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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
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Re-Defining Confined Livestock Farming:Making Carbon Work for UsBruce T. BowmanExpert Committee on Manure ManagementCanadian Agri-Food Research CouncilPresented at:CARC Annual MeetingOttawa, OntarioApril 21, 2005
Presentation Objective To demonstrate the central role of manure processing & farm bio-energy systems for revitalizing rural economies - GHG’s - Odours- Pathogens - Deadstock NutrientIssues Environmental Remediation - Conservation - Recycling - Nutrient availability A.D.Manure Processing Farm Economic Benefits Rural Society Benefits Farm Bio-Energy
Priority Issuesfor 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.
Food Products Human Consumption Cereal Production Nutrients O.M. Manure Wastes Local Farm Landfills LARGE-SCALE NUTRIENT FLOWS Recycling Nutrients & Organic Matter Nutrient inputs Annual Mineral Fertilizer Additions Nutrients & O.M. NOT recycled Regional nutrient excesses
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 & OUTPUTSat 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: • Reduce nutrient inputsto balance nutrient exports from the land base(e.g. improved feeding strategies – nutrient use efficiency e.g. phytase). • Increase land basefor applying manure nutrients (buy, rent more land or contract for exporting excess manure;Exporting liquid manure nutrients < 15 km radius (economics). • Export surplus nutrientsfrom 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: • Odour-free • Pathogen-free • 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 withincreased flexibility for managing surplus nutrients, by remediating key environmental problems.
Environmental Reduce odours & pathogens- flexibility to export surplus nutrients Conserve nutrients (N)- reduce mineral fertilizer use Reduce gaseous emissions- GHGs, ammonia, hydrogen sulfide Economic Renewable energy generation- energy independence Export surplus Livestock nutrients Emission reduction trading credits Tipping fees – food-grade wastes - 20 – 25% energy boost Why Digest Manure?Potential Benefits Societal • Reduce siting / zoning problemsRegain public support • Opportunity for new rural partnerships
Yield / Productivity Environmental Issues Societal Concerns Balancing Issuesin a Sustainable Farming Operation • 1. Yield/Productivity (economics)2. Environmental Issues • Both are science-based Pre-1965 Since 1970s 2-D • 3.Societal Concerns • Perception-based, emotional • Can over-ride other 2 factors. • Opposition difficult to reverse once initiated Since 1990s 3-D
Anaerobic DigestionA 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 StockA 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 systeme.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 StockA 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 ProcessingAnaerobic Digestion • Low Tech • High Tech
Barriers to Adoption ofAnaerobic Digestion Technology • Investment, Incentive & Payback Issues • Managing Regulatory Issues • Developing Reliability, Trust & Expertise • Managing Complexity
Overcoming Barriersto Adoption of Anaerobic Digestion Technology • 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 Barriersto Adoption of Anaerobic Digestion Technology • 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 Barriersto Adoption of Anaerobic Digestion Technology • Managing Regulatory Issues • Electrical generation– interconnects / net meteringPower 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 / dischargesBiogas flare, fugitive GHGs, liquid discharges • Fertilizer/amendment products - quality assurance, certification; labeling requirements
Overcoming Barriersto Adoption of Anaerobic Digestion Technology • 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 Barriersto Adoption of Anaerobic Digestion Technology • 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 real-time – practical technology now available
- 15% feed costs Revenue #2 Electricity Export Anaerobic Digester Cereal Production CO2 Heat Revenue #1 Nutrient Export Nutrient Surplus Organic Fertilizer Electricity Integrated Livestock Farming System Closed Loop Single Farm Energy Centre Nutrient inputs <20% Off-Farm Food-Grade Wastes Nutrient Recycling Loop Co-gen Surplus Co-Located Industries Bio-ethanol plant Greenhouses (Veg., Flowers) Fish Farm Non-Ag Uses Home gardens Turf/golf Parks Local Farm Revenue #3 Optional
CO2 Resource Centre Electricity Heat Clean Water Local MunicipalOrganics Rendering, Deadstock A Centralized Co-op Rural Energy System Potential Components DewateredDigestate Organic Fertilizers LiquidDigestate water Co-gen Food GradeOrganics Co-Located Industries Greenhouses (Veg., Flowers) Fish Farm Slaughterhouse Bio-ethanol plant Wet Distillers Grain - 15% savings
Challenges Facing Confined Livestock Operations • Increasing price volatility(The China factor) • Less reliable supplies(Declining fossil reserves) • Will also increase N fertilizer costs Energy Environment / Health Economics • Increasing regulations – nutrients, pathogens • Municipal waste issues (biosolids) • Rendering / deadstock – limited uses/value • GHG emission reductions – Kyoto protocol • Increasing livestock intensities – odour • Continuing vulnerability of farm incomes • Increasing costs of compliance
Re-DefiningConfined 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 CentresAs Integrators & Facilitators Electricity Manure solids Emission credits Tipping fees GHG reductions Deadstock Income Stabilization Environmental Solutions Odours Pathogens Nutrient export & Recycling Reduce herbicide use Independent of Livestock prices Heat Electricity Clean water CO2 Farm Bio-Energy A.D. Processing Energy Independence Rural Revitalization Municipal Organic wastes 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 • Manure Treatment • Digester Compendium • Nutrient Recovery • Ammonia Emissions • Nutrient Management • Environmental Issues • GHG Emissions • Odour Management • Land Application • 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
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