Evaluation of Tucumã Endocarp (Astrocaryum Aculeatum) as a New Biomass Resource for Application in Thermal Conversion Processes

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Engineering Conferences International ECI Digital Archives BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals Proceedings Spring 5-10-2012 Evaluation of Tucumã Endocarp (Astrocaryum Aculeatum) as a New Biomass Resource for Application in Thermal Conversion Processes Katia Tannous University of Campinas J.B. Lourenco University of Campinas Y.J.R. Ordoñez University of Campinas Follow this and additional works at: http://dc.engconfintl.org/bioenergy_iv Part of the Chemical Engineering Commons Recommended Citation Katia Tannous, J.B. Lourenco, and Y.J.R. Ordoñez, "Evaluation of Tucumã Endocarp (Astrocaryum Aculeatum) as a New Biomass Resource for Application in Thermal Conversion Processes" in "BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals", Manuel Garcia-Perez,Washington State University, USA Dietrich Meier, Thünen Institute of Wood Research, Germany Raffaella Ocone, Heriot-Watt University, United Kingdom Paul de Wild, Biomass & Energy Efficiency, ECN, The Netherlands Eds, ECI Symposium Series, (2013). http://dc.engconfintl.org/bioenergy_iv/11 This Conference Proceeding is brought to you for free and open access by the Proceedings at ECI Digital Archives. It has been accepted for inclusion in BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals by an authorized administrator of ECI Digital Archives. For more information, please contact franco@bepress.com.

University of Campinas School of Chemical Engineering Evaluation of Tucumã Endocarp (Astrocaryum Aculeatum) as a New Biomass Resource for Application in Thermal Conversion Processes K. Tannous, J.B. Lourenço and Y.J.R. Ordóñez 1

Outline Introduction and Motivation Objectives Materials and Methods Results and Discussion Conclusions 2

Introduction Social responsability Fonte: LABPALM, 2010 tucumã fruit endocarp 3

Objectives To evaluate tucumã endocarp as a biomass resource for application in thermo-conversion process (pyrolysis-char) using the fluidized bed technology. Characterization of physical properties and fluid dynamics behavior (binary mixtures) Characterizations of the chemical and thermal properties Thermogravimetric analysis and kinetics of the thermal decomposition 4

1 st Step - Experimental Work Characterization of the Physical Properties and Fluid dynamics Behavior 5

Materials and Methods Physical Properties of Biomass and Inert Material d p (mm) D b/i (-) X b/i (%) j (-) r p (kg/m 3 ) r s (kg/m 3 ) Geldart Classif. Sand 331.6 0.85 2636.0 2656.7 B tucumã fruit endocarp 502.5 1.5 0.81 1442.6 B 5 1017.5 3.1 10 0.85 1428.3 B 1115.0 15 2017.4 6.1 20 0.89 1424.6 D 6

Materials and Methods Experimental Setup (Fluid Dynamics) T room and P atm Cyclone Humidity, Temp. indicator Column D=0.092 m Pressure transducer Rotameters blower Perfurated plate (e d =5.9%) Computer/data acquisition 7

Experimental Procedures Materials and Methods Characteristic Velocities Porosities and Bed Expansion D = 6.1; χ b/i = 20 w-% 8

Materials and Methods States of Fluidization for Binary Mixtures Increasing velocity (a) U if ~ U af = 0.13 m/s (b) U S = 0.21 m/s (c) U cf = 0.42 m/s Total seg. Partial seg. mixture Mixture tucumã/sand, D=6.1, χ= 20% 9

Results and Discussion Characteristics velocities, porosities and bed expansion Influence of the mass fraction ratio Influence of the mean diameter ratio 10

Results and Discussion Characteristics Velocities and Porosities Influence of the mass fraction ratio Influence of the diameter ratio 0.5 U (m/s) ε (-) 0.9 0.5 U (m/s) ε (-) 0.9 0.4 0.3 U cf ε cf 0.8 0.7 0.4 0.3 U cf ε cf 0.8 0.7 0.2 0.1 0 χ (-) U S U af U if ε af 0 5 10 15 20 25 0.6 0.5 0.4 0.3 0.2 0.1 U S U af U if ε af 0.6 0.5 0.4 d p (mm) 0 0.3 300 600 900 1200 1500 1800 2100 2400 D = 6.1 χ = 20% 11

