Neonufac a Combustion Engines and Propulsion Systems Laboratory, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Bandung 40132, Indonesia b Division of Mecha
Trang 1Full Length Article
Experimental investigation of the effects of cycloparaffins and aromatics
on the sooting tendency and the freezing point of soap-derived
biokerosene and normal paraffins
Long H Duonga,d, Osamu Fujitab,⇑, Iman K Reksowardojoa, Tatang H Soerawidjajac, Godlief F Neonufac
a
Combustion Engines and Propulsion Systems Laboratory, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Bandung 40132, Indonesia
b
Division of Mechanical and Space Engineering, Hokkaido University, Sapporo 060-8628, Japan
c
Department of Chemical Engineering, Faculty of Industrial Technology, Institut Teknologi Bandung, Bandung 40132, Indonesia
d
Department of Automotive Engineering, Faculty of Transportation Engineering, Ho Chi Minh City University of Technology, Ho Chi Minh City 70350, Viet Nam
a r t i c l e i n f o
Article history:
Received 1 May 2016
Received in revised form 10 August 2016
Accepted 12 August 2016
Available online 19 August 2016
Keywords:
Soap-derived biokerosene
Sooting tendency
Freezing point
Normal paraffins
Cycloparaffins
Aromatics
a b s t r a c t
The effects of cycloparaffin and aromatic hydrocarbons when blended with soap-derived biokerosene (SBK) and normal paraffins (n-paraffins) on the sooting tendency and the freezing point are quantified
to determine a method for improving the properties of SBK and n-paraffin fuels In this study, SBK was derived from the saponification and dercarboxylation of coconut oil, and consists predominantly of n-paraffins with carbon chain lengths from C7 to C17 Dodecane, butylcyclohexane and butylbenzene were chosen as surrogate components for n-paraffins in SBK, cycloparaffins and aromatics, respectively The total soot volume was measured from the light extinction at ambient conditions in a wick-fed lam-inar diffusion flame The measured smoke point of the fuel was correlated with the required sooting ten-dency according to the jet fuel standard The freezing point was measured using the JIS K2276 test method The results show that butylcyclohexane affects the sooting tendency much lesser than butylben-zene when blended with SBK or dodecane In contrast, butylcyclohexane decreases the freezing point more, as compared to butylbenzene, when blended with dodecane Butylcyclohexane and butylbenzene have a similar trend of effect on the freezing point when blended with SBK or dodecane Blending SBK or dodecane with butylcyclohexane matches the requirements of both smoke point and freezing point for jet fuel specified by ASTM D1655 Conversely, blending SBK or dodecane with butylbenzene does not meet these requirements Therefore, given the tradeoff between sooting tendency and freezing point, cycloparaffins are considered more promising than aromatics for blending with SBK or n-paraffin fuels
Ó 2016 Elsevier Ltd All rights reserved
1 Introduction
Air transportation in the modern world is rapidly growing in
popularity due to an increasing demand for business and leisure
travel As a result, the worldwide commercial jet fleet is expected
average growth rate of world traffic is 4.6% for the next 20 years
subse-quent exhaust gas emissions will increase Currently, jet fuel prices
fluctuate as they depend not only on the availability of crude oil
obtained from fossil fuels but also on many societal, economical,
and, especially, political factors These fluctuations in the price of
jet fuels create many serious problems for airline companies,
because the fuel cost represents up to 30% of an airline’s operating
is currently responsible for approximately 3% of the total global greenhouse gas (GHG) emissions Although this value represents
a small fraction of the total GHG emissions, aircraft emissions con-tinue to increase and are expected to constitute nearly 5%, even
effort to reduce GHG emissions and meet the European environ-mental goals for 2020 and beyond, the European Union has
legislation, all aircrafts flying within or into the European Eco-nomic Area must either decrease their GHG emissions or purchase
To reduce GHG emissions, some efforts have been applied such as improvement of fuel consumption efficiency by increasing engine
http://dx.doi.org/10.1016/j.fuel.2016.08.050
0016-2361/Ó 2016 Elsevier Ltd All rights reserved.
⇑ Corresponding author at: Division of Mechanical and Space Engineering,
Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan.
E-mail address: ofujita@eng.hokudai.ac.jp (O Fujita).
