my dad has 360 cows with a liquid manure system 950,000 gals storage
I think every time we spread this on the feilds that this could be sent through a digester to capture some gas and reduce the smell for the nabors !
We could be setting on a 950,000gal pit of monney I think we are as bad as it smells now its a littel hard to beleive
but I want to start with a small system so I can make mistakes in a small scale before investing $ in a large one that is not right!
I think people are making these digesters more complex then they need to and sinking alot of monney into a tank to prosess manure
so I was wondering if there was any plans on methane/biogas digesters I also would like to find plans for a biogas scrubber detailed pictures would even help I have no idea how a scrubber works all I know is it cleans the gas not even shure if I need one but I think I do? and what type digester is the best? I live in a cold climent I have heard of a plugflow but not in detail
once I have a small system mastered I could move on to a large scale and maybe if it goes well I could send you plans for a large scale system! of my own desine
if you can help me E-MAIL ME AT:
chuckcat4@yahoo.com
digester
Moderator:Bob
The USEPA AgSTAR program is probably one of the best sources of information available for large digesters suitable for a dairy farm of that size. They also have a free computer program that you can use to determine the feasibility of a biogas digester for your farm.
What did you have in mind for a 'small system'? Something like a 55 gal drum just for experimenting?
re. scrubbers, whether or not you need one depends mostly on what do you want to do with the gas. It's probably not worth the cost, unless you will be burning the gas in an engine and, because of operating conditions, you have a problem with excessive amounts of H2S.
[This message has been edited by Bob (edited 12-31-2002).]
What did you have in mind for a 'small system'? Something like a 55 gal drum just for experimenting?
re. scrubbers, whether or not you need one depends mostly on what do you want to do with the gas. It's probably not worth the cost, unless you will be burning the gas in an engine and, because of operating conditions, you have a problem with excessive amounts of H2S.
[This message has been edited by Bob (edited 12-31-2002).]
thank you for your fast responce
some forums take weeks thanks!
I fig why reinvent the wheel hear some one out there has done this many times I should be able to copy in small scale it and improve on it with my working model to profection
:answer to your questions any more feel free to ask them im new at this but very handy at building things im the guy that has to take it apart to see how it works then I can build it from scratch but I am a bad at spelling!
around 55gal or larger or smaller would be fine for experimenting with
the end goal if it goes well is to run a biogas engine so I will need to learn about scrubbers
feel free to tell me if you feel I am going in the wrong direction I am a newbie very green in this area!
also do you know how horse manure would work in a digester my freind has horses and is verry interested in if he can run a digester on road apples alone? and how much gas he can make per horse? he thinks this will give him a good reason to get more horses that his wife might except!
some forums take weeks thanks!
I fig why reinvent the wheel hear some one out there has done this many times I should be able to copy in small scale it and improve on it with my working model to profection
:answer to your questions any more feel free to ask them im new at this but very handy at building things im the guy that has to take it apart to see how it works then I can build it from scratch but I am a bad at spelling!
around 55gal or larger or smaller would be fine for experimenting with
the end goal if it goes well is to run a biogas engine so I will need to learn about scrubbers
feel free to tell me if you feel I am going in the wrong direction I am a newbie very green in this area!
also do you know how horse manure would work in a digester my freind has horses and is verry interested in if he can run a digester on road apples alone? and how much gas he can make per horse? he thinks this will give him a good reason to get more horses that his wife might except!
chuckcat4, if you are interested in a large dairy farm biodigester, you probably can't do better than with the info and resources available from Agstar. Have you reviewed it? To start from scratch, experimenting with 55 gal drum-size digester would be reinventing the wheel, in my opinion.
But if you want to experiment with some small-scale systems anyway, you should be able to answer most of your questions using my on-line calculator.
But if you want to experiment with some small-scale systems anyway, you should be able to answer most of your questions using my on-line calculator.
Hi Hereford,
"Scrubbers" is a big topic. There are a variety of different types, used to remove a variety of unwanted gases and/or odors. Not to mention a variety of sizes. When you say "big" biogas projects, what does that mean?
There are also a wide variety of factors which affect the production of CO2 and H2S, including temperature, pH, C/N ratio, retention time, etc. You may be able to control gas quality to acceptable levels with careful management alone, depending on how you intend to use the gas.
Having said that, you can remove CO2 by bubbling the gas through limewater, (or sodium hydroxide, or any other alkaline chemical for that matter). What happens is that the CO2 and water combine to form carbonic acid, and the alkaline chemicals remove the carbonic acid to form calcium bicarbonate. Then to regenerate the solution, expose to air.
One idea I've been working on is to combine a floating-cover gas collector & CO2 scrubber, i.e. using limewater instead of plain water in the gas collector, and adding a small compressor and recirculation line to recirculate the biogas collected under the cover back to bubble up through the limewater continuously.
I'll post a sketch here when I can get to it.
H2S can be removed by flowing it through ferric oxide (rust). You can take some iron filings, mix with moistened sawdust, then, after well rusted, pack into a pipe and pass the gas through the pipe. The H2S reacts with the ferric oxide to produce ferric sulfide.
There's a lot more to it than that though. When the ferric sulfide is exposed to air, it reverts to ferric oxide plus sulfur, producing a lot of heat in the process.
If it were me, I'd first try to control H2S with digester management before going to the trouble & expense of scrubbing. If it can be kept to < 0.1% by volume it shouldn't be a problem, even in an internal combustion engine.
Here are links to a couple of commercial scrubber manufacturers:
Apollo Environmental and SulfaTreat
"Scrubbers" is a big topic. There are a variety of different types, used to remove a variety of unwanted gases and/or odors. Not to mention a variety of sizes. When you say "big" biogas projects, what does that mean?
There are also a wide variety of factors which affect the production of CO2 and H2S, including temperature, pH, C/N ratio, retention time, etc. You may be able to control gas quality to acceptable levels with careful management alone, depending on how you intend to use the gas.
Having said that, you can remove CO2 by bubbling the gas through limewater, (or sodium hydroxide, or any other alkaline chemical for that matter). What happens is that the CO2 and water combine to form carbonic acid, and the alkaline chemicals remove the carbonic acid to form calcium bicarbonate. Then to regenerate the solution, expose to air.
One idea I've been working on is to combine a floating-cover gas collector & CO2 scrubber, i.e. using limewater instead of plain water in the gas collector, and adding a small compressor and recirculation line to recirculate the biogas collected under the cover back to bubble up through the limewater continuously.
I'll post a sketch here when I can get to it.
H2S can be removed by flowing it through ferric oxide (rust). You can take some iron filings, mix with moistened sawdust, then, after well rusted, pack into a pipe and pass the gas through the pipe. The H2S reacts with the ferric oxide to produce ferric sulfide.
There's a lot more to it than that though. When the ferric sulfide is exposed to air, it reverts to ferric oxide plus sulfur, producing a lot of heat in the process.
If it were me, I'd first try to control H2S with digester management before going to the trouble & expense of scrubbing. If it can be kept to < 0.1% by volume it shouldn't be a problem, even in an internal combustion engine.
Here are links to a couple of commercial scrubber manufacturers:
Apollo Environmental and SulfaTreat