U.S. patent application number 16/093715 was filed with the patent office on 2019-05-02 for dimethyl ether blended fuel alternative for diesel engines.
The applicant listed for this patent is The Regents of The University of Michigan. Invention is credited to Andre BOEHMAN, Taemin KIM.
Application Number | 20190127650 16/093715 |
Document ID | / |
Family ID | 60117081 |
Filed Date | 2019-05-02 |
United States Patent
Application |
20190127650 |
Kind Code |
A1 |
BOEHMAN; Andre ; et
al. |
May 2, 2019 |
DIMETHYL ETHER BLENDED FUEL ALTERNATIVE FOR DIESEL ENGINES
Abstract
A dimethyl ether blended fuel having a fuel composition
including dimethyl ether (DME), glycerol, and a co-solvent, wherein
the fuel composition achieving a kinematic viscosity of at least
0.2 centistokes (cSt).
Inventors: |
BOEHMAN; Andre; (Ann Arbor,
MI) ; KIM; Taemin; (Ann Arbor, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
The Regents of The University of Michigan |
Ann Arbor |
MI |
US |
|
|
Family ID: |
60117081 |
Appl. No.: |
16/093715 |
Filed: |
April 18, 2017 |
PCT Filed: |
April 18, 2017 |
PCT NO: |
PCT/US2017/028024 |
371 Date: |
October 15, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62323953 |
Apr 18, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10L 1/1826 20130101;
C10L 1/026 20130101; C10L 1/1852 20130101; C10L 1/125 20130101;
C10L 2270/04 20130101; C10L 2270/026 20130101 |
International
Class: |
C10L 1/185 20060101
C10L001/185; C10L 1/02 20060101 C10L001/02; C10L 1/182 20060101
C10L001/182 |
Claims
1. A dimethyl ether blended fuel comprising: a fuel composition
having dimethyl ether (DME), glycerol, and a co-solvent, wherein
the fuel composition having a kinematic viscosity of at least 0.2
centistokes (cSt).
2. The dimethyl ether blended fuel according to claim 1 wherein the
fuel composition having a kinematic viscosity of at least 1.3
centistokes (cSt)
3. The dimethyl ether blended fuel according to claim 1 wherein the
fuel composition having a kinematic viscosity of at least 1.9
centistokes (cSt)
4. The dimethyl ether blended fuel according to claim 1 wherein the
co-solvent comprises Di-propylene glycol (DPG).
5. The dimethyl ether blended fuel according to claim 4 wherein the
fuel composition having a binary mixture of DPG and glycerol of
about 54 wt. %.
6. The dimethyl ether blended fuel according to claim 5 wherein the
binary mixture of DPG and glycerol has about 34.02 wt. % DPG and
19.98 wt. % of glycerol.
7. The dimethyl ether blended fuel according to claim 4 wherein the
fuel composition having a binary mixture of DPG and glycerol of
about 60 wt. %.
8. The dimethyl ether blended fuel according to claim 7 wherein the
binary mixture of DPG and glycerol has about 35.40 wt. % DPG and
24.6 wt. % of glycerol.
9. The dimethyl ether blended fuel according to claim 1 wherein the
co-solvent comprises propylene glycol (PG).
10. The dimethyl ether blended fuel according to claim 9 wherein
the fuel composition having a binary mixture of PG and glycerol of
about 52 wt. %.
11. The dimethyl ether blended fuel according to claim 10 wherein
the binary mixture of DPG and glycerol has about 34.05 wt. % PG and
17.94 wt. % of glycerol.
12. The dimethyl ether blended fuel according to claim 9 wherein
the fuel composition having a binary mixture of PG and glycerol of
about 58 wt. %.
13. The dimethyl ether blended fuel according to claim 12 wherein
the binary mixture of DPG and glycerol has about 36.11 wt. % PG and
21.88 wt. % of glycerol.
14. The dimethyl ether blended fuel according to claim 1 wherein
the DME comprises water.
15. The dimethyl ether blended fuel according to claim 14 wherein
the DME comprise 5 wt. % water.