Fuel
j o u r n a l h o m e p a g e : w w w e l s e v i e r c o m / l o c a t e / f u e l
Trang 2efficiency, aircraft structure designing, and optimizing air traffic
management Along with those methods, using biofuel is
increas-ingly considered by airline companies and governments because
biofuel is a renewable resource and significantly reduces the
reduce the pollutant emissions, such as carbon monoxide,
unburned hydrocarbon, nitrogen oxides, and soot emission, from
been approved by the American Society for Testing Materials
(ASTM) for blending with conventional jet fuel to use in aviation
gas turbine engines These include synthesized paraffinic kerosine
from hydroprocessed esters and fatty acids, Fischer–Tropsch
hydroprocessed synthesized paraffinic kerosine from biomass,
thesized iso-paraffins from hydroprocessed fermented sugars,
syn-thesized kerosene with aromatics derived by alkylation of light
aromatics from non-petroleum resources, and alcohol-to-jet
syn-thesized paraffinic kerosene The detailed requirements of their
Tropical countries, in general, and Indonesia, in particular, are
the ideal location for developing ground-used and aviation biofuel
because of the abundance of plant oil resources, the vast rural
areas, and the low labor cost Moreover, the Indonesian
govern-ment approved a plan to use up to 2%, 3%, and 5% by volume of
avi-ation biofuel during flights by 2016, 2018, and 2025, respectively
avi-ation biofuel due to the limitavi-ation in technology and investment
Therefore, production of aviation biofuel based on simple
tech-nologies at a low cost, and leveraging the available national
advan-tages is a foreseeable solution The production of soap-derived
biokerosene (SBK) meets the above criteria, because it primarily
produc-tion comprises of two main steps: (1) the saponificaproduc-tion process,
through which plant oil fatty acids and triglycerides are converted
into basic-soap and (2) the subsequent thermal decarboxylation
the basic-soap is transformed into normal-paraffins (n-paraffins)
Thereby, SBK production is simpler and less energy consumption
than the hydtrotreating processes, which are reacted at high
tem-perature and pressure with the presence of catalyst and hydrogen,
fuel used in aviation gas turbine engines is required to have a very
into branched paraffins (iso-paraffins), which have a significantly
lower freezing point Besides, in order to improve the other
prop-erties of aviation biofuels, especially, distillation, the cracking
pro-cess is also implemented to break the long carbon chain that
exceeds the jet range into shorter chain length paraffins A typical
production process of this type of aviation biofuel is presented in
appro-priate solutions based on the feedstock conditions, the available
technology, and the socioeconomic situation in Indonesia is
encouraged Thereby, to avoid the cracking process in the SBK
pro-duction, the plant oils that have carbon chain length of fatty acids
Besides, mixing SBK with other bio-derived components that have
low freezing points is a potential alternative to the isomerization
process to reduce the freezing point of the biofuel Mixed biofuels with products of different production processes is also promising
feed-stock and suitable facilities to produce biofuels, thus maximizing the national potential to develop a sustainable aviation biofuel in each country Currently, there are many approaches to produce aromatics or cycloparaffins (naphthenes) from bio-feedstocks
hydrogenation of aromatics, their price may be higher than that
feed-stocks are established in the future, then it would be simpler and cheaper to produce cycloparaffins One promising production pro-cess for producing cycloparaffins in Indonesia is the hydrogenation
of turpentine oil obtained from pine tree (Pinus merkusii), as
a method for producing iso-paraffins, the same method can theo-retically be used to produce cycloparaffins
Cycloparaffins and aromatics can be mixed with SBK to decrease its freezing point since they have a lower freezing point than that of n-paraffins with same carbon number However, they exhibit a very different sooting tendency The jet fuel standard (ASTM D1655) specifies that the maximum volume fraction of aro-matics present in commercial jet fuels such as Jet A, Jet A-1, and Jet
Soot formation in a gas turbine combustor is problematic because
it generates high radiation heat and deposits, which can damage the combustion chamber or the turbine blade, thus reducing the
emit-ted with the exhaust gas from a gas turbine engine are dangerous
tendency plays an important role for evaluating a potential compo-nent to mix with SBK
This research focuses on comparing the effects of cycloparaffins and aromatics on the sooting tendency and the freezing point when mixed with SBK and n-paraffin fuels Butylcyclohexane and butylbenzene were chosen as the surrogate components for cycloparaffin and aromatic hydrocarbons, respectively Because dodecane has the same carbon number with the average SBK
