sulfur fuels in global shipping, there remains a need for further investigation into the long-term effects of these fuels on air quality and human health

A new strategy for risk assessment of PM2.5-bound elements by considering the influence of wind regimes

For regulatory purposes, air pollution has been reduced to management of air quality control regions (AQCR), by inventorying pollution sources and identifying the receptors significantly affected. However, beyond being source-dependent, particulate matter can be physically and chemically altered by factors and elements of climate during transport, as they act as local environmental constraints, indirectly modulating the adverse effects of particles on the environment and human health. This case study, at an industrial site in a Brazilian coastal city – Joinville, combines different methodologies to integrate atmospheric dynamics in a strategic risk assessment approach whereby the influence of different wind regimes on environmental and health risks of exposure to PM2.5-bound elements, are analysed. Although Joinville AQCR has been prone to stagnation/recirculation events, distinctly different horizontal wind circulation patterns indicate two airsheds within the region. The two sampling sites mirrored these two conditions and as a result we report different PM2.5 mass concentrations, chemical profiles, geo-accumulation, and ecological and human health risks. In addition, feedback mechanisms between the airsheds seem to aggravate the air quality and its effects even under good ventilation conditions. Recognizably, the risks associated with Co, Pb, Cu, Ni, Mn, and Zn loadings were extremely high for the environment as well as being the main contributors to elevated non-carcinogenic risks. Meanwhile, higher carcinogenic risks occurred during stagnation/recirculation conditions, with Cr as the major threat. These results highlight the importance of integrating local airshed characteristics into the risk assessment of PM2.5-bound elements since they can aggravate air pollution leading to different risks at a granular scale. This new approach to risk assessment can be employed in any city's longer-term development plan since it provides public authorities with a strategic perspective on incorporating environmental constraints into urban growth planning and development zoning regulations