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Agri Clean David C. Palmer, P.E. Managing Partner. Cost-effective Anaerobic Digestion Technologies and Their Role in Green Power. AgriClean, LLC. An emerging leader in the areas of manure management & anaerobic digestion Not an outfit with an answer in search of a problem
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AgriCleanDavid C. Palmer, P.E.Managing Partner Cost-effective Anaerobic Digestion Technologies and Their Role in Green Power
AgriClean, LLC • An emerging leader in the areas of manure management & anaerobic digestion • Not an outfit with an answer in search of a problem • Rather, a solutions oriented company that can provide a least-cost customized method to meet customer needs • Specializing in dairy, swine and agricultural processing wastes • Energy Recovery AgriClean
AgriClean, LLC • Significant technological solutions • AgriJet process can significantly reduce water volumes used for flushing • AgriGas process can provide a tailored AD solution • AgriClean can optimize organic waste removal and treatment systems plus energy recovery AgriClean
Types of Digesters Used Depends on… • Type of waste (feedstocks) • Feedstock total solids (TS) concentration • Facility location • Management structure AgriClean
With Livestock Operations • Manure Management Systems • Traditional flushed barns have dilute total solids (less than 3%) • Scraped barns have higher total solids (greater than 3%) AgriClean
Flushing Example #1 AgriClean
Flushing Example #2 AgriClean
Anaerobic Digestion (AD) System Options • Suspended Growth Systems • Solids Retention Time = Hydraulic Retention Time (SRT = HRT) • Covered Lagoons • Complete Mix • Attached Growth Systems • SRT ≠ HRT • Fixed Film • Others in development pipeline AgriClean
AgriJet • Substitutes pressure for volume in hydraulic flushing operations • Can reduce water use by up to 80% in new facilities and 50% in existing facilities • Programmable control system set to flush at user-specified, such as milking times • All pipes, nozzles and gutters positioned to allow animal movement and to avoid breakage AgriClean
AgriJet • Depending on design criteria, AgriJet can deliver manure to the digester with up to 6% Total Solids • Greater Total Solids can significantly reduce AD system cost! • More organic loading = higher gas yields and greater energy potential AgriClean
AgriJet Dairy Farm Example • A 1,000 head dairy using standard hydraulic flushing techniques would use a flush volume of about 100,000 gallons/day • Conventional digester would require a volume of around 2,000,000 gallons • AgriJet system on the same farm will require 35,000 gallons/day for flushing • Fixed-film digester w/ a volume of 175,000 gallons • Other system aspects (pipes, heat exchangers, pumps, solids separators, etc.) are also made smaller AgriClean
AgriGas • AgriClean has several types of AD systems with gas capture in its portfolio • Covered lagoon • Fixed film AD licensed from the patent-holder • Continuously stirred (complete mix) AgriClean
Fixed Film AD System Development AgriClean
Fixed Film AD System Advantages • Designed for use w/ dairy manure, but also well suited for hog manure • Small footprint • 2-6 day HRT v. 20 days for suspended growth • Modular design • Deployed at ~30% less cost than suspended growth • High Methane yields • Up to 80% Methane v. ~60% for suspended growth • Very high destruction of Volatile Solids (VSd) • Up to 65% VSd w/ hog manure AgriClean
On-Farm Projects Underway • Fixed-film digester and biogas use system on a 400 head dairy (around 560 animal units or AU) near Hillsboro, MS in partnership with the Mississippi Alternative Energy Enterprise • Fixed-film digester and biogas use system on a swine finishing farm producing 30,000 animals/year (around 1600 AU at steady-state) near Greenville, NC in partnership with the Animal and Poultry Waste Management Center of NC State University • Fixed-film digester and biogas use system on a swine farrow-to-finish operation producing 64,000 animals/year (around 3580 AU at steady-state) in Canada • Covered lagoon digester and biogas use system on a 4000 head swine nursery farm in Montpelier, MS AgriClean
