Analysis of the Pyrolytic Fuel Properties of Empty Fruit Bunch Briquettes
Bemgba Bevan Nyakuma,
Briquetting is technique for mechanically compacting and densifying
loose materials into a uniform solid fuel aimed at improving the physical and
thermochemical properties such as energy density, moisture content. This study
is aimed at investigating the pyrolytic fuel properties of briquettes using
DSC thermal analysis. The EFB Briquettes were pulverized and sieved in a Retsch
analysis sieve with screen size 800 micron. The Higher Heating Value (HHV) of
the fuel was determined using a bomb calorimeter according to the ASTM standard
D-2015 technique. Proximate analysis was carried to determine the moisture content,
volatile matter, fixed carbon and ash content of the fuel. The powdered EFB
briquette was analyzed using a Perkin Elmer DSC 7 thermal analyzer under pyrolysis
conditions from 30 to 500°C at a constant heating rate of 10°C min-1
with nitrogen (N2), flow rate of 25 mL min-1 as sweeping
gas. The calorific changes during DSC analysis were recorded and analyzed. A
Scanning Electron Microscope (SEM) was used to investigate the surface composition
and particle size distribution of the fuel. Surface analysis revealed that 57%
of the fuel particles are in the 151-250 μm range. The HHV value of the
fuel obtained was 17.57 MJ kg-1 and specific heat Cp =
1,397 J kg-1 K-1. From the FTIR spectra of the fuel, the
product gases as H2, CO, CO2, CH4 and CmHn
can be reasonably predicted. The results indicated that EFB briquette has good
fuel properties and can be utilized as a fuel in biomass pyrolysis.
Received: September 02, 2012;
Accepted: November 17, 2012;
Published: January 10, 2013
The production of crude palm oil in Malaysia generates significant quantities
of solid lignocellulosic biomass as waste. The palm based solid bio-waste comprises;
53% Empty Fruit Bunches (EFB), 32% palm mesocarpfibre and 15% palm shell (Baharuddin
et al., 2009; Wahid et al., 2004;
Yusoff, 2006). Current production data estimate around
7 million tonnes of EFB, 4.5 million tonnes of palm fibre and 1.9 million tonnes
of shell, are generated annually from palm oil production in Malaysia (Mae
et al., 2000). With the generation of solid palm waste set to increase
5% annually, socioeconomic and environmental problems such as global warming
and the greenhouse effect are imminent. Consequently, urgent practical and sustainable
solutions are required to curtail the future potential effects of increased
solid bio-waste from palm oil production. While efforts are currently focused
on the utilization of Empty Fruit Bunch (EFB) as fuel in boilers to generate
steam and electricity in palm oil mills; a large fraction is still simply incinerated
or burnt in open air (Mahlia et al., 2003; De
Souza et al., 2010; Lahijani and Zainal, 2011).
The low efficiency of current conversion technologies has led to increased emission
of large quantities of CO2 and other greenhouse gases (GHGs) such
as NOx, SOx into the atmosphere. Consequently researchers
in Malaysia are currently exploring novel, efficient and sustainable process
technologies to convert palm oil based waste into a renewable source of energy.
The efficiency of EFB fibres currently used as boiler fuel in palm oil mills
can be improved by briquetting. This is a technique for mechanically densifying
biomass by compacting loose materials into a uniform solid fuel. This is known
to improve the physical and thermochemical properties such as homogeneity, energy
density, energy content, moisture content as well as storage and handling of
the fuel (Grover and Mishra, 1996; Bhattacharya
and Shrestha, 1990; Bhattacharya et al., 1989).
These properties make briquettes ideal fuels for application in biomass conversion
technologies such as gasification and pyrolysis which are considered promising
technologies for converting CO2 neutral biomass into clean energy
for future applications (McKendry, 2002; Demirbas,
2001). Pyrolysis is the thermal decomposition of biomass into solid charcoal,
liquid (pyrolysis oil) and H2 rich gases in the absence of oxygen
(McKendry, 2002). The rate of biomass pyrolysis is influenced
by biomass properties and operating parameters such as moisture content, temperature,
heating rate, particle size and catalysts (Chen et al.,
2003; Di Blasi et al., 1999; Li
et al.,2004; Lappas et al., 2002).
