1
De e mina ion o kine ic pa ame e s o biomass combus ion
1
Ál a ez Aa, Piza o Ca,*, Ga cía Rb, Bueno J.L.a, G. La ín Aa
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a Depa men o Chemical and En i onmen al Enginee ing. Facul y o Chemis y
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Uni e si y o O iedo, Julián Cla e ía 8, 33006, O iedo, As u ias, Spain.
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b Ins i u o Nacional del Ca bón, INCAR-CSIC, c/ F ancisco Pin ado Fe 26,
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33011. O iedo, Spain
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ABSTRACT
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The aim o his wo k is o p o ide a wide da abase o kine ic da a o he mos
9
common biomass by he mog a ime ic analysis (TGA) and di e en ial
10
he mog a ime y (DTG). Due o he cha ac e is ic pa ame e s o DTG cu es, a
11
wo-s age eac ion model is p oposed and he kine ic pa ame e s ob ained om
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model-based me hods wi h ene gy ac i a ion alues o i s and second s ages
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in he ange 1.75·104 – 1.55·105 J/mol and 1.62·104 – 2.37·105 J/mol,
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espec i ely. Howe e , i has been ound ha Flynn-Wall-Ozawa and Kissinge -
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Akahi a-Sunose model- ee me hods a e no sui able o de e mine he kine ic
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pa ame e s o biomass combus ion since he assump ions o hese wo
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me hods we e no accomplished in he ull ange o he combus ion p ocess.
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Keywo ds
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Biomass, combus ion, kine ic pa ame e s, Coa s-Red e n me hod,
21
he mog a ime ic analysis
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1. INTRODUCTION
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The impo ance o was e biomass as an ene gy sou ce is likely o inc ease
25
du ing he coming yea s as a esul o Eu opean ene gy policy a ge s
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(Eu opean En i onmen Agency (EEA), 2010). The o al amoun o po en ial
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biomass in Spain is abou 88,677,193 /yea (da a om Spanish Renewable
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Ene gies Plan 2011-2020 e e encing in (Ál a ez e al., 2015)), belonging o he
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ag icul u al and ha es ing esidues he la ges quan i y (up o 37.8% o he o al
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po en ial biomass).
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The e a e s ill some p oblems in cu en biomass combus ion u naces, such
32
as low he mal e iciency, ins abili y o hea load, and slagging (Szemmel eisz
33
e al., 2009; Yang e al., 2004). Compu a ional Fluid Dynamics (CFD) could be
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use ul in sol ing hese p oblems (Dixon e al., 2005; Ma e al., 2007), bu i is
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absolu ely essen ial ha ing a deep knowledge o he composi ion (p oxima e,
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ul ima e and s uc u al analysis) and he mal beha iou as well as he kine ics o
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he combus ion p ocess o biomass.
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The aim o his a icle is o de e mine he combus ion kine ics pa ame e s o
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he mos commonly used ypes o biomass in Spain using a he mog a ime ic
40
analyse (TGA), since his echnique is widely used in he analysis o weigh
41
loss cha ac e is ics o biomass uels (Ga cia-Ma a e e al., 2015; Kok and
42
Özgü , 2013; Maia and de Mo ais, 2016)
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2. MATERIALS AND METHODS
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2.1 Ma e ials
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Twen y eigh di e en biomass samples we e es ed o ob ain hei ac i a ion
47
ene gy, Ea, and p e-exponen ial A henius ac o , ko, alues o combus ion.
48
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These samples we e selec ed ying o ack a wide a ie y o di e en biomass
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o igins such as comme cial uels, indus ial and o es was es, ene gy c ops and
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ce eals. Thei p oxima e and ul ima e analysis da a and o he p ope ies a e
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a ailable in a da abase p e iously published by his esea ch g oup (Ga cía e
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al., 2014a, 2014b) . These samples we e p e- ea ed o assu e homogenei y
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and ep oducibili y o he ca ied-ou es s and o ha aim hey we e ai -d ied o
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a day a oom empe a u e, g inded and sie ed o 250-500 µm.
