IZABEL DA SILVA ANDRADE
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Resumo IPEN-doc 28971 Methane determination in São Paulo coastal regions using the Cavity Ring-Down Spectroscopy (CRDS) technique2021 - CORREA, THAIS; MACEDO, FERNANDA M.; ARAUJO, ELAINE C.; ANDRADE, IZABEL S.; GOMES, ANTONIO A.; SILVA, JONATAN; LANDULFO, EDUARDOMethane is one of the main greenhouse gases due to its high radiation absorption capacity. The increase in methane emissions from anthropogenic sources causes concern in the entire scientific community due to the aggregated uncertainties, generating several works focused on the identification and quantification of generating sources. This work aims to quantify methane in two distinct regions, the first study region is in Cubatão city, located in the São Paulo coast. It is an important petrochemical complex with high industrial activities and environmental impact, presenting 25 large companies in the chemical sector, distributed in an area of 143 Km2. Another region observed is Intanhaém, on the coast of the state of São Paulo. This region doesn´t present industrial activity and has a low population index. The technique used to detect methane in the atmosphere was Cavity ring-down spectroscopy (CRDS), which consists on analysis of atmospheric components, in a small cavity that has a laser and high reflectivity mirrors of 99.999%, allowing the signal travel for kilometers inside the cavity, in a short time, increasing the sensitivity of detection of compounds in the sample.Artigo IPEN-doc 26790 Correlation between two different real time data acquisition systems2019 - MACEDO, FERNANDA M.; CORREA, THAIS; ARAUJO, ELAINE; ANDRADE, IZABEL; ARLEQUES, ANTONIO G.; MIRANDA, JULIANA T. de M.; SILVA, JONATAN da; GUARDANI, ROBERTO; VESELOVSKII, IGOR; LANDULFO, EDUARDOFugitive emissions, defined as unintended or irregular leaks of gases and vapors, these are an important source of pollutants to the atmosphere, which is difficult to monitor and control. These sources are present in different sites, including megacities like São Paulo that are growing in size and economic activity. At the same time, there is a remarkable growth in concerns about the environmental issues associated with these activities. In a constantly changing world, with increasing concentrations of greenhouse gases (GHGs), among them methane (CH4) and volatile organic compounds (VOC), mitigation of atmospheric emission of these gases to contain global warming, make field campaigns in the metropolitan region of São Paulo very relevant. Optical remote sensing techniques as lidar can attend the need for real time and trustable information on fugitive emissions. The Cavity Ringdown Laser Spectroscopy (CRDS) technique was adopted because it is widely used in the detection of gas samples that absorb light at specific wavelengths and also for their ability to detect mole fractions up to the parts per trillion level. The Raman lidar system used includes a commercial laser pulsed Nd:YAG Quantel S.A., model CFR 200, with wavelengths of 355 nm, 353 nm and 396 nm, 120 mJ pulse power, with laser repetition rate of 20 Hz and pulse width of 20 s, with a spatial resolution of 7,5 m. The system includes an ethernet interface, used together with LabView software to control the measurement and readout of the acquired data. The mixing ratio of CH4 can be observed within the planetary boundary layer. The measured methane profiles correlate with the acquisitions made with the CRDS, however, an additional contribution of control data in which the Raman lines detect with high sensitivity.Resumo IPEN-doc 26696 Implementation of CH4 (methane) Raman lidar detection system from anthropic sources2019 - LANDULFO, EDUARDO; MACEDO, FERNANDA M.; CORREA, THAIS; ARAUJO, ELAINE; ANDRADE, IZABEL; ARLEQUES, ANTONIO G.; MIRANDA, JULIANA T. de M.; SILVA, JONATAN da; GUARDANI, ROBERTOFugitive emissions, defined as unintended or irregular leaks of gases and vapors, are an important source of air pollution that is difficult to monitor and control. Within industrial facilities such as oil and gas processing plants, fugitive methane emissions can be a significant source of greenhouse gas emissions. In Brazil, as in other countries, there are specific regions with high concentration of industrial activities, and showing high population density. These sites, including megacities like São Paulo, are growing in size and economic activity. At the same time, there is a remarkable growth in concerns about the environmental issues associated with these activities. In a constantly changing world, with increasing concentrations of greenhouse gases (GHGs), among them methane (CH4) and volatile organic compounds (VOC), mitigation of atmospheric emission these gases to contain global warming, is of key concern, gas data suggest that fugitive emissions accounted for more than 5% of global greenhouse gas emissions over the past 5 years. Optical remote sensing techniques as lidar can attend the need for real time and trustable information on fugitive emissions. These techniques are non-intrusive, of relative simple construction, thus demanding less maintenance, and are able to provide data from distant locations with a high spatial resolution, typically up to 20 km from the measuring local, and 3 to 4 m long segments. Besides, information on different pollutants can be obtained simultaneously by adequate optical arrangements and data treatment methods. The technique can supply adequate information at lower costs and less effort than other techniques. The Cavity Ringdown Laser Spectroscopy (CRDS) technique was adopted because it is widely used in the detection of gas samples that absorb light at specific wavelengths and also for their ability to detect mole fractions up to the parts per trillion level. The correlation of the data between the techniques of real-time detection becomes interesting, since practical operations, fast and with a high level of sensitivity and precision are made. The mixing ratio of CH4 can be observed within the planetary boundary layer. The measured methane profiles correlate with the acquisitions made with the CRDS, however, an additional contribution of control data in which the Raman lines detect with high sensitivity.