Previous studies on biomass pyrolysis have focused on the parametric of biomass
pyrolysis using thermal analytical techniques such as Differential Scanning
Calorimetry (DSC) and Thermogravimetric analysis (TGA) (Rath
et al., 2003; Stenseng et al., 2001;
He et al., 2006). Studies by Mahlia
et al. (2003), Lahijani and Zainal (2011),
Mohammed et al. (2005), Sulaiman
and Abdullah (2011) and Abdullah et al. (2010)
have all highlighted the potential of EFB as a feedstock fuel for hydrogen production.
Studies by Yang et al. (2004); Yang
et al. (2006) have investigated the pyrolysis of palm oil waste using
Thermogravimetric Analysis-Fourier Transform Infrared (TGA-FTIR) for the production
of hydrogen. Other applications of EFB include for the production of chemicals,
biofuels (Kassim et al., 2011; Kelly-Yong
et al., 2011; Bari et al., 2010) and
agricultural inputs such as organic manure (Sung et
al., 2010; Affendy et al., 2011). Nonetheless,
the thermochemical, kinetic mechanisms and pyrolytic fuel properties of biomass
fuels requires further investigation. Studies on the fuel properties on EFB
briquettes as a fuel for pyrolysis have not been previously reported in literature.
Therefore, this study is aimed at investigating the pyrolytic fuel properties
of EFB briquettes using DSC analysis, FTIR and SEM microscopy for clean energy
applications for the future.
MATERIALS AND METHODS
The EFB briquettes with average dimensions (4.9x2.5x0.8) cm used in this study
were acquired from FeldaSemenchuSdnBhd, Johor, Malaysia. Fig.
1, shows the briquettes produced from Empty Fruit Bunches (EFB).The EFB
briquettes were pulverized in a high speed crusher machine (Kimah Malaysia,
Model RT 20) fitted with a 1 mm screen. The resulting briquette powder was sieved
for a second time in a Retsch analysis sieve (D-42759, Haan Germany, screen
800 micron) to obtain particles with particle size <800 μm reportedly
(He et al., 2006) ideal for DSC analysis. The
proximate analysis of fuel was carried out to using ASTM standard techniques
for determining the moisture content, volatile matter, ash content and fixed
carbon content of biomass fuels. The Higher Heating Value (HHV) of the EFB briquette
was analyzed using a bomb calorimeter (IKA calorimeter system, Model C2000)
according to ASTM standard D-2015 technique. Using a table top SEM scanning
electron microscope (Model Hitachi TM 3000) high resolution micrographs were
obtained at a magnification of x50 and x100 using Mode A analytical settings
to analyze the surface composition and particle size distribution of the fuel.
FTIR, Fourier Transform Infra-Red spectroscopic (Model Perkin Elmer Spectrum
One) analysis was carried on the fuel and the IR spectra recorded from 4000
to 500 cm-1. Subsequently, the pyrolysis of the powdered EFB briquette
was carried out using a computerized Perkin-Elmer DSC 7 thermal analyzer.
||(a) Empty fruit bunch (EFB) and (b) Empty fruit bunch (EFB)
The powdered sample was placed in an aluminium crucible with a lid and heated
in the DSC furnace from 30 to 500°C at a constant heating rate of 10°C
min-1 using nitrogen (N2) (flow rate of 25 mL min-1)
as sweeping gas. After each run the furnace was cooled and the DSC traces of
each run obtained for each sample. The changes observed during DSC analysis
were recorded and analyzed in MS EXCEL to obtain the calorific requirement from
which the specific heat capacity (Cp) of the fuel can be deduced.
