Author Topic: CH4  (Read 15299 times)

justsomeguy

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CH4
« on: January 22, 2006, 09:20:48 PM »


How about natural gas?


A diesel engine won't run on 100% nat gas, as its octane is too high, and it won't self ignite.  However, a little shot of diesel will ignite, and makes a great "spark plug" for the natural gas/air  charge.  Again......... a local light plant with old Fairbanks-Morse engines does this.  They start and warm up their engines on diesel, grid tie them, and then turn on the gas, and run them on  90-95% natural gas, with 5-10% of the power coming from the drastically decreased diesel as the "spark plug" ignition source.  The diesel smoke vanishes from the power plant stacks when they turn on the natural gas.

Is anyone running their Listeroids on 70-90% natural gas with the remaining 10-30% being fuel/waste/veggie oil for the ignition source?  With the increased talk of cogeneration and combined heat and power, natural gas is about 60% as expensive per BTU than number 2 fuel oil.  And it takes less effort than hunting/gathering WVO.   In a residential/light commercial/light industrial (heat the shop) environment where natural gas is available (already being used as a heat source?) it seems like burning it in an already grid tied listeroid would be a winning idea.  It also burns very clean.

Since they don't need to load follow, no fueling governor connection would be required for the nat gas in a grid tie situation.  Just pipe gas to the intake, and open the gas flow with a gate valve and adjust the governor (liquid fueling) to decreases to where the engine operates in a stable fashion on the minimal amount of liquid fuel.  Use an electric solenoid to shut down gas in event of loss of grid.  If the belt broke or the system was to island somehow, the engine wouldn't run away, because the governor would shut down the liquid fuel as the RPMS increased to the point where the natural gas would go through unburned.  (no liquid fuel = no 'spark' no burn, no power, no increase in RPMS.)  It might hunt quite a bit with excess gas, no mechanical load, and the liquid fuel turning on and off to maintain RPMs,  but at least it wouldn't destroy itself.

Stan

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Re: CH4
« Reply #1 on: January 22, 2006, 10:42:23 PM »
Hi there "just some guy" whatever your name is.  I"m going to rant here so be prepared.  First I'll explain.  I farmed for 7 years in Dawson Creek in the 80's (sheep, don't laugh).  I also hear people saying "natural gas" (an oxymoron by the way) is clean burning.  I say hogwash for 2 reasons.  Here's why.  First, when it comes out of the ground, it is most often in it's true form called sour gas.  Sour gas is so poisonous that often you aren't allowed withing 5 miles of a sour gas wellhead.  The gas is then passed through what is called a scrubbing plant.  These scrubbing plants are always located far from any urban area because if they were "discovered" by environmentalists, they would be shut down immediatelyl.  They spew heavy metals, poisonous gasses, lots of sulpher (which is what poisoned my farm) and and many many other bad bad things into the air which we will eventually breathe.  I was up in a Cessna one day in the spring and I noticed a "cone" of dead vegetation stretching 70 miles to the West (my farm was right in the middle of it) straight at what turned out to be a "scrubbing plant".  So on that point alone don't ever say natural gas is clean.  Maybe it is when it gets to the urban centers in the South, but it has poisoned the earth on the way.

The second point revolves around the age of the C02.  C02 in natural gas (and diesel too) comes from 200million yr old stored hydrocarbons that were laid down when the world was a very different place (I'm talking about the composition of the atomsphere, not the neighbours).  By unleashing these 200m yr old molecules of C02, we are trying to bring the atmosphere's composition back up to the levels it had way back then.  We don't want that.  Burning wood on the other hand, if it's done properly, is unleashing 100 year old C02 back into the atmosphere, not a problem.  Producing wood gas to use along with veggie oil is the way to go if you want to be environmentally clean NOT using so called clean, natural gas.
Stan
Sorry for the rant, you were warned up front. javascript:void(0);
Wink

Doug

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Re: CH4
« Reply #2 on: January 22, 2006, 11:28:26 PM »
No Wuckas Stan :

There is an alternative to squash dynosaur and veg that no one talks about called the Fischer-Tropsch process that covnverts flamable gasses from sources like large bi-mass fluid bed gassifiers that can provide a synthetic diesel fuel. Then there are some modern Imbert style gassifiers that could be used to provide producer gas for the engine from wood, or other dry biomass.