55
56
2.2. TG me hod
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10 mg o he sample we e subjec ed o he mal decomposi ion a 4 di e en
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low hea ing a es (5, 10, 15 and 20 K/min) in a Pe kin-Elme STA 6000, using
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40 ml/min o bo h pu ge (N2) and ca ie (ai ) gas.
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Pa icle diame e and, consequen ly, hea ing a es mus be low, pa icle size
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should be smalle han 500μm (Ga cia-Ma a e e al., 2015; Pa hasa a hy e
62
al., 2013; Shen e al., 2009), while oxidizing gas lux high in o de o gua an ee
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chemical-kine ic eac ion con ol, a oiding as possible empe a u e and
64
concen a ion g adien s (Pa hasa a hy e al., 2013).
65
66
2.3. Kine ic models
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In he case o combus ion some au ho s conside jus one global eac ion
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di ided in h ee di e en s ages (d ying, py olysis and cha combus ion) (Fang
69
e al., 2013; Ganga a i e al., 2005), o he s conside wo pa allel eac ions wi h
70
h ee eac ion s ages (Wang e al., 2014). Finally (Gil e al., 2010) conside s a
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wo s age eac ion, wi h a i s s ep be ween 200-365 ºC (oxida i e deg ada ion)
72
4
ollowed by combus ion o cha be ween 365-500 ºC. A simila model is
73
p oposed by (Shen e al., 2009) and (Fang e al., 2006), who apply hose
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me hods o a wo eac ion oxida ion- educ ion py olysis.
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The e a e wo main ma hema ical app oaches o ob ain he desc ip o s o
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combus ion kine ics o biomass samples: (a) model- ee me hods (iso-
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con e sional me hods) and (b) model-based me hods. Bo h app oaches depa
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om a gene al con e sion- ime ela ionship:
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dα
d =k(T)∙ (α)
(1)
Whe e (α) is he mechanis ic em and k(T) he he mal dependence e m
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ha can be de ined by A henius law:
81
k(T)=k0∙e−EaRT
⁄
(2)
Con e sion a e can be de ined as a ela ion be ween ini ial (m0), inal
82
(m∞)and ins an aneous (m ) sample mass. These da a can be ob ained om
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each sample TG p o ile.
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α= m0−m𝑡
m0−m∞
(3)
The kine ic e m (α) depends on he condi ions and he s age o he eac ion
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o s udy, bu i can be usually exp essed as (1-α) (Bahng e al., 2009; Fang e
86
al., 2006; Shen e al., 2009), i i s eac ion o de is conside ed. I o he eac ion
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model is equi ed i should be subs i u ed by one o he exp essions shown a
88
Table 1. Combining bo h exp essions, he expe imen al a e o eac ion may be
89
o mula e as:
90
dα
d =k0∙e−EaRT
⁄∙ (α)
(4)
5
I he hea ing a e β=dT/d , is included in he p e ious di e en ial equa ion,
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a new exp ession is ob ained ollowing a simple ma hema ical p ocedu e which
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can be seen in p e ious a icles such as (Gil e al., 2010; Maia and de Mo ais,
93
2016):
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dα
dT=1
β·k0∙e−EaRT
⁄∙ (α)
(5)
The e o e:
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dα
(α)=k
β∙dT→dα
(α)=𝑘0
β∙e−EaRT
⁄dT
(6)
Then he ollowing in ege , ha mus be nume ically sol ed, is ob ained:
96
g(α)=∫ dα
(α)=k0
β∫ e−EaRT
⁄dT
T
T0
α
0=k0𝐸𝑎
𝛽𝑅 𝑃(𝐸𝑎
𝑅𝑇)
(7)
The unc ion P(Ea/RT) has no exac solu ion. Thus Eq. (7) can be sol ed by
97
nume ical me hods o app oxima ions as can be seen in (Whi e e al., 2011).
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2.3.1. Model- ee me hods
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The model- ee me hods allow o e alua ing he A henius pa ame e s
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wi hou choosing he eac ion o de (Janko ić e al., 2009; Ra i e al., 2012).
101
These me hods es upon he isocon e sional p inciple, which s a es ha , a a
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cons an ex en o con e sion, he eac ion a e is a unc ion only o he
103
empe a u e (Vyazo kin and Sbi azzuoli, 2006).
