Transcript Manure – A Multi-Purpose Resource: ”Things are Changing in

Re-Defining Confined Livestock Farming:
Making Carbon Work for Us
Bruce T. Bowman
Expert Committee on Manure Management
Canadian Agri-Food Research Council
Presented at:
CARC Annual Meeting
Ottawa, Ontario
April 21, 2005
Presentation Objective
To demonstrate the central role of manure processing &
farm bio-energy systems for revitalizing rural economies
- GHG’s
- Odours
Environmental - Pathogens
Remediation - Deadstock
A.D.
Manure
Processing
Farm
Economic
Benefits
Nutrient
Issues
- Conservation
- Recycling
- Nutrient
availability
Rural Society
Benefits
Farm Bio-Energy
Priority Issues
for Manure Management
Three priority issues to manage:
 Nutrients
 Odours
 Pathogens
............................. but also …….
 Water volumes
 Carbon = Energy  $$$
Conserving Nutrients:
Gaseous Nitrogen losses from Manure
In this section I will be developing linkages between nutrient
conservation/recycling and manure processing.
 Two major loss pathways:
 As volatile ammonia (NH3)
- Adjust pH to near 7.0 to minimize ammonia losses
- Rapid losses from freshly-exposed manure
 As nitrous oxide (N2O)
- Processed manure  less N2O emissions following
land application – 50% less C (energy) for microbes)
Trends in the Fertilizer Industry
-- Post WWII (1945) - Cheap & plentiful mineral fertilizers helped spur
intensification and specialization in production
agriculture after 1945.
 Cereal production (cash-cropping) is often separate from
livestock production, relying only on mineral fertilizers.
(Mixed farming systems tend to be more sustainable).
 Intensification has created some regional nutrient surpluses
(Quebec, N. Carolina, Chesapeake Bay area, Lower Fraser, BC).
 Consequence: Nutrients in livestock manures (originating
from imported feeds) not recycled back to source for next cash-
crop production cycle.
LARGE-SCALE NUTRIENT FLOWS
Recycling Nutrients & Organic Matter
Nutrient inputs
Food
Products
Manure
Cereal Production
Human
Consumption
Nutrients
O.M.
Annual
Mineral
Fertilizer
Additions
Nutrients & O.M. NOT recycled
Regional nutrient excesses
Wastes
Local Farm
Landfills
Reasons to
Recycle Livestock Nutrients
 Many confined livestock operations import more
nutrients than they export, resulting in localized
nutrient accumulations.
(US studies - NE, WA, PA) … not sustainable in long term.
 Can’t continue increasing N loadings in environment
& maintain current nitrate water quality standards.
 Human activities doubled global N fixation rate in 20th century.
(Barton & Atwater, U.B.C., 2002)
 In many countries, P is considered a non-renewable
resource – finite supply, some sources have high
heavy metal contents (e.g. Cd in phosphate from Idaho).
Whole Farm Nutrient Balances
(Budgets)
 Balancing Nutrient INPUTS & OUTPUTS
at farm-scale or at small watershed-scale.
– Next stage in Nutrient Management Planning &
Source Water Protection.
 As more precise nutrient management planning is
implemented, many farmers will discover nutrient
surpluses somewhere within their land base.
 Recent studies in U.S.A. show that majority of farms
studied have nutrient surpluses, esp. Nitrogen.
(INPUT/OUTPUT > 1.5)
(Koelsch & Lesoing, 1999; Cogger, 1999)
Managing
On-Farm Nutrient Surpluses

Three Options:
1.
Reduce nutrient inputs to balance nutrient
exports from the land base (e.g. improved feeding
strategies – nutrient use efficiency e.g. phytase).
2.
Increase land base for applying manure
nutrients (buy, rent more land or contract for
exporting excess manure; Exporting liquid manure
nutrients < 15 km radius (economics).
3.
Export surplus nutrients from the farm in the
form of value-added products (new revenue source
- organic fertilizers/amendments).
Exporting
Surplus Livestock Nutrients
 The need to export surplus nutrients will increase
with further intensification of livestock operations.

