Biodiesel production from waste frying oils over lime catalysts

Biodiesel production from semi-refined oils (SRO) and waste frying oils (WFO) was studied using commercial CaO as heterogeneous catalyst. The methanolysis tests were carried out in mild reaction conditions (62 A degrees C, atmospheric pressure). With such conditions, SRO (soybean and rapeseed) allowed to produce a biodiesel containing 97-98 % of methyl esters (FAME), whereas WFO only provided 86-87 % of FAME. The lower FAME yield for WFO oil is ascribable to the partial neutralization of the catalyst by free fatty acids. Also, soaps formation from the WFO oil reduced the weight yield of the oil phase (containing FAME) obtained and increased the MONG content of the glycerin phase. The catalysts stability tests showed high stability even when WFO oil was processed. Catalytic tests performed with blends of WFO/semi-refined oils showed blending as a good strategy to process low value raw oils with minor decay of the catalyst performance. Both WFO and semi-refined oils showed S-shape kinetics curves thus discarding significant differences of the reaction mechanisms.

Assessment of fungal contamination in waste sorting and incineration: case study in Portugal

Organic waste is a rich substrate for microbial growth, and because of that, workers from waste industry are at higher risk of exposure to bioaerosols. This study aimed to assess fungal contamination in two plants handling solid waste management. Air samples from the two plants were collected through an impaction method. Surface samples were also collected by swabbing surfaces of the same indoor sites. All collected samples were incubated at 27◦C for 5 to 7 d. After lab processing and incubation of collected samples, quantitative and qualitative results were obtained with identification of the isolated fungal species. Air samples were also subjected to molecular methods by real-time polymerase chain reaction (RT PCR) using an impinger method to measure DNA of Aspergillus flavus complex and Stachybotrys chartarum. Assessment of particulate matter (PM) was also conducted with portable direct-reading equipment. Particles concentration measurement was performed at five different sizes (PM0.5; PM1; PM2.5; PM5; PM10). With respect to the waste sorting plant, three species more frequently isolated in air and surfaces were A. niger (73.9%; 66.1%), A. fumigatus (16%; 13.8%), and A. flavus (8.7%; 14.2%). In the incineration plant, the most prevalent species detected in air samples were Penicillium sp. (62.9%), A. fumigatus (18%), and A. flavus (6%), while the most frequently isolated in surface samples were Penicillium sp. (57.5%), A. fumigatus (22.3%) and A. niger (12.8%). Stachybotrys chartarum and other toxinogenic strains from A. flavus complex were not detected. The most common PM sizes obtained were the PM10 and PM5 (inhalable fraction). Since waste is the main internal fungal source in the analyzed settings, preventive and protective measures need to be maintained to avoid worker exposure to fungi and their metabolites.

Acompanhamento da III fase do aterro sanitário da Meia Serra

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Hidráulica

ECO-betão com adição de resíduo da indústria petrolífera

Dissertação de natureza Científica para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização em Edificações

Utilização de materiais anti-vibráteis e de isolamento acústico na via férrea

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Vias de Comunicação e Transportes

Estudo laboratorial e em condições reais sobre o aglomerado de cortiça expandida aplicado como revestimento exterior

Trabalho Final de Mestrado elaborado no Laboratório de Engenharia Civil para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações no âmbito do protocolo de cooperação entre o ISEL e o LNEC

A New Method to Determine the Density and Water Absorption of Fine Recycled Aggregates

The construction industry keeps on demanding huge quantities of natural resources, mainly minerals for mortars and concrete production. The depletion of many quarries and environmental concerns about reducing the dumping of construction and demolition waste in quarries have led to an increase in the procuring and use of recycled aggregates from this type of waste. If they are to be incorporated in concrete and mortars it is essential to know their properties to guarantee the adequate performance of the end products, in both mechanical and durability-related terms. Existing regulated tests were developed for natural aggregates, however, and several problems arise when they are applied to recycled aggregates, especially fine recycled aggregates (FRA). This paper describes the main problems encountered with these tests and proposes an alternative method to determine the density and water absorption of FRA that removes them. The use of sodium hexametaphosphate solutions in the water absorption test has proven to improve its efficiency, minimizing cohesion between particles and helping to release entrained air.

