U.S. patent application number 13/480562 was filed with the patent office on 2012-09-20 for fuel composition for a diesel engine.
This patent application is currently assigned to Neste Oil Oyj. Invention is credited to Pekka AALTO, Juha JAKKULA, Ulla KIISKI, Seppo MIKKONEN, Vesa NIEMI, ]ouko NIKKONEN, Outi PIIRAINEN.
Application Number | 20120233911 13/480562 |
Document ID | / |
Family ID | 31997729 |
Filed Date | 2012-09-20 |
United States Patent
Application |
20120233911 |
Kind Code |
A1 |
JAKKULA; Juha ; et
al. |
September 20, 2012 |
FUEL COMPOSITION FOR A DIESEL ENGINE
Abstract
The invention is directed to a fuel composition for diesel
engines. The fuel composition comprises 0.1-99% by weight of a
component or a mixture of components produced from biological raw
material originating from plants and/or animals and/or fish. The
fuel composition comprises 0-20% of components containing oxygen.
Both components are mixed with diesel components based on crude oil
and/or fractions from Fischer-Tropsch process.
Inventors: |
JAKKULA; Juha; (Kerava,
FI) ; AALTO; Pekka; (Porvoo, FI) ; NIEMI;
Vesa; (Porvoo, FI) ; KIISKI; Ulla; (Hamari,
FI) ; NIKKONEN; ]ouko; (Hamari, FI) ;
MIKKONEN; Seppo; (Porvoo, FI) ; PIIRAINEN; Outi;
(Helsinki, FI) |
Assignee: |
Neste Oil Oyj
Espoo
FI
|
Family ID: |
31997729 |
Appl. No.: |
13/480562 |
Filed: |
May 25, 2012 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
12354634 |
Jan 15, 2009 |
8187344 |
|
|
13480562 |
|
|
|
|
11852096 |
Sep 7, 2007 |
|
|
|
12354634 |
|
|
|
|
10655798 |
Sep 5, 2003 |
7279018 |
|
|
11852096 |
|
|
|
|
60408302 |
Sep 6, 2002 |
|
|
|
Current U.S.
Class: |
44/308 ;
44/307 |
Current CPC
Class: |
Y02P 30/20 20151101;
C10L 1/32 20130101; C10G 3/50 20130101; C10L 1/08 20130101 |
Class at
Publication: |
44/308 ;
44/307 |
International
Class: |
C10L 1/188 20060101
C10L001/188; C10L 1/19 20060101 C10L001/19 |
Claims
1-7. (canceled)
8. A method for reducing nitrogen oxide emissions of a diesel
engine, comprising: (a) preparing a diesel fuel of biological
origin consisting of at least one component produced by a process
comprising: (1) providing a feed stream of fatty acids, fatty acid
esters, or both, derived from at least one biological raw material
originating from animals or from animals in combination with plants
and/or fish; (2) hydrodeoxygenating the feed stream to form
n-paraffins; and (3) isomerizing the n-paraffins to form
isoparaffins, in which the diesel fuel of biological origin is free
of aromatics and has a cetane number higher than 60; and (b) using
the diesel fuel of biological origin in a diesel engine, in which
the nitrogen oxide emissions of the diesel engine are less than the
nitrogen oxide emissions of the same engine using a diesel fuel
derived from crude oil.
9. The method of claim 8, further comprising combining the diesel
fuel of biological origin with a diesel fuel derived from crude oil
before using the diesel fuel of biological origin in the diesel
engine.
10. The method of claim 8, in which the biological raw material is
selected from animal-based fats, fats contained in milk, recycled
fats of the food industry, or mixtures thereof.
11. The method of claim 8, in which the fatty acid esters are
triglycerides.
12. The method of claim 8, in which the diesel fuel of biological
origin has a turbidity point lower than -30.degree. C.
13. A method for reducing nitrogen oxide emissions of a diesel
engine, comprising: (a) selecting a diesel fuel of biological
origin consisting of at least one component produced by a process
comprising: (1) providing a feed stream of fatty acids, fatty acid
esters, or both, derived from at least one biological raw material
originating from animals or from animals in combination with plants
and/or fish; (2) hydrodeoxygenating the feed stream to form
n-paraffins; and (3) isomerizing the n-paraffins to form
isoparaffins, in which the diesel fuel of biological origin is free
of aromatics and has a cetane number higher than 60; and (b) using
the diesel fuel of biological origin in the diesel engine, in which
the nitrogen oxide emissions of a diesel engine are less than the
nitrogen oxide emissions of the same engine using a diesel fuel
derived from crude oil.
