The Rural Voice, 2004-10, Page 43Advice
Additives help reduce odour, gas in composted manure
An innovative project at the Olds
(Alberta) College School of
Innovation will demonstrate that
adding two aluminum -based minerals
to composting beef manure will help
reduce odour and greenhouse gas
emissions, while retaining valuable
nutrients.
The two aluminum silicate
products are volcanic minerals called
zeolite and perlite. The naturally
occurring minerals are commonly
used in a number of industrial
applications. Zeolites, which can
filter, remove odour and absorb gas,
are often used in water softeners.
Perlite, a glassy volcanic rock, is
familiar to many people in the
"popped" form as a compound found
in plant potting mix.
"Preliminary results of earlier
research suggest that when these
minerals are ingested by cattle
through feed, they may reduce
methane production in the rumen,"
explains Dr. Abimbola Abiola,
project leader. "With this project, we
intend to show we can achieve a
similar reduction in greenhouse gases
by adding the compounds to feedlot
manure in the composting process."
The process will produce a high
quality compost, to be used as a bio -
based soil amendment. Along with
nutrient value, compost also helps
improve other soil quality
characteristics.
The demonstration project is
being funded in part by the
Greenhouse Gas Mitigation Program
for Canadian Agriculture (GHGMP).
The federal program is designed to
promote awareness of agricultural
practices that reduce atmospheric
levels of greenhouse gas or increase
carbon storage in soils. The Canadian
Cattlemen's Association (CCA)
administers the delivery of the beef
sector component of the program. A
report on this project is posted on the
CCA Web site at www.cattle.ca.
The project site is located at the
Olds College Composting
Technology Centre. In the first year
of the project, seven windrows were
assembled using manure from the
Olds College feedlot, says Abiola.
Volcanic minerals added to compost may reduce odour and green house
gas production. Test in Alberta are exploring the possibilities.
One windrow, without any
treatments, will be used as the
control, while the other six windrows
include a combination of manure and
aluminum silicates. Three windrows
will contain zeolite and three will
contain perlite in various
percentages.
The windrows will be turned at
specific times to ensure effective
aerobic composting. Gas emissions
will also be monitored to measure
methane, carbon dioxide and nitrous
oxide production. Gas measurements
will be related to the amounts of
zeolite and perlite added to the
compost.
"Our research is not only to show
how the silicates work in reducing
greenhouse gas emissions, but also to
determine the economics." says
Abiola. "We need to determine the
economic ratio of aluminum silicates
for the amount of manure being
composted and the benefits being
achieved."
Once the active composting
process is complete, the compost will
be left to cure. In the second year of
the project, the treated and untreated
composts will be applied to field
crops and pastures and compared to
commercial fertilizer.
Abiola says adding aluminum
silicates to the composting manure is
an effective way to manage manure.
Essential nutrients are retained. while
greenhouse gases naturally produced
during the composting process are
minimized. The Olds College
demonstration is intended to show
the environmental and economic
benefits of composting. He says
feedlot operators will he able to
expand their manure management
options and use this valuable bio -
based soil amendment on their land.
There may also be opportunities to
sell,the composted manure as a
commercial product.
"Composting beef manure could
provide a cost effective,
environmentally friendly solution to
many manure management issues
such as volume. odour and timing of
application," says Abiola.
The success of the Alberta project
will have national implications. If
shown to be both practical and
economical, livestock producers
across Canada would be able to
implement the system.
The GHGMP supports a broad
range of projects across Canada. For
more information on this project and
other beef sector activities, visit the
CCA's Web site: www.cattle.ca.0
OCTOBER 2004 39