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2.3.1.1. Flynn-Wall-Ozawa me hod
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The solu ion o Eq. 7 using Doyle’s app oxima ion (Eq. 8) (Doyle, 1961), is
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he Flynn-Wall-Ozawa (FWO) me hod (Eq. 9) (Flynn and Wall, 1966; Ozawa,
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1965).
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𝑙𝑛[𝑝(𝐸𝑎
𝑅𝑇)]≃−5.331−1.052𝐸𝑎
𝑅𝑇
(8)
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ln(𝛽)=𝑙𝑛(k0𝐸𝑎
𝑅𝑔(𝛼))−5.331−1.052𝐸𝑎
𝑅𝑇
(9)
Eq. 8 is alid only i 20 ≤ Ea/RT ≤ 60 (Flynn and Wall, 1966). Fo a se ies o
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measu emen s wi h di e en hea ing a es a he ixed con e sion alue α=αi,
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he plo o ln (β) s. T-1 is a s aigh line wi h he slope m = –1.052 Ea/R.
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2.3.1.2. Kissinge -Akahi a-Sunose me hod
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The Kissinge –Akahi a–Sunose me hod (KAS) is ob ained using Eq. 10,
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which is alid o 20 ≤ Ea/RT ≤ 50 (Sbi azzuoli e al., 2009).
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p(Ea
RT)≃e−EaRT
⁄
(Ea
RT)2
(10)
In KAS me hod, he ela ion be ween he empe a u e and hea ing a e is
116
gi en by Eq. 11 (Kissinge , 1957).
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ln(β
T2)=ln(k0R
Eag(α))−Ea
RT
(11)
The plo o he le side o Eq. 11 s. T-1 a cons an con e sion alue is a
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s aigh line wi h he slope m=-Ea/R.
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2.3.2. Model-based me hods. Coa s-Red e n me hod.
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Coa s-Red e n me hod uses he asymp o ic se ies expansion o
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app oxima ing he exponen ial in eg al in Eq. 7 (Coa s and Red e n, 1964).
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ln(g(α)
T2)=ln(k0R
βEa(1−2RT

Ea))−Ea
RT
(12)
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I e m 2RT/Ea is much lowe han one i can be igno ed, being he igh
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loga i hmic e m cons an :
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ln(g(α)
T2)=ln(k0R
βEa)−Ea
RT
(13)
Plo ing he le side o Eq. 13 s. T-1, Ea and k0 a e ob ained om he slope
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and in e cep espec i ely. Finally, he model ha gi es he bes linea i is
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selec ed as he chosen model.
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Se e al eac ion model o g(α) and (α) a e lis ed a Table 1. Wi h hese
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ma hema ical app oach he kine ic iple (decomposi ion model/ eac ion o de ,
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p e-exponen ial A henius ac o and ac i a ion ene gy) can be ob ained om
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he mal decomposi ion da a in a he mobalance scale (Bahng e al., 2009).
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132
3. RESULTS AND DISCUSSION
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3.1 Pa ame e s o DTG cu es
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The cha ac e is ic pa ame e s o DTG plo s, which a e p esen ed in Fig. 1,
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a e shown in Table 2. As shown in Table 2, he combus ion beha iou o
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biomass samples s udied is almos he same. The e a e wo s eps in
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combus ion o biomass, excep o cha coal, lignin and cellulose which
138
p esen ed only one s ep. The i s s ep is ela ed wi h combus ion o cellulose
139
and hemicelluloses and he second one is ela ed wi h he lignin ac ion. All he
140
empe a u es a maximum DTG (Tpeak) o i s s age a e in he ange be ween
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249-353 ºC, while he ange o second s age is 414-627 ºC. Tempe a u e a
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maximum weigh loss a e o cellulose is 338 ºC, which co espond o he i s
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s age while in he case o lignin his empe a u e is 548 ºC belonging o second
144
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s age. Thus, he i s s ep is ela ed wi h combus ion o cellulose and
145
hemicelluloses and he second one is ela ed wi h he lignin ac ion.