14. The method of claim 13, further comprising combining the diesel
fuel of biological origin with a diesel fuel derived from crude oil
before using the diesel fuel of biological origin in the diesel
engine.
15. The method of claim 13, in which the biological raw material is
selected from animal-based fats, fats contained in milk, recycled
fats of the food industry, or mixtures thereof.
16. The method of claim 13, in which the fatty acid esters are
triglycerides.
17. The method of claim 13, in which the diesel fuel of biological
origin has a turbidity point lower than -30.degree. C.
18. A diesel fuel of biological origin consisting of at least one
component produced by a process comprising: (1) providing a feed
stream of fatty acids, fatty acid esters, or both, derived from at
least one biological raw material originating from animals or from
animals in combination with plants and/or fish; (2)
hydrodeoxygenating the feed stream to form n-paraffins; and (3)
isomerizing the n-paraffins to form isoparaffins, in which the
diesel fuel of biological origin is free of aromatics, has a cetane
number higher than 60, and reduces nitrogen oxide emissions of a
diesel engine as compared to the same engine using a diesel fuel
derived from crude oil.
19. The diesel fuel of claim 18, in which the biological raw
material is selected from fats, oils, and mixtures thereof.
20. The diesel fuel of claim 18, wherein the biological raw
material is selected from animal-based fats; fats contained in
milk; recycled fats of the food industry; wood-based fats or oils;
non-wood, plant-based fats or oils; fats contained in plants bred
by means of gene manipulation; fish oils; and mixtures thereof.
21. The diesel fuel of claim 18, in which the biological raw
material originates from a combination of animals and plants.
22. The diesel fuel of claim 18, in which the fatty acid esters are
triglycerides.
23. The diesel fuel of claim 18 having a turbidity point lower than
-30.degree. C.
24. A method of producing a diesel fuel of biological origin
consisting of at least one component produced by a process
comprising: (1) providing a feed stream of fatty acids, fatty acid
esters, or both, derived from at least one biological raw material
originating from animals or from animals in combination with plants
and/or fish; (2) hydrodeoxygenating the feed stream to form
n-paraffins; and (3) isomerizing the n-paraffins to form
isoparaffins; in which the diesel fuel of biological origin is free
of aromatics and has a cetane number higher than 60.
25. The method of claim 24, in which the diesel fuel of biological
origin reduces nitrogen oxide emissions of a diesel engine as
compared to the same engine using a diesel fuel derived from crude
oil.
26. The method of claim 24, in which the biological raw material is
selected from animal-based fats, fats contained in milk, recycled
fats of the food industry, or mixtures thereof.
27. The method of claim 24, in which the hydrodeoxygenating process
is performed in a countercurrent manner.
28. The method of claim 24, in which the isomerizing process is
performed in a countercurrent manner.
29. The method of claim 27, in which the isomerizing process is
performed in a countercurrent manner.
30. The method of claim 24, in which the fatty acid esters are
triglycerides.
31. The method of claim 24, in which the diesel fuel has a
turbidity point lower than -30.degree. C.
Description
[0001] This application is a Divisional of co-pending application
Ser. No. 11/852,096 filed on Sep. 7, 2007, and for which priority
is claimed under 35 U.S.C. .sctn.120; and this application claims
priority of application Ser. No. 10/655,798 filed on Sep. 5, 2003
for which priority is claimed under 35 U.S.C. .sctn.120; and this
application claims priority of Application No. 60/408,302 filed on
Sep. 6, 2002 under 35 U.S.C. .sctn.119; the entire content of each
of which is hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a fuel composition for
diesel engines, comprising components based on vegetable oil and/or
animal fat and/or fish oil, diesel components based on crude oil
and/or fractions from Fischer-Tropsch process, and optionally
components containing oxygen.