Conditions for exporting manure nutrients:
1. Odour-free
2. Pathogen-free
3. Dewatered (dried) for transportation
Manure processing can address these issues.
What is Manure Processing?
 …. “Treating the entire manure volume”
…. to reduce odours & pathogens.
Two best technologies:
 Anaerobic digestion – high cost, greater revenue
 Composting – low-cost, limited revenue
 Manure processing can provide the farmer with
increased flexibility for managing surplus nutrients,
by remediating key environmental problems.
Why Digest Manure?
Potential Benefits
Environmental
Economic
 Reduce odours & pathogens
- flexibility to export surplus nutrients
 Renewable energy generation
- energy independence
 Export surplus Livestock nutrients
 Conserve nutrients (N)
- reduce mineral fertilizer use
 Emission reduction trading credits
 Reduce gaseous emissions
- GHGs, ammonia, hydrogen sulfide
 Tipping fees – food-grade wastes
- 20 – 25% energy boost
Societal
 Reduce siting / zoning problems
Regain public support
 Opportunity for new rural partnerships
Balancing Issues
in a Sustainable Farming Operation
1. Yield/Productivity
(economics)
Pre-1965
Societal Concerns
2. Environmental Issues
Since 1970s  2-D
Both are science-based
3. Societal Concerns
Since 1990s  3-D
 Perception-based, emotional
 Can over-ride other 2 factors.
 Opposition difficult to reverse
once initiated
Anaerobic Digestion
A Few Facts
 Mimicking fermentation in a ruminant stomach.
(most digesters are mesophylic ~ 37°C – body temp.)
 Kills weed seeds – reduces herbicide use.
 pH often increases about 0.5 unit during digestion.
 Closed system – no nutrient or gaseous losses (e.g. N)
- closer N:P ratio than with raw manure – better for crops
 About 50% of carbon  biogas (CH4 + CO2, 65:35, tr. H2S);
- (nutrients in more plant available, predictable form)
(~ 25% C blown off conventional slurries by bacterial decomp.)
Anaerobic Digestion
…….. More Facts
 Certain antibiotics can HALT digestion processes
 Solids range: up to ~ 13% (easily pumpable)
 Hydraulic Retention Time: (processing time):
- 20–35 days @ 37°C
 Odour Reduction: ~ 90% or more
 Pathogens Reduced to:~ 1/1000 – 1/10,000 (mesophylic);
- Eliminate pathogens by pasteurizing (1hr @ 70°C)
Managing Dead Stock
A Waste + Nutrient Issue
 A waste issue that now costs the farmer to manage
– end products have lost their value since BSE crisis
– can’t recycle animal protein through feed system
e.g. bonemeal has lost much of its former value
 Current disposal methods have limitations
 Burial – limited capacity, point source pollution potential
 Incineration – N and C lost, minerals?; emission issues
renewable energy recovery possible
 Composting – cost recovery for composted solids
Managing Dead Stock
A Waste + Nutrient Issue
 Anaerobic Digestion – best solution for deadstock
and for animal rendering – 2 valuable end products
 Renewable energy recovery (heat, electricity)
 Organic solids end product (fertilizer, amendment)
 Conserves N, P & some C for recycling back to land
 Minimizes odour problems; eliminates pathogens
 Pre-Treat = shredder + Pressure/Temperature
- treated waste virtually all digestible
- possible elimination of BSE prions
Manure Processing
Anaerobic Digestion