in SBK and jet range n-paraffin fuels Based on the results of this work, the potential of cycloparaffins and aromatics for mixing with SBK and n-paraffin fuels is assessed with regard to the tradeoffs between the sooting tendency and the decrease of the freezing point
2 Experimental setup and procedures 2.1 Total soot volume of laminar diffusion wick-fed flame and smoke point measurement
The experimental setup used for determining the total soot
soot volume of the laminar diffusion wick-fed flame was deter-mined by employing a light extinction method As shown in
tubes (outer tube diameter = 0.8 cm, inner tube diameter = 0.5 cm)
Normal paraffins
Basic Soaps
Coconut Oil
Saponification process
Decarboxylation process
Trang 3socket and fuel tank, respectively By rotating the wick-height
con-trol nut, the fuel tank could shift up or down inside the fixed socket
to expose more or less of the wick, respectively, thus controlling
the flame height ASTM specification cotton wick was used to
install to the fuel tank A 30-cm-long, and 9-cm-outer-diameter
glass tube covered the burner as a chimney Dry air was supplied
to the chimney at a constant flow rate of 30 L/min, or an equivalent
air velocity of 7.86 cm/s, for all measurements Three aluminum
honeycombs were used to generate laminar flow inside the
chim-ney To refill the fuel and measure the fuel consumption, a
1-mm-inner-diameter clear glass tube was connected to the fuel tank
through a silicon pipe If kept parallel and vertical, the level of
the fuel in the fuel tank remained the same as that in the fuel refill
tube The fuel mass was measured with a Shimadzu UX2200H
dig-ital balance at a resolution of 0.01 g The duration of burning was
timed with a stopwatch The approximate flame height was
deter-mined with a ruler and then precisely deterdeter-mined by analyzing the
flame image recorded by a Canon VIXIA HF S21 camera To derive
the total soot volume, a Panasonic HDC-TM750 camera with an
interference filter lens was used This filter lens only allowed light
with 540 nm wavelength from a backlight system The recorded
backlight image with and without the flame was used as input to
a MATLAB program to calculate the total soot volume of the flame
soot volume fraction in the Rayleigh wavelength range (particle
to be negligible; this practice was commonly used by other studies
fv¼ k ln
I
0
6pLImðmðm221Þþ2Þ
ð1Þ
path length, and m is the optical refractive index of the soot
parti-cles In this study, the optical refractive index of the soot particles
was m = 1.57–0.56i, in accordance with many previous studies
Vs¼
ZH f
0
Z R 0
The smoke point of the fuel, which is defined as the maximum height (in millimeters) of a smoke-free laminar diffusion flame of
studies proposed a method of using the relationship between the mass fuel consumption and the flame height to obtain a more accu-rate smoke point of the fuel, as compared to the direct visual
system in this work has some slight modifications compared with that of these studies Instead of placing the balance under the fuel tank to determine the fuel mass, a constant volume of fuel mea-sured based of its mass just before filling to the fuel tank was used for determining the duration of the burn Theoretically, because the temperature of the fuel tank was nearly same throughout a measurement, the same volume of fuel has the same mass Two standard samples proposed by ASTM D1322 mixed with toluene and iso-octane (2,2,4-trimethylpentane) with volume fractions of 40/60 and 10/90, respectively, were measured to compare with the smoke point given in ASTM D1322 The results indicated that the smoke points in this study for the 40/60 and 10/90 samples dif-fered from that of the ASTM D1322 standard by 2.04% (15 mm ver-sus 14.7 mm) and 0.66% (30.0 mm verver-sus 30.2 mm), respectively Therefore, this method was considered reliable for measuring the smoke point of other fuel samples
In order to investigate the sooting tendency, several mixtures of SBK/butylcyclohexane, and SBK/butylbenzene were used to mea-sure on the total soot volume and the smoke point Because the composition of SBK consists predominantly of n-paraffins that exhibit a carbon chain length within the jet range, some typical n-paraffins in this range including decane, dodecane, and hexade-cane were applied to measure on the total soot volume SBK was produced in-house from coconut oil The composition of SBK was analyzed by using gas chromatograph equipment named Shimadzu
2010 The weight fraction of hydrocarbon types in SBK are listed in
Sigma-Aldrich Corp and Tokyo Chemical Industry Co., Ltd The properties
2.2 Freezing point measurement The freezing points of the fuels were measured by JFE Techno-Research Corporation in Japan using the JIS K2276 test method,
Table 1 Composition of soap-derived biokerosene.
Hydrocarbon type wt.%
Normal paraffins 67.19 Olefins 21.77 Aromatics 9.06 Branched paraffins 1.93
Wick height control
Fuel refill
& level Valve
Digital
Camera
Dry air
Flow meter
Chimney
Light source
Fuel tank
Burner
Fuel tank socket
Interference
filter lens
Honeycomb
Fig 3 Schematic of the experimental setup.
