Removing Ethanol from Gas?

On 9 Aug 2006 11:27:58 -0700, "M" wrote:
I don't think there's nearly enough ethanol manufacturing capacity to
do a nation wide mix of E10. That's a huge amount of ethanol to be
made from corn or other plants, plus the cost and the energy in
distillation.

And more importantly, a waste of good corn liquor...

"Grumman-581" wrote in message
...
On Wed, 9 Aug 2006 10:12:00 -0700, "Al"
wrote:
On that hot day at high altitude, over an obstacle, which takeoff
performance chart do I use?

The one that says, "stay on the ground and have a beer"?

Ding! You win. This is of course the right answer. (and I like your style)

Al G

"Al" wrote in message ...
:
:
: There is also the issue of performance. As I understand it, alcohol
: doesn't produce as much horsepower per volume as does avgas. If I use a
: mogas that has alcohol in it, I don't have the "Get up and GO" that I used
: to have. On that hot day at high altitude, over an obstacle, which takeoff
: performance chart do I use?
:
: Al G
:
:

It is a power to weight issue. If you are pulling 28" at holding 2650 RPM, alcohol or gas it is the same power. You just
need to move more alcohol through the engine to do it. This is the primary reason there are special cars that can run
the e85 stuff - they have bigger carb jets so they can maintain the correct egr.

I suppose there would be issues on low pressure altitude days where and airplane engine may be starving for fuel (to
lean) if it is fed alcohol...

".Blueskies." wrote:

"... there are special cars that can run the e85 stuff - they have
bigger carb jets so they can maintain the correct egr.

What's a carburetor? (Asks the auto owner)

".Blueskies." wrote in message
m...

"Al" wrote in message
...
:
:
: There is also the issue of performance. As I understand it, alcohol
: doesn't produce as much horsepower per volume as does avgas. If I use a
: mogas that has alcohol in it, I don't have the "Get up and GO" that I
used
: to have. On that hot day at high altitude, over an obstacle, which
takeoff
: performance chart do I use?
:
: Al G
:
:

It is a power to weight issue. If you are pulling 28" at holding 2650 RPM,
alcohol or gas it is the same power. You just
need to move more alcohol through the engine to do it. This is the primary
reason there are special cars that can run
the e85 stuff - they have bigger carb jets so they can maintain the
correct egr.

I suppose there would be issues on low pressure altitude days where and
airplane engine may be starving for fuel (to
lean) if it is fed alcohol...

So, I just run it richer? Or, in the case of a departure, where the
mixture is already full rich, you're saying there will be NO loss of
performance by using a mixture of autogas and alcohol?

Al G

"Al" wrote in message
...
So, I just run it richer? Or, in the case of a departure, where the
mixture is already full rich, you're saying there will be NO loss of
performance by using a mixture of autogas and alcohol?

No, what he's saying is that if full power with regular gas is 28" at 2650
RPM, then you aren't going to see 28" at 2650 RPM using alcohol or a blend
of alcohol.

In theory, you could calculate the actual percentage horsepower (it will be
less than 100%) based on what RPM you do actually get for a given throttle
setting, and then use a density altitude chart that matches the horsepower
you're actually getting (the chart will actually be slightly conservative,
because you will only have reduced power, rather than all of the negative
effects of high density altitude).

But it seems to me that if an airplane has been certified for use with
alcohol or a blend, it should have the necessary charts for that type of
fuel anyway. If it's not certified for that use, then operating the
aircraft that way wouldn't be advisable in any case, even if you could
determine what power you're getting from the fuel and translate that to a
correct chart to use.

It's good to know what to do in an emergency if you just HAVE to use the
wrong fuel, but just because you can determine the actual performance, that
doesn't mean there aren't other reasons to avoid the fuel.

In other words, this is an interesting academic exercise, but you and -581
had it right in your other posts. Staying on the ground is the correct
day-to-day answer.

Pete

Couple of questions I don't see being addressed:

1. If regular mogas is 80/87, like it says on the pump, and you take
out the octane booster (alcohol), what is the octane rating of the
remaining gas?

2. How do mid-grade and high-test achieve their octane ratings? Do
they just add more alcohol?

What I'm asking is, if your engine is rated for 80-octane, and you
reduce the octane rating below that by taking out the alcohol, is that
a good idea?

3. What is *in* that non-alcohol gas in Iowa now that boosts its
octane? TEL? MTBE? Nitroglycerine?

Don

Everyone might drop in on Baylor U's flight research programs. The've
been flying numerous aircraft on everything from straight avgas to 100%
grain alcohol. They even have STC's for the O-235 and IO-540 series
engines to run on any percentage of ethanol. I know that one of the
prof's has been flying airshows in a couple of IO-540 powered bipes for
almost 25 years on staight 200 proof grain alcohol. Their research
should be able to answer virtually every question about running on
E(x)mogas

Craig C.

Don Tuite wrote:

1. If regular mogas is 80/87, like it says on the pump, and you take
out the octane booster (alcohol), what is the octane rating of the
remaining gas?

It depends on the ethanol blend. Ethanol itself is about 100 octane.
When mixed with gasoline at a ratio of 90:10, gasoline to ethanol, (E10)
it raises the octane of the mixture by about 2 to 3 octane points,
compared to the base gasoline.

2. How do mid-grade and high-test achieve their octane ratings? Do
they just add more alcohol?

Different refining of the gasoline as a base, then the addition of
ethanol to boost it the final amount.

What I'm asking is, if your engine is rated for 80-octane, and you
reduce the octane rating below that by taking out the alcohol, is that
a good idea?

No. You should start with a higher octane rating mixture before removing
the ethanol.

3. What is *in* that non-alcohol gas in Iowa now that boosts its
octane? TEL? MTBE? Nitroglycerine?

Iowa hasn't used MTBE for many years. Ethanol was its replacement, and
pretty well any automobile engine is allowed to use a mixture of up to 10
percent ethanol.

Avgas and mogas are rated/tested by different methods and
standards.



"Don Tuite" wrote in
message ...
| Couple of questions I don't see being addressed:
|
| 1. If regular mogas is 80/87, like it says on the pump,
and you take
| out the octane booster (alcohol), what is the octane
rating of the
| remaining gas?
|
| 2. How do mid-grade and high-test achieve their octane
ratings? Do
| they just add more alcohol?
|
| What I'm asking is, if your engine is rated for 80-octane,
and you
| reduce the octane rating below that by taking out the
alcohol, is that
| a good idea?
|
| 3. What is *in* that non-alcohol gas in Iowa now that
boosts its
| octane? TEL? MTBE? Nitroglycerine?
|
| Don