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Larry

wrote in news:m4p4e354ggmshgch6l42g4gutlpd5g19u0@
4ax.com:

Explain that again in one syllable words for me :-)

As I understand what you are saying you mean to remove the present
water cooled exhaust manifold from the cooling system and replace it
with a heat exchanger device to heat what? Water to make steam or oil
to heat water to make steam? Or did I miss something there?

To BOIL, not heat, seawater into steam...while still flushing the
manifold with a tiny bit of seawater to carry the salt, biologicals and
pollutants overboard at 212F. I want to turn the exhaust manifold into
an evaporator, just like the big ships USED to have before RO. The water
in the exhaust heat exchanger would have a controlled flow of seawater
into it to A) maintain boiling temperature while B) flushing out the
remnants overboard, self flushing evaporator, which isn't new.

In addition, I want to replace the antifreeze in the water jacket with
transmission fluid, or any free fluid that has a higher boiling point
than water like transmission fluid, that must A) not boil, itself, other
than at the head like the antifreeze does, now...and B) transfer higher
than 300F heat to a secondary heat exchanger, another boiler heated by
the coolant, not exhaust gasses, to boil even more seawater in a
secondary self-flushing boiler. Both these steam outputs would go to
one, or if necessary two, stainless steel condensors that look exactly
like the pipe-in-a-pipe freon condensors on a marine air conditioner,
which is very compact. This condensor would have a seawater jacket
around the central stainless steel steam pipe it cools, dumping the heat
of condensation into the hot water tank heat exchanger before dumping
excess heat overboard. The condensor only need be pulled apart far
enough so that gravity will drain the distilled water out of it at your
worst angle of heel so it doesn't vapor lock...and be mounted above the
engine far enough so only steam can reach it from the gas outlet of the
various boilers below.

A power boat wasting millions of Btu/day would sink from fresh water
flooding if this thing were left tanking it all. Being as the distilled
water output from this contraption were HOT water, not cold as with RO,
you might even be able to just tank it for that hot shower, directly.
The water coming out of my steam condensor will burn you at 200F. To get
a cold drink, you'd have to cool the engine distiller's water before
drinking it....maybe with further seawater cooling, which is plentiful.

There's so much great heat just going up the stacks and running out of
the boat from the seawater indirect cooling systems on these monsters
it's pitiful! Heat is POWER! All it needs is useful conversion. I've
never figured out why a big power boat doesn't have a Stirling genset
running off its waste exhaust heat, alone! God, it's certainly hot
enough with enough Btus.

The reason I ask is because many years ago I maintained a distillation
plant that used exhaust heat to make steam. If I remember correctly
the primary power was a Perkins 4-108 diesel and it didn't make enough
exhaust heat to boil water at sea level atmospheric pressure. The
distillation vessel was heated as hot as possible using the exhaust
and then an engine driven vacuum pump dropped the pressure in the
still to create steam at temperatures lower then 212F.

It's not? That's most interesting. Maybe we should put the fluid
coolant heat exchanger AFTER the exhaust heat exchanger and use the
exhaust heat as a pre-heater if that's so. Anyone who forgot to open
cooling water thruhull valve KNOWS how much heat and steam the water
jacket can make! Hell, we're only using 30-35% of the energy in the fuel
we're paying $3.50/gallon for, now. The rest of it goes overboard as
waste heat.

Pulling a vacuum on the boilers is also an excellent idea that's been
used since the 1800s, or maybe even before to reduce the boiling point.
I was trying to keep this as simple as possible and free running into
current water tankage.

I wonder why that system allowed all that water jacket heat that's so
hard to get rid of to boil even more seawater?

Whether this was done to increase thruput or because exhaust heat
alone was not sufficient I do not recollect.

In any event, given the cost of reverse osmosis systems using engine
heat would seem rather attractive.

And any RO uses more power which equals more fuel expense we can no
longer afford. It's a shame to let so much heat just blow out the stacks
and be poured overboard as hot seawater when there are so many uses for
it....like distillation, heat engines driving gensets, etc.

-----------------------------------------------------------------------

I love things like this. When I was using my little 1KW Honda EU1000i
genset to power the service van, I noted that its tiny exhaust was
exiting separately from its air cooling exhaust. So, I welded a pipe
nipple to the engine exhaust so I could pipe it where I wanted it. The
exhaust gas and cooling air exhaust come out on the same end through some
plastic louvers.

The truck is cold in winter with only a small engine heater for the
driver. The back was always cold to work in. So, I moved the tiny
genset from its mount outside the rear door to inside the back of the
"cabin" and used some flexible natural gas pipe, stainless steel with
external ribs that would act as a radiator, made into a big loop behind a
cabinet where there was a void open to the cabin air. The exhaust heated
the tubing, the tubing heated the air, what came out was really HOT air
wafting up from behind the cabinet. The cooled exhaust gasses went
through a hole in the deck to be vented to atmosphere below the truck's
floor. Exhaust gas is heavier than air, so it vents away from the cabin
and this also drains the water vapor that condenses in my heat
exchanger...it runs a full stream, suitable to fill my PortaPottie! The
exhaust gas is about 75F coming out...a good exchange of heat. Because
the genset is INSIDE the cabin, all of the waste heat coming out of its
air cooled engine is POURING out onto the deck of the cabin. I'm
recovering around 98% of all waste heat. When it's 30F outside the
poorly-insulated truck box, I can make it 80F inside in an hour!.....and
have up to 1KW of electrical power, 120VAC 60 Hz to power the shop. The
noise was awful...so I built a foam cabinet out of 4" thick foam packing
crate foam I got for free. The cabin air intake to cool the engine goes
through a little foam muffler on the intake end. The exhaust gas heat
exchanger and cooling air outlet goes through yet another foam muffler I
built onto the other end...making it amazingly more quiet.
Voila!...Gasoline heater and genset! You wouldn't want to live with
it...but it sure is nice trying to work on a cold day in January where
it's WARM as Toast!...(c; After all, old cars had exhaust gas heat
exchangers heating the cars back in the early part of the 20th
Century....not hot water heaters which came later. 1 gallon of gas
provides electrical power and cabin heat for all day....(c;

Larry
--
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The ultimate dirty bomb......