(n + iso) paraffins Normal
paraffins Plant oils,
animal fats
Hydrotreating process
Isomerization &
cracking process
Fig 2 Hydroprocessed esters and fatty acids production process [12,30,31]
Trang 4points of several mixtures of SBK/butylcyclohexane, dodecane/
butylcyclohexane, and dodecane/butylbenzene were measured
3 Results and discussion
3.1 Total soot volume
vol-ume compared to the n-paraffins in the range of C10–C16 This is
due to the fraction of olefins, especially, aromatics present in SBK
composition includes unsaturated hydrocarbons such as olefins,
which are formed from the unsaturated fatty acid chains in
coconut oil The olefins have a greater sooting tendency than the
produces greater soot mainly due to its aromatic fraction In
decar-boxylation, some fractions of the unsaturated hydrocarbon bonds
Aromatics are known to have a very high soot formation
The total soot volume as measured for a mixture of 90% dodecane
and 10% butylbenzene (DOD90BBZ10) by volume Dodecane was
selected to represent the n-paraffins in SBK because it is the closest
with the average molecule of SBK By volume, 10% butylbenzene
was mixed with dodecane since it represents the approximate
total soot volume of SBK is very close to that of DOD90BBZ10 at several flame heights
soot volume than SBK while butylbenzene has the highest total soot volume Therefore, blending butylcyclohexane with SBK pro-duces less total soot volume; however, the difference is very small,
increases the total soot volume when blended with SBK, as shown
greater formation of soot compared to butylcyclohexane when they are mixed with SBK To obtain a clearer quantitative compar-ison regarding to the jet fuel specification, the smoke point of these blends was measured and presented in the following section 3.2 Smoke point
butylbenzene on the smoke point when blended with SBK Butyl-cyclohexane slightly increases the smoke point because its smoke point is a little higher compared with that of SBK (55.5 mm versus 52.5 mm), whereas, butylbenzene strongly decreases the smoke point of these blends because it has a significantly lower smoke point than SBK (8.5 mm versus 52.5 mm) The lower smoke point indicates a greater tendency to form soot
The distribution of carbon chains in aviation biofuel simulates that of conventional jet fuel as much as possible Thus, the carbon chain length of the current aviation biofuels commonly lay within
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
3)
Flame height (mm)
DEC DOD HEX BCH SBK BBZ DOD90BBZ10
Fig 4 Total soot volume as a function of flame height of SBK, pure hydrocarbons
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
0 5 10 15 20 25 30 35 40 45 50 55
3)
Flame height (mm)
SBK SBK75BCH25 SBK50BCH50 BCH
Fig 5 Total soot volume vs flame height of the mixtures: SBK (100% SBK); SBK75BCH25 (75% SBK + 25% butylcyclohexane); SBK50BCH50 (50% SBK + 50%
Table 2
Properties and information of soap-derived biokerosene (SBK), and hydrocarbon compounds.
Fuel Code Molecular formula CAS no Purity (%) Density (kg/m 3
) M.W a
F.P b (°C) S.P c
(mm) Soap-derived biokerosene SBK C7-C17 810 160.64 d
0.5 52.5 Decane DEC C10H22 124-18-5 >99.0 730 142.28 30 99.5 Dodecane DOD C12H26 112-40-3 >99.0 750 170.33 9.6 94
Hexadecane HEX C16H34 544-76-3 >99.0 774 226.44 18 87.5 Butylcyclohexane BCH C10H20 1678-93-9 >99.0 800 140.27 78 55.5 Butylbenzene BBZ C10H14 104-51-8 >99.0 860 134.22 88 8.5
2,2,4-Trimethylpentane C8H18 540-84-1 >99.0 692 114.23 107 43
a M.W: molecular weight.
b F.P: freezing point.
c
S.P: smoke point.
d
Obtaining by estimation method.
Trang 5total soot volume inFig 4shows that the differences in the total
soot volume among the n-paraffins with carbon chain length from
C10 to C16 are insignificant Dodecane has the same carbon
num-ber with the average carbon chain length of jet fuel Thus, it is a
good candidate for a surrogate component of biofuel for aviation
alternative fuels containing of n-paraffins, as well as n-paraffin
hydrocarbon class in the jet fuel On the other hand, regarding
the production process of SBK, n-paraffins in SBK are expect to
have a carbon chain length shorter by one than that of the fatty
acids in coconut oil; the latter lays almost within the jet range
experi-mental results on dodecane are not only useful for studies on fuels
that consist of n-paraffins in the jet range, but also provide a good
reference for comparison with SBK to confirm its quality and
butylbenzene decrease the smoke point when blended with dode-cane However, butylbenzene has a much greater effect on the
the volume fraction of butylcyclohexane blended with SBK and dodecane could reach up to 100%, satisfying the requirement on the smoke point of the jet fuel specified by ASTM D1655 (min
25 mm) In contrast, the volume fraction of butylbenzene to blend with SBK and dodecane is limited by a certain amount that is can
butylcyclohex-ane or butylbenzene is blended with SBK, the smoke points of the mixtures are significantly lower than those of their mixtures with dodecane, when using the same volume fractions This is because the smoke point of SBK (52.5 mm) is lower than that of dodecane (94.0 mm) The lower smoke point of SBK is due to the
with volume fraction of 90/10 exhibits a smoke point very close
to that of SBK (52.5 mm) This observation is consistent with the
of DOD90BBZ10 is suitable as a surrogate for SBK while dodecane can be used as a surrogate component for the jet range n-paraffins to evaluate the sooting tendency
butylcyclohexane or butylbenzene and the reversed smoke point
of the fuel mixtures This correlation is consistent with the ones
LSP;mix¼ X ti
LSP;i
ð3Þ
the smoke point of the component i and the volume fraction of the component i, respectively Van Treuren proposed this correlation for
Table 3
Fatty acids profile of coconut oil.
