7 research outputs found
A Process-Based Ammonia Emission Model for Confinement Animal Feeding Operations—Model Development
A process-based modeling approach was used to develop a comprehensive and predictive ammonia emission model for estimating ammonia emission rates from animal feeding operations. The ammonia emission model consists of farm emission model (FEM) and animal allocation processor (AAP) and can be used to calculate ammonia emission rates both from an individual AFO and from a group of AFOs and also allows predictions of different time scale resolutions. The Farm Emission Model (FEM) covers five animal species, including dairy, beef cattle, swine, layers, broilers, and turkeys. For each species, the FEM reflects different farm practices with regards to animal feeding, animal housing, manure collection and storage, and land application. The overall structure and selected model components of FEM are described in this paper. Some computer simulation results for a finishing swine farm are presented. The predicted ammonia emission rates are variable during the day and over the period of the year
An Improved Process Based Ammonia Emission Model for Agricultural Sources—Emission Estimates
Ammonia is an important atmospheric pollutant that combines with sulfuric acid and nitric acid to form aerosol sulfates and nitrate, respectively. These aerosol species are major components of fine particulate matter (PM) and contribute significantly to visibility impairment. Estimates of ammonia emission factors are both highly variable and uncertain. Emissions factors vary depending on meteorological conditions and seasonal and regional differences in farming practices. Previous ammonia emissions inventories have not adequately characterized seasonal and geographical variations in emissions factors. Recent chemical transport modeling suggests that daily and hourly variability in ammonia emissions is required to model accurately the formation of ammonium nitrate and ammonium sulfates.
In a companion paper, the development of a process-based model for predicting or estimating ammonia emission rates and factors from individual or a group of animal feeding operations at local, regional and national levels was presented. This paper discusses the data requirements and implementation of the process-based ammonia emission model. Preliminary emission estimates developed from the process-based ammonia emission model are also presented. Detailed description of databases used as input values for the process-developed model and recommendations for future improvement on the farm-based data regarding the animal feeding and manure management practices are documented. Where available, comparisons of the new ammonia emission estimates with existing ammonia emission inventories for livestock farms at a local, regional and national level are presented.
The work presented here is sponsored and funded by the Lake Michigan Air Directors Consortium (LADCO)
Hydrogen Sulfide Emission and Control Parameters From Stored Liquid Swine Manure
130 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997.Providing anoxic conditions by adding nitrates was observed to reduce H\sb2S production from liquid swine manure. Nitrates were quickly depleted in the first two days of manure storage. The presence of nitrate was observed to reduce H\sb2S concentration in the manure quite significantly. However, sulfides were not removed completely from the liquid manure once it was formed despite adding nitrates. Also, continuous application of nitrates may result in nitrate accumulation in the manure.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD
Integrating Climate Forecasts with the Soil and Water Assessment Tool (SWAT) for High-Resolution Hydrologic Simulations and Forecasts in the Southeastern U.S.
This study provides high-resolution modeling of daily water budget components at Hydrologic Unit Code (HUC)-12 resolution for 50 watersheds of the South Atlantic Gulf (SAG) region in the southeastern U.S. (SEUS) by implementing the Soil and Water Assessment Tool (SWAT) model in the form of a near real-time, semi-automated framework. A near real-time hydrologic simulation framework is implemented with a lead time of nine months (March–December 2017) by integrating the calibrated SWAT model with National Centers for Environmental Prediction coupled forecast system model version 2 (CFSv2) weather data to forecast daily water balance components. The modeling exercise is conducted as a precursor for various future hydrologic studies (retrospective or forecasting) for the region by providing a calibrated hydrological dataset at high spatial (HUC-12) and temporal (1-day) resolution. The models are calibrated (January 2003–December 2010) and validated (January 2011–December 2013) for each watershed using the observed streamflow data from 50 United States Geological Survey (USGS) gauging stations. The water balance analysis for the region shows that the implemented models satisfactorily represent the hydrology of the region across different sub-regions (Appalachian highlands, plains, and coastal wetlands) and seasons. While CFSv2-driven SWAT models are able to provide reasonable performance in near real-time and can be used for decision making in the region, caution is advised for using model outputs as the streamflow forecasts display significant deviation from observed streamflow for all watersheds for lead times greater than a month
A Process-Based Ammonia Emission Model for Confinement Animal Feeding Operations—Model Development
A process-based modeling approach was used to develop a comprehensive and predictive ammonia emission model for estimating ammonia emission rates from animal feeding operations. The ammonia emission model consists of farm emission model (FEM) and animal allocation processor (AAP) and can be used to calculate ammonia emission rates both from an individual AFO and from a group of AFOs and also allows predictions of different time scale resolutions. The Farm Emission Model (FEM) covers five animal species, including dairy, beef cattle, swine, layers, broilers, and turkeys. For each species, the FEM reflects different farm practices with regards to animal feeding, animal housing, manure collection and storage, and land application. The overall structure and selected model components of FEM are described in this paper. Some computer simulation results for a finishing swine farm are presented. The predicted ammonia emission rates are variable during the day and over the period of the year.This paper was presented at 14th International Emission Inventory Conference, 11–14 April 2005, Las Vegas, NV.</p
An Improved Process Based Ammonia Emission Model for Agricultural Sources—Emission Estimates
Ammonia is an important atmospheric pollutant that combines with sulfuric acid and nitric acid to form aerosol sulfates and nitrate, respectively. These aerosol species are major components of fine particulate matter (PM) and contribute significantly to visibility impairment. Estimates of ammonia emission factors are both highly variable and uncertain. Emissions factors vary depending on meteorological conditions and seasonal and regional differences in farming practices. Previous ammonia emissions inventories have not adequately characterized seasonal and geographical variations in emissions factors. Recent chemical transport modeling suggests that daily and hourly variability in ammonia emissions is required to model accurately the formation of ammonium nitrate and ammonium sulfates.
In a companion paper, the development of a process-based model for predicting or estimating ammonia emission rates and factors from individual or a group of animal feeding operations at local, regional and national levels was presented. This paper discusses the data requirements and implementation of the process-based ammonia emission model. Preliminary emission estimates developed from the process-based ammonia emission model are also presented. Detailed description of databases used as input values for the process-developed model and recommendations for future improvement on the farm-based data regarding the animal feeding and manure management practices are documented. Where available, comparisons of the new ammonia emission estimates with existing ammonia emission inventories for livestock farms at a local, regional and national level are presented.
The work presented here is sponsored and funded by the Lake Michigan Air Directors Consortium (LADCO).This paper was presented at 14th International Emission Inventory Conference, 11–14 April 2005, Las Vegas, NV.</p