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Due o he da a in Table 2, a wo-s age eac ion kine ic scheme has been
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p oposed in his a icle:
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A (solid)  A’ (solid) + B1 (gas) (s age 1)
A’ (solid)  B2 (gas) + D (ash) (S age 2)
(14)
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3.2 Kine ic pa ame e s
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The samples o biomass uels we e subjec ed o ou hea ing amps a 5, 10,
151
15 and 20 K/min. Ob ained da a was adjus ed using p e iously desc ibed FWO,
152
KAS and Coa s-Red e n me hod as well as nume ically using Scien is so wa e,
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supposing i s eac ion o de in all cases, which showed a eally good
154
ma hema ical adjus . In ha way, a ou poin s aigh line was ob ained o each
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con e sion alue om 10 o 90%, so a alue o Ea is ob ained o each
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con e sion (FWO and KAS me hods) while only one hea ing amp da a (15
157
K/min) we e necessa y when Coa s-Red e n o nume ical me hods we e used
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o ob ain he kine ic iple . The ob ained kine ic da a a e shown a Table 3 and
159
Table 4 o Coa s-Red e n and nume ical solu ions espec i ely.
160
When FWO o KAS me hod we e applied, hei pa icula assump ions we e
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only accomplished in he a ange o con e sion belonging o hemicelluloses and
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cellulose ac ions, while a he le el o con e sion o which he combus ion o
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lignin s a s he assump ions we e no accomplished (Fig 2). In Fig 2 he alues
164
o Ea/RT o FWO and KAS me hods a e plo ed agains empe a u e as well as
165
do ed lines o maximum and minimum Ea/RT alues o bo h me hods. I can
166
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be seen clea ly ha he assump ions o FWO and KAS me hods we e only
167
accomplished in he i s s age wi h Ea/RT alues ( ed and g een lines) be ween
168
do ed lines while hese colou ed lines a e below minimum do ed line when he
169
second s age akes place. In comme cial lignin and cha coal samples, he
170
assump ions we e no accomplished a all. Taking in o accoun ha cha coal is
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mainly composed o lignin, i is clea ha FWO and KAS me hods canno
172
p edic ac i a ion ene gy o biomass combus ion when lignin decomposi ion
173
akes place.
174
Rega ding Coa s-Red e n and nume ical me hod kine ic da a, he ac i a ion
175
ene gy in bo h s ages is almos he same al hough i mus be s a ed ha in mos
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samples his alue is sligh ly highe in second s age. Howe e , he ac i a ion
177
ene gy o lignin is lowe han cellulose, his is hough o be because o he
178
syne gis ic e ec . Since bo h s ages a e o e lapped, in he Coa s-Red e n
179
me hod a 𝛾- ac o is used in o de o link bo h s ages:
180
dα
dT=γ(dα
dT)s age 1+(1−γ)(dα
dT)s age 2
(15)
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The 𝛾- ac o is modelled as a modi ied Gompe z unc ion (Collado e al.,
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2016):
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𝛾=1 − 𝐴 𝑒𝑥𝑝{−exp(𝜇𝑒
𝐴(𝑇𝑐−𝑇)+1)}
(16)
Figu es 3a and 3b show he simula ions o he Coa s-Red e n me hod. As i
184
can be seen in Table 5, whe e he Gompe z pa ame e s a e shown, A alues
185
a e close o 1 and Tc is he u ning poin be ween bo h s ages, while µ alues
186
a e ela ed wi h he a e o change o he 𝛾- ac o .