Oil Fatty acids composition (wt.%)
8:0 10:0 12:0 14:0 16:0 18:0 18:1 18:2 18:3 Coconut oil [45] 4.9–8.7 4.3–6.5 42.3–53.1 17.2–19.8 7.4–10.8 2.0–3.4 4.7–8.9 0.7–3.5 0–0.2 Coconut oil [46] 4.6–9.5 4.5–9.7 44–51 13–20.6 7.5–10.5 1–3.5 5–8.2 1–2.6 0–0.2
0 10 20 30 40 50 60 70 80 90 100
Fraction of butylcyclohexane or butylbenzene
(vol.%)
DOD/BCH DOD/BBZ ASTM D1655 min
Fig 8 Smoke point as a function of the butylcyclohexane and butylbenzene content in the mixture with dodecane.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0 5 10 15 20 25 30 35 40 45 50 55
3)
Flame height (mm)
SBK SBK75BBZ25 SBK50BBZ50 BBZ
Fig 6 Total soot volume vs flame height of the mixtures: SBK (100% SBK);
SBK75BBZ25 (75% SBK + 25% butylbenzene); SBK50BBZ50 (50% SBK + 50%
butyl-benzene); BBZ100 (100% butylbenzene).
0
10
20
30
40
50
60
Fraction of butylcyclohexane or butylbenzene
(vol%.)
SBK/BCH SBK/BBZ ASTM D1655 min
Fig 7 Smoke point as a function of the butylcyclohexane and butylbenzene
content in the mixture with SBK.
Trang 6the mixture of fossil-derived liquid fuels[52], then Li and
parameter that equals to a constant multiply by the inversed smoke
point was proposed as the first definition on the sooting tendency
tendency of hydrocarbon fuels by using this parameter remained
some shortcomings because it did not take into account the effect
of fuel molecular size on flame height To consume a unit volume
of fuel, the fuel with higher molecular weight needs more volume
of oxygen to diffuse into the flame, thus increasing the flame height
hydrocarbon fuels to resolve this issue Recently, Barrientos et al
to extend the same concept to oxygenated fuels Currently, TSI
and OESI are more commonly used than the inversed smoke point
for evaluating and comparing on sooting tendency of the fuels
spec-ified by standard for jet fuel Therefore, to find the maximum
allow-able volume fraction of butylcyclohexane or butylbenzene to blend
with SBK or dodecane in order to satisfy the requirement on the
smoke point of jet fuel, the correlation on inversed smoke point of
28% are the maximum allowable volumes of butylbenzene to blend
with SBK and dodecane, respectively, in order to satisfy the
mini-mum smoke point required for jet fuel (25 mm) However, because
SBK contains some fractions of aromatics, it should be noted that
the maximum allowable volume fraction of aromatics in jet fuel is
25% according to ASTM D1655 This figure also indicates that no
limitations exist in the fraction of butylcyclohexane that hinder
its blending with SBK or dodecane to satisfy the smoke point
requirement of jet fuel
3.3 Freezing point
The freezing point is one of the most critical properties of jet
fuel ASTM D1655 requires that the maximum freezing point is
47 °C for Jet A1, which is the commercial jet fuel widely used
worldwide The n-paraffins, which have a carbon chain length
equal to the fatty acid chains in plant oils or animal fats, normally
acids present in almost all plant oils and animal fats have carbon
There-fore, to decrease the freezing point of these n-paraffins, further processing is required Two of the most typical such processes are cracking and isomerization However, these are both
cycloparaffins or aromatics may also reduce the freezing point
butylcyclohex-ane when blended with SBK and dodecbutylcyclohex-ane is almost similar The freezing point decreases with increasing volume fraction of butyl-cyclohexane in blend with SBK or dodecane The slightly lower freezing points of dodecane/butylcyclohexane blends are due to
the freezing point more when mixed with dodecane than
due to the improved solubility of the butylcyclohexane, as com-pared to butylbenzene, when blended with dodecane, since the
or dodecane can reduce the freezing point of the blend up to
47 °C, thus matching the freezing point required by ASTM D1655 for Jet A1 In contrast, because the maximum allowable vol-ume fraction of butylbenzene in a blend is limited to 25%, which is
mixed with dodecane, and definitely when blended with SBK
4 Conclusions The total soot volume, smoke point, and freezing point of SBK,
butylbenzene were measured in this study In addition, some n-paraffins with carbon number within the jet range, such as decane, dodecane, and hexadecane, were also examined with regard to their total soot volume to compare them with SBK The freezing point is a critical property of jet fuel and the most challenging requirement of aviation biofuel Blending SBK or n-paraffins fuel with cycloparaffin and aromatic hydrocarbons, which have low freezing points is a potential solution to reduce the freezing point of the fuel However, the requirement regarding
-100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10
Fraction of butylcyclohexane or butylbenzene
(vol.%)
SBK/BCH DOD/BCH DOD/BBZ ASTM D1655 max.
