Animal Operations and Air Quality Jan. 18 th, 2011 Zifei Liu Research Associate Departments of Animal Science and Biosystems & Agriculture Engineering
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 2
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 3
Agriculture: Satisfying the demand for food (Anders, 2010) 4
Increased human population is driving changes in crop and animal production methods Increased human population Increased consumption of animal protein Concentrated animal feeding operations (CAFO) 5
Changes in Agricultural Production The good old days Family farm system Small operations Resources were cycled: a closed loop for most nutrients Low productivity Modern systems Farms grew larger Became specialized Productivity increased Nutrients concentrated in certain regions Disconnected nutrient cycle feed animal feed animal crop manure crop manure? land land 6
Atmospheric emissions, transport, transformation, and deposition of trace gases (Aneja, et al., 2006) 7
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 8
Air emissions from animal production Odor NH 3 Animal production PM GHG H 2 S VOC 9
Air emissions from animal production Animal production Odor NH 3 PM GHG Often show at the top of air pollution complaints on animal operations Byproduct of microbial decomposition of animal waste Hundreds of compounds Interactive effects Subjective Odor VOC H 2 S NH 3, H 2 S VOCs, PM 10 10
Air emissions from animal production Animal production Odor VOC NH 3 PM GHG H 2 S Environmental impacts Eutrophication (Excess N deposition) Soil acidification (Nitrification processes) Aerosol formation (Fine particle precursor) Health effect Byproduct due to the relatively inefficient conversion of feed N into animal product 11
NH 3 The conversion efficiency of N in animal production may range from 20 to 40% (Rotz, 2004). Losses Farm boundary N Inputs Feed Manure Managed N Outputs 12
Air emissions from animal production Animal production Odor NH 3 PM GHG PM10 and PM2.5 Coarse particles tend to be deposited in the upper airways of the respiratory tract. Fine particles can reach and be deposited in the smallest airways (alveoli) in the lungs. H 2 S VOC 13
Primary particles Feed handling, animal activity, waste, road dust (fugitive) Secondary particles SO 2, NO x NH 3 Ammonium (NH 4+ ) aerosols 14
Air emissions from animal production Animal production Odor NH 3 PM GHG GWP of major GHGs CH 4 : 23 N 2 O : 298 CO 2 : 1 CO 2 generated by animal biogenic in nature or carbon neutral H 2 S VOC 15
Air emissions from animal production Odor Produced as manure decomposes anaerobically Animal production NH 3 PM GHG H 2 S Toxic at high levels (workplace limits set at 10 ppm) Possible chronic health impact from low, long-term exposure (some states limit property line levels to 0.05-0.1 ppm) VOC 16
Air emissions from animal production Animal production Odor VOC NH 3 PM GHG H 2 S Formed as intermediate metabolites in the degradation of organic matter in manure. Under aerobic conditions, oxidized to CO 2 and water Under anaerobic conditions, converted to CH 4 and CO 2 Odorous Health effect Participate in atmospheric photochemical reactions Precursors to O 3 and PM 2.5 17
Importance of Emissions at Different Spatial Scales Emissions Global, Regional Local, Property Line Primary Effects of Concern Odor * **** Nuisance, quality of life VOC *** ** Odorous, ozone formation H 2 S * *** Odorous, health NH 3 **** ** Atmospheric deposition PM * *** Health, haze GHG *** * Global climate change (NRC, 2003) 18
Regulating air emissions from animal operations If the emissions reach specified thresholds Permitting requirements Reporting requirements Clean Air Act (CAA) Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Emergency Planning and Community Right-to-Know Act (EPCRA). 19
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 20
PM10 sampling inlet PM measurement Cyclone to collect PM2.5 Filter (FRM) Sample inlet Flow Measurement and Control TEOM Beta gauge 21
PM2.5 Chemical Speciation Sampler PM 2.5 impactor Denuder Partisol 2300 sampler Filter holder PTFE filter: PM 2.5 mass and elements EDXRF Nylon filter: ion species IC Quartz filter: OC & EC NIOSH 5040 thermo-optical method 22
Cascade Impactors 23
A chamber method used for lagoon NH 3 sampling (Aneja et al., 2000) 24
Open-path sampling: optical detection device (Amon et al., 1997) 25