Results and Discussion Bed Expansion Influence of the mass fraction ratio Influence of the diameter ratio 0.9 0.8 ε (-) 0.9 0.8 ε (-) 0.7 0.7 0.6 0.5 0.4 0% (Sand) 5% 10% 15% 20% 0.6 0.5 0.4 502,48 502 µm mm 1017,53 1012 mm µm 2017,37 mm µm 0.3 U (m/s) 0.2 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.3 U (m/s) 0.2 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 D = 6.1 χ = 20% 12

2 nd Step - Experimental Work Characterization of the Chemical and Thermal Properties 13

Results and Discussion d p_ref. = 502.5 μm Ultimate analysis (wt.% ) C H N S O Ash 1 47.99 5.99 0.29 < 0.1 44.23 1.50 Chemical composition (wt.%) Pectin Hemicelluloses Cellulose Lignins (S+InS) 0.02 17.36 40.89 37.05 Proximate analysis (wt.%) Moisture Volatile matter Ash Fixed Carbon 6.80 76.75 1.50 21.75 Heating Value (MJ/kg) Higher Lower Experimental Tillman (1978) Mendeleev (1949) 20.33 20.68 18.95 1 from proximate analysis; * Dry mass basis 15

3 rd Step - Experimental Work Characterization of Thermal Decomposition and Kinetic Study 16

Mass (%) Results and Discussion Thermal Decomposition at different heating rates (b) 100 90 80 70 60 50 40 30 20 10 I II DTG mass 5 ºC/min 10 ºC/min 20 ºC/min 40 ºC/min 0.02-0.03-0.08-0.13-0.18-0.23-0.28-0.33-0.38 0-0.43 200 300 400 500 600 700 800 900 Temperature (ºC) b DTG (%/s) Thermogravimetric Balance (Shimadzu, TGA-50, Japan) Inert gas (N 2 ) and flow rate (50 ml/min); sample mass(10 mg); d p = 502.5 mm 17

Kinetic Study of Biomass Thermal Decomposition Isoconversional (Model-free) methods Kinetic parameter - Apparent Activation Energy (E a ) Method 1 Method 2 Coats-Redfern (1965) modified by Burnham and Braun (1999) Ozawa-Flynn-Wall (1965,1966) reaction rate constant by the Arrhenius equation, k (nonisothermal) Conversion, a = m i m/m i -m f (0.15-0.75) Graph - ln[β/t a2 ] versus 1/T a E a = ar Graph log β versus 1/T a E a = ar/0.4567 18

Apparent Activation Energy (kj/mol) dα/dt ( o C -1 ) Evolution of Apparent Activation Energy (E a ) Results and Discussion 190 180 170 160 150 b 5 ºC/min 10 ºC/min 20 ºC/min 40 ºC/min 2.0E-4 1.6E-4 1.2E-4 140 130 8.0E-5 120 4.0E-5 Ea O-F-W 110 Ea Coats-Redfern 100-1.1E-19 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Conversion, α (-) Apparent Activation Energy and Nonisothermal Reaction Rate as a function of Conversion 19

Conclusions Fluid dynamics Behavior 3 states and 4 characteristic velocities of fluidization (U if, U af, U S, U cf ); Influences: D (1.5 6.1) X (5% to 20%) characts. U and e p, e Characteristic of the Chemical and Thermal Properties C and O contents (92%); high cellulose (41%) and lignin (37%) contents; high volatile matter (77%) and low ash (1.5%) contents; Heating value: High (20 MJ/kg) and low (19 MJ/kg). Thermal decomposition and kinetic analysis: high decomposition of hemicellulose and cellulose (+lignin) with 52% of mass loss between 200-500 o C; Kinetic analysis: 0.45 < a < 0.75 - E a = 163-172kJ/mol, corresponds to the decomposition of the cellulose (bonds more stable, requiring greater energy). 20