187
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Table 2. DTG da a o biomass samples
322
Sample
Fi s s age
Second s age
Tpeak(ºC)
Tempe a u e
ange (ºC)
Tpeak(ºC)
Tempe a u e
ange (ºC)
Cellulose
338
300-360
-
-
Lignin
-
-
548
450-600
Almond shell
298
250-390
477
400-720
Apple ee lea es
311
220-350
414
410-600
Bee oo pelle s
342
210-380
541
400-640
B ique e
343
260-400
509
410-550
Cha coal
-
-
490
400-900
Ches nu ee chips
335
260-370
473
400-520
Cocoa bean husk
312
225-350
627
425-634
Co ee bean husk
319
220-360
502
440-520
Co ncob
289
250-340
454
400-550
Eucalyp us ee chips
340
250-370
486
420-520
Ex ac ed oli e pomace
328
230-360
550
400-725
Go se
339
250-390
560
450-570
G ape seed lou
340
255-375
546
400-775
Miscan hus
307
240-340
550
450-550
Oli e s one
340
260-360
418
400-820
Oli e ee p uning
342
250-375
469
430-570
Peppe plan
311
220-374
460
400-807
Pine and pineapple lea e pelle s
324
250-360
422
400-740
Pine ke nel shell
249
270-370
515
400-820
Pineapple lea
344
250-380
496
420-570
Rice husk
334
260-360
450
400-540
Sain oin
301
230-330
456
390-522
Sc ubland p uning
334
260-370
538
400-760
This le
345
240-400
473
420-550
Vine shoo
318
250-380
468
420-500
Whea s aw
312
260-360
543
420-650
Whea s aw pelle s
300
230-365
458
400-528
323

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Table 3. Kine ic pa ame e s ob ained by means o Coa s-Red e n me hod.
324
Sample
S age 1
S age 2
ko
Ea (J/mol)
R2
ko
Ea (J/mol)
R2
Cellulose
9.47E+17
2.12E+05
0.997
-
-
-
Lignin
-
-
-
6.87E+03
6.95E+04
0.98
Almond shell
2.07E+03
4.82E+04
0.994
1.00E+00
1.71E+04
0.94
Apple ee lea es
3.54E+01
2.94E+04
0.997
2.65E+00
2.06E+04
0.996
Bee oo pelle s
5.36E+00
2.16E+04
0.998
3.99E+00
2.32E+04
0.98
B ique e
4.65E+02
4.28E+04
0.997
2.24E+03
5.55E+04
0.96
Cha coal
-
-
-
9.17E-01
2.29E+04
0.98
Ches nu ee chips
1.35E+03
4.66E+04
0.998
2.83E+03
5.38E+04
0.98
Cocoa bean husk
2.86E+01
2.90E+04
0.995
6.28E-01
1.51E+04
0.99
Co ee bean husk
1.06E+02
3.46E+04
0.998
7.10E+03
6.25E+04
0.96
Co ncob
1.65E+07
8.69E+04
0.994
3.20E+00
1.95E+04
0.93
Eucalyp us ee chips
4.60E+02
4.18E+04
0.9995
1.03E+04
6.30E+04
0.98
Ex ac ed oli e pomace
5.96E+01
3.23E+04
0.993
5.08E-01
1.46E+04
0.92
Go se
3.07E+01
3.07E+04
0.997
3.31E+02
4.71E+04
0.95
G ape seed lou
8.85E+00
2.56E+04
0.995
3.09E+02
5.70E+04
0.96
Miscan hus
2.56E+02
3.79E+04
0.996
6.76E+02
5.09E+04
0.97
Oli e s one
1.37E+03
4.63E+04
0.98
7.33E+01
4.76E+04
0.91
Oli e ee p uning
1.48E+02
3.64E+04
0.9991
2.26E+00
1.92E+04
0.92
Peppe plan
4.58E+00
2.14E+04
0.9993
7.02E+01
4.73E+04
0.95
Pine and pineapple lea e pelle s
1.05E+03
4.51E+04
0.994
1.09E-01
7.35E+03
0.97
Pine ke nel shell
2.84E+02
4.05E+04
0.996
7.91E+01
4.81E+04
0.97
Pineapple lea
1.31E+02
3.69E+04
0.997
5.33E+02
4.92E+04
0.95
Rice husk
7.31E+03
5.39E+04
0.9991
4.13E+01
3.28E+04
0.92
Sain oin
1.64E+02
3.49E+04
0.996
1.88E+02
4.09E+04
0.995
Sc ubland p uning
2.26E+01
2.90E+04
0.995
2.86E+00
2.09E+04
0.92
So ghum
2.93E+03
4.99E+04
0.998
2.01E+00
1.81E+04
0.98
This le
9.64E+01
3.46E+04
0.998
5.61E+01
3.50E+04
0.99
Vine shoo
5.12E+03
5.16E+04
0.998
8.68E+02
4.82E+04
0.96
Whea s aw
1.93E+06
7.75E+04
0.96
4.13E+00
2.34E+04
0.92
Whea s aw pelle s
1.35E+04
5.46E+04
0.995
1.51E+01
2.75E+04
0.96
325
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Table 4. Kine ic pa ame e s ob ained by nume ical solu ion.