The calorific requirement of biomass pyrolysis is a measure of the heat required
to heat the sample and to complete the reaction. It can be calculated from the
formulae (Jalan and Srivastava, 1999; Liliedahl
and Sjostrom, 1998; Sharma and Rao, 1998; Rath
et al., 2002):
Although the calculation method for determining the calorific requirement of
biomass from Eq. 1 is widely accepted, it is complex and has
numerous limitations. According to a study by He et
al. (2006), the complexity of the calculation method is due to the large
changes in biomass temperature during pyrolysis which in addition to the lack
of reliable property data for biomass feedstock such as Cp accounts
for the discrepancies in the calculations and the difficulty in quantifying
the specific heat and reaction heat Qp.
However, the calorific requirement of biomass can also be deduced experimentally
by DSC thermal analysis by integrating the DSC curves obtained during thermal
analysis as expressed mathematically in Eq. 2 (He
et al., 2006):
where, Q is calorific requirement; Cp,b; Cpch; specific
heat capacity of biomass and char respectively; m,b; m,ch;
mass of biomass and char respectively; Qp, reaction heat of biomass;
Hp heat flow due to reaction heat of biomass pyrolysis; dT, temperature
change; t, time of DSC experiment.
RESULTS AND DISCUSSION
Proximate analysis and heating value: The results of the proximate analysis
(wt. %) and heating value (HHV) of the EFB briquette are presented in Table
1. The FB briquette contains a high percentage of volatile matter (>70%),
low moisture content (<10%), ash content (<5%) and fixed carbon (<20%).
The low moisture content (8.17%) is an indication that the thermal conversion
efficiencyof the fuel will be considerably high. This is consistent with the
findings of Basu (2010) which show a direct correlation
between moisture content and the heating value of biomass fuels. Furthermore,
the low EFB briquette ash content (4.56%) indicates a low risk of slaggingand
fouling of the thermal conversion equipment during conversion.The ratio of volatiles
to fixed carbon ratio (VM/FC) for the fuel was 4.65, which is in good agreement
with the typical values of >4.0 for biomass species.
The HHV of the EFB briquette (~18 MJ kg-1) is lower than the values
for coal, due to the low fixed carbon content, high oxygen content and low density
of the fuel (McKendry, 2002; Basu,
2010). Thehigher heating value (HHVs) of the fuel was also calculated from
the proximate analysis using the Demirbas formulae Eq. 3 as
a function of Fixed Carbon (FC) (Demirbas, 1997):
The calculated HHV value is comparable to the experimental HHV of the EFB briquette
sample and can therefore be used as an acceptable approximation of the measured
DSC thermal analysis: The normalized DSC curve for the pyrolysis of
the EFB briquette is presented in Fig. 2.
|| DSC curves of the pyrolysis of the EFB briquette
|| Properties of EFB briquette
|ad: Air-dried basis, d: Dry basis, E: Experimental, C: Calculated
The graph only presents the pyrolysis reaction profile of the EFB from 30 to
450°C as no visible mass loss was observed beyond this end temperature.
From the DSC curves, it can be deduced the pyrolysis process occurs in stages
as indicated by the multiple DSC peaks observed in Fig. 2.
Studies by Stenseng et al. (2001); He
et al. (2006); Basu (2010) showed that pyrolysis
occurs in four stages namely:
||Initial stage (100-300°C) for heating of biomass
||Intermediate stage (200-600°C) for biomass degradation and char aggregation
||Final stage (300°C>) for secondary cracking of volatiles into char
and non-condensable gases
However, there are no distinct boundaries between these processes during biomass
(Basu, 2010) pyrolysis.
In addition to heating rate and residence time, temperature plays an important
role in the biomass pyrolysis. During pyrolysis the biomass fuel is heated to
a maximum (peak) temperature known as the pyrolysis temperature, an important
parameter that influences the composition and yield of the pyrolysis product
Table 2 presents data on the onset, peak and burnout temperature
of the different stages of the pyrolysis of EFB briquette during DSC thermal
analysis. The drying stage of the pyrolysis process is due to the moisture content
of the EFB briquette as presented in Table 1. The onset of
drying was observed at 58°C however moisture removal was completed at 140°C.
