Blending diesel with E-85 or straight ethanol?

[markrinker]

Would E-85 or straight ethanol blended (in small proportions) with #2 diesel aid in cold weather starting and injector cleanliness?

I have heard of people in cold climates blending small amounts of gasoline during cold weather, but never ethanol.

Up here in the north country, they sell 'Arctic Diesel' - was wondering if anyone knows what it is that they add to the fuel to give it better flow and anti-gelling characteristics?

[damork]

Mark,

Any amounts of alcohol or gasoline are off limits for diesels as the components in a diesel fuel system are not designed to work with them. I wouldn't risk it, I've seen the damage done to fuel components where gasoline mistakenly was added to diesel.

I worked for 3 years around Prudhoe Bay Alaska and we always ran Arctic Diesel, fresh from the refinery that used crude from pump station #1 on the Alaskan pipeline. It looks as clear as water, and is very dry. The waxes that normally appear in #2 are refined out of it to allow it to flow at low temps. We had more than average trouble with sticking injectors in Detroit Diesel engines (53, 71, and 92 series) and some trouble in Cat 3208 engine fuel pumps (Sleeve metering pumps).

We started adding oil to the fuel tank to provide some lube, and during those times we simply didn't know much about diesel fuel lubricity.

[markrinker]

My question is more theoretic that practical. One website that I researched describing 'Arctic Diesel' mentions that an additive is blended to #2 diesel. This sounds different than the additional refining you mentioned.

Theoretically - would alcohol increase or decrease lubricity? Would alcohol increase or decrease gelling?

[moondoggie]

Good Day!

I think ANY ethanol would be an emulsifier, which is a big no-no. Our diesels are only supposed to use demulsifiers, which will allow the water separator to do its job - the water is NOT supposed to get past it to the IP.

Hopefully, more knowledgeable heads will chime in here where I've gotten it wrong. :D

Blessings!

Brian Johnson, #5044

[markrinker]

Found an article that addresses the idea - again, I am interested in THEORY only, and not suggesting anyone try this on their 6.5!!!

.0 ALCOHOL- DIESEL BLENDS (DIESOHOL)

Apart from ethanol/methanol-gasoline blends, ethanol/methanol-diesel blend is also another alternative option. Ethanol-diesel blend projects are under trial in Brazil and Sweden. Unlike ethanol-gasoline blend, ethanol-diesel blend has some concerns regarding lubricity, reduced flash point and startability problems.

3.1 International Experience:

Several technologies are currently under trials in different parts of the world. An Australian non-profit organization APACE has developed a ethanol-diesel emulsion agent which is under trial in Australia. Thailand, Chile, Malawi, Germany and Sweden. This diesohol technology claims successful blends up to 15% of ethanol in diesel. APACE claims that this emulsion, which allows use of hydrated ethanol with diesel, gives improvements in NOx, PM including PM2.5, hydrocarbons and also increases the thermal efficiency of the engine. Vehicles can use diesohol and diesel fuels interchangeably. The fire point of diesohol is higher than flash point and the magnitude of the difference depends upon the composition of the diesel fuel. Australian Government is currently in the process of developing fuel quality and operability standards for dieshol.

There are still several issues that need to be resolved before diesohol can be introduced commercially, some of the important issues are:

- Vapour lock-use of ethanol changes the vapour lock characteristics of the fuel.
- Material compatibility of pump seals, timing belts and some nitirle rubber seals used in the fuel injection systems of a vehicle is still a concern.
- Toxicity of the emulsifier.
- Dosage quantities of the emulsifier which may vary from base fuel to base fuel.
- Blend stability, especially at low temperature.
- Establishment of diesohol test standards.
- Stability under water addition.

3.2 Indian Initiative on Diesohol:

It is interesting that India was one of the earliest countries to recognize the merits of burning ethanol in diesel engines. The bi-fuel system developed by a German Professor H.A. Havemann & his colleagues at the Indian Institute of Science (IISc), Bangalore, in the early 50's is the earliest original published work in technical literature regarding alcohol diesel.

Government of India has sanctioned Rs. 4 crores for R&D studies on ethanol-diesel blends. MoP&NG is also working on to introduce 5% ethanol-diesel blend. For this purpose Indian Oil Corporation has selected some vehicle models to carry out trial tests on these vehicles. IOC (R&D) has also recommended SIAM members to carry out the tests trials with 5% ethanol-diesel blend, which are to be supplied by IOC. However, as on date BIS specification does not permit blending of ethanol and diesel.

Sufficient field trials in Indian conditions need to be carried out and its benefits on emissions, material compatibility and drivability, etc. may be assessed before trying this fuel in India.