326
Sample
S age 1
S age 2
ko
Ea
R2
ko
Ea
R2
Cellulose
3.24E+10
1.26E+05
0.997
-
-
-
Lignin
4.49E+05
9.73E+04
0.99993
Almond shell
2.97E+02
3.83E+04
0.9997
7.11E+01
4.36E+04
0.999996
Apple ee lea es
1.29E+02
3.42E+04
0.9998
2.57E+01
3.23E+04
0.999998
Bee oo pelle s
3.26E+00
1.75E+04
0.999996
1.26E+03
6.04E+04
0.9999995
B ique e
1.98E+04
5.98E+04
0.99996
3.90E+09
1.48E+05
0.9999997
Cha coal
1.09E+00
2.10E+04
0.9996
Ches nu ee chips
1.76E+05
6.88E+04
0.9998
3.01E+08
1.24E+05
0.99995
Cocoa bean husk
2.48E+02
3.77E+04
0.9998
9.87E+00
2.91E+04
0.999997
Co ee bean husk
9.03E+02
4.35E+04
0.999996
4.70E+10
1.62E+05
0.999997
Co ncob
3.99E+07
9.06E+04
0.998
1.30E+03
5.29E+04
0.999996
Eucalyp us ee chips
2.02E+03
4.79E+04
0.99995
3.69E+11
1.72E+05
0.9999997
Ex ac ed oli e pomace
2.04E+02
3.69E+04
0.9994
4.11E+01
4.11E+04
0.99998
Go se
1.28E+03
4.72E+04
0.999995
3.64E+08
1.38E+05
0.999997
G ape seed lou
1.19E+02
3.64E+04
0.99991
5.80E+00
2.84E+04
0.99997
Miscan hus
3.11E+03
4.87E+04
0.9998
4.30E+07
1.22E+05
0.999998
Oli e s one
2.00E+02
3.63E+04
0.9995
1.80E+00
2.09E+04
0.99998
Oli e ee p uning
2.31E+03
4.85E+04
0.99995
2.15E+03
5.89E+04
0.999991
Peppe plan
2.10E+01
2.68E+04
0.999993
3.58E+11
2.37E+05
0.999999994
Pine and pineapple lea e pelle s
7.78E+04
6.46E+04
0.99995
1.20E+00
1.62E+04
0.999994
Pine ke nel shell
7.07E+03
5.51E+04
0.99997
2.03E+02
5.66E+04
0.999998
Pineapple lea
3.53E+03
5.15E+04
0.999995
3.13E+04
7.61E+04
0.9999991
Rice husk
1.57E+04
5.69E+04
0.99991
1.85E+04
6.95E+04
0.99997
Sain oin
2.00E+03
4.53E+04
0.9998
2.11E+04
6.88E+04
0.999994
Sc ubland p uning
4.09E+03
5.24E+04
0.99998
3.57E+03
6.21E+04
0.99998
So ghum
1.09E+04
5.54E+04
0.9997
1.79E+01
2.81E+04
0.999980
This le
3.65E+03
5.08E+04
0.999991
2.35E+05
8.64E+04
0.999998
Vine shoo
3.24E+04
5.97E+04
0.99992
3.31E+10
1.54E+05
0.9999992
Whea s aw
2.59E+13
1.55E+05
0.9998
1.25E+01
3.06E+04
0.99997
Whea s aw pelle s
6.25E+06
8.21E+04
0.99992
3.90E+04
1.54E+05
0.999998
327
19
Table 5. Gompe z model pa ame e s o he biomass samples analysed.
