Content. CAFOs. CAFOs. Improvements Needed. Manure Characteristics. Making the Most of Manure: Emerging Waste-to-Energy Treatments 4/13/2009

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1 4/13/29 Making the Most of : Emerging Waste-to-Energy Treatments Keri B. Cantrell, Kyoung S. Ro, Patrick G Hunt USDA-ARS Coastal Plains, Water, and Plant Research Center Florence, SC 2951 Isabel M. Lima USDA-ARS Southern Regional Research Center New Orleans, LA 7124 Content CAFO and Introduction Thermochemical Technology Advantages Thermochemical Technologies Direct Liquefaction Wet Proposed System Designs March 25 th, 29 CAFOs CAFOs Decrease in number of farms with increase in size pigs or farms Limited Land Availability via Traditional Management Practice NC Hogs and Pigs, NASS-USDA 1,537, TONS dry manure Pigs Farms Decrease in number of farms with increase in size Limited Land Availability via Traditional Management Practice Storage Land Application Relatively low capital and O&M costs Improvements Needed Surplus from CAFOs greater than crop nutrient demand Transporting manure to remote crop fields Lagoon sludge Potential environmental risk H 2 S, NH 3, and CH 4 from storages Odors Potential contamination of ground and surface waters Energy not utilized Characteristics Poultry Litter [i] Dry s - Surfaced Feedlot [ii] Paved- Surfaced Feedlot [ii] Wet s Flushed Swine [iii] Flushed Dairy TS (%) [iv] VS (% of TS) Ash (% of TS) Fixed Carbon (%TS) NA Carbon Content (% db ) [v] [i] Cantrell, K.B. et al. Beltwide Cotton Conf. Paper No. 8996, 29. [ii] Sweeten, J.M. et al. ASABE Paper No , 26. [iii] Cantrell, K.B. et al. ASABE Paper No , 27. [iv] Chastain, J.P. et al. Appl. Eng. Agric. 21, 17(3): 343. [v] Young, L.; Pian, C.C.P. Energy. 23, 28,

2 4/13/29 Heating Values U/lbTSdry) HHV (BTU Poultry Litter - Surface Feedlot Paved- Surface Feedlot Swine Flushed Dairy HHV (BTU/lb TSdry) Ash (%TS) Ash (% %TSdry) Management Practice Reduce CAFO environmental impact Remove large amounts of organic waste Harness inherent energy to produce energy-dense, alternative fuels Research Focus Identify viable TCC technologies for treatment of animal waste Adapt this technology to be used on-farm Lead to providing a source of additional energy and value-added products Biomass Energy Conversion Pathways Biomass Feedstock Biological Conversion Thermochemical Conversion Heat/Power Alcohols Diesels Methane Thermochemical Conversion (TCC) Technology High temperature chemical reforming Organic bonds broken Intermediates reformed into synthesis gas and hydrocarbon fuels Minor residual of minerals and fixed carbon TCC Technology Advantages Requires Smaller Footprint Compact design with shorter processing time 2

3 4/13/29 TCC Technology Advantages Requires Smaller Footprint Reduces Disposal Requirements Mass consumer of feedstock More animals per land unit TCC Technology Advantages Requires Smaller Footprint Reduces Disposal Requirements Multiplicity of End Products & Applications Heat & power generation Chemical feedstocks Transportation fuels Industrial applications Future carbon trading TCC Technology Advantages Requires Smaller Footprint Reduces Disposal Requirements Multiplicity of End Products and Applications Including Energy Provides Socio-Environmental Benefits Fresh/clean air Potable water Pathogen, pharmaceutical, and nuisance gas elimination TCC Technologies Direct Liquefaction Wet Conversion of organic material with no oxygen : End Products Syngas Chemical Feedstocks Biomass: Waste Residues Syngas Bio-oil Biomass: Waste Residues Bio-oil oil Char, (Charcoal) (Biochar) Liquid Fuels Bioenergy Feedstock Char (Biochar), Ash Combined Heat & Power 3