Ag Processing Plant Projects Underway • Fixed-film digester and biogas use system at a 1000 head/day beef packing plant • Covered lagoon digester with biogas capture at a 6000 head/day swine processing facility AgriClean
What is Green Power…? • Solar • Wind • Geothermal • Biomass AgriClean
What is Biomass…? • Wood, forestry residuals • Agricultural waste • Industrial waste • Municipal waste • Food processing residuals • Other organic by-products • Crops grown for energy production AgriClean
What isAnaerobic Digestion…? • A biological process that occurs in the absence of dissolved oxygen • Three temperature ranges for AD • Psychrophilic (ambient…swamps, sediments of lakes and ponds, landfills, intestines of animals) • Mesophilic (95-105 degrees F) • Thermophilic (125-135 degrees F) AgriClean
How is Biogas Produced? • Microbiological conversion of organic wastes into methane, carbon dioxide and trace elements like hydrogen sulfide • Amount and quality of biogas depends on the composition and biodegradability of the feedstock AgriClean
How is the biogas used to create energy? • Most efficient use is to replace other fuel sources like natural gas or propane • The gas can also be used to fuel engine generators or microturbines to produce electricity • In some cases the gas is used to fuel vehicles AgriClean
Utility Issues • Interconnection agreements • System and generation protection requirements • Normal and emergency operating provisions • Metering • Cost and ownership • Power sales agreements AgriClean
Harris Farm Project Overview • Under contract from the NCAG Smithfield/Premium Standard Farms Agreement for Environmentally Superior Technologies through NCSU’s Animal and Poultry Waste Management Center • Projected economics to be at or below the costs of current lagoon/sprayfield-based treatment systems • Farm owner agreement allows for the retained ownership of the system by AgriClean AgriClean
Harris Farm Project Overview • 12,000 head finishing farm • Animals are added in two barns every two weeks • LAW remains fairly constant; w/ tank heated @ 35°C, biogas production should not vary significantly • Barns use a pit recharge, pull plug flushing system • Flushing schedule is every 3 days • Daily flow now in excess of 240,000 gpd • 20,000 g/barn/day • Changed flush schedule & AgriJet system indicates the use of 30,000 gpd for flushing and 18,000 gpd of flow from the animals • 4,000 g/barn/day AgriClean
Harris Farm Project Overview • Organic loading used to establish initial volume • COD is controlling factor • Based on the lab analyses, digester loadings at 48,000 gpd will be: ComponentConcentration (mg/l)Pounds TS 25,216 10,079 VS 21,490 8,589 COD 40,227 16,079 TKN 2,880 1,151 AgriClean
Harris Farm Project Overview • Farm connected to the electrical grid • Sales agreement to sell peak power to Greenville Utilities from existing diesel engine/generators • Current plan is to offset the increased farm load resulting from the waste treatment facility • Present utility rates and standby charges in North Carolina make it uneconomical to sell excess power • Exploring using the biogas to meet farm’s existing peaking contract • May provide an economical sales structure to sell peak power from the biogas AgriClean
What are the economics of producing Green Power from Anaerobic Digestion? • It costs about 6.5 cents per KWh to produce electricity from AD • In most parts of the country, the price utilities will pay for this renewable energy is about half what it costs to produce it • Currently the environmental benefits of AD (odor control, water, air and land pollution reduction) are the driving factors in selecting this as a preferred waste treatment option AgriClean
How can utilities encourage the development of this source of Green Power? • Progress Energy has a target of 5% of its load from Green Power (about 1,100 MW) • Some others have targets as high as 25% • TVA and its distributors offer a Green Power Switch program including solar, wind and biomass AgriClean
AgriClean Contacts • Nashville TN, David Palmer @ 615-279-9797 Scott Pogue @ 615-594-8657 • Pierre SD, Phil Lusk @ 605-224-4334 • agriclean@agriclean.com AgriClean