328
Sample
A
µ (K-1)
Tc (K)
Almond shell
0.999
0.016
597.9
Apple ee lea es
1.292
0.074
591.3
Bee oo pelle s
0.852
0.029
638.8
B ique e
0.957
0.031
637.8
Cha coal
-
-
-
Ches nu ee chips
1.000
0.064
633.7
Cocoa bean husk
1.000
0.145
594.5
Co ee bean husk
0.879
0.032
606.9
Co ncob
1.014
0.028
573.2
Eucalyp us ee chips
0.949
0.019
621.2
Ex ac ed oli e pomace
0.996
0.017
589.7
Go se
0.976
0.012
603.6
G ape seed lou
1.372
0.018
603.2
Miscan hus
1.000
0.017
583.0
Oli e s one
1.011
0.035
616.0
Oli e ee p uning
1.016
0.023
605.2
Peppe plan
0.677
0.050
593.6
Pine and pineapple lea e pelle s
1.251
0.029
595.8
Pine ke nel shell
1.000
0.011
595.2
Pineapple lea
0.988
0.021
613.0
Rice husk
1.002
0.029
606.9
Sain oin
1.509
0.056
586.2
Sc ubland p uning
1.031
0.019
600.4
So ghum
1.000
0.052
600.5
This le
1.944
0.016
612.1
Vine shoo
0.991
0.018
593.9
Whea s aw
1.000
0.068
588.7
Whea s aw pelle s
0.976
0.023
570.8
329
20
FIGURE CAPTIONS
330
Fig. 1. DTG cu es o he combus ion p ocess (β = 15 K/min) o biomass
331
samples analysed. (PPLP in b is he pine and pineapple lea e pelle sample).
332
Fig 2. Ma ches be ween DTG and Ea alues in FWO and KAS me hods.
333
Fig. 3a. Simula ions o CR me hod; 1. Almond shell; 2. Apple ee lea es; 3.
334
Bee oo pelle s; 4. B ique e; 5. Cha coal; 6. Ches nu ee chips; 7. Cocoa
335
bean husk; 8. Co ee bean husk; 9. Co ncob; 10. Eucalyp us ee chips; 11.
336
Ex ac ed oli e pomace; 12. Go se; 13. G ape seed lou ; 14. Miscan hus; 15.
337
Oli e s one; 16. Oli e ee p uning.
338
Fig. 3b. Simula ions o CR me hod; 17. Peppe plan ; 18. Pine and pineapple
339
lea e pelle s; 19. Pine ke nel shell; 20. Pineapple lea ; 21. Rice husk; 22.
340
Sain oin; 23. Sc ubland p uning; 24. So ghum; 25. This le; 26. Vine shoo ; 27.
341
Whea s aw; 28. Whea s aw pelle s.
342
21
343
Fig. 1. DTG cu es o he combus ion p ocess (β = 15 K/min) o biomass
344
samples analysed. (PPLP in b is he pine and pineapple lea e pelle sample)
345

22
346
Fig 2. Ma ches be ween DTG and Ea alues in FWO and KAS me hods
347
0
10
20
30
40
50
60
70
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 100 200 300 400 500 600 700 800 900
Ea/RT
DTG, %weigh /ºC
Tempe a u e, ºC
DTG Ches nu ee chips
Ea/RT (FWO)
Ea/RT (KAS)
Ea/RT min (FWO and KAS)
Ea/RT maximum (FWO)
23
348
Fig. 3a. Simula ions o CR me hod; 1. Almond shell; 2. Apple ee lea es; 3.
349
Bee oo pelle s; 4. B ique e; 5. Cha coal; 6. Ches nu ee chips; 7. Cocoa
350
bean husk; 8. Co ee bean husk; 9. Co ncob; 10. Eucalyp us ee chips; 11.
351
Ex ac ed oli e pomace; 12. Go se; 13. G ape seed lou ; 14. Miscan hus; 15.
352
Oli e s one; 16. Oli e ee p uning.
353
24
354
Fig. 3b. Simula ions o CR me hod; 17. Peppe plan ; 18. Pine and pineapple
355
lea e pelle s; 19. Pine ke nel shell; 20. Pineapple lea ; 21. Rice husk; 22.
356
Sain oin; 23. Sc ubland p uning; 24. So ghum; 25. This le; 26. Vine shoo ; 27.
357
Whea s aw; 28. Whea s aw pelle s.
358