Quantifying Emissions of Ammonia For Air Quality Analysis

Transcription

1 Quantifying Emissions of Ammonia For Air Quality Analysis Viney P. Aneja Department of Marine, Earth, and Atmospheric Sciences North Carolina State University Raleigh, NC , U.S.A Science Meeting "Total Reactive Nitrogen: Regional Haze Impacts and Mitigation Options July 28-29, 2009 Baltimore, MD

2 U.S. Agricultural 2008 Preliminary Revenues Confined Animal Feeding Operations (CAFOs) Livestock receipts: ~$143.1 billion Crop receipts: ~$181.1 billion Source:

3 National Media Attention July 12, 2004 July 7, 2004 June 3, 2004

4 Emission, Transport, Transformation, and Deposition of Trace Gases Source: Aneja et al., 2006, Eos

5 National Research Council, 2002 Report The Scientific Basis for Estimating Emissions from Animal Feeding Operations The stakes in this issue are large. More and more livestock are raised for at least part of their lives in AFO s in response to economic factors that encourage further concentration. The impacts on the air in surrounding areas have grown to a point where further actions to mitigate them appear likely. EPA may use information from this project in determining how it will approach regulating both air and water quality impacts of AFOs. Substantial emissions of nitrogen (N), sulfate (S), carbon (C), particulate matter (PM), and other substances from AFOs do occur and cannot be ignored.

6 Impacts of Enhanced Ammonia on the Environment Particulate matter (PM) formation Visibility degradation Nitrogen enrichment and eutrophication in aquatic ecosystems Impact on crop and forest production Impact on ground water quality Impact on biodiversity Odors and odorants Changes in rainfall chemistry

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8 Gas-To To-Particle Conversion Processes Gas-phase Products H 2 O 2 HO 2 NO HO 2 Secondary Organic Aerosol CO, RH, RCHO H 2 SO 4 Aerosol Phase (Dp < 10um) OH SO 2 O 3 hv RCO 3 NO 2 3 PAN NO 3 NO 3 NH 3 N 2 O 5 H 2 O HNO3 NH 3 Droplet Phase (Dp > 10um) Chemical coupling in the atmospheric gas, particle, and droplet phases (Meng, et al., 1997).

9 U.S. Air Pollutant Emission Estimates (million tons/yr) CO NOx PM 2.5 PM 10 SO 2 VOC Pb NH (1990) Percent Change -55% -29% -13% -84% -52% -53% -99% +27% Source:

10 U.S. and Europe Air Pollutant Emission Estimates (million tons/yr) CO NOx PM 2.5 PM 10 SO 2 VOC Pb NH (1990) Percent Change -55% -29% -13% -84% -52% -53% -99% +27% Percent Change (Europe) -34% -76% -43% -22% Source:

11 Nonattainment Areas in 2005 Areas exceeding O 3 Standard Areas exceeding PM 2.5 Standard (Source: EPA Green Book, 2005) (PM 2.5 : Particulate Matter with an aerodynamic diameter of up to 2.5 µm )

12 Methods to Quantify Ammonia Emissions Emission factors Emission based on inverse modeling Process based modeling Remote sensing

13 Commercial Hog Farm in North Carolina, US Sampling Sites

14 Major Routes for N, S, and C Emissions from Intensively Managed Animal Operations in the USA Forage/Feed N, S, C Production Houses Urine/feces e.g.nh 3 Volatilization Waste Storage and Treatment Systems Urine/feces e.g.nh 3 Volatilization Land Application (i.e. spraying) Urine/feces e.g.nh 3 Volatilization Biogenic Emissions From Soil and Crops Urine/feces e.g.nh 3 Volatilization

15 Ammonia Flux Micrometeorological Experiment

16 Dynamic Flow-Through Chamber System

17 Source: Aneja et al., 2000, JGR

18 (Program OPEN) Log U.S. EPA WATER9 Model Program OPEN Ammonia Flux Measurements

19 Estimating Agricultural NH 3 Emissions (Emission Factor Approach) Emission Rate (kg NH 3 year -1 ) = Activity Data (animal population) * Emission Factor (kg NH 3 animal -1 year -1 ) Activity Data: U.S. Census of Agriculture for 2002 at county-level Beef and Dairy Cattle Hogs and Pigs Chickens Broilers Turkeys Horses Sheep Fertilizer Application (AAPFCO)

20 Volcanic emissions?

21 Primary Sources of Ammonia Emissions for Animal Agriculture by Region Based on current emission factor approach.

22 U.S. Ammonia Emission Factors for Animal and Crop Agriculture Animal Agriculture Emission factor (kg-nh 3 /animal/ yr) Animal Battye, Aneja, & Roelle, U.S. EPA: Battye et al., Dairy cow Beef cow (steers) Sow Finishing pig Laying hen Broiler Sheep Horses Crop Agriculture Emission factor (kg NH 3 /Mg N) Fertilizer Aneja et al., U.S. EPA: Battye et al., N-P-K Nitrogen solutions Ammonium phosphates Anhydrous NH Urea Ammonium nitrate Other straight nitrogen Ammonium sulfate Aqua NH Ammonium thiosulfate 30 30

23 U.S. Ammonia Emission Estimates (2002) Non Agriculture 20.4% Dairy Cattle 11.9% Beef Cattle 14.0% Fertilizer 27.9% Poultry 14.2% Horses 1.5% Goats 0.3% Sheep 0.5% Swine 9.2% Total emissions: ~4 million tons/yr Source: U.S. EPA 2002 National Emissions Inventory

24 2002 Ammonia Emissions Source: U.S. EPA, 2007 Based on current emission factor approach.

