Emission Measurements and Comparison with Management Techniques for Beef Deep- Bedded Mono-Slope Facilities. Objectives of the Presentation

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1 Emission Measurements and Comparison with Management Techniques for Beef Deep- Bedded Mono-Slope Facilities Erin Cortus Mindy Spiehs LPELC Webinar July 19, 213 Objectives of the Presentation Project origins Project overview Particulate matter concentration Gas concentrations Air flow and gas emissions Deep-Bedded Mono-Slope Barns East-west orientation with southern exposure Natural ventilation Curtain-sided Stocking density: 38-5 sq ft/animal May allow a bedpack to accumulate in center of pen or may scrape and haul on a weekly basis Area around pack scraped and bedded 1-2 times/week Bedded with corn stalks or bean stubble 1

2 This started March, 27 with a USDA MARC visit to NW IA ISU/MARC Mono-Slope Barn Research 1 ft wide barns Two pens per barn March 28 October 29 Sampled every 5-7 weeks Goals of the Research To determine spatial and seasonal effects on ammonia concentrations from the pen surface This data did not represent absolute emissions from the barn! Spiehs et al., 211 Trans ASABE 54:

3 Grant Advisory Committee Air Quality Concerns Related to Regulations Ammonia Particulate Matter Related to Cattle Production Time of Day Seasonal Effects Are they are doing it right? Emission Measurements and Comparison with Management Techniques for Beef Deep-Bedded Mono-Slope Facilities Project funded by Agriculture and Food Research Initiative Competitive Grant no from the USDA National Institute of Food and Agriculture. 3

4 South Dakota State University USDA-ARS Meat Animal Research Center The Team Iowa State University Extension and Outreach Livestock and Poultry Environmental Learning Center Purpose of Air Quality Grant Gather baseline emission data from beef confinement barns Evaluate 2 manure handling systems Weekly Scrape and Haul South Dakota Sites Bedpack Iowa Sites SD Site Characteristics Characteristic SD1 (2 pens) SD2 (2 pens) Pen Dimensions (m) x x Pen Capacity (hd) 3 3 Is there a wall bordering any Pens? Yes, both Pens No South Wall Height (m) Feed Bunk Height (m) South Wall Opening Area per Pen (m 2 ) 7.17*41.15 = *36.58 = North Wall Min Opening Height with Curtains(m)..25 North Wall Max Opening Height with 2.29m before 8/23/211, 2.3m 2.44 Curtains (m) after 8/23/211 North Wall Opening Height without Curtains (m) Number of Curtains 3 1 curtain before 8/23/211, 2 curtains after 8/23/211 Topography (N) Mono-slope barn Field Topography (S) Pasture Grass with bale storage 4

5 IA Site Characteristics Characteristic IA1 (1 pen) IA2 (2 pens) Pen Dimensions (m) x x26.82 Pen Capacity (hd) Is there a wall bordering any Pens? yes one pen yes both pens South Wall Height (m) Feed Bunk Height (m) South Wall Opening Area per Pen (m 2 ) 7.89*73.15= *27.43= North Wall Min Opening Height with Curtains(m) North Wall Max Opening Height with Curtains (m) North Wall Opening Height without Curtains na/ rolled curtains are fixed in na/ rolled curtains are fixed in (m) place place Number of Curtains 2 2 Topography (N) Corn field Corn field Topography (S) Corn field Corn field Monitoring Weather On-site weather station measured Wind direction Wind speed Ambient air temperature Relative humidity Monitoring Air Quality in Barns Two barns in SD and IA Instrument trailers were rotated between the barns Sampling locations on the north and south side of the barn measured Ammonia Hydrogen sulfide Methane Carbon dioxide Nitrous oxide Particulate matter was monitored periodically 5

6 Collecting the Data All wiring and tubing ran to the instrument trailer Instruments in the trailer measured the gases A computer recorded the gas measurements and weather data Monitoring Particulate Matter South Dakota Sites Measured using Minivols Collected baseline emission data Iowa Site Measured using Lo-Vol Particulate Air Samplers Evaluated concentration relative to management events Part 1: Particulate Matter Adjacent to Cattle Deep- Bedded Mono-slope Facilities 6

7 Objective Compare particulate matter concentration adjacent to a deep-bedded mono-slope facility during normal operation and a bedding event. Sampling Procedure Lo-Vol Particulate Samplers Three placed 4.6 m (15 ft) from the north side of the building Three placed 4.6 m (15 ft) from the south side of the building 36.6 m (12 ft) between the samplers on each side Average sampler flow rate was 16.7 L/min

8 Sampling Procedure Each sampler contained pre-weighed filters Samples were collected over two five-day periods April 28 May 5, 211 June 24 July 1, 211 Each sample period included three 24-hr collections during normal operation and two 3-hr collections during a bedding event Filters collected and sent to USDA ARS Cotton Production and Processing Research Unit, Lubbock, TX to determine total suspended particles (TSP). Results 14 Total Suspended Particles April 28 - May 5, Concentration (µg/m 3 ) Bedding Event Prevailing South wind Bedding Event Prevailing North wind North 1 North 2 North 3 South 1 South 2 South 3 2 4/27/211 4/28/211 4/29/211 4/3/211 5/1/211 5/2/211 5/3/211 5/4/211 5/5/211 5/6/211 Date 8

