Model That Predicts Ammonia Emissions from Manure-Stored Buildings in Livestock Farms: A Useful Simulation Tool
In the realm of agriculture, poultry production is a significant contributor to ammonia emissions, with the sector emitting over one million tons annually in the U.S. [5]. A novel approach, known as the alternative mass-balance method, has been developed to estimate ammonia emissions from poultry layer houses more accurately, without the need for direct gas measurements.
This method, based on nitrogen budgeting principles, quantifies inputs and outputs of nitrogen in the system and calculates the difference as ammonia emitted. It involves measuring or estimating nitrogen in feed, poultry excreta, and manure removal, then accounting for nitrogen losses to ammonia volatilization during housing and manure handling.
For U.S. poultry layer houses, this method utilizes data such as feed nitrogen content, feed intake, bird excretion rates, manure collection frequency, and environmental conditions inside the housing. By balancing nitrogen inputs (feed) against nitrogen outputs (manure nitrogen content and nitrogen in birds), the lost nitrogen fraction is attributed predominantly to ammonia emissions.
To implement this method, one needs to know the nitrogen content of the feed, nitrogen content of the egg, nitrogen content of the manure, ash content of the feed, ash content of the manure, ash content of the egg, feed consumption rate, and egg production rate. Sampling should occur on the days that manure is removed from the manure-belt layer house.
Composite feed, egg, and manure samples can be shipped to a nutrient and composition analysis lab for analysis. A typical manure-belt layer house was selected for testing the method, with dimensions of 161.6 m in length, 15.9 m in width, and 7 m in height.
The alternative mass-balance method has proven to be a relatively simple, inexpensive, and accurate method for estimating ammonia emissions. However, it's important to note that the most accurate measurement method for ammonia emissions from animal facilities is continuous monitoring of ventilation airflow rates and ammonia concentrations using ammonia gas analyzers and fan operation sensors.
This method was developed with financial support by the Research Enhancement Competitive Grants Program of the Ohio Agricultural Research and Development Center. While the search results do not provide a detailed step-by-step protocol for the alternative mass-balance method applied to U.S. poultry layer houses, the approach is generally well documented in the scientific literature on agricultural emissions inventories and environmental impact assessments.
The model overestimated the NH emission factor because it estimates total nitrogen emission, an upper limit of NH-N emission. Despite this, the method provides a valuable tool for poultry producers, as most do not have effective tools to estimate ammonia for better nitrogen nutrient management and meeting the EPCRA reporting requirement. A minimum of 21-24 sampling and analysis events are suggested to obtain a statistically reliable ammonia (NH) emission factor for the MB layer houses with a maximum of 15% error.
In conclusion, the alternative mass-balance method offers a promising solution for estimating ammonia emissions from poultry layer houses, providing a more accurate and cost-effective approach compared to traditional methods. This development is a significant step towards reducing ammonia emissions in the agriculture sector and promoting sustainable poultry production.
The fact sheet was reviewed by Karen Mancl, Professor, and Larry Brown, Professor, Food, Agricultural and Biological Engineering, The Ohio State University.
- The alternative mass-balance method, derived from nitrogen budgeting principles, is a novel approach for estimating ammonia emissions from poultry layer houses accurately.
- This method is based on measuring or estimating nitrogen in feed, poultry excreta, and manure removal, and accounting for nitrogen losses to ammonia volatilization during housing and manure handling.
- For accurate estimates, it's crucial to know the nitrogen content of the feed, nitrogen content of the egg, nitrogen content of the manure, ash content of the feed, ash content of the manure, ash content of the egg, feed consumption rate, and egg production rate.
- Sampling should occur on the days that manure is removed from the manure-belt layer house, with composite samples shipped to a nutrient and composition analysis lab for analysis.
- The alternative mass-balance method is relatively simple, inexpensive, and accurate compared to traditional methods, but continuous monitoring of ventilation airflow rates and ammonia concentrations using ammonia gas analyzers and fan operation sensors is the most accurate method.
- The development of this method received financial support from the Research Enhancement Competitive Grants Program of the Ohio Agricultural Research and Development Center.
- Despite overestimating the NH emission factor due to total nitrogen emission estimation, the method offers a valuable tool for poultry producers, aiding them in nitrogen nutrient management and meeting the EPCRA reporting requirement.
- A minimum of 21-24 sampling and analysis events are suggested to obtain a statistically reliable ammonia (NH) emission factor for the MB layer houses with a maximum of 15% error.
- This method, reviewed by Karen Mancl and Larry Brown, Professors at The Ohio State University, presents a promising solution for reducing ammonia emissions in the agriculture sector and promoting sustainable poultry production. Additionally, this method's impact on health-and-wellness, environmental-science, education-and-self-development, data-and-cloud-computing, technology, business, personal-finance, lifestyle, food-and-drink, and even casino-and-gambling could potentially be studied, as they are all interconnected areas of interest.