ASTM D1655 max vol frac.
Fig 10 Freezing point as a function of the butylcyclohexane and butylbenzene content in the mixture with SBK and dodecane.
y = -1E-05x + 0.019 R² = 0.94648
y = 0.001x + 0.0199
R² = 0.99964
y = 7E-05x + 0.0104 R² = 0.99299
y = 0.0011x + 0.0087 R² = 0.9986
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.11
0.12
0.13
0.14
-1)
Fraction of butylcyclohexane or butylbenzene
(vol.%)
SBK/BCH SBK/BBZ DOD/BCH DOD/BBZ ASTM D1655 min
Fig 9 Inversed smoke point as a function of the butylcyclohexane and
butylben-zene content in mixture with SBK and dodecane.
Trang 7the formation of soot might limit the fraction of these hydrocarbons
that can be mixed with SBK or n-paraffins This work was done to
assess this issue, and the following conclusions were reached:
(1) Butylcyclohexane and butylbenzene produce reverse effects
on the sooting tendency and the freezing point when
blended with SBK or dodecane Regarding the sooting
ten-dency, butylcyclohexane produces a significantly smaller
effect compared to butylbenzene In contrast,
butylcyclohex-ane decreases the freezing point more than butylbenzene
although the freezing point of butylcyclohexane is higher
than that of bultylbenzene
(2) SBK or dodecane can be blended with butylcyclohexane to
reduce the freezing point of the mixtures to meet the
requirements on both the smoke point and the freezing
point specified for jet fuel In contrast, because of the
requirements on the smoke point and/or the maximum
allowable volume fraction of aromatics, blending SBK or
dodecane with butylbenzene is infeasible to satisfy the
freezing point
(3) The differences in the total soot volume among n-paraffins
with carbon number range from C10 to C16 are insignificant
Therefore, the fuel that consists of n-paraffins in this carbon
number range, especially, when dominated by C12 can use
dodecane as a surrogate for evaluating the sooting tendency
SBK includes some fractions of olefins and aromatics, thus a
mixture of 90% dodecane and 10% butylbenzene by volume
is suitable as a surrogate of SBK to simulate the total soot
volume and the smoke point
Considering the tradeoff between the sooting tendency and the
decrease of the freezing point, cycloparaffins are better for
blend-ing with SBK or n-paraffins fuel as compared to aromatics
Acknowledgments
We gratefully acknowledge the ASEAN University Network
Southeast Asian Engineering Education Development Network
(AUN/SEED-Net) project of the Japan International Cooperation
Agency (JICA) for financial support OF is supported by Grant in
aid # 15K13878 for scientific research of Japan
References
[1] Boeing Current market outlook 2015–2034 Boeing commercial airplanes,
market analysis, P.O Box 3707, MC 21–28, Seattle, WA 98124–2207; 2015.
[2] Airbus Global market forecast 2014–2034 Airbus S.A.S 31707 Blagnac Celdex;
2014.
[3] International Air Transport Association IATA economic briefing: airline fuel
and labour cost share; February 2010.
[4] Intergovernmental Panel on Climate Change (IPCC) 1999 Aviation and the
global atmosphere; 2015 < http://www.grida.no/publications/other/ipcc_sr/?
src=/Climate/ipcc/aviation/index.html > [accessed 15.12.02].
[5] European Directive 2008/101/CE on Aviation Gas Emission.
[6] Pope J, Owen AD Emission trading schemes: potential revenue effects,
compliance costs and overall tax policy issues Energy Policy 2009;37
(11):595–603
[7] Deane P, Shea RO, Gallachoir BO Biofuels for aviation, rapid response energy
brief Insight; April 2015.
[8] International Air Transport Association IATA 2014 Report on alternative fuels.
Montreal–Geneva; December 2014.
[9] ASTM D7566 Standard specification for aviation turbine fuel containing
synthesized hydrocarbons American Society for Testing and Materials; 2016
[10] Rogelio SB, Fernando TZ, Felipe JHL Hydroconversion of triglycerides into
green liquid fuels In: Karame Iyad, editor Hydrogenation Mexico: InTech;
2012 p 187–216
[11] Klingshirn CD, DeWitt M, Striebich R, Anneken D, Shafer M Hydroprocessed
renewable jet fuel evaluation, performance, and emissions in a t63 turbine
engine J Eng Gas Turbines Power 2012;134:051506-1–6-8
[12] Rahmes TF, Kinder JD, Henry TM, Crenfeldt G, LeDuc GF, Zombanakis GP, et al.