Now Here is the "but...." part of my post. As you scale this technology down efficiency goes down the toilet and it rquires a lot of opperator input to keep it running. And a small scale Fischer-Tropsch reactor, well I only sort of understand the concept of fuel reformation and I wouldn't know where to begin. The important thing to remeber is this is clean technology and could take some of the presure off bio-diesel vs food.

A simple gassifier for those interested has ben posted on the Internet by Doug Williams of Fluidyne Technology.
And the UN dep of Agriculture developed a technical paper on the subject of running Diesel engines on bio-mass gassifiers for transportation and power generation in the 80s that is alos available on the net. The Swedes and Fins have continued to develop this technology since the war as a back up plan in case they ever were cut off from oil¬  as they were from 1939 to 1945 and quite a lot of this info is covered in the UN papers.

It realy burns my back side to know that we spend no money at all on this technology in Canada

Doug

Here's link to some intersting info, note this old fellow seems to be using a version of the FEMA open top down draft gassifier by Harry La Fontaine. Also known as the "inverted trash can gasser", I wouldn't build one like this!!!!

http://www.clean-air.org/Ed%20Burton%20Story/wood_chips_to_bio.htm

Stan

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Re: CH4
« Reply #3 on: January 22, 2006, 11:58:29 PM »
Right on Doug....I burn wood pellets at $175 per ton.  The pellets are made from chipped waste wood with no binders in them at all.  The waste wood is chipped, mixed into a slurry, then forced through small holes (3/16" ??) at very high pressure.  The pressure heats the wood and loosens the natural binding material in the wood (cellulose) to bind it together into something that looks very much like rabbit food.  This stuff, although expensive, would be perfect for gassification.  It's dry, its waste and its easy to handle.  The cost is a bit of a bunger but if you factor in owning a truck just to get firewood, it makes it easier to swallow.
Stan

Doug

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Re: CH4
« Reply #4 on: January 23, 2006, 12:08:07 AM »
There is a fellow In Manatoba that is tryingto build a CHP(combined heat and power) system that runs on chipped wood.

Greg Manning
http://www.inetlink.ca/a31ford/cgcmb/old-default.htm

If you look closely you can see they system evolve from and inverted trash can, modfied Imbert with a lot of Fluidyne inspired mods..

Doug

Stan

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Re: CH4
« Reply #5 on: January 23, 2006, 04:15:28 AM »
Terrific site Doug.....They have started clearing (they call it "selective logging" but it looks more like clear cutting) around my town, Kimberley, which is a ski resort in the mountains of S.E. BC.  Instead of slash burning the piles of unusable trees (too small, etc.) they had to chip them with an enourmous wood chipper.  They had to haul many many truckloads of chipped wood products out to a small valley and dump it.  Imagine how much wood gas that chipped stuff would produce, then multiply that by a whole province which burns billions of cunits of waste wood logging by products per year!
Stan

Doug

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Re: CH4
« Reply #6 on: January 23, 2006, 07:12:22 PM »
Ya I know it sounds good Stan but it doesn't work properly with precup diesels and most of the testing done by the Swedes sugest that the injector tip will carbon and over heat, the fuel pump my seize from lack of flow and heat, The compression ratio will have to be dropped, injection timing advanced and these mods will make a hand cranked engine a real bear to start
The we get into the tar problems gumming up vavles and rings and high engine wear. And last but not least the exaust from a producer gas engine, even a diesel will have a high c0 content....

I've talked up some points on this with Doug Williams of Fluidyne and Greg Manning. These guys play their cards close to their chest because its not easy to make good engine grade gas. And this isn't like a car where a good bumpy road will keep your fuel bunker from bridging you need to baby sit a system like this. Now all that said I believe a GM 90 might be the best choice for a producer gas engine but never would I say this could be a trun key at breakfast and remeber to stoke it up again at night.