9 6 Total Suspended Particles June 23 - July 2, Bedding Event Wind changed direction during sampling Concentration (µg/m 3 ) North 1 North 2 North 3 South 1 South 2 South 3 Bedding Event Slight south wind 1 6/23/211 6/24/211 6/25/211 6/26/211 6/27/211 6/28/211 6/29/211 6/3/211 7/1/211 7/2/211 Date Average Concentrations Average 24-hr TSP concentration on days of normal operation was 58.6 ± 3.9 µg/m 3 Average 3-hr particulate matter concentration during a bedding event was 72.2 ± µg/m 3 TSP significantly higher during bedding events compared to normal operations (P =.4) Part 1: Conclusions In general, particulate matter concentrations adjacent to the deep-bedded mono-slope facility were lower than previously reported for open lot feedlots. Concentrations of TSP were higher during the 3-hr bedding event than during normal operation but quickly return to baseline levels following bedding event. 9

10 Part 2: Gas Concentrations in Mono-slope Facilities Objective: Describe changes in ammonia, hydrogen sulfide and methane concentrations in the barn based on temperature and time of day South Dakota Sites Daily Mean Temperatures Temperature, C SD1 Ambient SD1 Barn SD2 Ambient SD2 Barn /6/1 1/22/11 8/1/11 2/26/12 Iowa Sites Daily Mean Temperatures Temperature, C IA1 Ambient IA1 Barn IA2 Ambient IA2 Barn /17/1 4/5/11 1/22/11 5/9/12 1

11 Concentration, ppb Average Hourly Mean Hydrogen Sulfide Concentration (ppb) as Influenced by Temperature Temperature ±2.5, C Concentration, ppb Average Hourly Mean Ammonia Concentration (ppb) as Influenced by Temperature Temperature ±2.5, C Average Hourly Mean Methane Concentration (ppb) as Influenced by Temperature 12 1 Concentration, ppb Temperature ±2.5, C 11

12 Average Hourly Mean Hydrogen Sulfide Concentration (ppb) as influenced by Time of Day 25 Concentration, ppb Hour of the Day Average Hourly Mean Ammonia Concentration (ppb) as influenced by Time of Day 6, 5, Concentration, ppb 4, 3, 2, 1, Hour of the Day Average Hourly Mean Methane Concentration (ppb) as influenced by Time of Day Concentration, ppb 14, 12, 1, 8, 6, 4, 2, Hour of the Day 12

13 Average Concentrations (ppb) Hydrogen Sulfide Ammonia 2,1 2,4 2,2 4,3 Methane 9,2 7,9 5,2 8, Part 2: Conclusions Gas concentrations below workplace thresholds Temperature impact is most pronounced for hydrogen sulfide concentrations in bedded pack barns Daily variation can be related to animal activity Manure management system effect differed between gases Part 3: Airflow and Gas Emissions from Mono-slope Facilities Objective: Measure the airflow through and the gas emissions from monoslope facilities 13

14 Airflow Assumptions South Wall Opening Airflow = Perpendicular Velocity x Area North Wall Opening Airflow = Perpendicular Velocity x Area Assuming constant air density: South Wall Opening Airflow = North Wall Opening Airflow Example Data for One Site Combined Pen 1 and Pen 2 Airflow Through Opening to the North, m3/s Northerly Airflow North South -1 Southerly North Airflow Wind South Wind Weather Tower Wind Speed Perpendicular and Into South Wall Opening, m/s Example Data for One Site Closed Curtain (< 1.5 m) Open Curtain (>1.5 m) North South North South Combined Pen 1 and Pen 2 Airflow Through Opening to the North, m3/s Weather Tower Wind Speed Perpendicular and Into South Wall Opening, m/s Combined Pen 1 and Pen 2 Airflow Through Opening to the North, m3/s Weather Tower Wind Speed Perpendicular and Into South Wall Opening, m/s 14

15 Relationships Between Airflow Through North and South Walls (South Wind) Combined Pen 1 and Pen 2 Airflow Through North Wall, m 3 /s 12 1 Scrape B y =.81x R² = Scrape A y =.4893x R² = Pack B y =.8974x R² = Pack A 2 y =.5656x R² = Combined Pen 1 and Pen 2 Airflow Through South Wall, m 3 /s Airflow, m3/s Airflow Direction and Concentration 6 4 Airflow Out of the South Wall Ammonia Concentration, ppb Ammonia Concentration at the South Wall (Green) and North Wall (Red) : 2:24 4:48 7:12 9:36 12: 14:24 16:48 19:12 21:36 : Average Emission Rates Method Emission = Airflow x Concentration Difference Airflow data conditions Open curtain South wind Daily means reported when > 75% of the day s data meets airflow conditions Results Less reportable emission data Variable airflow conditions Relationships with temperature are not as clear Reported emission data are biased high Open curtain conditions during warmer weather 15

16 Hydrogen Sulfide Emissions (g/d-head) Average Range Number of Daily Means Ammonia Emissions (g/d-head) Average Range Number of Daily Means Methane Emissions (g/d-head) Average Range Number of Daily Means

17 Part 3: Conclusions Strong relationships between north and south wall airflow for south wind and open curtain conditions Conditions for accurate airflow measurements limit emission data Large range in emission measurements because of variable airflow in addition to temperature and manure conditions Key Points Manure and bedding management impact gas and particulate matter concentrations and emissions Temperature and animal activity impact gas concentrations Range and variability in management practices and resulting emission data support continued investigation into process-based models Thank You! 17