25 Ammonia Concentration CMAQ Output 36km grid 2001 emissions inventory and meteorology SAPRAC chemistry module Concentrations range from 0-12 ppb Provides an idea of representativeness of sample locations Source: U.S. EPA, 2007

26 Seasonal NH 3 Emissions: Inverse Model Estimation Comparison of model (CMAQ) and measured NH 4+ wet deposition Source: Gilliland et al., Atmos. Environ., 2006

27 CMAQ Ammonium Ion Wet Deposition NADP Ammonium Ion Wet Deposition CMAQ is able to capture main spatial pattern and magnitude of wet deposition Courtesy: R. Dennis/R. Mathur (EPA)

28 Commercial Hog Farm in North Carolina, US Sampling Sites

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33 Measurements Compared with NH 3 MTCR Model NH 3 flux from a swine waste lagoon system: Fall 2004 NH3 -N F lux (μ g m -2 min -1 ) October 31, :00 6:00 12:00 18:00 0:00 Time of Day Observed Modeled Measured NH3 Flux R 2 = MTCR Modeled NH 3 Flux

34 Satellite Remote Sensing for Ammonia and Particulate Matter

35 Ammonia Emission Projections 1, NH 3 Emissions (thousand tons/yr) Beef Cattle Dairy Cattle Poultry Swine Year Source: U.S. EPA, 2007 Based on current emission factor approach.

36 Cattle Addition of Alum or Zeolite to slurry to stop volatilization Alum Reduction 2.5% 58 ± 6% 6.25% 57 ± 10% Zeolite Reduction 2.5% 22 ± 6% 6.25% 47 ± 10% Acidifying liquid cow manure with lactic or nitric acid Nitric Acid ph Lowered emissions by Lactic Acid ph Lowered emissions by % % % % %

37 Swine Manure additives 24% reduction Biotrickling filters (Hansen, 2006) Reduce odor Winter 54% Summer 28% Reduce ammonia Storage spreading system with biological treatment of manure (Loyon, 2006) Reduced NH % with separated manure 68% with unseparated manure

38 The Process Solid-liquid Separation Module Nitrification Denitrification Module Phosphorus Removal Module Effluent Reuse Separated Solids Calcium Phosphate Super Soil Systems North Carolina s Swine Waste Treatment Solution

39 Summary and Conclusions Emission factors approach Easy to use, but results may have uncertainty Process based and inverse modeling approach Complex but results have less uncertainty Remote sensing approach Emerging area of gaseous and PM emission analysis

40 Challenges for the Community What are the potential health effects from exposures to ambient levels of NH 3? How does NH 3 react in the presence of other prevalent air pollutants such as SO 2, NO X, etc.? What are the sources of excess NH 3 in the atmosphere? What is excess? How much is natural? What do we know about reactions in the atmosphere? Is there long range atmospheric transport? Are current air monitoring methods sufficient for NH 3 measurement? Vertical bi-directional transport of ammonia?

41 Challenges for the Community Are current air quality modeling techniques sufficient for analyzing the N cycle, including NH 3? Is it prudent to regulate NH 3 and NO X or should we focus on the total N cycle? How do we optimize and evaluate the impacts of reductions of the various forms of N and of other air pollutants? Are control technologies for agricultural sources available? Are they feasible? What are the proven methods (BMPs) and their associated costs for reducing NH 3 from agricultural sources? Need for a network to monitor emissions from agricultural sources.

42 U.S. Department Of Agriculture National Research Initiative, Contract No Phosphate Potash Institute, The Fertilizer Institute The National Science Foundation The Kenan Institute North Carolina Division of Air Quality, Contract No. EA 01001, and EA 8001 Animal and Poultry Waste Management Center / Smithfield Foods Water Resource Research Institiute, Contract No. EA 7003 Ms. Megan Gore Acknowledgements

43 Quantifying Emissions of Ammonia For Air Quality Analysis Viney P. Aneja Department of Marine, Earth, and Atmospheric Sciences North Carolina State University Raleigh, NC , U.S.A Science Meeting "Total Reactive Nitrogen: Regional Haze Impacts and Mitigation Options July 28-29, 2009 Baltimore, MD

44 National Hog Farming Trends Changes in Production Facilities Hog Population 58.2 million 61.3 million Number of Hogs (Millions) States with most hogs Year Animals in Facilities > 2000 Head 29% 79% Iowa North Carolina Minnesota Illinois

45 Annual Average NH 3 Emissions (2001) US EPA Emission Factor Based Inventory