Odor sampling and measurement Sampling bag Olfactometry or Sampling canister or GC - MS 26
The challenges Accurate quantification of farm emissions is not an easy task because: Air emissions from individual farm can vary a lot depending on many factors; Direct measurements of emissions from each individual farm are expensive and difficult. 27
Emission factors The mass of the pollutants emitted per animal unit per year Most local, state, and federal agencies rely on emission factors to develop emission inventories Represents the sum of the annual mean emission rates from housing, manure storage/ treatment and land application; based on average annual conditions and typically a composite of various animal sizes and types. 28
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 29
The National Air Emissions Monitoring Study (NAEMS) In order to ensure compliance with regulation requirements and create a national methodology for estimating AFO air emissions Under the Air Consent Agreement with 2,600 participating AFOs. Measure air emissions at 24 sites (Covers all major types of swine, dairy and laying hen facilities) in nine states over a two-year period (2007 to 2009) Measurements include: PM, NH 3, H 2 S and VOC 30
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NAEMS Monitoring Plan Layer houses (NC2B site) Barn 3 Stage 1 Fans Barn 4 Instrument shelter Static pressure port Thermocouple S Solar sensor Anemometer RH/Temp probe Air sampling Exhaust fan Activity sensor PM monitor Air inlet Heated raceway Current switch Wind sensor RPM sensor 32
NAEMS Monitoring Plan Layer houses (NC2B site) Barn 3 High Rise Barns (18 m x 175 m) Barn 4 Instrument shelter Static pressure port Thermocouple S Solar sensor Anemometer RH/Temp probe Air sampling Exhaust fan Activity sensor TEOM Air inlet Heated raceway Loadout doors Wind sensor 33
Biological and Agricultural Engineering, North Carolina State University Tunnel ventilated barns with 17-48 fans on both ends of each barn 34
On-Farm Instrument Shelter Heated race way OFIS Heated race way Heated race way Gas tanks Inside the instrument shelter 35
NAEMS Housing Emission Data Species NH 3 H 2 S g/d-head uncertainties g/d-head uncertainties Sow gestation 6.5-29.4 13-35% 0.3-8.5 13-77% Farrow 1.9-10.0 28-77% 3.8-7.6 28-77% Finishing swine 6.7-8.4 12-18% 0.23-0.85 13-18% Dairy 5.0-56.5 7-28% 0.9-4.9 7-22% Hens - High rise 0.63-1.12 6-26% 0.001 12-14% Hens - Manure belt 0.28 21% 0.002 17% Broilers 0.47-0.54 17% 0.003 18% 36
NAEMS Housing Emission Data Species PM10 VOC g/d-head uncertainties g/d-head uncertainties Sow gestation 0.28-0.48 16-35% 1.8-7.2 - Farrow 1.17-1.67 30-67% 10.4-12.1 - Finishing swine 0.18-0.29 12-17% 0.6-5.5 - Dairy 0-10.3 8-49% 12-197 - Hens - High rise 0.016-0.038 9-29% 0.03-0.34 - Hens - Manure belt 0.008-0.025 22% 0.03-0.04 - Broilers 0.044-0.045 15% 0.10-0.13-37
Conservative animal numbers to meet EPCRA NH 3 thresholds 100 lb/day Species Housing emissions only Sows 1,500 7,000 Finishing swine 5,400-6,800 Dairy 800-9,100 Hens 40,000 162,000 Broilers 84,000-97,000 38
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 39
Carbon footprint A carbon footprint is a measure of the impact of our activities on the environment, and in particular climate change. It is the total GHG emissions caused directly and indirectly by the activities The carbon footprint is typically given in CO2 equivalent units. 40
Carbon Footprint of Dairy and Cars 20 lb CO2-eq per gallon of gasoline 17.6 lb CO2-eq per gallon of milk (Source: M. L. Walser, 2010) (Source: University of Arkansas Applied Sustainability Center) 41
Different voices Animal production produce more GHG (18%) than transport system (13.5%). (FAO, 2006) Animal production contributes less than 3% to the total US carbon footprint, compared to 26% from transportation. (EPA, 2009)? Researchers claimed that the FAO study is giving an inaccurate impression of the impact livestock production may have (Pitesky et al., 2009) Deforestation contributes over 35% to the FAO estimate of livestock production carbon footprint 42
GHG emission inventories The Intergovernmental Panel on Climate Change (IPCC) has developed guidelines for estimating and reporting emissions of GHG from AFOs (IPCC, 2006) Official GHG inventories are reported annually by each country to the United Nation Framework Convention on Climate Change (UNFCCC). The Kyoto protocol restricts the total GHG emissions of each signature country and the protocol provides an opportunity for emission trading within signature countries. 43