During the second stage heating of the biomass (140-220°C) no peaks were
observed during the process indicating there is no significant weight loss in
the briquette during this stage of pyrolysis.
However, during the degradation process (220-330°C), three endothermic
peaks where observed during heating. This may either be due to non-inform distribution
of fuel particles of different sizes observed in the sample or the effect of
sample weight on the DSC analysis as size and distribution of fuel particles
can influence heat and mass transfer during pyrolysis.
The thermal decomposition of EFB briquettes fuel particles began at 220°C
(with a maximum mass loss rate at 260°C) which is in agreement with the
findings of Yang et al. (2004) for EFB fiber
(raw material for making EFB briquettes).
|| Temperature profile of EFB briquette pyrolysis
The degradation of fuel particles in the temperature range (220-330°C)
can be attributed to the decomposition of hemicellulose and cellulose (Yang
et al., 2004; Basu, 2010). A single endothermic
peak was observed for the heating and aggregation of char formed during the
pyrolysis process. The decomposition of lignin is the main process occurring
during this final stage of pyrolysis (Basu, 2010). The
onset of char aggregation began at 328°C with a characteristic peak at 344°C.
The temperature of the char aggregation of EFB briquette is the highest temperature
achieved during the pyrolysis process and is therefore the pyrolysis peak temperature
of the fuel.
From the DSC analysis, the calorific enthalpy and specific heat capacity of
the fuel was deduced. Mathematically, this is expressed as (Brown,
where, Cp is the specific heat capacity of the fuel which can be
calculated from the calorific enthalpy ΔH of the fuel. From the MS EXCEL
calculations and analysis, the value of ΔH = 1080 J g-1. The
calculated Cp = 1397 J kg-1 K-1. It should be noted that
the value of calorific requirement was calculated based on the initial weight
of the briquette fuel. According to (He et al.,
2006) the heat required for drying the sample is an integral part of the
calorific requirement of biomass pyrolysis.
Fourier transform infra-red spectroscopy (FTIR): The typical products
of biomass pyrolysis are gases, liquids and solids depending on the heating
rate, temperature and residence time as represented in Eq. 5
The elemental and functional group composition of the fuel was analyzed using
FTIR spectroscopy. According to the study by Bassilakis
et al. (2001), the distribution of elements and functional groups
in the fuel can be a vital tool for predicting the distribution and composition
of the pyrolysis products. The FTIR spectra for the EFB briquette fuel is presented
in Fig. 3.
The broad O-H stretching vibrations between 3200 and 3400 cm-1 and
1050 and 1150 cm-1 indicate the presence of alcohols.
|| FTIR spectra of EFB briquette
The medium intensity band observed in 2368 cm-1 may be due to nitrile
C-N functional group, possibly indicating the presence of nitrogen in the elemental
composition of the fuel. However, this can only be confirmed by a detailed ultimate
analysis. The FTIR spectraalso indicated two bands of strong intensity in the
region 2800 and 3000 cm-1 typical of C-H stretching vibrations found
in CH3 and CH2 and the C-H deformation vibrations usually
observed between 1350 and 1475 cm-1 for alkenes. The broad intensity
band between 1600 and 1750 cm-1 indicates the presence of C = O stretching
vibrations typical of ketones and aldehydes. In addition the bands observed
between 1000 and 1300 cm-1 may also be due to the presence of ether
groups. The weak absorption bands observed between 600 and 900 cm-1
of the finger print region could not be assigned to specific functional groups
or elements. From the FTIR analysis of the fuel, the following gases as H2,
CO, CO2, CH4, CmHn
can be reasonably predicted for the pyrolysis of the fuel analyzed.
