Steven J. Hoff

Ammonia and PM Emissions from a Tom Turkey Barn in Iowa

Considerable progress has been made toward collection of baseline data on air emissions from U.S. animal feeding operations. However, limited data exist in the literature regarding turkey air emissions. The project described in this paper continuously monitors ammonia (NH3) and particulate matter (PM) emissions from turkey production houses in Iowa (IA) and Minnesota (MN) for one year, with IA monitoring Hybrid tom turkeys and MN monitoring Hybrid hens. Mobile Air Emission Monitoring Units are used in the continuous monitoring. Data collection and analysis has been ongoing since May 2, 2007 for the IA site and October 9, 2007 for the MN site. Based on the one-year measurement at the IA site involving three flocks, daily NH3 emissions (g/d-bird) from the IA turkey house varied from 0.04 to 6.4 (mean of 1.9) for flock 1 (May-Aug), 0.2 to 3.4 (mean of 1.3) for flock 2 (Aug-Dec), and 0.16 to 3.8 (mean 1.4) for flock 3 (Dec-Apr). The PM10 emissions (g/d-bird) were 0.04 to 1.6 (mean of 0.58), 0.04 to 0.39 (mean of 0.2), and 0.04 to 0.82 (mean of 0.37) for flocks 1, 2, and 3, respectively; and the concomitant PM2.5 emissions (g/d-bird) were 0 to 0.11 (mean of 0.048), 0 to 0.05 (mean of 0.021), and 0 to 0.14 (mean of 0.053) for flocks 1, 2, and 3, respectively. Annual mean emissions from the tom turkeys (including downtime emission), expressed as grams of constituent per bird marketed, were 169 g NH3, 40 g PM10, and 4.3 g PM2.5 per bird marketed. Data collection and analysis at the MN site are ongoing.

Air Emissions from Tom and Hen Turkey Houses in the U.S. Midwest

Limited data exist in the literature regarding air emissions from U.S. turkey feeding operations. The project described in this article continuously monitored ammonia (NH3) and particulate matter (PM) emissions from turkey production houses in Iowa (IA) and Minnesota (MN) for 10 to 16 months, with IA monitoring Hybrid tom turkeys (35 to 143 d of age, average market body weight of 17.9 kg) for 16 months and MN monitoring Hybrid hens (35 to 84 d of age, average market body weight of 6.7 kg) for 10 months. Mobile air emission monitoring units (MAEMUs) were used in the continuous monitoring. Based on the approximately one-year measurement, each involving three flocks of birds, daily NH3, PM10, and PM2.5 concentrations (mean ±SD) in the tom turkey barn were 8.6 ±10.0 ppm, 1104 ±719 µg m-3, and 143 (±124) µg m-3, respectively. Daily NH3 and PM10 concentrations (mean ±SD) in the hen turkey barn were 7.3 ±7.9 ppm and 301 ±160 µg m-3, respectively. Daily NH3 concentrations during downtime (mean ±SD) were 38.4 ±20.5 and 20.0 ±16.3 ppm in the tom and hen barns, respectively. The cumulative NH3 emissions (mean ±SE) were 141 ±13.1 and 1.8 ±0.9 g bird-1 for the tom turkeys during 108 d growout and 13 d downtime, respectively, and 52 ±2.1 and 28.2 ±2.5 g bird-1 for the hen turkeys during 49 d growout and 32 d downtime, respectively (the extended downtime for the hen house was to ensure monitoring of one flock per season). The cumulative PM10 emission (mean ±SE) was 28.2 ±3.3 g bird-1 for the tom turkeys during 108 d growout and 4.6 ±2.2 and 0.3 ±0.06 g bird-1 for the hen turkeys during 49 d growout and 32 d downtime, respectively. Downtime in the hen house was of greater duration than would be typically observed (32 d vs. 7 d to 14 d typical). The cumulative PM2.5 emission (mean ±SE) was 3.6 ±0.7 g bird-1 for the tom turkeys during 108 d growout (not monitored for the hen turkeys). Because farm operations will vary in flock number, growout days, and downtime; annual emissions can be calculated from the cumulative emissions and downtime emissions per bird from the data provided. Air emissions data from this study, presented in both daily emission and cumulative per-bird-marketed emission, contribute to the improved U.S. national air emissions inventory for animal feeding operations.

Real-Time Ventilation Measurements from Mechanically Ventilated Livestock Buildings for Emission Rate Estimations

A six-state USDA-IFAFS funded research project (Aerial Pollutant Emissions from Confined Animal Buildings, APECAB) was conducted with the purpose of determining hydrogen sulfide, ammonia, PM10, and odor emission rates from selected swine and poultry housing systems. An important aspect of emission studies is to be able to measure the mass flow rate of air through the housing system. For this research project, the decision was made to study only fan ventilated buildings due to the difficulty in estimated mass flow rates through naturally ventilated buildings. This paper highlights the various techniques used throughout the study to determine mass flow rate through fan ventilated swine and poultry housing systems.

