[mosa]

please note that we are looking for some sort of economical method in order to dispose cattle dung from our cattle farm which produce 200 mts daily .
so if there is any one interrested and have some constructed ideas we are willing to discuss same.

thanks
mosa

[Ludi]

Here are some links about methane digesters, an easy and inexpensive way to convert dung into fuel:

http://www.eco-farm.org/sa/sa_dairy_syn ... ester.html

http://www.suscon.org/dairies/methanedigesters.asp

http://www.ias.unu.edu/proceedings/icib ... coAguilar/

[backstop]

Mosa -

Welcome to the board.

While I'd agree with Ludi that producing Methane (CH4) from cattle dung is a very sensible option, there are various points to consider.

1/. The scale of capital plant (& investment).
Am I right in reading 200 mts /day dung output as being 200 cubic metres ?
Given a 35-day fermentation process thruput this would require over 7,000 cubic metres of fermentation chamber capacity
(to accomodate the requisite additional inputs), which is a pretty sizeable bit of construction.

2/. Using the methane product.
This might perhaps find local users, but I doubt any conventional gas supplier would let you mix your raw gas (CH4 + CO2) with their refined product -
so conversion via fuel cells to relatively easily saleable electricity may be the best option.

3/. Disposal of the slurry (your actual question).
Anaerobic fermentation greatly raises the value of the slurry as fertilizer,
so you might consider either trucking it (wet) to farms hit by rising fertilizer prices (high energy & $ expense)
or using a part of the methane energy to centrifuge, pelletize & bag the solids as a lightweight and easily marketted fertilizer.
The latter option would yield a substantial liquid volume per day which might, with relatively minor outlay, be released to a large reedbed purification system.
The annual yield of biomass from this could itself provide a significant additional energy resource.

My guess is that you need to find a really good specialist in the field who works in your area
to help you identify & design the most appropriate system for your circumstances.

Hoping this may be some help,

regards,

Backstop

[Ludi]

You're welcome to your opinions, pstarr. Any time you want to come up with solutions of your own, be my guest.

Few are using it yet probably because farmers change practices very slowly, especially if something is seen as "greenie" or "environmentalist."

[Ludi]

By the way, I never make any claims that anything will contribute to a "post peak energy deficit," or what you call cornucopian solutions. This is meant as a home-or-small community scale solution.

I have to say, I'm just so tired of this shit from folks, so tired of it.

.

[Edited for unproductive, if understandable, language, by Backstop, to avoid the thread getting wasted in the HoF- ]

[Ludi]

Methane digesters can be made on any scale.

Really. You can make one to use your own poop.

This is not a "solution in isolation" this is a solution in a whole system of material use which makes a circle from the backside (poop) to the kitchen (cook with methane) through the garden (grow plants to feed animals), etc.


I'm so tired of this arguing over trifles. Stop this and DO SOMETHING!

[backstop]

I'd like to hear more from Mosa of the actual details of how the farm is set up, as we're rather under-informed to make much useful comment thus far.

For instance, the Carter years put over 60,000 brick-built methane digesters into villages in India,
but failed to test villagers' willingness to walk round their land each day collecting the dung and carting it to the village,
so by 1990 there were 60,000 digesters standing idle.

If, OTOH, the farm has the dung concentrated each day on concrete at the milking sheds, it's another matter.

If, as I suspect, the farm doesn't have enough land to spread the dung and are buying in feed for the stock,
then, given the clearly predictable oil-price-based rise in feed prices,
there may actually be a better case for re-orienting the farm to traditional mixed farming to avoid potentially ruinous dependence on trucked-in feed,
rather than for heavy capital investment in optimizing the return from the present daily dung output.

So Mosa, could you clarify your position on these matters ?

regards,

Backstop

[Ludi]

Rotational grazing including pastured poultry could make good use of dung on grassland.

Or is that a "solution in isolation"?