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1.
Environ Sci Pollut Res Int ; 30(7): 18078-18090, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36205870

RESUMO

Tannins are polyphenols that can be extracted from different parts of the plant and have different known commercial applications. The extraction of tannins generates a significant amount of low-density wastes. An alternative that can be applied to ensure energy reuse of this low-density waste is a densification process, such as briquetting. Thus, this research work aimed to assess the energy potential of the residue from the extraction of tannins of different forest species, aiming at its energy reuse in the form of briquettes. Stem barks of 6 forest species (Acacia mangium, AM; Anacardium occidentale, AO; Anadenanthera colubrina, AC; Azadirachta indica, AI; Mimosa caesalpiniaefolia, MC; Mimosa tenuiflora, MT) were used after tannin extraction. Bulk density, energy (higher, lower, and net heating value) and thermal (TG/DTG) properties, and chemical constitution (extractives, lignin, and holocellulose) of the materials were determined. In addition, briquette compaction ratio, apparent density, volumetric expansion, and water adsorption over the days were evaluated. The highest bulk densities were found in the barks of Anadenanthera colubrina (0.529 g.cm-3) and Mimosa tenuiflora (0.407 g.cm-3), whereas the species that showed the best result of higher heating value was Acacia mangium (20.44 MJ.kg-1), followed by Azadirachta indica (19.39 MJ.kg-1) and Mimosa caesalpiniifolia (18.85 MJ.kg-1). Briquetting increased the density of the evaluated material by 2.3 to 4.9 times. All briquettes produced with wastes from tannin extraction evaluated in this work showed potential for energy production. With more information on the quantification of waste generated and data on the economic viability of production, these tannin-producing industries can benefit both environmentally and economically, by reusing these wastes for energy production.


Assuntos
Acacia , Fabaceae , Gerenciamento de Resíduos , Taninos/química , Lignina
2.
Environ Sci Pollut Res Int ; 27(34): 43403-43411, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33011942

RESUMO

The pulp bleaching process removes or transforms the chromophore groups in the pulp, so that the final product reaches a desired brightness. However, this chemical treatment inevitably results in yield loss. Therefore, the objective of this work was to quantify the yield loss caused during the bleaching of kraft pulp of Pinus radiata delignified with oxygen. The material was submitted to three distinct ECF sequences (D0(EPO)D1D2, D0(EPO)D1P, and Z/EDP). At the end of each bleaching stage, the pulp brightness and the loss of gravimetric yield of the process were determined, and the generated filtrates were collected. From these filtrates, the pollutant load of the effluent was determined by measuring the content of total dissolved solids, the chemical oxygen demand, the concentration of total organic carbon carbon, and the adsorbable organic halogens. Among the whole sequences, the Z/EDP sequence had the lowest gravimetric yield, the highest pollutant load in the collected filtrate, and lowest potential for adsorbable organic halogens generation. There was good correlation between the loss of yield from the bleaching process and the organic load of the generated effluent; and among the techniques studied, the quantification of total organic carbon was the most appropriate method for the indirect quantification of the yield loss during the bleaching process of the studied material.


Assuntos
Oxigênio , Pinus , Análise da Demanda Biológica de Oxigênio , Ácido Hipocloroso , Resíduos Industriais/análise , Papel , Eliminação de Resíduos Líquidos
3.
São Paulo; SMS; 2015. [7] p. ilus, tab.
Não convencional em Português | Sec. Munic. Saúde SP, CRSNORTE-Producao, Sec. Munic. Saúde SP, Sec. Munic. Saúde SP | ID: sms-9753

RESUMO

O suicídio é um fenômeno complexo que envolve muitas pessoas além das vítimas como familiares, profissionais de saúde e de outros setores. É cercado de situações incômodas que envolvem sentimentos de impotência, o preconceito, medo e outros. São diversas as situações de vulnerabilidade para o suicídio que merecem atenção e está relacionado a múltiplos fatores (biológicos, genéticos, psicológicos, sociais, culturais e ambientais). Desta forma, é necessário desenvolver ações de vigilância, prevenção e controle de forma integral (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Suicídio , Tentativa de Suicídio , Suicídio/etnologia , Suicídio/prevenção & controle , Suicídio/psicologia , Suicídio/tendências
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