Homescale Bio Gas/Syn Gas/Wood Gas - Who's doing it? What's your story?

Hello home-brew gas enthusiasts!!

The intention of this thread is to gather first hand accounts of anyone who is or has made and used home made gas on a home scale. Are you using gas somehow? Tell us! Whether its a digester feeding a stove top or a woodgas driven truck or genset.. if it is or was in use I'd like to hear all about it...pictures are also nice!

Perhaps this thread already exists somewhere in the bowels of this forum, if not let this be it! If so, tell me to shut up and I'll dig harder to find it!

I'm interested in all of it:

How are you producing producing : digester or a gasifier or by some other means i'm not aware. If so, what kind?

If you are operating on demand (if gasifying) or storing. how?

What sorts of feedstock are you using?

What are your yields?

How are you using the gas?

Pros and Cons of your systems? What are the day to day challenges? If you were to do it again, what would you do differently?

I've spent a lot of time reading excellent posts by Marcos Buenijo, Bill Bianchi, Abe Connally and others on this forum with great interest. Following the links, checking out videos and reading the papers.

To reiterate what I'm interested in here is getting first hand accounts of Home scale gas producing and burning systems of all types and the realities of constructing, maintaining and using such systems.

Thank you!

j

Sorry only do it on a commercial scale.

Well since I haven't received any other posts yet maybe I've created too narrow a thread subject.

r john: What exactly are you up to? What do you mean by commercial scale ...or what scale of commercial do you mean? Do you operate a service related to the technology involved? Do you manufacture Methane Digesters or Biomass Gasifiers for sale? Are you involved with a larger group researching commercial applications? Please elaborate!

I'm extremely interested in examples of COMPLETE SYSTEMS that ARE or HAVE BEEN in use, ideally beyond the experimentation stage.

I think a thread full of actual applications of these technologies would be a really good read, if you ARE making money off of it or NOT!!

Let's think of this as a collection of successful, or even semi successful renewable (bio/syn) gas related project descriptions.

Any Takers?

Thanks!
j

Jay

I am into commercial woodfuel production drying split logs in solar kilns for the domestic market and woodchip for power generation. The woodchip is converted into torrefied wood using hot thermal oil in a sealed kiln which produces woodgas which is fed into a gas fired (Jenbacher) generator the waste heat from the exhaust heating the thermal oil the electric generated being fed into the national grid.

r john wrote:Jay

I am into commercial woodfuel production drying split logs in solar kilns for the domestic market and woodchip for power generation. The woodchip is converted into torrefied wood using hot thermal oil in a sealed kiln which produces woodgas which is fed into a gas fired (Jenbacher) generator the waste heat from the exhaust heating the thermal oil the electric generated being fed into the national grid.

John, please clarify the configuration. Your second statement suggests that you are feeding pyrolysis gas directly into the Jenbacher, but this doesn't seem right. Rather, are you fueling a gasifier with the torrefied wood chips, using the producer gas from the gasifier to run the Jenbacher, harvesting the waste heat from the engine with thermal oil, then using the thermal oil to torrify wood chips, then sending the pyrolysis gas from the wood chips into the gasifier for processing?

Marcos Buenijo wrote:

r john wrote:Jay

I am into commercial woodfuel production drying split logs in solar kilns for the domestic market and woodchip for power generation. The woodchip is converted into torrefied wood using hot thermal oil in a sealed kiln which produces woodgas which is fed into a gas fired (Jenbacher) generator the waste heat from the exhaust heating the thermal oil the electric generated being fed into the national grid.

John, please clarify the configuration. Your second statement suggests that you are feeding pyrolysis gas directly into the Jenbacher, but this doesn't seem right. Rather, are you fueling a gasifier with the torrefied wood chips, using the producer gas from the gasifier to run the Jenbacher, harvesting the waste heat from the engine with thermal oil, then using the thermal oil to torrify wood chips, then sending the pyrolysis gas from the wood chips into the gasifier for processing?