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 44
Estimating CH 4 emission using the IPCC approaches Manure CH 4 emission Enteric fermentation CH 4 emission Total CH 4 emission =VS B o 0.67 MCF Excreted volatile solid maximum CH4 producing capacity CH4 conversion factor Swine: 4.2 g head -1 day -1 Steers: 145 g head -1 day -1 Dairy cows: 351 g head -1 day -1 45
Estimating N 2 O emission using the IPCC approaches N excretion rate N 2 O emission factor Direct N 2 O emission 0.31-1.10 kg N (1000kg BW) -1 day -1 0.001-0.02 kg N 2 O-N/kg N 46
Questions on the IPCC approaches Whether the IPCC approaches adequately capture the variation which exists in animal operations? Researches suggest that the IPCC approaches overestimated GHG emissions (Marinier et al.,2004; Park et al., 2006; DeSutter and ham, 2006) The CH4 conversion factors used in the IPCC approaches are flawed (Lory et al., 2010) There is a clear need for more studies to assess the validity of the IPCC approaches, to provide the basis for revision of EFs and to make EFs more locally applicable 47
Meta-analysis of GHG from swine operation Compare the measured values of GHG emissions from swine operations in literature to the estimated values using the IPCC approaches. Identify and evaluate the causes of the variation in the reported GHG emissions Explore sources of heterogeneity in the studies and possible new hypotheses Provide recommendations on directions for future research 48
Factors affecting AFO emission Air emissions from AFOs depend on manure characteristics and how the manure is managed ph/temperature of manure Aerobic or anaerobic microbial environment Precursors present in the manure (N, S) Wet/dry manure management systems Emission Manure storage time 49
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 50
Emission models Statistical models N-mass flow models Process based models Can be useful in assessing the accuracy of mechanistic approaches. Mass balance approach Simulate the N flow over the different stages of emissions Mechanistic Consider each of the processes occurring on a typical farm 51
Outline I. What are emitted from farms? Background Gas species, impacts, regulations II. How much are emitted? Measurement technologies, emission factors, NAEMS study Carbon footprint, IPCC approaches and meta-analysis of GHG emissions Emission models III. Diet as a control strategy 52
Dietary strategies Reducing dietary crude protein (CP) Supplementing amino acids (AA) Providing an optimal balance of rumen degradable protein (RDP) and rumen undegradable protein (RUP) Influence of incorporation of distillers dried grains with solubles (DDGS) Influence of different ingredients that represent typical Western, Midwestern or Southeastern U.S. diets 53
Michigan State University Animal Air Quality Research Facility (AAQRF) 12 environmental rooms Each room: H 2.14 m W 3.97 m L 2.59 m 54
Animals and Housing Cow, heifer or Steer (1) Finishing pigs (6) Turkeys (20) Broiler chickens (50) Laying hens (56-80) 55 55
Air sampling and measurement system Incoming air Room1 Room2 Model 17C NH 3, NO, NO 2 Room3 Room4 Room5 Room6 Room7 Room8 Gas samples were sequentially monitored from each room and incoming air Sampling manifold Model 55C BINOS CH 4 CO 2 / O 2 Room9 Room10 Room11 INNOVA CO 2, CH 4, N 2 O, NMTHC, NH 3 Room12 56
Example of a turkey tom study 4 diets in a 2 2 factorial design 100 or 110% of NRC (1994) 2 or 3 supplemental AA. 100%NRC +2 AA 100%NRC +3AA Reduced feed N Each diet was fed to 3 rooms. 110%NRC +2AA 110%NRC +3AA 5 feeding phases (4 wks per phase). Reduced feed N Diet samples were analyzed by the University of Missouri Agriculture Experiment Station Laboratory. 57
Effect of diet on air emission rates Main effect means, g/day-bird P-value 100 % 110 % +2AA +3AA % of NRC # of AA NRC AA NH 3 1.5 a 1.8 b 1.8 b 1.4 a 0.03 <0.01 0.30 N 2 O 0.15 0.15 0.15 0.15 0.63 1.00 0.52 H 2 S 0.0034a 0.0044b 0.0038 0.0040 <0.01 0.42 0.65 NMTHC 0.08 a 0.10 b 0.09 0.09 0.04 0.42 0.09 CH 4 0.25 0.28 0.26 0.26 0.42 0.89 1.00 58