16. The dimethyl ether blended fuel according to claim 1, wherein
the fuel composition comprises 6.4 to 35 wt. % DPG and 39.2 to 91.9
wt. % DME, and the kinematic viscosity is between 0.2 to 1.84.
17. The dimethyl ether blended fuel according to claim 1, wherein
the fuel composition comprises 7.6 to 37.9 wt. % PG and 39.2 to
91.9 wt. % DME, and the kinematic viscosity is between 0.2 to 2.43
cSt.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This PCT application claims the benefit of Provisional
Application No. 62/323,953, filed Apr. 18, 2016. The entire
disclosure of the above application is incorporated herein by
reference.
FIELD
[0002] The present disclosure relates to improvement of the
viscosity of dimethyl ether through blending with glycerol and
oxygenated co-solvents.
BACKGROUND AND SUMMARY
[0003] This section provides background information related to the
present disclosure which is not necessarily prior art. This section
also provides a general summary of the disclosure, and is not a
comprehensive disclosure of its full scope or all of its
features.
[0004] Diesel fuel is a liquid fuel used in diesel engines, noted
for its ability to combust through compression alone without a
spark, and widely used for vehicles and stationary installations
worldwide. It is most commonly made from petroleum and is
energetically more favorable than gasoline. However, its combustion
in compression ignition engines tends to produce much more soot
than does the combustion of gasoline in spark ignition engine. Due
to the high amount of soot emission, diesel fuel is currently
burned in compression ignition engines with the use of diesel
particulate filter (DPF) and electronic unit to control the
operation of DPF, which adds to both the complexity and cost of the
after-treatment system.
[0005] Dimethyl ether (DME) is a chemical that could potentially
serve as an alternate to petroleum diesel, with advantages of a
high cetane number (indicating faster combustion speed) as well as
very low emissions meeting environmental regulations. However, DME
by itself does not have the viscosity of standard diesel, and thus
any engine fuel system using DME must be specially designed or
highly customized.
[0006] Dimethyl ether (DME) is a potential petroleum diesel fuel
replacement that can eliminate soot and other particulate emissions
and has a high cetane number indicating improved ignitibility.
However, DME has extremely low viscosity compared to standard
diesel, and its use in vehicles requires special modifications to
fuel injection and management systems. A new DME fuel blend now
seeks to overcome that obstacle, bringing viscosity to ASTM
standards for No. 1 and No. 2 diesel (depending on the mixture
composition) while preserving the clean combustion benefits for use
in existing diesel engines with minimal modification.
[0007] The present invention is two types of homogeneous mixtures
of DME and glycerol with addition of two different co-solvents to
make DME and glycerol miscible and viscous enough to meet ASTM (an
international standards organization) requirements for No. 1 or No.
2 diesel oil (ASTM D975), the standard diesel used for
transportation purposes. Di-propylene glycol (DPG) and propylene
glycol (PG) are used as co-solvents and this resulted in two
different homogeneous ternary solutions: DME, DPG and glycerol and
DME, PG and glycerol. This would allow current diesel engines to
use the blended DME fuel with little to no modifications. This
could make DME a more attractive alternative to petroleum diesel,
especially as the European Union looks to find a standard
alternative biofuel by 2030.
[0008] Further areas of applicability will become apparent from the
description provided herein. The description and specific examples
in this summary are intended for purposes of illustration only and
are not intended to limit the scope of the present disclosure.
DETAILED DESCRIPTION
[0009] Example embodiments will now be described more fully with
reference to the accompanying drawings. Example embodiments are
provided so that this disclosure will be thorough, and will fully
convey the scope to those who are skilled in the art. Numerous
specific details are set forth such as examples of specific
components, devices, and methods, to provide a thorough
understanding of embodiments of the present disclosure. It will be
apparent to those skilled in the art that specific details need not
be employed, that example embodiments may be embodied in many
different forms and that neither should be construed to limit the
scope of the disclosure. In some example embodiments, well-known
processes, well-known device structures, and well-known
technologies are not described in detail.
[0010] The terminology used herein is for the purpose of describing
particular example embodiments only and is not intended to be
limiting. As used herein, the singular forms "a," "an," and "the"
may be intended to include the plural forms as well, unless the
context clearly indicates otherwise. The terms "comprises,"
"comprising," "including," and "having," are inclusive and
therefore specify the presence of stated features, integers, steps,
operations, elements, and/or components, but do not preclude the
presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. The
method steps, processes, and operations described herein are not to
be construed as necessarily requiring their performance in the
particular order discussed or illustrated, unless specifically
identified as an order of performance. It is also to be understood
that additional or alternative steps may be employed.
[0011] The principles of the present teachings provide a dimethyl
ether blended fuel employing di-propylene glycol (DPG) or propylene
glycol (PG) to improve the miscibility of DME (very low viscosity)
with glycerol (highly viscous). This results in two types of
homogeneous blends that both meet ASTM D975 kinematic viscosity
specifications while remaining largely DME (near 50%). Table 1
shows the kinematic viscosity standard for No. 1 diesel and No. 2
diesel in ASTM D975.
TABLE-US-00001 TABLE 1 No. 1 Diesel No. 2 Diesel (For all sulfur
grades) (For all sulfur grades) Min. Kinematic Viscosity 1.3 1.9
(@40.degree. C.), [cSt] Max. Kinematic Viscosity 2.4 4.1
(@40.degree. C.), [cSt]
[0012] For DME/DPG/glycerol mixture, experimental measurement shows
that
54 wt . % ( mass of DPG + mass of glycerol mass of DPG + mass of
glycerol + mass of DME .times. 100 ) ##EQU00001##
addition of binary mixture of DPG and glycerol (34.02 wt. %
DPG+19.98 wt. % glycerol) into DME meets the minimum kinematic
viscosity level for No. 1 diesel oil (1.3 cSt) while 60 wt. %
addition of binary mixture of DPG and glycerol (35.40 wt. %
DPG+24.6 wt. % glycerol) meets the minimum kinematic viscosity
level for No. 2 diesel oil (1.9 cSt). For DME/PG/glycerol mixture,
experimental measurement shows that 52 wt. % addition of the binary
mixture of PG and glycerol (34.05 wt. % PG +17.94 wt. % glycerol)
meets the minimum kinematic viscosity level for No. 1 diesel oil
while 58 wt. % addition of the binary mixture of PG and glycerol
(36.11 wt. % PG+21.88 wt. % glycerol) meets the minimum kinematic
viscosity level for No. 2 diesel oil. The use of fuel additives
such as Lubrizol 539 can overcome other issues such as lubricity.
This DME blend fuel will bring improved engine durability over
engines operating on neat DME and improved performance with cleaner
combustion over conventional diesel fuels.
[0013] It should be understood that the present teachings are not
limited to the aforementioned mixtures with specific mixture
composition. In some embodiments, the present teachings may provide
a range of acceptable performance capable of meeting ASTM D975
standards. These teachings provide two different ternary blends
(1.DME/Glycerol/PG and 2.DME/Glycerol/DPG) at various possible
mixture composition preventing the phase separation. Table 2 shows
the minimum co-solvent (DPG or PG) weight % in two different
ternary blends to ensure the homogeneous phase of the ternary
solution, and this defines the range of our invented ternary
blends.
TABLE-US-00002 TABLE 2 Weight % Minimum co-solvent Resulting of DME
in wt. % in ternary viscosity Type of Co- the ternary blend to
ensure of the ternary solvent blend homogeneous phase solution
[cSt] Di-propylene 91.9% 6.4% 0.215 Glycol (DPG) 82.2% 14.1% 0.279
69.6% 22.7% 0.360 60.1% 28.5% 0.613 57.6% 29.1% 0.665 50.0% 33.1%
1.050 40.9% 35.0% 1.840 Propylene 90.0% 7.6% 0.222 glycerol (PG)
70.0% 21.8% 0.434 58.0% 28.7% 0.745 50.0% 32.8% 1.103 39.2% 37.9%
2.427
[0014] The present invention accommodates both aerosol grade and
fuel grade DME. Fuel grade DME will contain H2O. The present
invention yields stable, homogeneous ternary solutions in the
presence of as much as 5 wt. % H2O in the DME used to make the DME
blend fuel.
[0015] The present invention increases the viscosity of dimethyl
ether, DME, (a promising, near commercial, ultra clean, replacement
diesel fuel) to enable use of DME in conventional diesel fuel
injection systems with a modest amount of conversion of the fuel
system.
[0016] Today, dedicated diesel fuel injection systems, designed
specifically for DME, are needed to employ DME in diesel engines.
Volvo Trucks, Hino Motors, Nissan Truck, Isuzu and others have been
pursuing the development of neat DME engines for more than a
decade. In all of these engine and vehicle systems, the fuel
injection hardware must be designed from the ground up or be
heavily modified to accommodate DME. The reason for this is the
lack of lubricity and the very low viscosity (0.2 cSt at 40.degree.
C., versus 2.5 cSt typically for diesel fuels). Lubricity can be
increased using commonly available fuel additives (e.g., Lubrizol
539), but viscosity has only been able to be increased through
aggressive blending with other fuels and chemicals.
[0017] Blends as high as 75% by mass in another lubricious compound
or mixture (e.g., diesel fuel) are needed to meet the minimum
kinematic viscosity required in the ASTM D975 specification for No.
2 diesel fuels. Glycerol has a very high viscosity but has limited
miscibility in DME. A mixture of glycerol (.about.180 cSt at
40.degree. C.) and DME can achieve a commensurate viscosity
compared to No. 1 or No. 2 diesel oil by using glycol co-solvents.
Two types of the glycol co-solvents are found: di-propylene glycol
(DPG) and propylene glycol (PG). For DME/DPG/glycerol mixture,
experimental measurement shows that 54 wt. mass of DPG+mass of
glycerol/mass of DPG+mass of glycerol+mass of DME.times.100)
addition of binary mixture of DPG and glycerol (34.02 wt. %
DPG+19.98 wt. % glycerol) into DME meets the minimum kinematic
viscosity level for No. 1 diesel oil (1.3 cSt) while 60 wt. %
addition of binary mixture of DPG and glycerol (35.40 wt. %
DPG+24.6 wt. % glycerol) meets the minimum kinematic viscosity
level for No. 2 diesel oil (1.9 cSt). For DME/PG/glycerol mixture,
experimental measurement shows that 52 wt. % addition of the binary
mixture of PG and glycerol (34.05 wt. % PG+17.94 wt. % glycerol)
meets the minimum kinematic viscosity level for No. 1 diesel oil
while 58 wt. % addition of the binary mixture of PG and glycerol
(36.11 wt. % PG+21.88 wt. % glycerol) meets the minimum kinematic
viscosity level for No. 2 diesel oil. Further testing to discover a
more effective co-solvent might demonstrate higher viscosity that
exceeds the minimum ASTM kinematic viscosity of No. 2 diesel oil
with lower concentration of binary mixture of co-solvent and
glycerol.
[0018] The present invention employs alcohol or ether co-solvent
that allows glycerol to be dissolved into DME, permitting the high
viscosity of glycerol to benefit mixtures with DME and achieve the
minimum ASTM D975 kinematic viscosity specification.
[0019] Currently, diesel engines must be converted to DME operation
by using dedicated fuel injection systems designed for use with
DME. The present invention could allow current diesel fuel
injection systems to operate on DME, with only the elastomeric
components being changed over to DME compatible materials.
[0020] The foregoing description of the embodiments has been
provided for purposes of illustration and description. It is not
intended to be exhaustive or to limit the disclosure. Individual
elements or features of a particular embodiment are generally not
limited to that particular embodiment, but, where applicable, are
interchangeable and can be used in a selected embodiment, even if
not specifically shown or described. The same may also be varied in
many ways. Such variations are not to be regarded as a departure
from the disclosure, and all such modifications are intended to be
included within the scope of the disclosure.
* * * * *