Posted by Curbie on December 12, 2009, 11:31 pm
I've been toying with the notion of anaerobic methane production of
bio-mass (algae from a raceway pond). I need compost anyway for my
garden, so a algae pond has appeal on it's own, but I read a couple of
books one by Jean Pain and the other by John Fry, so by anaerobic
composting I'll still get same amount of compost but also a surprising
amount of methane as a bonus.
Since methane is chemically 4/5 hydrogen it has sort of the same
storage problem that hydrogen has, which is to say that neither gas is
very portable, but is interesting for both cooking and stationary
I've been playing with sketch-up in an effort to visualize what would
be involved with constructing such a notion, came up with this:
What you're looking at is a raceway paddle-wheel that provides water
movement, the intake gate funnels a portion of water/algae and a
filter by the exit gate concentrates algae in the channel on the left.
Then the gates are both closed and the concentrated algae/water is
pumped out of the channel into the digester where the water is again
filtered out by gravity and return to the channel. When the water
pressure equalizes between the channel and the raceway, the gate are
Any help on the function of this notion would be appreciated.
Posted by Jim Wilkins on December 13, 2009, 12:17 am
I would try batch production first to learn and improve the process.
Posted by Curbie on December 13, 2009, 2:45 am
I will, for me anyway, the base question is an algae pond practical to
produce compost for a large garden, even if I was just pumping into a
pile on the ground and letting it compost aerobically, if it is, the
methane produced is gravy.
In his book, Jean Pain used the formula of 5kg of vegetable bio-mass
produces 1m^3 of GAS, John Fry give the rough composition of the GAS
as methane 63%, CO2 33%, and the rest N2, H2, CO, O2, and H2S. I
don't know if I believe these numbers but if there even half correct,
the ability to produce large volumes of bio-mass would have multiple
This notion brings me to growing indigenous algae in a raceway pond.
I'm also thinking about digesters, gas scrubbers, compression and
storage, but all that is dependant on my base question.
The great thing about experimenting on bio-mass from indigenous algae
is that is practically free, not to mention I would really groove on a
couple tons of compost.
Posted by Michael B on December 13, 2009, 3:15 am
Raceway, paddlewheel, water movement. Sounds more aerobic
Posted by Curbie on December 13, 2009, 4:14 am
"I've been toying with the notion of anaerobic methane production of
bio-mass (algae from a raceway pond)."
The notion is algae grown in, and collected from a raceway pond, the
bio-mass (algae) is then composted in an anaerobic digester to produce
compost and methane.
Which anaerobic Witch is Which.