Now that's interesting.
Previously, the equation train went from urea [(NH2)2CO] to ammonium
carbonate [(NH4)2 CO3] to ammonium [2 NH4] and carbon dioxide [CO2 gas)]
& then I stopped at ammonia [NH3 gas] and water [H2O].
But I guess (from what you said above) some of that atmospheric ammonia
is converted to nitrous oxide (probably by oxidation of the ammonia?):
2 NH3 + 2 O2 β N2O + 3 H2O
Is that urea reaction path above correct yet?
The stoichiometry looks right. I'd have to look up the reaction sequence to be
Nitrous oxide (N2O) is a strong greenhouse gas with global warming
potential (GWP) which is much greater, by 310 times, than that of CO2.
I have to ask why ? As an academic exercise? Not much reason to save
it. Urine is pretty cheap and fairly renewable for most of us. In a
compost pile I would let it go do it's job unhindered. Unless you test/
analyze your homebrew, hot or cold, your only guessing as to its
nutrient content. So the urine is just feedstock and not a nutrient
at this stage.
As for using urine in your soil, you and others gave some good info as
to how best to use. I did read excerpts from one of the Finnish
team's three experiments wherein Surendra K. Pradhan, K. Holopainen
and Helvi Heinonen-Tanski of the University of Kuopio in Finland
collected human urine during the winter of 2007-2008 from several eco-
toilets in private homes. The urine was stored for about six months at
45 degrees F and tested for microbes and bacteria. The team mixed it
with wood ash collected from a household furnace, and found the
mixture was just as good as -- or better than -- conventional chemical
fertilizer. So I would assume urine was relatively shelf stable for
at least that amount of time/temp. Here is a lead on her email if you
want to ask first hand: firstname.lastname@example.org .
WA State's land grant site on Composting :
Another link that maybe helpful w/ your quest:
I do have to say that while the average person's urine maybe safe
there is increasing concern about Environmental Pharmaceutical
Persistent Pollutant (EPPP) which do show up in edible plant, albeit
in low doses. Always test or know your source well!
The paper purports to answer exactly what I'm asking!
"The purpose of this fact sheet is to briefly describe urea
transformations and to suggest how urea-N may be conserved
with proper management in the field."
It says up to 90% of the nitrogen in urea will turn to ammonia gas "if
not protected within a few hours of application".
Since urea -> ammonium bicarbonate (within 48 hours) -> ammonia gas, they
say the key to keeping the nitrogen is to "put the urea into the soil and
not merely on the soil" within those first 48 hours.
Ah. That's simple! They say you can do this three ways:
1. Water the soil directly after applying the urea
2. Plow the soil after fertilization
3. Inject the urea into the soil
How did you find this? I had googled for hours before posting my question
because I could not find the answer of how to keep the nitrogen IN the
In my compost pile, I can keep it wet and I can cover it with soil to
keep the nitrogen in the soil!
Your closest land grant university might have answers to
questions if you have any. List here: http://tinyurl.com/3r39ax
The University of Nebraska at Lincoln, for example, has NebGuides.
here: http://tinyurl.com/unvrl They deal primarily with
agriculture but there is some information on lawns and
On Mon, 16 Jan 2012 01:56:05 +0000, Chuck Banshee wrote:
I recently found this, an entire doctoral thesis, on the fate of
radioactive nitrogen in urine applied to soils over a period of time.
Title: Fate of urine nitrogen applied to peat and mineral soils from
grazed pastures, by Timothy John Clough, Lincoln University, 1994.
Or wash it away into aquifers, or public water ways. The amount of
ammonia needed to produce the same yield from a field will increase as
the organic material (OG) in the field's soil breaks down and
diminishes. Discing OG into the field disrupts the soil structure and
With urea, you needn't spare its application, as you have a lifetime
supply of it. Do spread it around though, as you can get salt (ionic
compounds that result from the neutralization reaction of an acid and a
base) build ups if it only supplied to one small area of soil.
The Bottom Line
β’ Ideal soils, from a fertility standpoint, are generally defined as
containing no more than 5% OM by weight or 10% by volume
β’ Before you add organic amendments to your garden, have your soil
tested to determine its OM content and nutrient levels
β’ Be conservative with organic amendments; add only what is necessary to
correct deficiencies and maintain OM at ideal levels
β’ Do not incorporate organic amendments into landscapes destined for
permanent installations; top dress with mulch instead
β’ Abnormally high levels of nutrients can have negative effects on plant
and soil health
β’ Any nutrients not immediately utilized by microbes or plants
contribute to non-point source pollution
Here, for the record, is a picture of my ad hoc 'compost' bucket ...
where I put all kitchen food-related trash (eggshells, banana peels,
lettuce cores, chicken bones, fat cuttings, orange peels, stale bread,
Notice the patented NPK 12:1:2 fertilizing formula I've been using,
thanks to all your advice!
So far I've been emptying this about once a week into a large wheeled
green compost bucket (which is half full and getting unwieldy).
The bottle of urine you see there is about a day's output from yours
* That's about ~1.5 liter / day / person
* Which is about 7.5 grams of Nitrogen per day
* And about 6 pounds of Nitrogen, 1 pound Phosphorous, & 2 pounds of
Potassium per year
I wonder what a comparison cost would be for equivalent store bought NPK
12:1:2 fertilizer containing 6 pounds of nitrogen?
On Sat, 21 Jan 2012 22:34:54 -0600, The Daring Dufas wrote:
I agree the yuck factor is high.
But, I'm at least learning yuck that I never knew before ... for example,
on Saturdays I deliver double my normal urine output - and - the color
tends to fade to a lighter amber (as shown in this picture taken today of
the second bottle of the day):
And, the practical (yuck) experience doesn't stop there.
For example, I found that this width bottle is too small for a normal
person to fit and therefore there's the need for a wider bottle opening
(two inches would seem to be a good bottle opening size for a 2 liter
Use laundry detergent plastic jugs. Wide mouth, easy to
fit with no= fiddling around .....
I keep one under the bed to keep from stumping my toes at
night, and one in the truck so I don't have to stop and go
into a gas station after every beer.......
They are empltied into a raised bed garden, in those spaces
where I've already picked the produce.....
I have a plastic urinal I got during my last hospital visit where I had
to keep track of urine output. I keep track of output every now and then
especially after I peed out 50lbs of fluid in two weeks last fall. In a
month I was 60lbs lighter after getting the right medication. No more
fluid in my lungs went a long way toward making me feel better. ^_^
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