Low Tech

High Tech
Barriers to Adoption of
Anaerobic Digestion Technology
1.
Investment, Incentive & Payback Issues
2.
Managing Regulatory Issues
3.
Developing Reliability, Trust & Expertise
4.
Managing Complexity
Overcoming Barriers
to Adoption of
Anaerobic Digestion Technology
1. Investment, Incentive & Payback Issues
 $300K - $5M, depending on scale of operation
– Plant Life = 20 – 30 yr before reconditioning
– Payback = <10 yr (electricity, solids sales, emission credits)
– Breakeven – 110 cow dairy; 1200 hog; 25,000 poultry
 Policy Issues – Need consistent policies & incentives
across 3 levels of government
- Environ. Loan Guarantees (manage risk)
- Tax Incentives for green electricity
 Feasibility Assessment - How does the farmer put a
realistic value on odour & pathogen-free manure
products? – changes from societal opposition to opportunities for
new partnerships.
Overcoming Barriers
to Adoption of
Anaerobic Digestion Technology
1. Establishing Revenue Streams
 Electricity Purchase Agreements
– Net Metering, Dual Metering – Peak Demand Generation
– Nova Scotia, Ontario, Saskatchewan - leading provinces
– may be sufficient to be energy independent;
delivered power ~ 2 x generating costs (ON = 12 - 15¢/kwh)
 Sale of Processed Solids/ Org. Fertilizers
– excess nutrients exported – promotes nutrient re-use
 Emission Trading System currently developing
- sell credits for reducing emissions
- current value of e-CO2 in Europe ~ $10/tonne
 Tipping Fees for Receiving Food-Grade Wastes
– boost biogas output (20 – 30%)  increases revenue
Overcoming Barriers
to Adoption of
Anaerobic Digestion Technology
2. Managing Regulatory Issues
 Electrical generation – interconnects / net metering
Power Utilities starting to change policies for small renewable
energy generators (up to 500 kw)
 Off-farm biomass inputs (boost biogas production)
can result in C. of A.s – regulations being changed to allow
<20% food-grade wastes
 Managing emissions / discharges
Biogas flare, fugitive GHGs, liquid discharges
 Fertilizer/amendment products - quality assurance,
certification; labeling requirements
Overcoming Barriers
to Adoption of
Anaerobic Digestion Technology
3. Developing Reliability, Trust & Expertise
 Small installed digester base in Canada
(12 – 18 in advanced design or already built)
 Limited knowledgeable Canadian design/build firms
- limited track record
 Demonstration Program – AAFC/NRCAN - 3 yr - Energy
Co-generation from Agricultural/Municipal Wastes (ECoAMu)
4 digesters (AB – Beef; SK – Hogs; ON – Beef; QC - Hogs)
ECoAMu Program On ManureNet
http://res2.agr.gc.ca/initiatives/manurenet/en/hems/ecoamu_main.html
Overcoming Barriers
to Adoption of
Anaerobic Digestion Technology
4. Managing Complexity
 A.D. adds yet another new technology to be
managed by farmer – Time; Skill-sets
 Service agreements
 Co-Generation – Power Utility – electricity export
 Remote monitoring & process control in realtime – practical technology now available
Integrated Livestock Farming System
Closed Loop Single Farm Energy Centre
Nutrient inputs
- 15% feed costs
<20% Off-Farm
Food-Grade Wastes
Nutrient
Recycling
Loop
Cereal
Production
Revenue #2
Electricity
Export
Anaerobic
Digester
Co-gen
Electricity
Revenue #1
Nutrient
Export
Non-Ag Uses
Home gardens
Turf/golf
Parks
Heat
Nutrient
Surplus
Organic
Fertilizer
CO2
Surplus
Co-Located
Industries
Bio-ethanol plant
Greenhouses
(Veg., Flowers)
Fish Farm
Local Farm
Revenue #3
Optional
A Centralized Co-op Rural Energy System
Potential Components
Dewatered
Digestate
Liquid
Digestate
Co-gen
Food Grade
Organics
water
Resource Centre
Electricity
Heat
Local
Municipal
Organics
Rendering,
Deadstock
Wet Distillers Grain - 15% savings
Organic
Fertilizers
CO2
Clean Water
Co-Located
Industries
Greenhouses
(Veg., Flowers)
Fish Farm
Slaughterhouse
Bio-ethanol plant
Challenges Facing
Confined Livestock Operations
Energy
 Increasing price volatility (The China factor)
 Less reliable supplies (Declining fossil reserves)
 Will also increase N fertilizer costs
Environment
/ Health
 Increasing regulations – nutrients, pathogens
 Municipal waste issues (biosolids)
 Rendering / deadstock – limited uses/value
 GHG emission reductions – Kyoto protocol
 Increasing livestock intensities – odour
Economics
 Continuing vulnerability of farm incomes
 Increasing costs of compliance
Re-Defining
Confined Livestock Farming
 Future livestock operations will be structured
around bio-energy  energy independence using
co-generation technologies.
 Facilitates conservation and recycling of resources
(nutrients, carbon = $$$)
 Income stabilization through diversification
 (new revenue streams independent from commodity prices!)
- Green Electricity
- Processed manure solids
- Emission Trading Credits - Co-located integrated industries
- Tipping fees for food-quality wastes (energy boost)
Re-Defining
Confined Livestock Farming
 Substantially reduces existing environmental issues
– reduced odours, pathogens  diminished societal concerns
– greater flexibility for applying/selling processed manure
 Strengthens rural economy utilizing more local inputs
(employment, resource inputs – biomass crops)
- Municipality can be a partner (wastes, buy energy)
- Farmer co-ops take increased control of rural businesses
ADD value to products BEFORE leaving farm gate
- Reduced transportation costs for manufacturing (bio-based)
Farm Bio-Energy Centres
As Integrators & Facilitators
GHG reductions
Deadstock
Income
Stabilization
Odours Environmental
Solutions
Pathogens
Nutrient
export &
Recycling
Farm Bio-Energy
A.D. Processing
Reduce
herbicide
use
Energy
Independence
Municipal
Organic wastes
Rural Revitalization
Heat
Electricity
Clean water
CO2
Electricity
Manure solids
Emission
credits
Tipping fees
Independen
t
of
Livestock
prices
Co-located industries
Local biomass inputs
In Summary
 A.D. manure processing is the key to:
 Remediating environmental problems (odours, pathogens)
 Improving community relations
 Providing flexibility for managing surplus nutrients
 Generating bio-energy (thermal, electrical)  energy
independence & rural business opportunities
 Economics are rapidly improving, but policies,
incentives & regulations need to be coordinated across
3 levels of gov’t to facilitate adoption of this technology.
 Efforts to increase technical support and assistance are
required to foster adoption of the technology.
Resource Information on
http://res2.agr.gc.ca/initiatives/manurenet/manurenet_en.html
 6,000 external web links
 Several hundred digital technical/research reports
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Manure Treatment
Digester Compendium
Nutrient Recovery
Ammonia Emissions
Nutrient Management
Environmental Issues
GHG Emissions
Odour Management
Land Application