Effects of Bird Activity, Ventilation Rate and Humidity on PM10 Concentration and Emission Rate of a Turkey Barn

Concentrations and emissions of particulate matter with aerodynamic diameters = 10 µm (PM10) were continuously measured in a mechanically ventilated turkey grow-out barn in central Iowa. The PM concentrations were measured with Tapered Element Oscillating Microbalance (TEOM) units; and ventilation rate (VR) of the barn was measured by monitoring the runtime of calibrated ventilation fans. Bird activity (BA) was monitored with passive infrared detectors (PIDs). This paper describes the effects of BA, VR and indoor relative humidity (RH) on the PM concentration and emission rate (ER) based on 18 days of full 24-hr dynamic data collected during 67 days of flock-growing period (bird age of 40 - 107 d) in wintertime. Considerable diurnal variations were observed in BA, PM concentration and PM ER of the turkey barn. The PM concentration and ER were positively related to BA but negatively related to indoor RH. VR was negatively related to PM concentration but positively related to ER. The PM10 ER during the monitoring period varied from 2.71 to 25.6 mg/hr·bird or 13.4 to 28.8 g/d·AU (AU = 500 kg body mass).

Use of CO2 Concentrations or CO2 Balance to Estimate Ventilation Rate of Modern Commercial Broiler Houses

Ventilation rate (VR) is one of the two key elements for quantifying aerial emissions from nanimal production facilities. Direct measurement of building VR can be challenging and impractical nunder certain circumstances, e.g., naturally ventilated animal housing. This study delineates VR of nbroiler houses with build-up litter as estimated via CO2 balance or building CO2 concentration. The nindirectly derived VR compared favorably with the directly measured VR. Specifically, integration ntime of 30 min or longer leads to non-significant differences in VR between the indirect and the direct nmethods (P>0.2). Omission of CO2 generation by the litter from total house CO2 production results in nan overall 7% underestimation of the building VR. The indirect method provides a possible, viable nalternative for quantifying VR of naturally ventilated broiler confinement.

Monte Carlo Technique for the Determination of Thermal Radiation Shape Factors

ABSTRACT The principles and equations of the Monte Carlo technique are outlined for determining thermal radiation shape factors. Equations for the ray tracings and intersection criteria needed to calculate the shape factors between plane walls, cylinders and spheres are presented. The equations presented and resulting shape factors are demonstrated with selected geometric configurations for which the shape factors are known. Computer results using the Monte Carlo technique of six geometric arrangements produced results within 2.2% of theoretically known shape factors.

Odor and odorous chemical emissions from animal buildings: Part 2- odor emissions

This study was an add-on project to the National Air Emissions Monitoring Study (NAEMS) and focused on comprehensive measurement of odor emissions. Odor emissions from two animal species (dairy and swine) from four sites with nine barns/rooms (two dairy barns in Wisconsin, two dairy barns and two swine rooms in Indiana, and three swine barns in Iowa) during four cycles (13-week periods) were measured. Odor samples were analyzed in three olfactometry laboratories and no significant difference was found among these laboratories. The highest ambient odor concentrations and barn odor emissions were measured for the Iowa swine site. The most intense odor and the least pleasant odor were also measured for this site. Ambient odor concentrations were the lowest for the Wisconsin dairy site. But the lowest barn odor emission rates were measured for the Indiana dairy site. Significantly higher odor emissions were measured in summer.

Air Pollutant Emissions from Confined Animal Buildings (APECAB) Project Summary

To address the need for gas, odor, and particulate matter (PM) emission from animal production buildings, funding was secured in the fall of 2001 by a six-state research team for a USDA project entitled “Air Pollutants Emissions from Confined Animal Buildings,” or APECAB. The main objective of the APECAB project was to quantify long-term (yearly) air pollutant emissions from confined animal buildings and establish methodologies for real time measurement of these emissions and build a database of air emissions for US livestock and poultry buildings.

Odor and odorous chemical emissions from animal buildings: Part 4- correlations between sensory and chemical measurements

This study supplemented the National Air Emissions Monitoring Study (NAEMS) by making comprehensive measurements, over a full calendar year, of odor emissions from five swine and four dairy rooms/buildings (subset of the total number of buildings monitored for the NAEMS project). The measurements made in this project included both standard human sensory measurements using dynamic forced-choice olfactometer and a novel chemical analysis technique for odorous compounds found in these emissions. Odor and hydrogen sulfide (H2S) and ammonia (NH3) concentrations for all dairy and swine buildings had a statistically significant correlation. A higher number of correlations between odor and volatile organic compounds (VOCs) were found for the five swine rooms/buildings (two rooms in a pig finishing barn, two sow gestation barns, and a farrowing room) compared to the four dairy buildings. Phenol and 4-methyl phenol (p-cresol) concentrations were well correlated (R2 > 50%) with odor concentrations in the five swine rooms/buildings but not significantly correlated in the four dairy buildings.

Can Mass Balance Be Trusted in Estimating N Loss for Meat-Poultry Housing?

Quantification of ammonia loss from animal feeding operations by measuring gaseous concentration and air exchange through the emitting source is not always practical, e.g., under natural ventilation conditions. Mass balance over an extended period of time may offer possibilities of remedy. This study compares two NH3-N emission estimate approaches for a commercial turkey grow-out house over one year period: a) a concentration-flow-integration (CFI) method (considered as the reference method), and b) a nitrogen (N) mass-balance method. The CFI NH3-N emission was determined by continuously measuring the NH3 concentration and exhaust air flow rate through the turkey house with a state-of-the-art mobile air emission unit. The mass-balance N emission was calculated by balancing the total N inputs (new bedding, young birds, feed) and N output (litter cake removed between flocks, litter removed at cleanout, amount of marketed birds, mortality, and body N content). The production-related data were acquired from the records kept or presented to the cooperative producer. The results revealed unexpectedly large discrepancy in NH3-N loss between the two methods. The outcome of this study cast serious doubt about the adequacy of using mass balance for estimating NH3 emissions from a dynamic production system such as turkey houses.