Marcos

The torrefication process is carried out in a retort which is heated by hot thermal oil. The gas given off whilst heating the woodchip to turn it into torrefied wood is fed into the jenbacher to produce electric the exhaust then heats the thermal oil. Nothing to do with FEMA type gasifiers

r john wrote:The torrefication process is carried out in a retort which is heated by hot thermal oil. The gas given off whilst heating the woodchip to turn it into torrefied wood is fed into the jenbacher to produce electric the exhaust then heats the thermal oil. Nothing to do with FEMA type gasifiers

I'm interested to understand the process. Heating wood in a retort with thermal oil will cause the wood to pyrolyse and release a gas very heavy in tar vapors. This is why I presumed there to be an additional gas processing step. I've never heard of a reliable engine system fueled by pyrolysis gas, so naturally I am excited about the prospect.

- What components lie between the retort and engine?

Marcos Buenijo wrote:

r john wrote:The torrefication process is carried out in a retort which is heated by hot thermal oil. The gas given off whilst heating the woodchip to turn it into torrefied wood is fed into the jenbacher to produce electric the exhaust then heats the thermal oil. Nothing to do with FEMA type gasifiers

I'm interested to understand the process. Heating wood in a retort with thermal oil will cause the wood to pyrolyse and release a gas very heavy in tar vapors. This is why I presumed there to be an additional gas processing step. I've never heard of a reliable engine system fueled by pyrolysis gas, so naturally I am excited about the prospect.

- What components lie between the retort and engine?

Marcos

I believe its a fluidized bed steam reactor from what I understand it contains a methane membrane. Its just standard kit on a Jenbacher woodgas engine. I dont think the slow pyrolysis produces the same tar problems that you get in a conventional low temperature gasifier. The majority of the gas produced in torrification is steam reducing the moisture content from 45% to 3 %.

r john wrote:I believe its a fluidized bed steam reactor from what I understand it contains a methane membrane. Its just standard kit on a Jenbacher woodgas engine. I dont think the slow pyrolysis produces the same tar problems that you get in a conventional low temperature gasifier. The majority of the gas produced in torrification is steam reducing the moisture content from 45% to 3 %.

Thanks for the replies. If this is a commercially available gasifier, then let me know of a web site that might be available where the system is described. There must be some sophisticated gas processing components in the system. I'm curious to check it out.

Marcos Buenijo wrote:

r john wrote:I believe its a fluidized bed steam reactor from what I understand it contains a methane membrane. Its just standard kit on a Jenbacher woodgas engine. I dont think the slow pyrolysis produces the same tar problems that you get in a conventional low temperature gasifier. The majority of the gas produced in torrification is steam reducing the moisture content from 45% to 3 %.

Thanks for the replies. If this is a commercially available gasifier, then let me know of a web site that might be available where the system is described. There must be some sophisticated gas processing components in the system. I'm curious to check it out.

Just type in Jenbacher woodgas filter. The engines are not small but they do know what there doing if your seriously into gasification.

Now things are starting to get interesting - here's a link to a brochure on the product

The product being a General Electric Jenbacher Gas Engine/Generator system. Commercial scale (indeed) gas engines designed to power generators and be fueled by a variety of types of gas.

I am starting a small scale biogas digester. Horse manure as the feed stock, inner tube storage. Will post pictures when later along in project.

A Jim Mason has devoted what appears to be 10+ years studying and reseaching wood gas. I would say any one interested in wood gas look at his work. It was all open source ('til last version). The website is www.gekallpower.com.

r john wrote:Just type in Jenbacher woodgas filter. The engines are not small but they do know what there doing if your seriously into gasification.

I have no interest in systems beyond the residential/individual scale.

Jay Peters wrote:Hello home-brew gas enthusiasts!!

The intention of this thread is to gather first hand accounts of anyone who is or has made and used home made gas on a home scale. Are you using gas somehow? Tell us! Whether its a digester feeding a stove top or a woodgas driven truck or genset.. if it is or was in use I'd like to hear all about it...pictures are also nice!

Perhaps this thread already exists somewhere in the bowels of this forum, if not let this be it! If so, tell me to shut up and I'll dig harder to find it!

I'm interested in all of it:

How are you producing producing : digester or a gasifier or by some other means i'm not aware. If so, what kind?

If you are operating on demand (if gasifying) or storing. how?

What sorts of feedstock are you using?

What are your yields?

How are you using the gas?

Pros and Cons of your systems? What are the day to day challenges? If you were to do it again, what would you do differently?

I've spent a lot of time reading excellent posts by Marcos Buenijo, Bill Bianchi, Abe Connally and others on this forum with great interest. Following the links, checking out videos and reading the papers.

