[Gasification] Condensing heat exchanger

[Steve Carroll]

I'm praying for extremely good combustion.  What do
you think will be in the condensate?  Could it be
pretty toxic?

I don't know if I would try to cool the exhaust stream
with a direct spray of water.  Maybe some one else has
actual experience?  Saturated air at 122°F (50°C) has
a moisture content of 608 grains per pound of dry air.
 It seems like you might be losing more energy than
you recover.  You might still be able to recover it if
you pass though another heat exchanger to preheat
combustion air from outside.

I like the idea of trying to neutralize the acidity. 
I might try an experiment in our sink.  sometimes if
you leave something in a wet stainless sink it will
leave a rust spot.  I'll have to see if leaving a
piece of drywall in a wet sink does the same thing. 
If not, then we're in luck.

I don't know how nasty the water would be or could be.
 Myabe it can be filtered and the filters can be sent
to a land fill or incinerated.

Thanks,
Steve

--- AJH <list at sylva.icuklive.co.uk> wrote:

> What will you do with the condensate? I don't think
> you'll get it
> clean enough to discharge unless you have extremely
> good combustion.
> 
> I'll throw a few thoughts into the pot because I've
> been looking at
> this, mainly to do with burning wet wood.
> 
> I was looking for simplicity and low cost, so my
> thoughts were on the
> lines of an water filled,insulated, plastic barrel
> under the flue with
> a stainless steel plate heat exchanger near the top
> and under the
> water level. The water for an underfloor heating
> system runs through
> this plate heat exchanger constantly, hopefully with
> a return <25C.
> Water drawn from the bottom of the barrel is pumped
> up in a fine spray
> into the vertical flue, this spray then condenses
> out any water vapour
> in the flue gas and cools it to somewhere around
> 50C, obviously the
> remaining flue gas is saturated at this temperature.
> We'd need to look
> up a psychometric chart to see how much water was
> being lost this way
> but I expect it to be around 30 grams per cu metre.
> 
> At the bottom of the barrel some loose rocks of
> chalk or broken
> concrete, to neutralise the acidity. An overflow
> pipe from the bottom
> led up the outside to a level just above the heat
> exchanger to
> discharge. I am almost certain that this arrangement
> would not pass
> environmental limits for discharge into a water
> course in UK.
> 
> Andrew Heggie ( follower of Heath Robinson ;-))
> 
> 
> 


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com