The Many and Varied Uses of Anhydrous Ammonia

Anhydrous ammonia, or ammonia in its purest form not diluted in water, is used across all kinds of varying industries and in many different ways. 

It is a complicated compound to obtain. In a process known as the Haber-Bosch process, nitrogen is pulled from the air and combined with a hydrogen source to create anhydrous ammonia. It exists naturally in a gaseous state but can be compressed and kept very cold to form a liquid.

But what is anhydrous ammonia used for? Why go through this long and complex process to create something that is so hard to contain and requires so much compression just to keep it in a liquid state?

There are so many different ways that we rely on anhydrous ammonia for the things we use in our daily lives. Here are a few ways that anhydrous ammonia makes our lives easier:

Agricultural Anhydrous Ammonia

Anhydrous ammonia is one of the most efficient sources of nitrogen as a fertilizer, making it one of the most widely used sources of nitrogen fertilizers in agriculture. The anhydrous ammonia, which is made up of one part nitrogen and three parts hydrogen, is compressed until it takes on a liquid form. In its gaseous state, anhydrous ammonia is 40-percent lighter than air, so it must be compressed to take on a liquid state to fertilize crops.

As soon as this compressed anhydrous ammonia liquid is injected into the soil, it expands into the gas and is absorbed into the moisture within the soil, making it an ideal way to deliver a reliable nitrogen source to crops.

The earth’s atmosphere is 80-percent nitrogen, but plants can’t absorb nitrogen out of the air. Like all plants, crops require nitrogen to be part of a compound like anhydrous ammonia in order to receive the nutrients. 

Of all 16 nutrients that plants require for successful growth, botanists categorize nitrogen as one of the primary three nutrients that are essential for plant growth, alongside phosphorus and potassium. Without nitrogen, crops may grow poorly or develop yellow leaves and look sickly. 

Anhydrous ammonia is very commonly used in agriculture as a plant fertilizer, but it also has other uses in the same industry. The compound also is used in high-moisture grains as a way to prevent mold growth and to add non-protein nitrogen to corn silage. 

Other agricultural uses include:

• An antiseptic that kills 99.99 percent of zoonotic bacteria in animal feed.
• A way to remove microbial contamination in textured beef.

Refrigerants

Anhydrous ammonia is essentially pure ammonia with a very low boiling point of negative 28 degrees. It is used frequently as a refrigerant. In these refrigeration systems, it is stored in closed containers at a very high pressure level.

How does this work? The compressed anhydrous ammonia heats up under pressure, and coils (like the ones found at the back of a refrigerator) heat up as well. These coils let the hot anhydrous ammonia dissipate the heat, and the gas condenses into a high-pressure liquid, which then boils, vaporizes and drops its temperature below that negative-28-degree boiling point, producing a cooling effect. This process repeats on a cycle, drawing energy by absorbing heat from its surroundings to start the heating and cooling process all over again.

Anhydrous ammonia also is used in industrial refrigeration systems, warehouses and food processing facilities—and even in ice rinks and heavy industries that require cooling.

Other Uses

The use of ammonia—in all of its forms—is widespread, and it is used in manufacturing across a wide array of industries. Here are a few additional examples of uses of anhydrous ammonia:

• Anhydrous ammonia is used for air remediation for gaseous emissions, neutralizing the nitrogen oxide pollutants that are emitted from diesel engines. 
• Anhydrous ammonia is used in the manufacture of pharmaceuticals.
• In the textile industry, anhydrous ammonia is used in a variety of ways, including its use to soften cotton. Ammonia also is used in the production of rubber, plastic and leather goods.

Airgas Specialty Products offers world-class, reliable anhydrous ammonia delivery as well as storage repairs, tank inspections and preventative maintenance. We know the level of attention to detail it takes to make anhydrous ammonia usage and storage safe, so no matter what the industry, you can rely on Airgas Specialty Products for all of your anhydrous ammonia needs.

Can we change the way you handle your supply and storage of anhydrous ammonia? Let our experts show you how it’s done. Request a quote from us today.