4 4/13/29 Mode Fast Intermediate Conditions ~5C; vapor residence time ~1 sec ~5C; vapor residence time ~1-2 sec Liquid (Bio-oil) Wt% Char Gas Biomass: Waste Residues Char, (Charcoal) (Biochar) Activated Carbon Bioenergy Feedstock ~4C; vapor residence time ~hrs Carbon Sequestration Bridgwater, 27 Pellet Mill Furnace Pelletized Char and Activated Carbon Making Dried poultry manure 1-2 %wb Cross beater Mill < #1 mesh Pellet Mill 3/16 dia pellets N 2 Steam Acid wash Unwashed GAC 2 35% yield Activation Rinse ~ 4% yield Drier washed GAC Screen/sieve Heat, time 1-3% yield Activated Carbon/Char Unwashed char Syn-gas Bio-oil Activated Carbon: Physical Properties Yield % Surface Area m 2 /g Attrition % Broiler Litter Broiler Cake Turkey Litter Turkey Cake Duck PUR RF Coal Coconut Shell Wood Activated Carbon: Metal Ion Adsorption mg-metal/g-carbon Cu 2+ Cd 2+ Zn 2+ Broiler Litter Broiler Cake Turkey Litter Turkey Cake Minimal adsorption for activated carbon from coal, wood, or coconut shells Lima and Marshall, 25 4

5 4/13/29 NH 3, ppm. Activated Carbon: NH 3 Adsorption Linear relationship between Bed Depth and NH 3 Breakthrough Time Channel 1 Channel 2 Channel 3 e Time (min). Service y = x R 2 = % Removal Bed Depth (cm) Biomass: Waste Residues Char, (Charcoal) (Biochar) Activated Carbon Bioenergy Feedstock Carbon Sequestration Elapsed time, min Raw Stable product Biochar Production Little to no volatile material remaining Biochar Energy content increase 3-5% Bench-scale production Separated swine solids Pyrolyzed under N 2 at 5 C; no activator Biochar Application amendment Bio-charcoal and poultry litter Test potential to: Increase carbon content Build aggregation Source: J.M. Novak, USDA-ARS Charcoal added to soil for lab incubation study. Energy Balance for Carbonizing Cellulose Can we carbonize wet livestock wastes with positive energy budget? 3912, 51% 516, 7% Cellulose Heating Value: 748 BTU/lb 387, 5% 129, 2% 278, 35% Biochar HHV Gas HHV Expansion of Gas Sensible Heat Heat of Reaction Antal, Jr. et al. (23) Ind. Eng. Chem. Res 5

6 4/13/29 Drying Energy Wet manure like 12 dairy and swine 1 require energy 8 input to dry 6 Decreases available energy of biochar for alternative uses ergy (BTU/lb dry) Drying Ene 4 2 % 2% 4% 6% 8% 1% Solids Content Drying Ene ergy (BTU/lb dry) , 51% 278, 35% Biochar HHV 129, 2% Gas HHV 516, 7% Expansion of Gas 387, 5% Sensible Heat Heat of Reaction Energy from gas (27 BTU) can be used to dry swine manure with > 3% solid 278 BTU % 2% 4% 6% 8% 1% Solids Content Drying Ene ergy (BTU/lb dry) BTU 278 BTU 3912, 51% 516, 7% 387, 5% 129, 2% Additional energy from charcoal (39 BTU) can be used to dry swine manure with < 3% solid, but not less than 14% solid. 278, 35% Biochar HHV Gas HHV Expansion of Gas Sensible Heat Heat of Reaction % 2% 4% 6% 8% 1% Solids Content Direct Liquefaction Direct Liquefaction Aqueous feedstock Oxygen-limited atmosphere Pressurized environment 5 to 2 MPa Bio-oil desired product ~7% Wet Direct Liquefaction Dry (air-blown) Wet Process Air, water, and oxygen serve as oxidizers Temperature range 8-1 C 6

7 4/13/29 Process 3 Main Stages HEAT Drying Volatilization 1-15 C C 7-13 C Oxidizers Low-grade gas Less than 5MJ/m 3 Natural gas: 37 MJ/m 3 Severely diluted with N 2 (~6%) H 2 :CO vary Steam Volatiles NCG Gas Phase Reactions Ash Produc t Gases Minor amounts of CH 4 Residual solid product Depends on ash content : Enhancements Steam Injection Improved gas quality with increased H 2 Decreased char formation Catalyst Addition Examples: Langbeinite, Alkali Salts Improve synthesis gas quality and production CO 2 production cut in half Increase gasification rate Complete fixed carbon conversion Wet Catalytic Hydrothermal Processing Pacific Northwest National Laboratory (D. Elliott et al.) 25 to 36 C and up to 22 MPa (215 atm) Ru catalysts Tested with dairy manure Elliott et al., 24 9% Heat recovery Wet : Products Wet System Biomass CH 4 : 55 % CO 2 : 45% Oils, Tars Heat-Treated Water Wet Biomass Heat Exchange/ Recovery Pressure Letdown htr Catalytic Reactor, 35 C 2 atm CH 4 & CO 2 Gas/Liquid Separation Char, Ash Electricity Water, NH 3, Salts Ro et al., 27 7