To reiterate what I'm interested in here is getting first hand accounts of Home scale gas producing and burning systems of all types and the realities of constructing, maintaining and using such systems.

Thank you!

j

A few years ago I developed a gasifier forge. It operates on demand, I feed it with Virginia pine (useless otherwise) - it loves a good sappy knot. Some chunks are on the sides, the 1" pieces for operation, smaller stuff to start up. 3-4" length works good since the throat/burner is a scrounged piece of 3" stainless exhaust tubing. No idea of 'yield' but I was heating spikes to a bright orange. The fuel scoop is made of one.

ETA: Probably should mention this is an updraft gasifier (if it isn't obvious). Tar isn't a problem here!

Shelled corn works great too, as well as acorns. Best to mix them with the main fuel though, the corn particularly - it forms chunks of 'coke' that can choke it temporarily.

Very Cool, Bob and Nice pics too! Any more detail you can hook us up with on the design? On demand definitely seems like a wise choice in terms of wood gas. It seems that storage by any means other than the original biomass feedstock is pretty problematic. All in all this is a very cool solution to propane and natural gas forges!

Ed - I've poured over the All Power Labs GEK website, brochures, videos, and CAD files extensively. Very interesting innovation being done there.

I personally would like to get a small wood gasifier and generator set-up going in the future to charge batteries when the sun isn't shining or to run when more energy intense demands require. I'm also interested in generating enough methane to run a gas cook stove using jean pain style digester. I've found lots of info to research but not much of it includes personal experience with these types of small systems. It seems clear to me that the wood gas generator is certainly possible and the tech is pretty clear...what I haven't found is personal experiences with such a system and the realities of putting one together. The jean pain digester is however more nebulus as far as I can tell as there seems to be some disagreement on actual yield and process.

Any more takers?

j

Jay Peters wrote:Very Cool, Bob and Nice pics too! Any more detail you can hook us up with on the design? On demand definitely seems like a wise choice in terms of wood gas. It seems that storage by any means other than the original biomass feedstock is pretty problematic. All in all this is a very cool solution to propane and natural gas forges!

Ed - I've poured over the All Power Labs GEK website, brochures, videos, and CAD files extensively. Very interesting innovation being done there.

I personally would like to get a small wood gasifier and generator set-up going in the future to charge batteries when the sun isn't shining or to run when more energy intense demands require. I'm also interested in generating enough methane to run a gas cook stove using jean pain style digester. I've found lots of info to research but not much of it includes personal experience with these types of small systems. It seems clear to me that the wood gas generator is certainly possible and the tech is pretty clear...what I haven't found is personal experiences with such a system and the realities of putting one together. The jean pain digester is however more nebulus as far as I can tell as there seems to be some disagreement on actual yield and process.

Any more takers?

j

This has been through some changes. I started out by building an updraft gasifier in a piece of 6" stove pipe with an elbow and cap at the bottom for easy cleanout. At the top I used a cap with a 2' piece of 3" stainless exhaust pipe set into it, hanging into the stovepipe with a row of 3/8 holes below the cap for secondary air. Near the bottom of the pipe I made a horizontal divider from a piece of sheet metal with a hole in it for primary air to the bottom, and a cone of sheet metal for the valve - worked with a piece of coat hanger. I attached a stainless drain grate at the bottom of the 3" tube. The air inlet was in the side of the 6" tube so the air would be preheated before going to the lower section or secondary air holes. I foolishly installed it in a plywood base without enough clearance, so that didn't last long - even with some mud 'insulation'. I did build a mud/straw dome and was able to heat a few pieces of metal enough to go onwards. The metal cart presented itself at the time and seemed like a good solution so the stovepipe got mounted through a hole cut in the upper deck, centered by wires. The grate was the first thing to go so I stuck a piece of thin firebrick in the bottom for stuff to burn on, didn't seem to make any difference. Still building mud/straw domes, somebody said it looked like an anthill. My firewood sometimes having ants in it, I dubbed it "Ant Hell". I had also insulated around the outside of the 6" pipe with mud/perlite when I installed it in the cart.

