Re: Aircraft emissions techie question

Date:         10 Feb 2000 05:03:49 
From:         calburton@aol.com (Cal Burton)
Organization: AOL Canada http://www.aol.ca
References:   1
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In article <airliners.1999.1243@ohare.Chicago.COM>, Clunk <bernhard707@bigpond.com> writes:
>Jack Pease wrote:
>> Why is SO2 considered irrelevent when if you plug in SO2 into the UK
>> national emissions database (http://www.aeat.co.uk/netcen/airqual/naei/ )
>> do you get two dirty great red splodges over Gatwick and Heathrow? Where
>> is this SO2 coming from, given that avgas is a light distallate??

>SO2 emissions are a function of the oil refineries perfromace not the engine
>manufacturer.

Certainly refiners' performance in removing sulphur from fuels has a
direct bearing on SO2 emissions, which is what I believe Mr. Zunk
alluded to.

In any event, I just want to point out that "avgas", aviation gasoline,
is the fuel that powers aircraft piston engines.  It is extremely low in
sulphur content due to its manufacturing process (something to do with
alkylation units abhoring sulphur).  Moreover, the volume of avgas
combusted near Gatwick and Heathrow must be considerably less than the
volume of turbine fuel.  Jet A1, on the other hand, is a middle
distillate fuel likely burned in much higher quantity around these
airports.  It also has a considerably higher sulphur content, which can
vary from refiner to refiner, according to the manufacturing process.

Whether or not aviation sources are considered in the study, as stated
by Mr.  Felton in a previous post, I was not able to confirm by a quick
look at the URL.  Not sure I understand, though, how the aviation sector
could be excluded when measuring SO2 content near major airports.

Cal
(new to this newsgroup & thread, not a "techie", and not a Brit)