CHEMICAL ENGINEERING TRANSACTIONS
VOL. 32, 2013
A publication of
The Italian Association
of Chemical Engineering
Online at: www.aidic.it/cet
Chief Editors: Sauro Pierucci, Jiří J. Klemeš
Copyright © 2013, AIDIC Servizi S.r.l.,
I SBN 978-88-95608-23-5; I SSN 1974-9791
Evaluation of Pyrolysis and Steam Gasification Processes
of Sugarcane Bagasse in a Fixed Bed Reactor
Jaiver Efren Jaimes Figueroa*, Y. Camacho Ardila, B. Hoss Lunelli, R. Maciel
Filho, M. R. Wolf Maciel
Department of Process and Product Development. School of Chemical Engineering. Av. Albert Einstein, 500. Cidade
Universitária "Zeferino Vaz", CEP 13083-862. State University of Campinas - UNICAMP. Campinas-SP, Brazil.
jaiverej@hotmail.com
Sugarcane bagasse is the main byproduct of sugarcane mill, ready available at the production site so that
it may be a suitable raw material for the production of biofuels, chemicals and electricity. Among the
methods that have been widely studied, there are thermochemical processes such as gasification,
pyrolysis and direct combustion. The direct combustion is used to produce electricity while the pyrolysis
and gasification are used to obtain high value-added products such as bio-oil and synthesis gas (Syngas).
In this study we performed a comparison between the experimental results by pyrolysis and gasification
reactions. The pyrolysis and gasification of sugarcane bagasse was carried out, using a laboratory-scale
fixed bed reactor in order to produce bio-oil (pyrolysis) and Syngas (gasification). The gasification and
pyrolysis were studied and evaluated the char, tar and gas production as well as the composition of the
gas produced. For the pyrolysis temperature was varied from 500 °C to 900 °C and a quite broad reaction
time range was considered. In gasification were evaluated the reaction temperature equal to 900 °C,
reaction time and steam/bagasse ratio equal 2.0. The behavior for both process was presented.
1. Introduction
The thermochemical processes such as pyrolysis and gasification produce, besides hydrogen, a gas
mixture containing carbon monoxide (CO), carbon dioxide (CO
2
) and light hydrocarbons. This gas is used
in many industrial applications such as production of methanol, hydrogen, ammonia, sulphuric acid,
formaldehyde or like saturated steam gas turbine
The pyrolysis process at low temperatures (400 - 600 °C) is formed of liquid and gaseous products are
formed from high temperature (900 °C). Gasification and pyrolysis are similar processes however the
gasification takes place in the presence of oxygen in the form of air or steam whereas the pyrolysis occurs
in the absence of oxygen (Zhou et al., 2008).
Gases and liquids produced in the pyrolysis and gasification processes can be used as energy, as heat
and electricity or chemicals production. For example, gases with high contents of CO and H
2
can be a
source of synthesis gas (for methanol, DME or Fischer-Tropsch synthesis) or H
2
(fuel cells) (Baumlin et al.,
2006).
Products with high added value such as hydrogen or synthesis gas can be produced from pyrolysis of
bagasse using a fixed bed reactor. The synthesis gas comprises a mixture of hydrogen and carbon
monoxide (H
2
+CO). The pyrolysis of sugarcane bagasse can be accomplished in two ways, with or without
carrier gas (nitrogen). The literature emphasizes that it is very difficult to perform this process without the
use of carrier gas (N
2
), this occurs because the formation of soot. The presence of the carrier gas provide
a uniform distribution of the reagent in the reactor bed (Skoulou and Zabaniotou, 2013).
The gasification process can be defined as a process of partial combustion of sugarcane bagasse
because it uses an amount of air less than that required stoichiometrically. The gaseous product is
obtained consisting of hydrogen (H
2
), carbon monoxide (CO) and carbon dioxide (CO
2
), comprising the
synthesis gas (Lan et al., 2013).
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