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livingontheland - Re: [Livingontheland] Biogas etc./ was Fertilizer use by crop in Brazil

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  • From: "TradingPostPaul" <tradingpost@riseup.net>
  • To: livingontheland@lists.ibiblio.org
  • Subject: Re: [Livingontheland] Biogas etc./ was Fertilizer use by crop in Brazil
  • Date: Fri, 28 Apr 2006 18:24:53 -0600


Well, I can't keep spending my own time on the biogas business, because it's
not about building soil or growing in it - which is what I intended the list
for. I haven't touched on the other obvious problems with it, and why more
people aren't taking it seriously as a home energy alternative. It has to be
used as it's produced, which is awfully inconvenient, or else pressurized for
temporary (at least) storage which requires energy to pressurize and costs
more money for pressure tanks. Sorry but New Alchemy still raises more
questions than they answer, so I don't have time for them. And poor John Fry
in Santa Barbara simply forgot to factor in the cost of his own labor (and
equipment - did he use a loader?) for feeding manure to the digester every
day for six years. He conveniently left out any figures on what he lost by
not using it as it was produced, or if he pressurized it for storage what it
cost for the added equipment and cost of pressurizing. And I can't help
wondering, what did he do with all that gas in the summer in Santa Barbara?
Make speeches about biogas?

paul, tradingpost@riseup.net
---------------
The care of the Earth is our most ancient and most worthy, and after all our
most pleasing responsibility. To cherish what remains of it and to foster its
renewal is our only hope.
- Wendell Berry
*********** REPLY SEPARATOR ***********

On 4/28/2006 at 5:56 PM Greg and April wrote:

>The carbon came from the wood chips.
>
>When I was saying chips, I wasn't talking about chunks, but, something
>more
>along 1/2-3/4 inch max. Shreds might have been a better term.
>
>You can look up the data that New Alchemy used ( they have 69 references,
>but I'll just give a few ):
>
>Compost:
>
>Poincelot R. 1972
>The Biochemistry and Methodogy of Composting.
>Connecticut Agriculture Experiment Station
>Bulletin 727 March 1972
>New Haven Conn
>
>Digested Manure:
>
>Hog:
>Taiganides, Eliseos P. 1963
>Characteristics and Treatment of Wastes from a Confinement Hog Production
>Unit
>PhD dissertation, Iowa State Univ.
>Science and Technology, Agriculture Engineering.
>Available from University Microfilm Inc.
>An Arbor Mich #63-5200 ( 177 pg )
>
>Cow:
>Hart, Samuel 1960
>Sludge Digestion Tests of Livestock Manures
>Dept. Agr. Engr. Univ. of Calif. Davis
>Offprint manuscript.
>
>The amount of methane generated is based on several factors including
>waste
>material used ( even manure from different animal types can vary the
>amount ), the temperature, the time in the unit, and even the amount of
>dissolved solids in the slurry ( since it's the dissolved solids that
>actually do the job ).
>
>
>Costs to build units vary, with such things as the materials used.
>Smaller units can be built from scrap 55 gal barrels that can be had for
>free, if you know where to look. They can be made from concrete if that
>is your style and your budget I built one out of a 3 gal pickle jar,
>when
>in high school, just to see if it would work, using dog manure ( from when
>the neighbors dog would go in our yard ) and it did.
>
>
>Some rough figures.
>(from Methane Digesters for Fuel Gas and Fertilizer )
>
>Cattle manure
>100% 1.4 cu Ft ( per lb of Volatile Solids) 65% CH4
>
>Chicken manure
>100% 5 cu Ft 59%
>
>Chicken manure /
>paper pulp
>31%/69% 7.8 cu Ft 60%
>
>Chicken manure /
>grass clippings
>50%/50% 5.9 cu Ft 68%
>
>( from Hand Book on Bio Gas and It's Applications )
>4 cattle ( as we can see above they are not the best source ) and a 5 cu m
>( 177 cu Ft ) gas unit, and retain for 50 days you will be producing 1.55
>cu
>m of gas @ 20*C ( 54.7 cu Ft @ 68* F ) every day.
>
>How long it takes to repay initial investment is highly dependant on the
>amount invested, and what the gas is worth to the person using it.
>
>The digester built by John Fry ( that I mentioned a month or so ago ) on
>his
>hog farm ( average 1000 hogs ), cost him about $10,000 to build, and
>produced 8000 cu ft of bio gas a day ( 4,680 BTU's a day ). His figures
>showed that this was worth $7.57 a day in Santa Barbara Cal. in 1973, or
>$16,578 in 6 years just for the gas alone, and not for any fertilizer
>value.
>So his return of investment, was less than 6 years.
>
>Another way to look at it:
>
>Average cost per Hog to build: $10
>Average amount of Bio gas per hog: 8 cu ft a day
>Average number of BTU's per hog: 4.68 each day
>Amount of liquid fertalizer: Approximately 500 gal every 3-4 days ( 125 -
>170 gal / day ) - for an average of 1000 hogs.
>
>As mentioned above, even as few as 4 cattle can produce 54 cu ft of bio
>gas
>each day, and used effectively, that is enough to provide supplemental CO2
>and keep a green house warm on chilly nights.
>
>It all comes down to how people apply the resources that are available.
>Let manure do nothing over fall and winter, or use it to heat a greenhouse
>in winter that might otherwise go unheated. What is the value of
>growing
>cool crops in the middle of winter in the green house? That is
>something
>that people will have to figure out and decide for themselves. Is there
>value in fresh out of season crops? If so how much?
>
>Every week I meet people that say " I didn't know that " or " I thought
>you
>couldn't ... "
>
>Personaly, I think the problem with digesters is, people don't try because
>they thought they couldn't .... Until more people do try, we will never
>know for sure.
>
>Many people still think that cars can only run on something that comes out
>of the fuel pump at the gas station, and don't think that they can make it
>them selves, because that is what they are used to thinking ( not to
>mention
>brainwashing ).






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