PRIOR ART
[0003] Currently used fuels for diesel engines mainly contain
components from crude oil. The aim of the climate agreement of
Kyoto is to eliminate detrimental influences due to human
activities on the atmosphere, and thus on the climate. The EU has
agreed on reducing emissions of carbon dioxide, methane and other
greenhouse gases by eight percent until 2010, starting from the
levels of 1990. One of the objects of the EU agricultural policy is
to find uses for agricultural overproduction, and to increase the
self-sufficiency for fuels. Accordingly, an EU directive is being
prepared, demanding that at least two percent of the petrol and
diesel fuel consumed in 2005 should be of biological origin. It is
anticipated that one of the requirements of this directive is to
increase the proportion of biocomponents to about six percent until
2010. The directive will be validated in all EU countries in the
near future.
At the moment, the most common component of biological origin in
fuels is rapeseed oil methyl ester, referred to as RME. RME is
either used as such or as a mixture with fuels. Drawbacks of RME
are its poor miscibility with diesel fuels, and, in comparison to a
conventional diesel fuel (EN 590), particularly under low
temperature conditions, its poor storage stability and poor
performance at low temperatures. Moreover, it causes engine fouling
and increases emissions of nitrogen oxides (NOx). A by-product of
the production process of RME is glycerol, which may become a
problem when high amounts of the product are produced--Esters of
other vegetable oils may be produced in similar manner, and methyl
esters of fatty acids are generally known as FAMEs (fatty acid
methyl ester). These FAMEs may be used in similar applications as
the rapeseed oil methyl ester, but they also have a negative effect
on the quality of the diesel fuel, particularly with respect to the
performance thereof at low temperatures, and in addition, the use
thereof in fuels increases the emissions of nitrogen oxides. In
some cases FAME and RME cause higher particle emissions and smoke
development of the cold driven engine.
[0004] Vegetable oils and animal fats may be processed to decompose
the ester and/or fatty acid structure and to saturate the double
bonds of the hydrocarbon chains, thus obtaining about 80 to 85% of
n-paraffin product relative to the mass of the starting material.
This product may be directly mixed with a diesel fuel, but a
problem with the fuel so produced is its poor performance at low
temperatures. In addition, n-paraffins having a carbon number of
fatty acids are waxy with a high solidification point, typically
above +10.degree. C., thus limiting the use of these compounds in
diesel fuels at least at low temperatures.
[0005] WO 2001049812 discloses a method for producing a diesel fuel
with a molar ratio of iso-paraffins to n-paraffins of at least
21:1. In the method, a feed stock containing at least 50% of
C10-paraffins is contacted with a catalyst in the isomerization
reaction zone.
[0006] WO 2001012581 discloses a method for producing methyl esters
useful as biological diesel fuel, wherein mixtures of fatty acids
and triglycerides are esterified in one phase. In this method, a
solution is formed from fatty acids, triglycerides, alcohol, acid
catalyst and co-solvents at a temperature below the boiling point
of the solution. A co-solvent is used in amounts to provide a
single phase, then the solution is maintained for a period of time
sufficient for the acid catalyzed esterification of the fatty acids
to take place. Thereafter, the acid catalyst is neutralized, a base
catalyst is added to transesterify the triglycerides, and finally,
the esters are separated from the solution. Thus a biofuel
containing esters is obtained, having a glycerol content of less
than 0.4% by weight
[0007] U.S. Pat. No. 6,174,501 presents a method for producing
oxidized diesel fuel of biological origin. This oxidized biological
diesel fuel comprises a mixture of transesterified
triglycerides.
[0008] FI 100248 describes a two-step process for producing middle
distillate from vegetable oil by hydrogenating fatty acids of the
vegetable oil, or triglycerides, to give n-paraffins, and then by
isomerizing the n-paraffins to give branched-chain paraffin-Any
gases, liquid droplets and solid particles present in the
atmosphere in amounts being hazardous to human health and/or having
a detrimental effect on animals, plants and different materials,
are considered as air pollutants. Air pollution mainly originates
from three main emission sources, i.e., the industry, energy
production, and traffic.
[0009] The harmfulness of particle emissions is caused by the
substances and compounds they carry, such as heavy metals and other
carcinogenic and mutagenic compounds. Particles present in exhaust
gases are small and thus hazardous to health.
[0010] Greenhouse gases allow for the penetration of the radiation
from the sun to reach the earth, preventing, however, the thermal
radiation from escaping from the earth back to space. They thus
contribute to the warming of the earth. One of the most significant
greenhouse gases is carbon dioxide released, for instance, during
the combustion of fossil fuels.
[0011] Nitrogen oxides are acidifying compounds. This acidification
may, for instance, lead to plant damages and species changes in
surface waters. Nitrogen oxides may also react with oxygen to give
ozone. This phenomenon contributes particularly to air quality in
cities.