SEM analysis: Figure 4 presents the high resolution
SEM micrographs of EFB briquette at a magnification of 50x and 100x. This was
carried out to analyze the surface structure, composition and average particle
size distribution of the fuel before pyrolysis.
After grinding, the fuel particles were sieved using 800 micron Retsch sieve
to obtain particles less than 0.8 mm. However, the surface and particle size
distribution analysis using SEM micrographs indicated the presence of a combination
of spherical, cylindrical shaped agglomerates, fibers and asymmetrically dispersed
fuel particles ranging in size from 98 to 318 μm. The fuel particles were
grouped in multiples of 50 from 0 to 350 μm as shown in Table
|| SEM micrographs of EFB briquette at (a) 50x and (b) 100x
|| Particle size distribution of EFB briquette
From the SEM micrograph (magnificationx50) it was observed that 57% of the
fuel surface comprised particles in the 151-250 μm range, 14% of the particles
were greater than 251 μm and 7% below 100 μm.
The presence of agglomerated fuel particles may be due to the influence of
the briquette binder added during briquette manufacture or the high lignin content
~22% is found in EFB fiber (Saka, 2005). It is generally
accepted that particle size plays an important role in heat transfer during
pyrolysis. Consequently, small sized fuel particles usually characterized by
large surface areas are heated faster than large sized particles. This is corroborated
by Di Blasi (1996) whose findings showed that gas yield
and composition are influenced by heating rate of biomass particles.
Lv et al. (2004) showed increased gas yield,
heating value, carbon conversion efficiency for smaller sized fuel particles.
Conversely, the multiple peaks observed in the DSC can be explained by the irregular
distribution of fuel particles of varying sizes resulting in a non-uniform heating
profile during pyrolysis.
The HHV, DSC analysis, SEM microscopy of the EFB briquette was carried out.
The specific heat and the calorific requirement for EFB briquette pyrolysis
was calculated from DSC analysis. It was observed that 57% of the surface of
the fuel consisted of particles in the 151-250 μm range. The presence of
these large particles is a limiting factor for heat and mass transfer during
pyrolysis. FTIR analysis was used to predict the pyrolysis gas products. The
fuel properties observed indicates that the EFB briquette can be utilized as
a fuel for biomass pyrolysis.
The financial support of the GUP Grant, VOT No. 02J94 from the Ministry of
Higher Education (MOHE), Energy Research Alliance (ERA) and UniversitiTeknologi
Malaysia (UTM) and the assistance of the Research Management Centre (RMC) is
1: Abdullah, N., H. Gerhauser and F. Sulaiman, 2010. Fast pyrolysis of empty fruit bunches. Fuel, 89: 2166-2169.
2: Affendy, H., M. Aminuddin, M. Azmy, M.A. Amizi, K. Assis and A.T. Tamer, 2011. Effect of organic fertilizers application to the growth of Orthosiphon stamineus Benth. Intercropped with Hevea brasiliensis Willd. and Durio zibethinus Murr. Int. J. Agric. Res., 6: 180-187.
CrossRef | Direct Link |
3: Baharuddin, A.S., M. Wakisaka, Y. Shirai, S. Abd-Aziz, N.A. Abdul-Rahman and M.A. Hassan, 2009. Co-composting of empty fruit bunches and partially treated palm oil mill effluents in pilot scale. Int. J. Agric. Res., 4: 69-78.
CrossRef | Direct Link |
4: Bari, M.N., M.Z. Alam, S.A. Muyibi, P. Jamal and A.A. Mamun, 2010. Effect of particle size on production of citric acid from oil palm empty fruit bunches as new substrate by wild Aspergillus niger. J. Applied Sci., 10: 2648-2652.
CrossRef | Direct Link |
5: Bassilakis, R., R.M. Carangelo and M.A. Wojtowicz, 2001. TG-FTIR analysis of biomass pyrolysis. Fuel, 80: 1765-1786.
