Ammonia (NH3) is one of the most commonly produced industrial chemicals in the United States. It is used in industry and commerce, and it also exists naturally in humans and in the environment. Ammonia is essential for many biological processes and serves as a precursor for amino acid and nucleotide synthesis. In the environment, ammonia is part of the nitrogen cycle and is produced in soil from bacterial processes. Ammonia is also produced naturally from decomposition of organic matter, including plants, animals, and animal wastes.
Some chemical/physical properties of ammonia are:
- At room temperature, ammonia is a colorless, highly irritating gas with a pungent, suffocating odor.
- In pure form, it is known as anhydrous ammonia and is hygroscopic (readily absorbs moisture).
- Ammonia has alkaline properties and is corrosive.
- Ammonia gas dissolves easily in water to form ammonium hydroxide, a caustic solution and weak base.
- Ammonia gas is easily compressed and forms a clear liquid under pressure.
- Ammonia is usually shipped as a compressed liquid in steel containers.
- Ammonia is not highly flammable, but containers of ammonia may explode when exposed to high heat.
Ammonia is found in a wide variety of applications throughout the United States. Anhydrous ammonia tanks are a common sight in rural areas where there is room for them to stand. (Anhydrous ammonia is “pure” ammonia, as opposed to ammonia dissolved in water, also known as “aqueous” ammonia.)
Concern about ammonia emissions in the air and water continues to grow, both officially and unofficially. As the U.S. Environmental Protection Agency (EPA) moves to further reduce ammonia concentrations in surface waters, common water treatment methods transform what had been a water pollution problem into an air pollution issue.
As the EPA continues to reduce the amount of fine particulate matter (also known as PM2.5 - particulate matter less than 2.5 microns in diameter), there is increased concern about ammonia emissions and their effect as a precursor to fine particulate formation.
EPA regulations have focused on controlling PM2.5 because these particles are statistically associated with increased incidence of pulmonary disease and reduced lung function, cardiac arrest, and premature death. The deposition of these particles degrades sensitive terrestrial and aquatic ecosystems, and, due to their light scattering properties, can affect the climate.
The concern about the hazards of ammonia, including its effect on waterways and its tendency to contribute to fine particulate formation, has resulted in the need to examine available methods for the control of ammonia emissions. If you have any questions about ammonia emissions, please contact us.