Sustainable bio-derived synthetic paraffinic kerosene (Bio-SPK) jet fuel flights
integration, and operations conference Hilton Head, South Carolina 21–23 September 2009
[13] Blakey S, Rye L, Wilson CW Aviation gas turbine alternative fuels: a review Proc Combust Inst 2011;33:2863–85
[14] Speth RL, Rojo C, Malina R, Barrett SRH Black carbon emissions reductions from combustion of alternative jet fuels Atmos Environ 2015;105:37–42 [15] Badami M, Nuccio P, Pastrone D, Signoretto A Performance of a small-scale turbojet engine fed with traditional and alternative fuels Energy Convers Manage 2014;82:219–28
[16] Aviation fuels technical review ChevronTexaco Corporation; 2005 [17] The Coordinating Research Council, Inc., Handbook of aviation fuel properties In: Society of Automotive Engineers Publications Department 400 Commonwealth Drive Warrendale Pennsylvania 15096 3th ed.; 2004, p 1–6 [18] Gary JH, Handwerk GE Petroleum refining–technology and economics 4th
ed New York: Marcel Dekker; 2001 p 93 [19] Wang T, Li K, Liu Q, Zhang Q, Qiu S, Long J, et al Aviation fuel synthesis by catalytic conversion of biomass hydrolysate in aqueous phase Appl Energy 2014;136:775–80
[20] Fu J, Yang C, Wu J, Zhuang J, Hou Zh, Lu X Direct production of aviation fuels from microalgae lipids in water Fuel 2015;139:678–83
[21] Kallio P, Pasztor A, Akhtar MK, Jones PR Renewable jet fuel Curr Opin Biotechnol 2014;26:50–5
[22] Zhang Y, Bi P, Wang J, Jiang P, Wu X, Xue H, et al Production of jet and diesel biofuels from renewable lignocellulosic biomass Appl Energy 2015;150: 128–37
[23] Wang J, Bi P, Zhang Y, Xue H, Jiang P, Wu X, et al Preparation of jet fuel range hydrocarbons by catalytic transformation of bio-oil derived from fast pyrolysis
of straw stalk Energy 2015;86:488–99 [24] Wang T, Qiu S, Weng J, Chen L, Liu Q, Long J, et al Liquid fuel production by aqueous phase catalytic transformation of biomass for aviation Appl Energy 2015;160:329–35
[25] Bi P, Wang J, Zhang Y, Jiang P, Wu X, Liu J, et al From lignin to cycloparaffins and aromatics: directional systhesis of jet and diesel fuel range biofuels using biomass Bioresour Technol 2015;183:10–7
[26] Carlson TR, Tompsett GA, Conner WC, George Aromatic production from catalytic fast pyrolysis of biomass-derived feedstocks Top Catal 2009;52:241–52
[27] Olcay H, Subrahmanyam AV, Xing R, Lajoie J, Dumesic JA, Huber GW Production of renewable petroleum refinery diesel and jet fuel feedstocks from hemicellulose sugar streams Energy Environ Sci 2013;6:205–16 [28] Hudaya T, Rionardi A, Soerawidjaja TH Electrochemical hydrogenation of terpene hydrocarbons In: International seminar on biorenewable resources utilization for energy and chemicals Bandung, Indonesia 10–11 October 2013 [29] Fiswell NJ The influence of fuel composition on smoke emission from gas-turbine-type combustors: effect of combustor design and operating conditions Combust Sci Technol 1979;19:119–27
[30] Speight JG The chemistry and technology of petroleum 4th ed New York: CRC Press; 2006
[31] Altman R Aviation alternative fuels, characterizing the options In: Aviation and alternative fuels (ICAO) Montreal, Canada: ICAO; 2009
[32] Wey C, Powell EA, Jagoda JI The effect of temperature on the sooting behavior
of laminar diffusion flames Combust Sci Technol 1984;41:173–90 [33] Lefebvre AH, Ballal DR Gas turbine combustion 3th ed CRC Press; 2010 p 39 [34] Olson DB, Pickens JC, Gill RJ The effects of molecular structure on soot formation II Diffusion flames Combust Flame 1985;62:43–60
[35] Watson RJ, Botero ML, Ness CJ, Morgan NM, Kraft M An improved methodology for determining threshold sooting indices from smoke point lamps Fuel 2013;111:120–30
[36] Jeon BH, Fujita O, Nakamura Y, Ito H Effect of co-axial flow velocity on soot formation in a laminar jet diffusion flame under microgravity J Therm Sci Technol 2007;2(2):281–90
