[Digestion] Solar Heated Batch Bladder Digester for Poultry
paul.harris at adelaide.edu.au
Sun May 22 19:09:00 PDT 2011
Welcome to the list!
I suggest you start your small unit and use that to see/learn what goes on
and how the system works. You will need sludge from an existing digester
(the local sewage works?) or fresh cow manure as a starting inoculum, but
once you have an operating digester the best inoculum is your own sludge.
There is a trade off, as the more inoculum you add the faster the start-up
will be BUT you will get less fresh manure in a given size digester (or you
need a larger digester for the same amount of feed). The minimum inoculum
seems to be about 10% but you can go to 50% or even more (which might be a
good idea for your first trials).
Have you seen the U-Tube video by Shelby Tyne, who is digesting chicken
manure in batch units, at http://www.youtube.com/watch?v=JCJyyA8LlnY?
Mr. Paul Harris, Room 202 Charles Hawker Building, Faculty of Sciences, The
University of Adelaide, Waite Campus, PMB 1, Glen Osmond SA 5064 Ph : +61
8 8303 7880 Fax : +61 8 8303 4386
mailto:paul.harris at adelaide.edu.au
CRICOS Provider Number 00123M
This email message is intended only for the addressee(s) and contains
information that may be confidential and/or copyright. If you are not the
intended recipient please notify the sender by reply email and immediately
delete this email. Use, disclosure or reproduction of this email by anyone
other than the intended recipient(s) is strictly prohibited. No
representation is made that this email or any attachments are free of
viruses. Virus scanning is recommended and is the responsibility of the
From: digestion-bounces at lists.bioenergylists.org
[mailto:digestion-bounces at lists.bioenergylists.org] On Behalf Of Steven
Sent: Monday, 23 May 2011 12:13 AM
To: digestion at lists.bioenergylists.org
Subject: [Digestion] Solar Heated Batch Bladder Digester for Poultry
I am a brand new subscriber to this terrific list.
We are a non-profit community based group on the Eastern Shore Maryland
"Delmarva" peninsula of the U.S.
Our main focus is the poultry farm water pollution of our abundant
waterways in the region, with the affects of year long outdoor storage,
and over application, runoff of raw chicken manure to the farmlands.
As mentioned already in this list, just one of the challenges with
poultry is that it is harvested from the chicken barns only five times a
year, which complicates a plug flow digester schedule and management
Our plan is as follows:
1) Run digestion process as a batch process, loading one time and then
after completed, empty with a separation to utilize liquid phosphate,
and semi-solids nitrogen materials as a more suitable agricultural or
2) Use "bladder bag" containments ... 12 feet wide, 23.5 feet long, 3
feet high (6,250 gallons). When manure is harvested (called "crusting
out"), it is transported from barn to adjacent "nest" (groups) of
bladder bags, .... instead of piled in open field or under a shed roof
until spring. Before each crusting out of barns it is assumed that the
Batch will have completed and can be emptied and ready for the next
3) Each Bladder Bag is set into a shallow excavation with only 6 inches
of bag above ground surface. Each bag system is covered with low profile
"greenhouse" providing passive heat. And we have internal water lines
that are connected to solar water heat collectors and solar powered
pumps to provide internal heat to the bladder bag.
We have already built a mini prototype of this, and have tested it with
only water in the tanks, no slurry yet. Starting with well water at 15
C, the time it takes to raise the tank temperature to a 40C is quite
remarkable. The passive solar heat from the "greenhouse tent" maintains
a daytime heat on the exterior of 44C - 54C.
Our expectation after some refinements and more insulation, to maintain
tanks at thermophilic levels with solar alone, for most of the year in
We are very new to AD. We do have the ability to consult with our local
University agricultural science departments. But as it seems in many
places, both information on batch designs and poultry manure use is scarce.
So my questions to the group:
1) Batch digester info in general
2) Innoculums, what to use, how to get them started ... and suggested
minimum percentage of a batch load .
3) Ammonia toxicity as it pertains to poultry and batch digesters.
4) Any comments on our design.
Some of the limiting factors of our region:
1) We have a very low water table, so in ground constructions with
concrete are problematic.
2) Federal limitations for lands determined to fall under "wetlands"
regulations cover most of our peninsula
3) Small to medium sized poultry farm's financial resources and method
of operation are not compatible with existing commercial systems.
Thank you so much in advance for any feedback. We have photos and three
dimensional renderings o our progress. And will be willing to share that
information with anyone who would like to help our project out.
Planet Foundation Ltd.
Digestion mailing list
to Send a Message to the list, use the email address
Digestion at bioenergylists.org
to UNSUBSCRIBE or Change your List Settings use the web page
for more information about digestion, see
Beginner's Guide to Biogas
and the Biogas Wiki http://biogas.wikispaces.com/
More information about the Digestion