Assessment of workers’ exposure to Aflatoxin B1 in a Portuguese waste industry

Aflatoxin B1 (AFB1) is considered by different International Agencies as a genotoxic and potent hepatocarcinogen. However, despite the fact that the fungi producing this compound are detected in some work environments, AFB1 is rarely monitored in occupational settings. The aim of the present investigation was to assess exposure to AFB1 of workers from one Portuguese waste company located in the outskirt of Lisbon. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Forty-one workers from the waste company were enrolled in this study (26 from sorting; 9 from composting; 6 from incineration). A control group (n = 30) was also considered in order to know the AFB1 background levels for the Portuguese population. All the workers showed detectable levels of AFB1 with values ranging from 2.5ng ml−1 to 25.9ng ml−1 with a median value of 9.9±5.4ng ml−1. All of the controls showed values below the method’s detection limit. Results obtained showed much higher (8-fold higher) values when compared with other Portuguese settings already studied, such as poultry and swine production. Besides this mycotoxin, other mycotoxins are probably present in this occupational setting and this aspect should be taken into consideration for the risk assessment process due to possible synergistic reactions. The data obtained suggests that exposure to AFB1 occurs in a waste management setting and claims attention for the need of appliance of preventive and protective safety measures.

Occupational exposure to particulate matter in 2 Portuguese waste-sorting units

Objectives - This study intended to characterize work environment contamination by particles in 2 waste-sorting plants. Material and Methods - Particles were measured by portable direct-reading equipment. Besides mass concentration in different sizes, data related with the number of particles concentration were also obtained. Results - Both sorting units showed the same distribution concerning the 2 exposure metrics: particulate matter 5 (PM5) and particulate matter 10 (PM10) reached the highest levels and 0.3 μm was the fraction with a higher number of particles. Unit B showed higher (p < 0.05) levels for both exposure metrics. For instance, in unit B the PM10 size is 9-fold higher than in unit A. In unit A, particulate matter values obtained in pre-sorting and in the sequential sorting cabinet were higher without ventilation working. Conclusions - Workers from both waste-sorting plants are exposed to particles. Particle counting provided additional information that is of extreme value for analyzing the health effects of particles since higher values of particles concentration were obtained in the smallest fraction.

EWASTEU Programme: proposals to minimise the problem of e‑waste

Hoje em dia muitos dos equipamentos elétricos e eletrónicos que compramos ficam obsoletos num curto espaço de tempo por causa dos rápidos avanços tecnológicos neste campo. Equipamentos como computadores, telemóveis e equipamentos elétricos e eletrónicos de pequeno e grande porte são transformados em lixo eletrónico e muitos deles são despejados no lixo comum. Para alterar este cenário, a União Europeia publicou diretivas neste domínio com o intuito de controlar o crescimento do lixo eletrónico e reduzir o seu impacto. Neste contexto, a Universidade de Yaşar (Turquia) submeteu à União Europeia um projeto (EWASTEU) com o objetivo de fornecer uma visão do que está acontecer com o equipamento transformado em lixo eletrónico e de apresentar algumas propostas para minimizar este problema. Uma das principais questões a ser respondida será a adequação das diretivas europeias.

Incorporação de resíduo da indústria petrolífera em argamassas de cal hidráulica para a reabilitação de edifícios

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações

Moradia no centro histórico do Montijo: reabilitação vs construção nova

Dissertação para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações

Caracterização laboratorial de misturas betuminosas com incorporação de agregado siderúrgico inerte para construção (ASIC)

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Vias de Comunicação e Transportes

Contribuição para o estudo dos subprodutos de uma ETAR: gradados e areias

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Civil, na Área de Especialização de Hidráulica

Acompanhamento da ampliação do restaurante mexicano "La Siesta", em Algés

Relatório de Estágio para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações