EPA/AA/CTAB/88-11
Technical Reoort
Resistively Heated Metal Monolith As A
Cold Start Assist For a Methanol Engine
Interim Reoort
by
Gregory K. Piotrowski
December 1988
NOTICE
Technical Reports do not necessarily represent final EPA
decisions or positions. They are intended to present technical
analysis of issues using data which are currently available.
The purpose in the release of such reports is to facilitate the
exchange of technical information and to inform the public of
technical developments which may form the basis for a final EPA
decision, position or regulatory action.
U. S. Environmental Protection Agency
Office of Air and Radiation
Office of Mobile Sources
Emission Control Technology Division
Control Technology and Applications Branch
2565 Plymouth Road
Ann Arbor, Michigan 48105
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
ANN ARBOR. MICHIGAN 48105
OFFICE OF
AIR AND RADIATION
"~ i 9 1989
MEMORANDUM
SUBJECT: Exemption From Peer and Administrative Review
FROM:
TO:
Karl H. Hellnan, Chief VW
Control Technology and Applications Branch
Charles L. Gray, Jr., Director
Emission Control Technology Division
The attached report entitled "Resistively Heated Metal
Monolith As A Cold Start Assist For a Methanol Engine - Interim
Report," (EPA/AA/CTAB/88-11) describes the evaluation of this
technology with regard to its ability to provide a cold start
assist for a light-duty methanol engine. The primary focus of
this work was the determination of the ability of this
technology to act as a methanol dissociator capable of
supplying gaseous H2/CO fuels to an engine during cold start.
Since this report is concerned only with the presentation
of data and its analysis and does not involve matters of policy
or regulations, your concurrence is requested to waive
administrative review according to the oolicy outlined in your
directive of April 22, 1982.
Concurrence
Date:
Charles L. Gtfay,/Ji/., Dir.,
ECTD
Nonconcurrence:
Date:
Charles L. Gray, Jr., Dir., ECTD
cc: E. Burger, ECTD
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Table of Contents
Page
Number
I. Summary 1
II. Introduction 1
III. Discussion of Technology 2
IV. Program Design 2
V. Discussion of Test Results 5
A. Evaluation of Dual-Stage Unit 5
B. Evaluation of Single-stage Unit 7
C. Evaluation of Single/Duai-Stage Configuration . . 10
VI. Conclusions 13
VII. Future Effort 13
VIII.Acknowledgments 13
IX. References 14
APPENDIX A - Resistively Heated Metal Monolith Dissociator A-l
Specifications and Power Requirements
APPENDIX B - Test Engine Specifications B-l
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I. Summary
A methanol dissociation system was constructed to provide
a cold start assist for a methanol-fueled light-duty engine.
The system consisted of a fuel delivery unit, fuel injector,
and a palladium-catalyzed dissociation element. The
dissociation element substrate was resistiveiy heated and
constructed primarily from metal foil.
The objective of this experimentation was to start and
idle a 4-cylinder engine on the product gas from this methanol
dissociator.
Three different configurations of the resistiveiy heated
metal monolith were evaluated. The first consisted of a
catalyzed, heated bed followed by a catalyzed unheated bed.
The product stream from this dual-bed configuration was liquid,
rather than gaseous, under the conditions given in Section V,
Discussion, of this report. We tested a resistiveiy heated,
but uncatalyzed single-bed configuration; though the product
was vaporized rather than dissociated methanol, the test engine
started and idled without hesitation with no other fuel source
than the single injector-fed fuel vaporizer. Finally, a
two-stage system utilizing the single-bed unit as a vaporizer
and the dual-bed unit as a methanol dissociator was constructed
and evaluated. Product gas from this configuration was used to
start and idle the test engine in the same manner as the
single-bed unit. The product gas temperature out of the
dissociator was very low, approximately 130°F. This suggests
that the engine started on vaporized methanol, rather than H2
and CO gases.
II. Introduction
Light-duty M100 neat methanol-fueled engines are difficult
to start and run in cold weather because of the high boiling
point of methanol, methanol's high heat of vaporization (5.5
percent of the heat of combustion compared to less than 1
percent for gasoline), and the increased fuel flow needed for
methanol (about double that of gasoline). Gasoline-fueled
engines start with less difficulty under the same conditions
partly because of the easily ignitable light ends of this fuel
such as butanes, which are vaporized at relatively low
temperatures.
Some state-of-the-art methanol engines require the
addition of gasoline to the fuel to improve their
startability.[1] Other methanol engines utilize separate cold
start systems relying on gasoline or propane for cold start
assist.[2,3] Finally, some researchers have suggested that
stratified-charge combustion will produce reliable cold starts
of a neat methanol-fueled engine at relatively low ambient
conditions.[4]
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Methanol may be cataiytically decomposed to hydrogen and
carbon monoxide gases. Hydrogens' higher flame speed and lower
boiling point may make it an ideal cold start fuel.
The coal of <:he project was to construct and test a
methanol dissociation system that could provide H2 and CO
gaseous fuels in quantities that could be used as a cold start
assist for a methanol-fueled engine. This dissociator would
utilize resistively heated metal foil technology to provide the
energy necessary co bring the catalyst to operating
temperatures quickly.
Methanol dissociation systems using resistively heated
ceramic technology have been evaluated by EPA to determine
"their cold start assist potential.[5,6] Reference 6 refers to
a dissociation unit which was able to cold start and idle a
4-cylinder, 1.8-liter light-duty engine which had been soaked
to 43°F. We hoped to improve H2/CO yield, dissociator
durability and heat transfer to the methanol fuel beyond what
was experienced in that effort through the use of the
resistively heated metal foil.
III. Discussion of Technology
The subject technology is a. metal foil which may be
washcoated. catalyzed and resistively heated. The rolled metal
foil is encased in a metal housing; the housing is electrically
insulated from the electrified foil. Two metal contacts
protrude from the sides of the housing. Electrical contact to
a direct current power source, a 12-volt automobile battery, is
made to these contacts.
Two resistively heated monoliths were tested in this
effort. The first was a dual-bed configuration consisting of
an unheated metal monolith catalyst and a smaller resistively
heated metal monolith catalyst. The second unit was an
uncatalyzed, resistively heated monolith similar in size to the
smaller heated bed in the dual-bed configuration. The
exteriors of both housings were insulated with ceramic fiber
insulation to improve heat retention. Details are provided in
Appendix A.
The resistively heated monoliths were provided by Camet, a
manufacturer and sales agent for W. R. Grace Company. Details
relating to catalyzing the foil, packaging, and resistive
heating of the catalysts are considered proprietary to Camet
and Grace.
IV. Program Design
Three different configurations, a single-bed, a dual-bed,
and a combination of these two systems were evaluated for their
ability to provide a cold start assist. The dual-bed catalyzed
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system had the potential to act as a methanoi dissociator,
using resistive heating to first vaporize the feed methanoi and
then to supply the necessary energy for the endothermic
dissociation reaction. The single-bed, uncatalyzed monolith
was evaluated to determine the ability of the heated substrate
to transfer energy to the feed methanoi in the absence of the
larger catalyzed-but-unheated monolith located downstream. The
combination system used the single-bed unit as a vaporizer and
the dual-bed as the dissociation element.
Figure 1 contains a diagram of the system we constructed
to support the various configurations mentioned above.
Methanoi is pumped to the catalyst or vaporizer from a 2-gallon
plastic fuel tank by an electric roller-type fuel pump. The
fuel passes through stainless steel tubing fitted with a
flowmeter. The flowmeter is connected to an electrically
actuated clock. Given the proper electrical signal, the clock
and flowmeter operate simultaneously to determine fuel flow
over the desired time period.
A fuel injector was installed in the catalyst housing
approximately 3 inches from the face of. the smaller,
resistively heated metal monolith. When testing the dual-bed
unit alone, the methanoi spray impacted on the resistively
heated catalyst first before passing through to the larger,
catalyzed but unheated monolith. To prevent metering fuel
which did not pass through the injector, a recycle was provided
around the injector and the pump.
Fuel flow to the dissociator was controlled by changing
the pulse width of the non-continuous flow injector. Line
alternating current (AC) operated a Wavetek Model 193
wave/frequency generator. The equipment was used to generate
pulsed square wave signals of various widths that controlled
the quantity of fuel injected. An AC to direct current (dc)
device was then used to change the pulse to a dc signal before
it passed to the fuel injector.
Thermocouples were installed to measure liquid fuel
temperature as well as gas temperatures midbed in the monolith
and immediately after the dissociator. N2 gas was used to
replace the air in the dissociator just prior to heating. N2
was added for two reasons: 1) to encourage the dissociation of
methanoi, and 2) to provide a safety factor upon the initial
heating.
The test procedure consisted of supplying the fuel to the
resistively heated elements at various flowrates and
determining whether a vaporized fuel was produced. Provision
was made for sampling the dissociator gas product stream and
analyzing it with a gas chromatograph to determine its H2
content, if a gaseous product was generated from a catalyzed
unit.
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FIGURE 1
METHANOL DISSOCIATION SYSTEM
WAVETEK AC TO DC DISSOCIATOR
INJECTOR
AC , AC DC FUEL
•»• i » -
FUEL
FLOW METER
FUEL
FUEL PUMP
TO ENGINE
RECYCLE
FUEL
FUEL TANK
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The production and analysis of the hot product gas would
be followed by its introduction into a light-duty vehicle
engine for cold start testing.
V. Discussion of Test Results
A. Evaluation of Dual-Stage Unit
Methanol may be dissociated to hydrogen and carbon
monoxide via the reaction:
CH3OH(1) 2H2(g) + C0(g)
This reaction is endothermic; assume that the reaction
occurs at atmospheric pressure and 500°F.[7] This situation
requires the input of energy to:
1. Preheat the methanol at 148°F;
2. Vaporize the methanol at 148°F, l atmosphere
pressure;
3. Superheat the vapor to 500°F; and
4. Decompose the vapor to H2 and CO gases.
The dissociated product flowrate to start an engine
similar in displacement to our test engine has been calculated
[8,9] as 0.3 to 0.6 grams per second. Karpuk [10] in a private
communication to EPA, calculated a power requirement of 2,256
watts necessary to dissociate 2,000 g/hr of methanol at 25°C.
Our calculations of this requirement shows it to be 2,230
watts, essentially the same. We hoped that the resistively
heated monolith would generate power at a rate in excess of
these requirements and transfer energy to the fuel efficiently
to ensure at least partial dissociation in the brief timeframe
of interest.
The dual-stage unit was tested with the fuel injector
mounted in front of the resistively heated element. The spray
would then impact the heated element before passing through to
the catalyzed, unheated catalyst. Some results and conditions
of testing in this configuration are given in Table 1.
N2 gas at 2 psig was admitted into the catalyst vessel
for 1-minute prior to operation to assist the dissociation
reaction. The gas flow was shut off prior to catalyst heating
however, and remained off during the test.
The heating scheme involved preheating the catalyst for 10
seconds prior to fuel on and heating for 30 seconds following
fuel on. We measured current in the electrical leads to the
catalyst at approximately 300 amps at the beginning of heating;
current dropped in straight line fashion over the 30-second
heating period to approximately 220 amps at the conclusion of
heating. We charged the battery power source to 12 volts prior
to. each test.
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Table 1
Dual-Bed Configuration Evaluation
Variable
Specification or Result
N2 flowrate
2 psig over catalyst prior to
test, off during test
Battery voltage
11.5-12.5 volts
Voltage across monolith
during heating
9-volts
Current to monolith
290 amps at start of heating,
210-230 amps at finish
Heating scheme
Heat on for 10 seconds prior
to fuel on; heat on for 30
seconds after fuel on
Fuel to injector
Flow rates 35-140 cc over a
period of 30-33 seconds
Gas Temperatures;
Fuel into dissociator (liquid) 70-72°F
Mid-bed gas temperatures
Approximately 300°F at fuel
on; approximately 190°F at 10
seconds after fuel on;
approximately 150°F at end of
heating
Gas out of dissociator
75°F at end of test
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Fuel flow to the injector was varied from a high rate of
140 cc for a 30-second period (approximately 3.7 grams per
second) to 35cc over 30 seconds (approximately 0.9 grams per
second). Even the lowest flowrate tried here should have
provided a sufficient flow of fuel to start and idle the test
engine. Liquid temperature of the fuel was 70-72°F during this
testing.
Midbed gas temperatures varied considerably over the
duration of the test. Typically, this temperature would rise
to approximately 300°F after 10 seconds of heating with no fuel
injected. At 10 seconds after beginning the injection of fuel
(20 seconds into the test) temperatures had fallen linearly to
approximately 190°F. At the end of heating, or 40 seconds into
the test, midbed gas temperatures had fallen to 150°F. These
temperatures were consistently noted regardless of fuel
flowrate into the dissociator.
Gas temperatures out of the dissociator remained almost
constant, at 70-72°F, during this testing. This temperature
did not change when fuel flowrate into the dissociator was
varied. The dissociator product line was made of clear plastic
tubing; the product after 40 seconds of heating remained
liquid. Not enough gas was generated to enable bag sampling to
determine if any methanol dissociation to H2/CO had occurred.
It is difficult to determine why the desired reactions did
not occur and why the dissociator product stream appeared to be
liquid. Much more about the heat transfer characteristics of
the material contained in the housing would have to be known
from the manufacturer. Methanol vaporized in the resistively
heated section of the housing may be condensing in the
non-heated monolith.
It was clear that the particular configuration was
incapable in its present form to efficiently transfer the
necessary energy in a 40-second timeframe to dissociate
methanol at the required flowrate.
B. Evaluation of Single-stage Unit
The dual-stage dissociator did not produce a gaseous
product stream under the conditions given in Table 1. We next
evaluated a single-stage configuration to determine if a single
heated monolith would transfer heat to the fuel more
efficiently.
Some results and conditions of testing in. this
configuration are given in Table 2.
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Table 2
Single-Bed Configuration Evaluation
Variable
Specification or Result
flowrate
Battery voltage
Voltage across monolith
during heating
No N2 gas used
12 volts
9 volts
Current to monolith
Heating scheme
315 amps at start of heating,
210-230 amps at finish
Heat on for 10 seconds prior to
fuel on; heat on for 30 seconds
after fuel on
Fuel to injector
23-27 cc over a period of 30-32
seconds
Gas Temperatures:
Fuel into dissociator
70-72°F
Midbed gas temperature
Gas out of dissociator
Approximately 390°F at fuel on;
approximately 250°F at 10
seconds after fuel on;
approximately 145°F at end of
heating
138-145°F at end of test
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N2 gas was not used during testing in order to better
simulate actual cold start conditions. The battery used to
electrify the substrate was fully charged to 12 volts; during
testing, voltage drop across the substrate was measured at 9
volts. At the start of heating a current of 315 amps was
measured in the heating circuit; 40 seconds into the test, at
finish, the current had dropped linearly to 210-230 amps. The
same heating scheme that was used in the dual-bed evaluation
was also used here (heat 10 seconds, fuel on, heat 30
seconds). Fuel flow was measured at 23-27 cc over a period of
30 seconds, or 0.66 grams per second.
Midbed gas temperature rose to 390°F after 10 seconds of
heating. This was a considerable improvement from the 300°F
temperature noted during the dual-bed evaluation. Near the end
of each test, midbed gas temperatures dropped to 145°F. This
temperature is consistent with a flow of vaporized but not
superheated methanol vapor.
Gas temperature out of the substrate was approximately
145°F after 30 seconds of heating. This temperature is
consistent with a flow of vaporized methanol. This was again
an improvement over the 72°F~ temperature experienced with the
dual-stage unit.
We then piped the product gas from the resistively heated
monolith to a 4-cylinder light-duty engine and attempted a cold
start at 70°F. A complete description of the test engine is
given in Appendix B.
Approximately 4 feet of plastic tubing connected the
vaporizer to the EGR port. A valve to allow emissions sampling
and a flame arrestor were also located in this line. These
restrictions, however, did not combine to reduce fuel flow to
the point that engine performance at idle was noticeably
affected. Although the fuel entry passageway to the combustion
chambers was not standard (via EGR chamber to cylinders), it
proved sufficient to allow a start and idle at the conditions
in Table 2.
The engine started and idled without hesitation. Crank
time to start was 1-1/2 seconds. This experiment was
successfully repeated several times. Cranking was attempted
after 30 seconds of heating time had elapsed (the final 20
seconds of that period involved sending fuel to the heated
monolith). The four engine fuel injectors were electronically
disabled during this testing; fuel entered the engine only from
the single-injector/heater system.
We tried repeating this cold start experiment with this
same hardware but without heating the monolith. Gas
temperature out of the catalyst housing did not exceed 72°F
under the conditions in Table 2, and the engine did not start.
Disassembling the catalyst housing after this test, we
discovered it filled with liquid methanol.
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The resistive heating had the effect of vaporizing the
incoming methanol stream. The vaporized methanol, under the
conditions in Table 2, was sufficient to start and idle the
test engine in spite of the less than optimum fuel intake
system.
C. Evaluation of Single/Dual-Stage Configuration
The dual-bed configuration was not successful under the
conditions in Table 1, probably because the methanol vaporized
in the first, heated stage, had condensed on the metal foil in
the second, unheated stage. The time period of interest here
was 40 seconds; during that time current dropped significantly,
from 290 to 220 amps, due to discharge of the battery. It may
have been difficult to transfer sufficient energy effectively
from the heated to the unheated monolith in the timeframe of
interest to permit the desired reaction to occur. The
single-bed configuration heated and vaporized the methanol feed
stream. The energy transferred here in the time of interest
was sufficient to srart and idle the test engine on methanol
fuel alone. Midbed gas temperature recorded with this
configuration 10 seconds after the introduction of methanol,
250°F, was still too low to permit methanol dissociation with
the noble metal catalyst we used in the dual-bed configuration.
We next combined the single and dual-bed monoliths in an
attempt to increase the product gas temperature. The
single-bed monolith was placed first in this new configuration;
the injector sprayed on this heated monolith. The single-bed,
non-catalyzed unit would therefore act as a vaporizer ahead of
the dual-stage unit. The catalyzed dual-stage unit would then
be the dissociator, receiving a vaporized product gas from the
single-bed unit.
Two uncertainties still remained with this approach,
however. Though we measured midbed gas temperature, we were
unable to measure the metal substrate temperature during
resistive heating. This measurement would give a good
indication of the actual boundary layer temperature during
heating. We were also unable to generate enough product gas
during the timeframe of interest to permit sampling by gas
chromatograph, given our current bag sampling methods.
Details of the conditions of this testing are given in
Table 3.
We constructed two separate circuits for this
vaporizer/dissociator configuration; each resistively heated
element was powered by a 12-volt battery. We preheated the
vaporizer and dissociator simultaneously for 10 seconds prior
to fuel on. The fuel was then allowed to flow through the
heated system for an additional 10 seconds (total heating time
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Table 3
Sinqle/Dual-Staae Configuration Evaluation
Variable
Specification or Result
No flowrate
No N2 gas used
Battery voltage
12 volts
Voltage across monoliths
9 volts
Current to monoliths
300 amps at start of heating,
230 amps at finish
Heating scheme
Heat for 10 seconds prior to
fuel on; heat for 30 seconds
after fuel on
Fuel to injector
25 cc over a period of 30
seconds
Key on
Key on after 20 seconds of
heating (fuel on for 10 seconds
prior to start)
Gas Temperatures:
Fuel into single-bed
unit (liguid)
70-72°F
Midbed gas temperature
(dual-stage unit)
Approximately 400°F at fuel on
136°F at 10 seconds after fuel
on
Gas out of dissociator
130°F at end of test
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20 seconds). The product gas was piped to the engine through
the EGR port as mentioned in the discussion of the single-bed
unit evaluation. A cold start was then attempted; the engine
started immediately, without hesitation. Repetition of this
test without resistive heating gave the same result as in the
single-bed evaluation; the engine refused to start after
repeated cranking.
At a voltage drop across a heated substrate at 9 volts and
a current of 300 amps, power at 2700 watts is generated.
Assuming that heat transfer from the heated substrate to the
methanol fuel occurred at maximum efficiency, the power
requirement of roughly 2500 watts for dissociation would appear
to have been exceeded with the single-dual bed configuration.
Gas temperatures out of the dissociation reactor suggest
however, that dissociation did not occur (product gas
temperatures in excess of 400°F were not recorded).[7] At 230
amps, power output falls to approximately 2000 watts.
Obviously, dissociation becomes much more difficult at a lower
power output assuming heat transfer to the methanol is not
improved.
Heat transfer to the surroundings and the catalyzed,
nonresistively heated element in the dissociator may account
for significant heat losses in the 30-second timeframe of
interest. The engine started and idled without hesitation when
the monoliths were resistively heated, however; the cold start
assist may have been provided by vaporized methanol.
Several ways to assist the dissociation reaction with this
technology are now mentioned. First, a platinum/palladium
mixture may not be an optimum catalyst with which to coat the
resistively heated substrate. An optimized low temperature
dissociation catalyst could.be on technique to minimize the
reactor power requirement. Second, the metal foil bed may not
be of sufficient size to provide the amount of energy required
over the short time period of interest. A larger heated
monolith may provide additional reaction surface area. The
rectangular brick may not be the optimum shape for this
application; the fuel injector may distribute the fuel very
unevenly across the surface area, causing puddling and hot
spots to occur. A cylindrically shaped unit may be a better
geometry. Though we insulated the vaporizer and dissociator
housings with ceramic fiber insulation, a considerable amount
of heat transfer (therefore energy loss) may be occurring with
the surrounding air. This condition was also probably
aggravated by the location of the dissociator approximately 3
feet from the engine EGR port. Finally, a very large amount of
energy may have to have been transferred from the hot vapor to
the catalyzed, unheated monolith in the dual-stage dissociator
to bring this bed to catalytically active temperature. An
improvement on the dual-bed configuration may be the use of two
single-bed resistively heated monoliths. The first would be
used to vaporize the incoming methanol feed stream. The second
bed, located downstream, would be catalyzed and would serve as
a resistively heated dissociator support.
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VII Future Effort
Our immediate plans for future efforts with this
technology in the methanol dissociator cold start assist
application concern:
1. Additional energy provided to the fuel ahead of the
dissociation reaction; and
2. The use of a more appropriate methanol dissociation
catalyst.
We are procuring a Bosch flame glowplug capable of burning
fuel at a volumetric rate of 290 cc/minute. This hardware will
be mounted ahead of the catalyst to superheat the vaporized
methanol.
We are evaluating a noble metal/rare earth methanol
dissociation catalyst formulated by Nissan Motor Corporation.
This catalyst may provide a significant yield at lower
temperatures; if the initial evaluation of this catalyst is
successful, we will try to have the resistively heated* metal
monolith substrate coated with this formulation.
W. R. Grace has agreed to provide EPA with a base metal
formulation for use as a methanol vehicle catalyst. This
catalyst will have been applied to a resistively heated
substrate. We will test this formulation as a potential
dissociation catalyst when it is received.
We are also requesting Camet to supply EPA with a
platinum-catalyzed single-bed unit for use as a dissociator.
This unit will eliminate the catalyzed, but unheated bed in the
dual-bed configuration that may have been causing the vaporized
methanol to condense or cool to a lower, inactive temperature.
This unit will be tested together with the single-bed
uncatalyzed vaporizer.
VI11. Acknow 1 edojnent s
The catalyst used in this test program was supplied by
Camet, located in Hiram, OH. Camet is a manufacturer and sales
agent for W. R. Grace and Company. The test engine was
supplied by the Nissan Motor Corporation.
The authors appreciates the efforts of James Martin of
ECTD who served as the primary technician and greatly assisted
in this work.
In addition, the author appreciates the efforts of
Jennifer Criss and Marilyn Alff of the Control Technology and
Applications Branch, ECTD, whose cooperation and able
assistance during the preparation of this report, tables, and
figures was greatly appreciated.
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VII. References
1. "Development of Methanol Lean Burn System," SAE
Paper 860247, Katoh, K. , Y. Imamura, and T. Inoue, February
1986.
2. "Interim Report On Durability Testing of Low Cost
Catalysts For Methanol-Fueled Vehicles," EPA/AA/CTAB/TA/84-4,
Wagner, R. and L. Landman, August 1984.
3. "Using Methanol Fuels in Light-Duty Vehicles," SAE
Paper 872071, Brown, D., F. Golden, E. Gons, R. Potter,
November 1987.
4. "Unassisted Cold Starts to -29°C and Steady-State
Tests of a Direct-Injection Stratified-Charge (DISC) Engine
Operated On Neat Alcohols," SAE Paper 872066, Siewart, R. and
E. Groff, November 1987.
5. "Evaluation of Coloroll Methanol Dissociator For
Cold Start Assist Application," EPA/AA/CTAB/87-08, Piotrowski,
G., December 1987.
6. "Resistively Heated Methanol Dissociator For Engine
Cold Start Assist - Interim Report," EPA/AA/CTAB/88-02,
Piotrowski, G., March 1988.
7. "Decomposed Methanol Workshop Report," U.S.
Department of Energy, Windsor Ontario Meeting, June 9, 1983
(published October 1983).
8. "Engine Cold Start with Dissociated Methanol,"
Greiner, L. and E. Likos, Proceedings of the Third
International Symposium on Alcohol Fuels Technology, May 29-31,
1979.
9. Dissociated Methanol Fuel Requirements to Start A
Four-Cylinder Engine, Memo from Gregory K. Piotrowski,
OAR/OMS/ECTD/CTAB, Ann Arbor, MI, 1986.
10. Private Communication, Karpuk, M. E., Technology
Development Associates, Inc., to U.S. EPA, 1987.
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A-l
APPENDIX A
RESISTIVELY HEATED METAL MONOLITH DISSOCIATOR
SPECIFICATIONS AND POWER REQUIREMENTS
Construction
Dual-bed element composed of
two metal monolith catalysts,
a smaller resistively
beatable one and a larger one
with no provisions for
resistive heating
Catalyst material/loadings
Platinum/palladium;
proprietary
Shaue
Rectangular
Overall outer dimensions
(excluding mounting flanges)
10-3/4" X 4-1/4" x 2-3/4"
Length: flange to flange
14-3/4"
Heated brick dimensions
3" x 4-1/4" x 2-3/4" (approx)
Unheated brick dimensions
4" x 4-1/4" x 2-3/4" (approx)
Power supply
12-volt automotive battery
Current delivered to dissociator 300-230 amps at 10-11 volts
Heatup time to 600°F
with no gas flow through
the converter
Less than 20 seconds from 70°F
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B-l
APPENDIX B
TEST ENGINE SPECIFICATIONS
Manufacturer
Nissan Motor Company, Ltd.
Basic engine designator
CA18E
Displacement
1809 cc
Cylinder arrangement
4-cylinder, in-line
Valvetrain
Single, overhead camshaft
Combustion chamber
Semi-spherical, 2 spark plugs per
cylinder
Bore x stroke
83 mm x 83.6 mm
Compression ratio
Compression pressure
Fuel control system
11.0
17.0 kg/square cm (350 rpm, 80°C>
Electronically controlled fuel
injection
EGR
EGR not used
Valve clearance
0.30 mm HOT, intake and exhaust
Idle speed
Engine oil
700 rpm
Special formulation supplied by
Nissan for methanol engine
operation
Fuel
Ml00 neat methanol
Engine cranking speed
240 rpm
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