[Gasification] engines

[Peter Singfield]

The old steam systems that stored heat energy were fire tube boilers. With
build in large reservoirs of water.

These are limited to how high pressures can go -- 350 F is about maximum.

And as such -- very low steam efficiencies -- much less than 5%

Now -- if you took the saturated steam from that kind of boiler and fed it
to an ORC -- your running in style --

But then -- why not sub thermal oil for the steam/water -- zero pressure --
no pressure vessel rules to meet -- and no need for a licensed steam boiler
operator -- the same fire tube boiler -- operating at 400 F -- or 450 F --
and 15% and better over all efficiencies.

Plus -- easy to recover waste heat. The condensers from the ORC blow it off
as hot air -- but if you prefer -- convert that to heat for your hot water
heating system.

Peter / Belize


At 07:25 PM 2/10/2007 -0000, Ken Boak wrote:
>Geoff, Toby and List,
>
>That looks like a very well constructed conversion, with a lot of thought 
>put into it.
>
>Using the pistons as cross heads, lubricated by the original engine lube 
>system is definitely the way to go.
>
>An enterprising foundry could offer castings for the cylinders to make the 
>conversion, as well as pre-machined plates for the "blanking plate" and the 
>cylinder heads.
>
>Toby's idea of storing energy in steam, in order to reduce the variations in 
>gasifier output is a good one.
>
>A monotube boiler with a fat storage section, might be one way to proceed.
>
>Of course gasifier/steam plant suffers from none of the problems associated 
>with gas cleaning, cooling, tars etc.   It also generates a huge amount of 
>waste heat in the form of hot water which would be ideal for domestic 
>heating.
>
>How about a gasifier home furnace with close coupled steam engine and 
>generator? About the size of a large domestic furnace and spinning a steam 
>engine at up to 600 rpm.
>
>Couple the steam engine shaft directly to a permanent magnet alternator 
>(PMA) intended for a slow speed wind turbine, and the accompanying 5kW to 
>20kW grid-tied inverter.  A simple package available off the shelf from 
>China:
>
>www.ginlong.com
>
>I have it on good authority that the volume prices of the 5kw inverter is 
>$3000 and the 5kw PMA is $1280
>
>
>You might want to have a look at this 20hp engine from Mike Brown Solutions
>
>http://www.mikebrownsolutions.com/20hpse.htm
>
>He also produces a 1hp single and a 3hp twin engine, which might be more 
>appropriate for the smaller property - browse his site for details.
>
>These engines are quite inefficient - roughly 5% efficient for the 
>electricity, so expect a lot of heat and only modest amounts of power . For 
>example - for the 3hp,   29kw of heat and 1.5kW  of electricity. But well 
>suited to the typical home.
>
>With wood gas you have a more controllable fuel than fire wood,  a simple 
>diverter valve would direct the woodgas to the furnace heat exchanger, 
>rather that the steam monotube boiler, when temperature and pressure were 
>reached -allowing simple control of the steamboiler and diverting excess 
>thermal energy to the furnace and domestic heating.
>
>
>Ken
>
>
>