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Estudo da influ?ncia da temperatura na degrada??o termoqu?mica da biomassa de avel?s (euphorbia tirucalli Linn) / Study of the influence of the temperature in the thermochemical degradation of the biomass of avel?s (euphorbia tirucalli Linn)

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Previous issue date: 2013-10-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The bio-oil obtained from the pyrolysis of biomass has appeared as inter-esting
alternative to replace fossil fuels. The aim of this work is to evaluate the influence of
temperature on the yield of products originating from the pyrolysis process of the powder
obtained from the dried twigs of avel?s (Euphorbia tirucalli), using a rotating cylinder
reactor in laboratory scale. The biomass was treated and characterized by: CHNS,
moisture, volatiles, fixed carbon and ashes, as well as evaluation of lignin, cellulose and
hemicellulose, besides other instrumental techniques such as: FTIR, TG/DTG, DRX,
FRX and MEV. The activation energy was evaluated in non-isothemichal mode with
heating rates of 5 and 10 oC/min. The obtained results showed biomass as feedstock
with potential for biofuel production, because presents a high organic matter content
(78,3%) and fixed-carbon (7,11%). The activation energy required for the degradation
of biomass ranged between 232,92 392,84 kJ/mol, in the temperature range studied
and heating rate of 5 and 10?C/min. In the pyrolysis process, the influence of the reaction
temperature was studied (350-520 ? C), keeping constant the other variables, such
as, the flow rate of carrier gas, the centrifugal speed for the bio-oil condensationa, the
biomass flow and the rotation of the reactor. The maximum yield of bio-oil was obtained
in the temperature of 450?C. In this temperature, the results achieved where: content
of bio-oil 8,12%; char 32,7%; non-condensed gas 35,4%; losts 23,8%; gross calorific
value 3,43MJ/kg; pH 4,93 and viscosity 1,5cP. The chromatographic analysis of
the bio-oil produced under these conditions shows mainly the presence of phenol
(17,71%), methylciclopentenone (10,56%) and dimethylciclopentenone (7,76%) / O bio-?leo obtido da pir?lise da biomassa tem aparecido como alternativa
interessante para substitui??o dos combust?veis f?sseis. O objetivo deste trabalho ? avaliar
a influ?ncia da temperatura no rendimento dos produtos originados do processo de
pir?lise do p? obtido dos galhos secos do avel?s (Euphorbia tirucalli), utilizando um
reator de cilindro rotativo em escala de laborat?rio. A biomassa foi tratada e caracterizada
por: CHNS, umidade, materiais vol?teis, cinzas e carbono fixo, bem como, avalia??o
dos teores de lignina, celulose e hemicelulose, al?m de outras t?cnicas instrumentais,
tais como: FTIR, TG/DTG, DRX, FRX e MEV. A energia de ativa??o foi avaliada
no regime n?o isot?rmico com taxas de aquecimento de 5 e 10 oC/min. Os resultados
obtidos mostraram a biomassa como mat?ria prima com potencial para produ??o de biocombust?veis,
pois apresenta alto teor de mat?ria org?nica (78,3%) e carbono fixo
(7,11%). A energia de ativa??o exigida para degrada??o da biomassa variou entre
232,92 392,84 kJ/mol, no intervalo de temperatura da rea??o estudado e taxa de aquecimento
de 5 e 10oC/min. No processo de pir?lise, estudou-se a influ?ncia da temperatura
da rea??o (350-520 ?C), mantendo-se constantes as demais vari?veis, ou seja, a vaz?o
do g?s de arraste , a velocidade de centrifuga??o para condensa??o do bio-?leo, a vaz?o
de biomassa e a rota??o do reator. O rendimento m?ximo em bio-?leo foi obtido na
temperatura de 450?C. Nessa temperatura, os resultados alcan?ados foram: teor de bio?leo
de 8,12%; carv?o 32,7%; fase gasosa n?o condensada 35,4%; perdas 23,8%; poder
calor?fico superior 3,43MJ/kg; pH 4,93; viscosidade 1,5cP. A an?lise cromatogr?fica do
bio-?leo produzido nessas condi??es mostra a presen?a, principalmente, de fenol
(17,71%), metilciclopentenona (10,56%) e dimetilciclopentenona (7,76%)

Identiferoai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15856
Date18 October 2013
CreatorsAvelar, Karen Pereira Batista de
ContributorsCPF:12270202449, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783510Y4, Medeiros, Gilson Gomes de, CPF:19989849404, http://lattes.cnpq.br/9423866978987831, Pedroza, Marcelo Mendes, CPF:01910482404, http://lattes.cnpq.br/4401608528438096, Dantas, Tereza Neuma de Castro, Sousa, Jo?o Fernandes de
PublisherUniversidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Qu?mica, UFRN, BR, Pesquisa e Desenvolvimento de Tecnologias Regionais
Source SetsIBICT Brazilian ETDs
LanguagePortuguese
Detected LanguageEnglish
Typeinfo:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis
Formatapplication/pdf
Sourcereponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN
Rightsinfo:eu-repo/semantics/openAccess

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