6 replies to this topic

[Gerrit]

Hi,
I would like to introduce myself, I'm from the Netherlands.
Currently out of work and starting my own business.

Reading this site many questions arise, as I'm trying to understand the GEK gassifying process.

My goal is to use a GEK, to power generator sets for commercial use, like the ones that are now powered by a, say, 175HP diesel engine.

First question: What would be a better idea, use the gas to fire a boiler for a steam engine, or modify a gasoline engine, to run on the gas?

Absolutely delighted that I stumbled across this site!

Gerrit

[allyn]

Experimenting with converting a 175hp gasoline engine to run on producer
gass is not so scary.  Experimenting with a boiler large enough to provide
175hp worth of steam,  very scary indeed.  I'm assuming you would be
building the boiler yourself as it would be cost prohibitive to purchase
one for a project that may or may not be comercially viable.

Allyn

[larrymaden]

Any 175 Hp ICE would not have 175 'taxable' horsepower, as would the 175 Hp steam engine, so you would be comparing apples to oranges.
Any dynamometer-rated 175 Brake Horsepower Diesel engine would have no more than 80 Maximum Taxable Horsepower.
So, the proper comparison would be with an 80 Hp steam engine.
Any dynamometer-rated 175 Brake Horsepower gasoline engine would have no more than 65 Maximum Taxable Horsepower.
Steam piston engines, boilers and condensor systems designed and insulated for maximum thermal efficiency can be as much as 95% thermally efficient.
An average Diesel ICE achieves around 45%, and a gasoline ICE about 35%, while the very best steam turbine systems cannot yield 50% TE.
In addition, the low speed of steam engines yield a much longer useful life than the high Rpm's of ICE's. The longer the stroke and lower the Rpm's with the least possible gearing loss the better.
Building a very tall (long stroke) vertical steam piston engine with an alternator built right into the flywheel with the proper number of poles to yield the 50 or 60 cycle electricity that you require, at rated speed, without any gearing would actually be the most efficient configuration.
If you need help to design such a system, on a commercial scale, contact me at lmaden@frontiernet.net with the size you desire.

[rutman]

Would there be any advantage to running a steam engine off gasifier gas, or could one simply burn combustibles for the heat to run a steam engine without bothering to gasify? A chemist colleague has pointed out that one is wasting some amount of energy in a gasifier by partially combusting (e.g. to CO2 and H2O) and then reducing back again  - thus gasification is used for cases where you don't have good transport for solid fuel like coal but do have gas pipelines, or need clean fuel e.g. for an ICE.  But in the case of a steam engine which according to your figures is highly efficient, clean fuel is unecessary, no?
jeremy

[jimmason]

this is correct jeremy.  it takes energy to gasify.  usually about 25-30% of the raw fuel energy value if you are not doing any waste heat recovery.  thus if you can direct combust fully and cleanly, you will usually have a higher efficiency at the combustion to heat stage.  what your efficiency from heat to mechanical and electrical outputs depends on a mess of other factors as you know.

we bother with gasification because we want to use solid fuel in applications that do not easily intake solid fuel.  like IC engines.  a gasifier and a steam engine with boiler is somewhat redundant.  but there are applications where such does make sense.

jim

[jason baptiste]

Gasoline engine ignition systems generally rely on a combination of a lead-acid battery and an induction coil to provide a high-voltage electrical spark to ignite the air-fuel mix in the engine's cylinders.

[mcstar]

Jim,
I'm curious if you've been able to measure the total thermal efficiency of your GEK with the Tower of Total Thermal Inegration?  The earlier comments that energy is wasted in the burning process while partially true, ignore the fact that the real losses are due to heat energy escaping the system.  If the heat loss from the GEK could be contained through insulation, you could expect to get your energy losses very low, maybe even approach >80% end to end.  Let me explain how.  

First, insulate everthing.. if it's warm to the touch it needs more layers.
Second -- Recover every once of thermal loss from the prime mover.   You've already started this with the done this with the exhuast re-circ, very good idea!  Now inuslate the heck out of the juncition.  
Then,  about 20-30% of an engine's heat energy is released into the air... go water cooled, insulsate the engine, increase the flow rate of water through the engine, then setup the raditor to warm the air being drawn into the GEK.  

I used to work on a naval carrier as a reactor operator.  100% of the energy needs of the ship came from some very hot pieces of metal in the reactor core.  Our system was setup to transmit, contain and reuse as much of that heat as possible.   We had calculated thermal efficiencies of about 92%.  The cores on that ship lasted 30years before they had to be replaced.  If we had had the thermal efficiency of a gasoline engine, it would have only lasted 10 years!  I see the GEK + the TTTI as the first setup with the potential to increase the efficiency of a gasoline engine to > 70%.   If this can be accomplished, it would cut the wood consumption in 1/2.

I think it's very possible.  The steel pipes on our ship had 3000psi 600 degree steam running through them, but the insulation they were wrapped in was so effective, you could touch them and they only felt warm.