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Storage & Handling
Housing / Feedlots
Feeding Strategies
Codes, Acts, Regulations
Health & Safety
Links
Digital Library
Expertise
Environmental Archive
(>165 digital reports)
Micro CHP
(Combined Heating and Power)
Distributed Power Generation
Electricity + Heat generated at each residence
Small engine + generator  replace furnace & water heater
85 % efficiency
Grid
Micro CHP
(Combined Heating and Power)
Distributed Power Generation
Centralized GasFired Plant
Micro CHP
100
100
57
<15
4-7
0
39
20
Useful Heat Energy
0
65
Net Useful Energy
36-39
85+
INPUT
Waste Energy
Line Losses
Electricity
Micro CHP
(Combined Heating and Power)
Advantages

More efficient use of resources (15% vs 60% loss)
(39 vs 85 % efficiency)






Micro CHP units run on natural gas or biogas
Excess electricity exported to grid (10 kw units - $$)
Blackout & Terrorist proof (totally distributed generation)
Significant GHG reductions
Almost eliminate line losses (electricity used on-site)
In Ontario – 2 million homes would produce 10,000 Mw
– equivalent to several nuclear power plants
No environmental assessments required – minor impacts
 Several thousand units being tested in Europe & Japan;
USA senate holding hearings on technology potential
