Agriculture Reference
In-Depth Information
materials, liquid effluent, digester effluent and
post-digester solids.
Fibreboard
and building
materials can be manufactured utilizing digested
solids in place of sawdust (Winandy and Caia,
2008).
Seed pots
are being manufactured from
manures (CowPots). Manures can be used to
generate
granular active carbon
, which can be
used for water treatment (Lima and Marshall,
2005). Extracted proteins and amino acids from
manures can be utilized as feed ingredients; also
black soldier fly
prepupae meal, which are raised
on manures, can be a valuable feed ingredient
(Bondari and Sheppard, 1981; Sheppard
et al
.,
1994; Meyers
et al
., 2008). Carbohydrate mate-
rial from manure can be utilized to make
biode-
gradable plastics
and other products (ABCNEWS.
com, 2001). While there are many potential
value-added products that can be generated
from manure, none of these are currently in
mainstream production.
on site without interfering with animal/farm
management. Both of these hurdles will need
to be overcome in the future in order for these
innovative technologies to become common on
the average livestock farm. One other issue of
concern, in some cases, is the issue of scale.
Some technologies are proven on a very small
scale and would need to be scaled up to make
them economical on larger livestock opera-
tions. On the other hand, for some technolo-
gies such as biogas production, there may need
to be a larger source of feedstocks for the
technology to be cost effective, which would
eliminate the possibility of utilizing these tech-
nologies on smaller farms or would require
a central production site that received manure
from surrounding farms.
Future Research Needs
While many technologies for deriving more
value from manure exist there needs to be
more research done to improve the efficiencies
of these technologies and make them more
cost effective for the average producer. Some
examples of areas needing further considera-
tion are listed below, although this list is not
exhaustive.
•
Barriers to Manure Treatment
Technology Adoption
Although there are a great number of com-
mercially available systems for manure treat-
ment and fractionation including solid-liquid
separation, generation of biogas, nutrient
extraction and value added products, these are
still not common practices on most livestock
farms. There are two main driving forces that
prevent wide scale adoption of many manure
treatment and fractionation technologies. The
biggest deterrent to the adoption of many
technologies is that they are not economically
viable. While the technologies may be availa-
ble, they do not produce enough value to make
them attractive to most producers. This is due
in part to cheap energy prices, relatively low
costs of fertilizers, and a lack of demand for the
different products derived from manure frac-
tionation. Another large barrier to technology
adoption is the on-farm management of some
of these technologies. Most producers are
focused on managing livestock production and
do not have the time or interest to operate and
maintain other equipment on site. For many of
these technologies to be successfully adopted
and operated, third-party collaborators will
have to be involved that will be willing to
install, operate and maintain the equipment
Improve the N retention in composting
practices.
•
Improve solid-liquid separation and make it
more cost effective.
•
Improve thermal conversion technologies
to make them cost effective.
•
Improve anaerobic digestion technologies
to make them more cost effective.
•
Improve upon nutrient extraction technol-
ogies to improve economics.
•
Take proven technologies and scale them
up to make them economical on farm.
•
Evaluate existing and new technologies for
their potential to generate environmental
credits (sale of C offset and nutrient credits).
•
Develop new technologies to capture and
concentrate nutrients.
In addition to research, success of many of
these technologies would be dependent on sup-
port from government agencies or local com-
munities in order to make them economically
viable.