[0012] As the above teachings indicate, there is a need for a high
quality fuel composition for diesel engines containing components
of biological origin and also meeting the quality requirements for
diesel fuels under low temperature operation conditions. Moreover,
the fuel should be more environmentally friendly than prior art
solutions.
GENERAL DESCRIPTION OF THE INVENTION
[0013] The object of the invention is to provide a more
environmentally friendly fuel composition for diesel engines
containing components of biological origin, and also meeting the
quality requirements for diesel fuels under low temperature
conditions.
[0014] The fuel composition for diesel engines of the invention,
containing components of biological origin, comprises at least one
component produced from a biological starting material obtained
from plants, animals or fish, diesel components based on crude oil
and/or fractions from Fischer-Tropsch process, and optionally
components containing oxygen.
[0015] The characteristic features of the fuel composition for
diesel engines containing components of biological origin are
presented in the appended claims.
DETAILED DESCRIPTION A OF THE INVENTION
[0016] It was surprisingly found that the diesel fuel composition
of the invention, containing components of biological origin, also
meets the quality requirements for diesel fuels under low
temperature conditions. The composition of the diesel fuel of the
invention comprises the following:
a) 0.1 to 99% by volume, preferably 0.1 to 80% by volume of a
component or a mixture of components produced from biological raw
material originating from plants and/or animals and/or fish; b) 0
to 20% by volume of components containing oxygen selected from the
group consisting of aliphatic alcohols such as methanol and
ethanol, ethers, fatty acid esters such as methyl and ethyl esters,
water, and mixtures containing the same; both components a) and b)
being mixed as an emulsion or dissolved in diesel components based
on crude oil and/or fractions from Fischer-Tropsch process.
[0017] Component a) produced from biological raw material
originating from plants and/or animals and/or fish, referred to as
the biological component in the present specification, is obtained
by hydrogenating and decomposing fatty acids and/or fatty acid
esters to give a hydrocarbon having a carbon number of 6-24,
typically n-paraffin as the product having a carbon number of
12-24, and optionally by isomerizing the hydrocarbon, typically
n-paraffin, thus obtained to give isoparaffin. The hydrocarbon is
preferably isomerized.
[0018] The biological raw material originating from plants and/or
animals and/or fish is selected from the group consisting of
vegetable oils, animal fats, fish oils and mixtures thereof
containing fatty acids and/or fatty acid esters. Examples of
suitable materials are wood-based and other plant-based fats and
oils such as rapeseed oil, colza oil, canola oil, tall oil,
sunflower oil, soybean oil, hempseed oil, olive oil, linseed oil,
mustard oil, palm oil, peanut oil, castor oil, coconut oil, as well
as fats contained in plants bred by means of gene manipulation,
animal-based fats such as lard, tallow, train oil, and fats
contained in milk, as well as recycled fats of the food industry
and mixtures of the above.
[0019] The basic component of a typical vegetable or animal fat is
triglyceride i.e., a triester of glycerol and three fatty acid
molecules having the structure presented in the following formula
I:
where RI, R2, and R3 are hydrocarbon chains, and R, R2, and R3 may
be saturated or unsaturated C6-C24 alkyl groups. The fatty acid
composition may vary considerably in biological raw materials of
different origin. n-paraffin, iso-paraffin or mixtures thereof
produced from the biological raw material may be used as a diesel
fuel component in accordance with the properties desired for the
diesel fuel. Fractions from Fischer-Tropsch-process typically
contain high levels of n-paraffin and, optionally, they may be
isomerized either simultaneously during the processing of the
##STR00001##
component of biological origin or separately therefrom, or they may
be used as such.
[0020] The biological component may be produced, for instance, with
a process comprising at least two steps and optionally utilizing
the counter-current operation principle. In the first
hydrodeoxygenation step of the process, optionally running
counter-current, the structure of the biological raw material is
broken, compounds containing oxygen, nitrogen, phosphor and sulphur
as well as light hydrocarbons as gas are removed, and thereafter,
olefinic bonds are hydrogenated. In the second isomerization step
of the process, optionally running counter-current, isomerization
is carried out to give branched hydrocarbon chains, thus improving
the low temperature properties of the paraffin.