6: Basu, P., 2010. Biomass Gasification and Pyrolysis: Practical Design and Theory. 1st Edn., Academic Press, New York, USA., ISBN-13: 9780123749888, Pages: 376.
7: Bhattacharya, S.C. and R.M. Shrestha, 1990. Biotechnology and Economics. RFRIC Asian Institute of Technology (AIT), Bangkok, Thailand, ISBN: 974-888201-441.
8: Bhattacharya, S.C., R.M. Shrestha, P. Wongvicha and S. Ngamkajornvivat, 1989. A survey of uncarbonized briquettes and biocoal markets in Thailand. RERIC Int. J., 11: 17-28.
Direct Link |
9: Brown, M.E., 1938. Introduction to Thermal Analysis: Techniques and Applications. Chapman and Hall, London, UK.
10: Chen, G., J. Andries, Z. Luo and H. Spliethoff, 2003. Biomass pyrolysis/gasification for product gas production: The overall investigation of parametric effects. J. Energ Convers. Manage., 44: 1875-1884.
11: De Souza, S., S. Pacca, M.T. De Avila and J.L.B. Borges, 2010. Greenhouse gas emissions and energy balance of palm oil biofuel. Renewable Energy, 35: 2552-2561.
12: Demirbas, A., 2001. Biomass resource facilities and biomass conversion processing for fuels and chemicals. Energy Conversion Manage., 42: 1357-1378.
13: Demirbas, A., 1997. Calculation of higher heating value of biomass fuel. Fuel, 76: 431-434.
14: Di Blasi, C., 1996. Kinetic and heat transfer control in the slow and flash pyrolysis of solids. Ind. Eng. Chem. Res., 35: 37-46.
15: Di Blasi, C., G. Signorelli, C.D. Russo and G. Rea, 1999. Product distribution from pyrolysis of wood and agricultural residues. Ind. Eng. Chem. Res., 38: 2216-2224.
16: He, F., W. Yi and X. Bai, 2006. Investigation on caloric requirement of biomass pyrolysis using TG-DSC analyser. Energy Convers. Manage., 47: 2461-2469.
17: Grover, P.D. and S.K. Mishra, 1996. Biomass briquetting: Technology and practices. FAO Report, Food and Agriculture Organization of the United Nations, Bangkok, Thailand.
18: Jalan, R.K. and V.K. Srivastava, 1999. Studies on pyrolysis of a single biomass cylindrical pellet-kinetic and heat transfer effects. Energy Conv. Manage, 40: 467-494.
CrossRef | Direct Link |
19: Kassim, M.A., L.S. Kheang, N.A. Bakar, A.A. Aziz and R.M. Som, 2011. Biothanol production from enzymatically saccharified empty fruit bunches hydrolysate using Saccharomyces cerevisiae. Res. J. Environ. Sci., 5: 573-586.
20: Kelly-Yong, T.L., S. Lim and K.T. Lee, 2011. Gasification of oil palm empty fruit bunch fibers in hot compressed water for synthesis gas production. J. Applied Sci., 11: 3563-3570.
CrossRef | Direct Link |
21: Lahijani, P. and Z.A. Zainal, 2011. Gasification of palm empty fruit bunch in a bubbling fluidized bed: A performance and agglomeration study. Bioresour. Technol., 102: 2068-2076.
CrossRef | PubMed |
22: Lappas, A.A., M.C. Samolada, D.K. Iatridis, S.S. Voutetakis and I.A. Vasalos, 2002. Biomass pyrolysis in a circulating fluid bed reactor for the production of fuels and chemicals. Fuel, 81: 2087-2095.
23: Li, S., S. Xu, S. Liu, C. Yang and Q. Lu, 2004. Fast pyrolysis of biomass in free-fall reactor for hydrogen-rich gas. Fuel Process. Technol., 85: 1201-1211.