Doug

kpgv

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Re: CH4
« Reply #7 on: January 24, 2006, 03:14:01 AM »
Sounds like a match made in heaven for a "Kangaroo Jumper" "listeroid" on a longer frame and a leash :o ::) ;D

Kevin

SHIPCHIEF

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Re: CH4
« Reply #8 on: January 27, 2006, 03:53:59 AM »
Try:
http://belltown.typepad.com/belltown_bent/2005/08/
Timm Dowden runs a 1985 ranger on wood pellets.
I think the NATURAL GAS we should consider comes out of the south end of a north bound mammal. 8)
I once read about a South African pig farmer who couldn't afford to have the power lines brought to his farm, so he experimented with methane generation. He built sump digesters and hosed the pig poo into them. The gas ran his engine room. The gas pressure was set simply by the weight of the lid on the digester. One of the engines went 5 years before overhaul, putting to rest the 'sulfuric acid will eat the inside of your engine' arguement. He felt the high operating temps kept the acids from condensing in the engine, hence, no harm? Also the side benefit was reduced flies / pestilence at the farm.
Anyway, all organic matter can be used for methane feedstock, and the resultant sludge for fertilizer. Some may direct poo sludge to non food crops, your judgement here. :P
Methane generators are easier to operate than woodgas generators and alky stills, they require very little tending. The methane gas will be homogenous, so setting the mixture will be easier than woodgas and the power generated for a given engine will be higher.
Scott E
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's

SHIPCHIEF

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Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's

n2toh

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Re: CH4
« Reply #10 on: January 27, 2006, 04:44:10 PM »
What would you have to add to balance out the mix if you added large amounts of sawdust to the digester?
About 60 years is all it takes to make science fiction a reality.

SHIPCHIEF

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Re: CH4
« Reply #11 on: January 27, 2006, 05:06:20 PM »
Poo.
The sawdust would be a good carbon source for the mixture. It requires a ballance of water, poo and carbon bearing vegitation. The article I referenced does not really discuss the ratios, although the editor mentions it in the seventh paragraph. In this case hay from the barn floor was used, but more was needed? Enter here your sawdust.
I'm not an expert, but a web search provides alot of resources. A methane digester looks like a pretty big unit, but the process is easier to operate, and the gas is about twice as powerful as wood gas. The residual sludge is not a disposal hazard, it's fertilizer!
Try:
http://www.prep2003.com/methane.htm
The number of cows or chickens required for electric generation or kitchen stove seems rather large?
« Last Edit: January 27, 2006, 05:16:55 PM by SHIPCHIEF »
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's

admin

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Re: CH4
« Reply #12 on: January 27, 2006, 05:27:36 PM »
manure has a carbon to nitrogen balance of about 8:1 for good digestion you need about 15:1 hay is about 30:1 straw 80:1 and sawdust 500:1... just mix to balance

justsomeguy

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Re: CH4
« Reply #13 on: January 27, 2006, 09:15:28 PM »
For the sake of this discussion, I don't care if it comes from the earth, dead dinos, a digester, someone's butt, or factory that produces it out of ground up puppy dogs that were kidnapped from neighborhood kids............. :o

I just want to know if anyone's actually TRIED using natural gas as supplemental fuel for their Lister, since it can be used sucessfully with other high speed diesel engines, with little effort.  (Just add to intake air, and let the diesel fuel ignite it)  Or if anyone's considered trying it.

In a cogeneration setup, even with high natural gas prices, it's price per BTU is still substantailly less than that of diesel fuel, on the order of about 40-70% depending upon rates.

SHIPCHIEF

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Re: CH4
« Reply #14 on: January 27, 2006, 09:45:59 PM »
So...............
Ground up puppies stolen from kids????????? :-X
What you want to discuss is along the practical; "How Well Will a Lister Tolerate" natural gas.???
I think that is a very good First Question.
Rather than talk about making these gasses, you want to know if your engine will run on it.
I guess the first simple experiment would be on a running engine. In my case a generator set.
1)  Warm up engine and run at aprox 50% load at rated RPM. Record speed, rack position, and amps.
2)  Wave end of gas hose over intake manifold (air cleaner off) while slowly opening gas flow control valve.
3)  Observe engine speed and governor rack for desired / undesired changes.
4)  Withdraw / stop gas flow, observe return to straight diesel state, Log Observations.
5)  Determine results, modify / develope hardware, retest
6)  Modify test parameters, (increase KW load) retest

Like that?
Ashwamegh 25/2 & ST12
Lister SR2 10Kw 'Long Edurance' genset on a 10 gallon sump/skid,
Onan 6.5NH in an old Jeager Compressor trailer and a few CCK's