Eventually the divider between the inlet/secondary air section and the bottom/primary air sections burned out. So I rebuilt it in the configuration shown in the pics. I wanted to make it somewhat modular but that didn't work out so much. I wanted the air valve outside if possible to avoid the same problem, and keep it accessable. I started by laying a short piece of 6" pipe and cap on the base of the cart for a cleanout. A couple pieces of thin firebrick form a hearth with a mud/straw ring around it 6" high to equal the piece of pipe. There is a primary air tube set into the ring too. A brake rotor sits down in this ring to form a grate to catch larger chunks and the crimped end of the upper piece of 6" pipe fits into it. This time I used a 4" inner pipe and wound up packing mud between that and the 6" pipe, up to the secondary air inlet. The top of the 4" pipe is about an inch lower than the 6" pipe, both have caps which hold a short piece of the 3" stainless exhaust pipe with the 3/8 holes in between. Secondary air enters the outer tube in the same place but doesn't get much preheating now. (I need a better solution in this area, the 4" tube has burned/rusted away higher than I can pack mud and allow air flow.) The outside was again encased with mud/perlite. On the top of the cart this time I built a platform even with the outlet and made the oven top with a form. The blower is an old microwave blower in a box with a damper on the inlet (usually a small opening, ~ 1/8" of a 2 1/2" hole). For the second version I added on a diverter valve - the round knob on the box to the right controls a vane that limits flow to the primary (or secondary if you wanted). There is a piece of iron on it because the hot melt glue wasn't working as anything but a gasket. Hadn't melted, just hadn't stuck well. Handy for checking inside anyway.

Direct heat applications seem like the best way to use gasification, skip the cooling, cleaning etc. Need low cost Stirling technology... I wonder if an alpha Stirling could be done with diaphragms.

Ok, I finally got around to putting up a picture of my/our biogas project. We haven't been working on it very much, but hope to get it running this spring/summer.



We still need to do the plumbing, fix a leak or two, and setup the gas collection.

Brett,

I've built several digesters, and wrote The Complete Biogas Handbook (www.completebiogas.com). Obviously then I have some thoughts about various digesters and substrates.

Horse manure will not generate as much biogas per dry pound as cow manure, and cow manure will not generate as much biogas per dry pound as pig manure. And no manure will generate nearly as much biogas as food waste (2x to 3x as much per dry pound). Further, building what I would call a practical digester from a 55-gal drum is either difficult or impossible, because in order to have what I would call " practical biogas" you will need to be generating enough gas to fuel some need: light, heat, cooking, electricity. Each use has its own hourly requirement. For light, it's about 100 liters per hour (3.5 cu ft); for heat it depends on ambient temp, size of place to heat, insulation and how hot one wants it to be (all pertinent details fully explained the book); for cooking figure about a cubic meter a day (35 cu ft); and for an engine or generator, it's pretty high at 425 liters per hour per HP (15 cu ft).

A digester kept warm and fed the right stuff will generate about its own volume in biogas per day, and a 55-gal drum is about 7 cu ft (200 l). That means that a warm 55-gal digester will not provide enough biogas to cook with, although it can offer some light if you have the right kind of lantern. (Like a Coleman lantern, but modded for biogas. These lamps are hard to keep working because the mantles are so brittle...)

The IBCs (Intermediate Bulk Containers) are 1 cubic meter (35 cubic feet), and so if you have the right slurry and keep it warm, a digester made from one of these will generate enough biogas for daily cooking, but it will be hard to make one work well for a long time as a continuous fed device. Most of the IBC digesters that I have seen work at very low solids (i.e. those that use toilet waste), and as such they will not generate their own volume daily.

More? I suggest visiting the complete biogas site and reading all the pages about building your own digester. Then ask any other questions you have. If I have time, I will answer. Meanwhile also in late April, I will be teaching a workshop that will give you all the info you need to pursue "practical biogas". Details at www.completebiogas.com/workshops.html

Hello David,

Thanks for the tips on biogas and digestors. I totally agree with you on the scale of a 55 gallon digestor. I believe most people are completely disconnected from the mathematics and the practicality of how much/little methane a digestor produces. This unit will be a demonstration unit for the farmer I am working with. We plan to use the gas for small home-scale herbal distillation via a small Bunsen burner. I was also asked when could be hook up a electric generator to the biogas digestor. I replied it would run for about 2 seconds before all the gas would be used up.

As for the fuel source all we have is horse manure. No pigs, cattle or food waste.

I'll keep your workshop in mind when I run into problems.