Presentation on theme: "Re-Defining Confined Livestock Farming: Making Carbon Work for Us Bruce T. Bowman Expert Committee on Manure Management Canadian Agri-Food Research Council."— Presentation transcript:
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
Farm Bio-Energy A.D. Manure Processing Rural Society Benefits Farm Economic Benefits Presentation Objective To demonstrate the central role of manure processing & farm bio-energy systems for revitalizing rural economies - GHGs - Odours - Pathogens - Deadstock - Conservation - Recycling - Nutrient availability Environmental Remediation Nutrient Issues
Water volumes Carbon = Energy $$$ Three priority issues to manage: Nutrients Odours Pathogens Priority Issues for Manure Management............................. but also …….
Two major loss pathways: As volatile ammonia (NH 3 ) - Adjust pH to near 7.0 to minimize ammonia losses - Rapid losses from freshly-exposed manure As nitrous oxide (N 2 O) - Processed manure less N 2 O emissions following land application – 50% less C (energy) for microbes) Conserving Nutrients: Gaseous Nitrogen losses from Manure In this section I will be developing linkages between nutrient conservation/recycling and manure processing.
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 LARGE-SCALE NUTRIENT FLOWS Recycling Nutrients & Organic Matter Annual Mineral Fertilizer Additions Nutrients & O.M. NOT recycled Regional nutrient excesses Local Farm Manure Nutrients O.M. Wastes Landfills Nutrient inputs
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. Cant continue increasing N loadings in environment & maintain current nitrate water quality standards. Human activities doubled global N fixation rate in 20 th 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). Reasons to Recycle Livestock Nutrients
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) Whole Farm Nutrient Balances (Budgets)
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). Managing On-Farm Nutrient Surpluses
Conditions for exporting manure nutrients: 1. Odour-free 2. Pathogen-free 3. Dewatered (dried) for transportation Manure processing can address these issues. Exporting Surplus Livestock Nutrients The need to export surplus nutrients will increase with further intensification of livestock operations.
…. 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. What is Manure Processing?
Environmental Reduce odours & pathogens - flexibility to export surplus nutrients Conserve nutrients (N) - reduce mineral fertilizer use Reduce gaseous emissions - GHGs, ammonia, hydrogen sulfide Societal Reduce siting / zoning problems Regain public support Opportunity for new rural partnerships 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
Yield / Productivity Environmental Issues Societal Concerns Balancing Issues in a Sustainable Farming Operation 1. Yield/Productivity (economics) 2. Environmental Issues Both are science-based 3. Societal Concerns Perception-based, emotional Can over-ride other 2 factors. Opposition difficult to reverse once initiated Pre-1965 Since 1970s 2-D Since 1990s 3-D
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 (CH 4 + CO 2, 65:35, tr. H 2 S); - (nutrients in more plant available, predictable form) ( ~ 25% C blown off conventional slurries by bacterial decomp.) Anaerobic Digestion A Few 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) Anaerobic Digestion …….. More Facts
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 – cant 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
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) Managing Dead Stock A Waste + Nutrient Issue Pre-Treat = shredder + Pressure/Temperature - treated waste virtually all digestible - possible elimination of BSE prions Conserves N, P & some C for recycling back to land Minimizes odour problems; eliminates pathogens
High Tech Manure Processing Anaerobic Digestion Low Tech
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
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 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) 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 real- time – practical technology now available Overcoming Barriers to Adoption of Anaerobic Digestion Technology
Revenue #2 Electricity Export Revenue #1 Nutrient Export Integrated Livestock Farming System Closed Loop Single Farm Energy Centre Local Farm Organic Fertilizer Non-Ag Uses Home gardens Turf/golf Parks Nutrient Surplus Co-Located Industries Bio-ethanol plant Greenhouses (Veg., Flowers) Fish Farm Cereal Production - 15% feed costs Revenue #3 Optional Nutrient Recycling Loop Anaerobic Digester <20% Off-Farm Food-Grade Wastes Nutrient inputs Co-gen Surplus Electricity Heat CO 2
Resource Centre Electricity Clean Water HeatCO 2 Co-Located Industries Greenhouses (Veg., Flowers) Fish Farm Slaughterhouse Bio-ethanol plant A Centralized Co-op Rural Energy System Potential Components Liquid Digestate Dewatered Digestate Food Grade Organics Local Municipal Organics Rendering, Deadstock Organic Fertilizers water Co-gen 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 Continuing vulnerability of farm incomes Increasing costs of compliance Increasing regulations – nutrients, pathogens Municipal waste issues (biosolids) Rendering / deadstock – limited uses/value GHG emission reductions – Kyoto protocol Increasing livestock intensities – odour Energy Environment / Health Economics
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) Re-Defining Confined Livestock Farming
Electricity Manure solids Emission credits Tipping fees Heat Electricity Clean water CO2 Municipal Organic wastes Co-located industries Local biomass inputs Odours Pathogens Nutrient export & Recycling Reduce herbicide use GHG reductions Deadstock Farm Bio-Energy Centres As Integrators & Facilitators Environmental Solutions Income Stabilization Rural Revitalization Farm Bio-Energy A.D. Processing Energy Independence Independen t of Livestock prices
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 govt 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 Grid 85 % efficiency
Micro CHP (Combined Heating and Power) Distributed Power Generation Centralized Gas- Fired Plant Micro CHP INPUT 100 Waste Energy 57<15 Line Losses 4 - 70 Electricity 3920 Useful Heat Energy 065 Net Useful Energy 36-3985+
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 Micro CHP (Combined Heating and Power) Advantages