Diet effect on cumulative N intake and NH 3 emissions 100% NRC vs. 110% NRC +3AA vs. +2AA Reduced N intakes by 9% Reduced NH 3 by 12% Did not affect N intake Reduced NH 3 by 25% Reduced NH 3 emission rate on a per kg N consumption basis (88 vs. 109 g d 1 kg 1 N consumed) 59
N balance in the turkey tom study NH3-N emission N2O-N emission 1% 11% Input 100% Output 102.3% N in ending toms 32% N in excretion 58% 100% NRC vs. 110% NRC Higher N retention (33.8% vs. 30.9%) +3AA vs. +2AA Higher N retention (33.2% vs. 31.5%) Less NH 3 -N emission (9.9% vs. 12.4%) 60
Species and diets of the studies Broilers Laying hens Turkeys Finishing pigs Steers Heifers Dairy cows Reduced N vs. control 3*2 Reduced N and litter amendment PLT 0 and 15% DDGS 0,10%,20% DDGS 2*2 0, 20% DDGS organic or inorganic trace minerals With or without supplemental methionine 2*2 100%, 110% NRC 2, 3AA 0 and 20% DDGS 15% DDGS with or without microbial or chemical additive 0, 40%, 60% DDGS 0, 60% or 60% DDGs plus added copper and molybdenum Quillaja, yucca, or no extract Quillaja, yucca, or no extract High and low rumen degraded protein High and low rumen degraded protein Typical Western Midwestern or Southeastern U.S. diets Typical Western Midwestern or Southeastern U.S. diets 61
Diet effects on NH 3 emissions Broilers Laying hens Turkeys Finishing pigs Steers Heifers Dairy cows Reduced N vs. control 3*2 Reduced N and litter amendment PLT 0 and 15% DDGS 0,10%,20% DDGS 2*2 0, 20% DDGS organic or inorganic trace minerals With or without supplemental methionine 2*2 100%, 110% NRC 2, 3AA P<0.10 0 and 20% DDGS 15% DDGS with or without microbial or chemical additive 0, 40%, 60% DDGS 0, 60% or 60% DDGs plus added copper and molybdenum Quillaja, yucca, or no extract Quillaja, yucca, or no extract High and low rumen degraded protein High and low rumen degraded protein Typical Western Midwestern or Southeastern U.S. diets Typical Western Midwestern or Southeastern U.S. diets 62
Diet effects on CH 4 emissions Broilers Laying hens Turkeys Finishing pigs Steers Heifers Dairy cows Reduced N vs. control 3*2 Reduced N and litter amendment PLT 0 and 15% DDGS 0,10%,20% DDGS 2*2 0, 20% DDGS organic or inorganic trace minerals With or without supplemental methionine 2*2 100%, 110% NRC 2, 3AA P<0.10 0 and 20% DDGS 15% DDGS with or without microbial or chemical additive 0, 40%, 60% DDGS 0, 60% or 60% DDGs plus added copper and molybdenum Quillaja, yucca, or no extract Quillaja, yucca, or no extract High and low rumen degraded protein High and low rumen degraded protein Typical Western Midwestern or Southeastern U.S. diets Typical Western Midwestern or Southeastern U.S. diets 63
GHG emission (g kgbw -1 day -1 in CO2-eq) GHG emissions in CO 2 -eq 40 35 30 25 N2O CH4 20 15 10 5 0 broiler Laying hen Turkey Finishing pig Steer Heifer Dairy cow 64
Oil sprinkling and acidification Sprinkling oil or oilwater mixture has been successfully used to reduce dust (20-90%) in animal houses (Takai, 2007; Zhang et al., 1996) Not as definitive in reducing NH 3 Reduce both dust and NH 3 by sprinkling a small amount of oil-acid mixture on a daily basis Acidification of litter prior to bird placement has been used to reduce NH 3 emissions in poultry houses (Shah et al., 2006) Effectiveness is lost in 3 weeks after initial application. 65
Composting as a GHG mitigation practice The primary GHG credits Avoided GHG emissions from landfilled, incinerated or openly-stored waste GHG credits and debits at different stages of composting Upstream indirect emissions from energy used in composting. Direct emissions during composting. Downstream avoided emissions resulted from end use of the compost by substituting fertilizer or binding of C in the soil. 66
Mortality composting Comparison of GHG emissions from OSP and IV composting systems during primary phase (first 20 days) Composting system GHG emission rates (g CO 2 -eq kg -1 carcass day -1 ) In-vessel Open static pile CH 4 0.018 11.609 N 2 O 0.000 4.355 (Rozeboom et al., 2011) 67
Michigan Odor from Feedlots Setback Estimation Tool (OFFSET) Calculates a unique odor footprint for each livestock production site based on inputs (species, housing type and size, type and size of manure storage structure) The lines here represent the distances that one must be away from the odor source to detect a noticable odor or stronger up to 1.5%, 3% and 5% of the time for each of the 16 wind directions. 68
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