24: Liliedahl, T. and K. Sjostrom, 1998. Heat transfer controlled pyrolysis kinetics of a biomass slab, rod or sphere. Biomass and Bioenergy, 15: 503-509.
CrossRef | Direct Link |
25: Lv, P.M., Z.H. Xiong, J. Chang, C.Z. Wu, Y. Chen and J.X. Zhu, 2004. An experimental study on biomass air-steam gasification in a fluidized bed. Bioresour. Technol., 95: 95-101.
26: Mae, K., I. Hasegawa, N. Sakai and K. Miura, 2000. A new conversion method for recovering valuable chemicals from oil palm shell wastes utilizing liquid-phase oxidation with H2O2 under milled conditions. Energy Fuels, 14: 1212-1218.
Direct Link |
27: Mahlia, T.M.I., M.Z. Abdulmuin, T.M.I. Alamsyah and D. Mukhlishien, 2003. Dynamic modelling and simulation of a palm wastes boiler. Renewable Energy, 28: 1235-1256.
28: McKendry, P., 2002. Energy production from biomass (part 2): Conversion technologies. Bioresour. Technol., 83: 47-54.
29: Mohammed, M.A.A., A. Salmiaton, W.A.K.G. Wan Azlina, M.S.M. Amran, A. Fakhrul-Razi and Y.H. Taufiq-Yap, 2005. Hydrogen rich gas from oil palm biomass as a potential source of renewable energy in Malaysia. Renewable Sustainable Energy Rev., 15: 1258-1270.
30: Rath, J., G. Steiner, M.G. Wolfinger and G. Staudinger, 2002. Tar cracking from fast pyrolysis of large beech wood particles. Analytical Application Pyrolysis, 62: 83-92.
31: Rath, J., M.G. Wolfinger, G. Steiner, G. Krammer, F. Barontini and V. Cozzani, 2003. Heat of wood pyrolysis. Fuel, 82: 81-91.
32: Saka, S., 2005. Whole efficient utilization of oil palm to value-added products. Proceedings of the JSPS-VCC Natural Resources and Energy Environment Seminar, September 7-8, 2004, Kyoto, Japan -.
33: Sharma, A. and T.R. Rao, 1998. Analysis of an annular finned pyrolyser. Energy Convers. Manage., 39: 985-997.
34: Stenseng, M., A. Jensen and K. Dam-Johansen, 2001. Investigation of biomass pyrolysis by thermogravimetric analysis and differential scanning calorimetry. J. Anal. Applied Pyrolysis, 58-59: 765-780.
35: Sulaiman, F. and N. Abdullah, 2011. Optimum conditions for maximising pyrolysis liquids of oil palm empty fruit bunches. Energy, 36: 2352-2359.
36: Sung, C.T.B., G.K. Joo and K.N. Kamarudin, 2010. Physical changes to oil palm Empty Fruit Bunches (EFB) and EFB Mat (Ecomat) during their decomposition in the field. Pertanika J. Trop. Agric. Sci., 33: 39-44.
Direct Link |
37: Wahid, M.B., S.N.A. Abdullah and I.E. Henson, 2004. Oil palm: Achievements and potential. Proceedings of the 4th International Crop Science Congress, September 26-October 1, 2004, Brisbane, Australia, pp: 1-13.
38: Yang, H.P., R. Yan, H.P. Chen, D.H. Lee, D.T. Liang and C. Zheng, 2006. Pyrolysis of palm oil wastes for enhanced production of hydrogen rich gases. Fuel Proc. Technol., 87: 935-942.
39: Yang, H., R. Yan, T. Chin, D.T. Liang, H. Chen and C. Zheng, 2004. Thermogravimetric analysis-Fourier transform infrared analysis of palm oil waste pyrolysis. Energy Fuels, 18: 1814-1821.
CrossRef | Direct Link |
40: Yusoff, S., 2006. Renewable energy from palm oil-innovation on effective utilization of waste. J. Cleaner Prod., 14: 87-93.
CrossRef | Direct Link |