Posted by kanon11 on July 4, 2013, 8:17 am
Hi all, I'm planning to make a biogas digester to connect to my mobile home
's sewage out port. Hopefully this will make fertilizer, a bit of methane,
and possibly electricity, as I've read that anaerobic breakdown of organic
matter can run a microbial fuel cell. My main question at this point is how
the fertilizer is extracted? On all the plans I've see, the tank is buried
with an input and output pipe going down into it. Somehow, the effluent se
ems to flow up and out the output pipe, but I can't for the life of me figu
re out how that works. It seems to defy gravity. Can anyone enlighten me? B
uilding this will save me from trips to the dump station and use my poop fo
r good rather than being a hazardous waste.
Posted by Vaughn on July 4, 2013, 12:13 pm
On 7/4/2013 4:17 AM, firstname.lastname@example.org wrote:
What you are describing doesn't sound much different from a septic tank.
For a travel trailer with only my father living in it, I once made a
septic system from a single buried 55-gallon drum and about 20 feet of
drain line (sandy soil). The system worked fine for the couple years
that it was needed. (He ultimately found a new wife who owned a condo,
and so moved out of my yard.)
That was done in a different time when local officials were far more
casual about such things, so don't take the above as a suggestion. It's
likely illegal these days and possibly a very bad idea depending on your
soil type and groundwater situation.
As for digesting solids, you will be surprised how efficiently a septic
system reduces them. I have been living in this house for some 30
years, yet we have never pumped the septic tank!
You might hunt around for a more appropriate group that can give you
more input. Perhaps gardeners or even survivalists.
As for the fuel cell idea; for a thousand reasons, forget it.
Posted by kanon11 on July 4, 2013, 9:47 pm
Thanks for the feedback. Yes, it's similar to a septic tank, but it will pr
oduce methane and fertilizer (and electricity, though I'm curious about you
r reasons for a microbial fuel cell not working), without the ground water
contamination problem. It will also produce heat, and larger versions can o
utput 140 degree water.
As for the fuel cell, it seems prototypes are cheap and easy to build. Migh
t produce a volt or so at a few hundred mA. These are small tabletop models
, so a septic tank size will likely produce a lot more.
Anyway, my question still stands: how does the compost climb up and out the
Posted by mike on July 4, 2013, 10:39 pm
On 7/4/2013 2:47 PM, email@example.com wrote:
Please publish some links to the fuel cells that run on the gas you can
Posted by Kanon Kubose on July 5, 2013, 12:07 am
Not the gas. The microbes. Here's the little tabletop demonstration model you can buy: http://www.keegotech.com/ScienceKits/HowMudWattWorks . Here's someone building their own: http://www.instructables.com/id/DIY-Microbial-Fuel-Cell-easy/