There are some field trials data on methanol-diesel blends. IIP has developed a retrofit kit for dual-fuel operation of diesel vehicles with alcohols. IIP used the fumigation concept for this purpose and successfully demonstrated this system on MSRTC and DTC diesel buses under actual commercial passenger service. The fleet consisted of 25 & 35 buses of Tata and Ashok Leyland respectively with a total cumulative operation of 42,00,000 kms. The methanol fuel consisted of 10% gasoline also; to impart flame luminosity from the safety angle as the methanol flame is almost invisible in sunlight. The findings of the study are tabulated in Table-3.

Table-3: Results of IIP fleet study on Methanol-Diesel Blend
Number of Buses
60 Numbers

Total Operation
42,00,000 kms

Diesel Replacement
15-20%

Fuel Consumption
Comparable

Energy Efficiency
Better

Smoke Reduction
25-40%

Drivability
Good-to-Better

Oil Consumption & Degradation
Comparable

Engine Wear
Lower-to-Comparable

Engine Deposits
Lower-to-Comparable

Sludge Deposits
Marginally Lower

Material Compatibility
Adequate. Rubber components partially hardened


From the above work it was concluded that 15-20% substitution of diesel by alcohols is possible by a simple retrofit fumigation system. Even though more field trials are required on new generation diesel engines to assess the technical feasibility of the fuel.

[ 10-11-2004, 02:57 PM: Message edited by: Mark Rinker ]

[DmaxMaverick]

While small amounts of gasoline (less than 10%) will normally cause no damage or appreciable decrease in performance, it will decrease the lubricity of #2 Diesel to some degree. This is the old rule, and the jury is still out on the newer fuel injection technologies in use today.

Arctic Diesel is as described above. Higher refining processes remove the properties of the fuel that cause gelling and waxing. #2 Diesel with additives, or mixed with #1, is just "winterized" Diesel.

Alcohol, on the other hand, is an absolute no, for several reasons. Combustion properties are the least of the concerns, as concentrations won't likely be enough to cause significant changes.

As stated above, water absorbtion is the main reason. Alcohol will not only emulsify water into the fuel, it will also absorb water out of the atmosphere and emulsify it into the fuel. While this is not a major concern in the "emulsify is good" camp (water emulsification, not the use of alcohol), the problem doesn't stop there. As temps and pressures change, so does the moisture absorbtion properties of the alcohol. As temps change, the water will condense and drop out of the alcohol, creating free water. All the while, the alcohol on the exposed surface will continue to absorb atmospheric moisture. It will continue in a process that will only stop after the alcohol has been either consumed, or vapored off into the atmosphere. If alcohol is maintained at a constant temp, it will reach a point of saturation, and take on no more water. Colder temps will prolong the process, as the alcohol vapors at a much slower rate. The result is the water left behind. The process is complex, but that's about as simple as I can explain it.

The second concern of the alcohol is corrosion. Much of the components in our fuel systems are aluminum. Aluminum is extremely sensitive (compared to many other metals) to the corrosive effects of alcohol. This is due to the alcohol's ability to seperate a lubrication element from the surface of the metals. In effect, a lubricating film usually present on internal components will be displaced by a film of alcohol. This also leads to errosion and scoring. This is why alcohol makes such an effective solvent. If you need to clean oil from a floor, add some alcohol to your mop water. Works wonders.

Alcohol is nearly infinitely resiliant. It won't stop its process. It has to go away, one way or another, before the process stops.

I have heard of the research(s) underway with emulsified alcohols, but they would have to come up with a way to "buffer" the alcohol from the fuel and atmosphere, such as encapsulation. That's probably the trade secret, if it exists. More power (not Jim) to 'em, if they get it to work.


On edit:
Just did some figuring on the above posted study results. If you meant 42 million (posted was 42,00,000) total Km's with 60 buses, that would be an average of roughly 427,000 miles each. That's hardly believable. If you meant 4,200,00 KM, it would translate to about 42,000 miles each. That would be a more reasonable study result.

[kowsoc]

Why not use a fuel additive with anti-gel and cetane improving properties? I have used some that claim a drastic improvement in gel point. Cetane is a rating on the self ignition quality of the fuel....higher cetane means easier ignition so cold starting will improve.
My .02 ;)

[markrinker]

Thanks for all the informed replies. Sounds like alcohol will only be used as a gasoline additive anytime soon. Too bad, I'd like to see our dependance on foreign oil decrease, but don't think the current bio-diesel initiatives are much more than a farm subsidy.