[0021] Biological raw material originating from plants, animals or
fish and containing fatty acids and/or fatty acid esters, selected
from vegetable oils, animal fats, fish oils and mixtures thereof,
is used as the feed stock.
[0022] High quality hydrocarbon component of biological origin,
particularly useful as a component of a diesel fuel, as an
isoparaffinic solvent and as a lamp oil, is obtained as the product
having a high cetane number that may even be higher than 70. Also,
with a turbidity point lower than -30.degree. C. a cetane number
higher than 60 can still be achieved. The process can be adjusted
according to the desired cetane number and turbidity point.
[0023] Advantages of the diesel fuel composition of the present
invention include superior performance at low temperatures and an
excellent cetane number compared to solutions of prior art using
FAME-based components like RME. Problems associated with the
performance at low temperatures may be avoided by isomerizing waxy
n-paraffins having a carbon number comparable with that of fatty
acids to give isoparaffins. The properties of the products thus
obtained are excellent, especially with respect to diesel
applications, the n-paraffins typically have cetane numbers higher
than 70, and isoparaffins higher than 60, and thus they have an
improving effect on the cetane number of the diesel pool, which
clearly makes them more valuable as diesel components. Moreover,
the turbidity point of the isomerized product may be adjusted to
the desired level, for example below -30.degree. C., whereas the
corresponding value is about 0.degree. C. for RME and more than
+15.degree. C. for n-paraffins. Table 1 below compares the
properties of an isomerized biological component, RME, and a
commercial diesel fuel.
TABLE-US-00001 TABLE 1 Density Cetane Turbidity Product
(kg/m.sup.3) number point (.degree. C.) Isomerized biological
component C 800 >60 -30 RME -880 -50 -0 Diesel fuel EN 590
820-845 >51 0 to -15
[0024] Fouling of engines is considerably diminished and the noise
level is clearly lower when using the diesel fuel composition of
the invention in comparison with similar prior art fuels of
biological origin containing FAME components, and further, the
density of the composition is lower. The composition does not
require any modifications of the automobile technology or
logistics. Higher energy content per unit volume may be mentioned
as a further advantage compared to RME.
[0025] The properties of the diesel fuel composition of biological
origin according to the invention correspond to those of a high
quality diesel fuel based on crude oil, it is free of aromates and,
in contrast to FAME, it leaves no impurity residues.
[0026] Nitrogen oxide emissions due to the fuel composition of the
invention are lower that those from a similar FAME-based product,
and further, the particle emissions are clearly lower, and the
carbon portion of the particles is smaller. These significant
improvements in the emissions of the fuel composition of biological
origin are environmentally very important.
[0027] The invention will now be illustrated by means of the
following examples without intending to limit the scope
thereof.
EXAMPLES
Example 1
[0028] The following Table 2 compares the emission characteristics
of a conventional diesel fuel used in Europe in summer, EN 590
(DI), to those of a composition containing 60% by volume of
hydrogenated and isomerized tall oil (TOFA), and 40% by volume of
the European summer diesel fuel EN 590.
TABLE-US-00002 TABLE 2 Characteristic Unit 60% b.v. TOFA + 40% b.v.
DI DI Turbidity point .degree. C. -15 -8 Cetane number 61.2 55.9
Aromates % b.w. 8.7 19.2 Total aromates (IP391) % b.v. 9.1 20.0
Polyaromates (1P391) % b.v. 0.8 1.6 n-paraffins % b.w. 14_7 24.5
i-paraffins % b.w. 34.2 26.1 Naphtenes % b.w. 42.4 30.2 b.w. = by
weight b.v. = by volume
Example 2
[0029] Table 3 below compares the emission characteristics of a
high quality reformed crude oil based diesel fuel available on the
Finnish market (DITC, produced by Fortum Oyj), to those of
compositions containing 30% by volume of hydrogenated and
isomerized tall oil (TOFA), and 70% by volume of DITC, or
containing 30% by volume of tall oil methyl ester (MME), and 70% by
volume of DITC.
TABLE-US-00003 TABLE 3 30% b.v. TOFA 30% b.v. MME Characteristic
Unit DITC 70% b.v. DITC 70% b.v. DITC Cetane number 51 57 48 NO,
emissions % -1 to -4 +3 (compared to DITC) Particles % -3 +22
carbon % -10 to -30 0 to -10 PAH % .+-.0 .+-.0 Combustion noise
decreases .+-.0 b.v. = by volume
* * * * *