8 4/13/29 Energy Generation No Heat Recovery Energy Generation 9% Heat Recovery Net Energy Generation (kj/kg kg-dm) 2 Swine Feedlot 15 Pumpable Solid Concentration Range 1 Dairy Poultry 5 % 1% 2% 3% 4% 5% -5 Solid Concentration (%TS) Wet Combustion Swine Swine Dairy Dairy Poultry Litter Poultry Litter Unpaved Feedlot Unpaved Feedlot Paved Feedlot Paved Feedlot (kj/kg DM) Net Energy Generation ( Pumpable Solid Concentration Range Energy neutral at TS 1-2% Swine Dairy % 1% 2% 3% Solid Concentration (%TS) Poultry Swine Dairy Poultry Litter Ro et al., 27 Ro et al., 27 Gas Comparison Gas Comparison 5 Wet vs. Anaerobic Digestion 4 Model 5 sow, farrowto-wean farm Waste stream: 13,8 gpd lb VS/d r Output (kw) Power 1 Wet Total Evolved Gas Power Engine Power Output (2% Efficiency) Anaerobic Digestion Cantrell et al., 27 Modeled reactions Methane Concentration 53% - Wet 68% - Anaerobic Digestion VS-Carbon Conversion to Gas >99% - Wet 64% - Anaerobic Digestion r Output (kw) Power Wet Total Evolved Gas Power Engine Power Output (2% Efficiency) Anaerobic Digestion Double the available gas for energy production Minimal residue removal Cantrell et al., 27 Proposed Wet Swine Management System USDA-ARS Liquid Waste Treatment System Meat Ash Combined Heating & Power Livestock House Wet CH 4 & CO 2 Livestock Water Recycle NH 3 Capture Fertilizer Solids Separation Flush Water Livestock House Compost Nitrification/ Denitrification Consumables Pathogen-free Water Recycle Phosphorus Removal Steam Reforming/ Partial Oxidation Catalytic TCC Liquid Fuels Fertilizer Vanotti and Szogi, 28 8

9 4/13/29 USDA-ARS Liquid Waste Treatment System USDA-ARS Liquid Waste Treatment System Meat CHP Flush Water Livestock House Pathogen-free Water Recycle H 2 & CO Liquid Fuels Solids Separation Nitrification/ Denitrification Phosphorus Removal Residue Fertilizer USDA-ARS Liquid Waste Treatment System Bio-Thermochemical Waste Treatment System CHP Consumables H 2 & CO Residue Liquid Fuels Microbial Conversion Livestock House Solids Separation Water Recycle N-Removal Green Coal Bio-char Bioenergy Feedstock Biogas (CH 4, H 2 ) Compost/ Land Application Gas Heat CHP Bio-Thermochemical Waste Treatment System Considerations Microbial Conversion Biogas (CH 4, H 2 ) CHP Consumables Livestock Water Recycle House Solids N-Removal Separation Drying Heat Gas Bio-char Many designs still in R&D stages Process Implementation Efficient heat recovery/exchange for drying manures High pressure delivery Depressurization avoidance Plugging Robust catalyst Efficient recovery of nitrogen Simple, safe, and robust operation 9

10 4/13/29 Considerations Feedstock Conditioning and Characterization Solid Separation, Dewatering, and Drying Grinding, Blending, and Pelletizing Smaller, uniform particles aid efficiency and consistency Sulfur and ash removal Bed agglomeration Silica-based sticky phase Next Generation Systems Effectively extract manure energy Eliminate ground and surface water contamination Nitrogen recovery potential Phosphorous h concentrated t in char/ash h Substantial fugitive gas and odor removal Heat-treated recycled wastewater Destruction of pathogens, pharmaceuticals, and estrogens Thank You Dr. Keri Cantrell USDA-ARS Coastal Plains, Water, and Plant Research Center 2611 W. Lucas St. Florence, SC 2951 keri.cantrell@ars.usda.gov 1