[37] Saffaripour M, Veshkini A, Kholghy M, Thomson MJ Experimental investigation and detailed modeling of soot aggregate formation and size distribution in laminar coflow diffusion flames of Jet A-1, a synthetic kerosene, and n-decane Combust Flame 2014;161:848–63
[38] Merchan-Merchan W, McCollam S, Pugliese JFC Soot formation in diffusion oxygen-enhanced biodiesel flames Fuel 2015;156:129–41
[39] Feng Q, Jalali A, Fincham AM, Wang JL, Tsotsis TT, Egolfopoulos FN Soot formation in flames of model biodiesel fuels Combust Flame 2012;159 (5):1876–93
[40] Snelling DR, Thomson KA, Smallwood GJ, Gulder OL Two-dimensional imaging
of soot volume fraction in laminar diffusion flames Appl Opt 1999;38:2478–85 [41] Greenberg PS, Ku JC Soot volume fraction imaging Appl Opt 1997;36:5514–22
[42] Dalzell WH, Sarofim AF Optical constants of soot and their application to heat-flux calculations J Heat Transfer 1969;91(4):91–100
[43] ASTM D1322 Standard test method for smoke point of kerosine and jet fuel American Society for Testing and Materials; 2012
[44] Nadkarni RAK Guide to ASTM test methods for the analysis of petroleum products and lubricants West Conshohocken, PA: American Society for Testing and Materials; 2000 p 152
[45] Hoekman SK, Broch A, Robbins C, Ceniceros E, Natarajan M Review of biodiesel composition, properties, and specifications Renew Sustain Energy Rev 2012;16:143–69
[46] Knothe G, Gerpen JV, Krahl J The biodiesel handbook Cham-paign, Illinois: AOCS Press; 2005
Trang 8[47] Speight JG In: Julian Hunt FRS, editor The biofuels handbook RSC energy
series, vol 5 Science Park, Milton Road, Cambridge CB4 0WF, UK: The Royal
Society of Chemistry, Thomas Graham House; 2011 p 92
[48] Clarke AE, Hunter TG, Garner FH Tendency to smoke of organic substances on
burning: part I Ind Eng Chem 1946;32:627–42
[49] Hunt RA Relation of smoke point to molecular structure Ind Eng Chem
1953;45(3):602–6
[50] Lappi H, Alen R, Anal J Production of vegetable oil-based biofuels:
thermochemical behavior of fatty acid sodium salts during pyrolysis J Anal
Appl Pyrol 2009;86:274–80
[51] Zhenyi C, Xing J, Shuyuan L, Li L Thermodynamics calculation of the pyrolysis
of vegetable oils Energy Sources 2004;26:849–56
[52] Van Treuren KW Sooting characteristics of liquid pool diffusion flames M.S.
thesis USA: Mechanical and Aerospace Engineering, Princeton University;
1978
[53] Li L, Sunderland PB Smoke points of fuel–fuel and fuel–inert mixtures Fire Saf
J 2013;61:226–31
[54] Kewley J, Jackson JS The burning of mineral oils in wick-fed lamps J Inst Petrol
Technol 1927;13:364–82
[55] Minchin ST Luminous stationary flames: the quantitative relationship
between flame dimensions at sooting point and chemical composition with
special reference to petroleum hydrocarbons J Inst Petrol Technol 1931;17:102–20
[56] Mensch A, Santoro RJ, Litzinger TA, Lee SY Sooting characteristics of surrogates for jet fuels Combust Flame 2010;157:1097–105
[57] Calcote HF, Manos DM Effect of molecular structure on incipient soot formation Combust Flame 1983;49:289–304
[58] Barrientos EJ, Lapuerta M, Boehman AL Group additivity in soot formation for the example of C-5 oxygenated hydrocarbon fuels Combust Flame 2013;160:1484–98
[59] Llamas A, Lapuerta M, Al-Lal A, Canoira L Oxygen extended sooting index of fame blends with aviation kerosene Energy Fuels 2013;27(11):6815–22 [60] Jiao Q, Anderson JE, Wallington TJ, Kurtz EM Smoke point measurements of diesel-range hydrocarbon–oxygenate blends using a novel approach for fuel blend selection Energy Fuels 2015;29:7641–9
[61] Barrientos EJ, Anderson JE, Maricq MM, Boehman AL Particulate matter indices using fuel smoke point for vehicle emissions with gasoline, ethanol blends, and butanol blends Combust Flame 2016;167:308–19
[62] Gómez A, Soriano JA, Armas O Evaluation of sooting tendency of different oxygenated and paraffinic fuels blended with diesel fuel Fuel 2016;184:536–43 [63] Affens WA, Hall JM, Holt S, Hazlett RN Effect of composition on freezing points
of model hydrocarbon fuels Fuel 1984;64:543–7