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ARS Home » Research » Publications at this Location » Publication #123511
Title: IMPROVING UNIFORMITY OF ANHYDROUS AMMONIA APPLICATION

Author
item HANNA, H - IOWA STATE UNIVERSITY
item WHITE, M - IOWA STATE UNIVERSITY
item BOYD, P - IOWA STATE UNIVERSITY
item Colvin, Thomas
item BAKER, T - IOWA STATE UNIVERSITY

Submitted to: Extension Publications
Publication Type: Popular Publication
Publication Acceptance Date: 6/5/2001
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Each year Iowa corn growers apply over one billion pounds of nitrogen as anhydrous ammonia. On an applicator, anhydrous ammonia begins as a high- pressure liquid inside the field nurse tank. Pressure depends on the temperature of the ammonia. On most applicators, ammonia moves by its own pressure downstream through hoses connecting the tank, regulator, distribution manifold, and subsurface injection knives. Ammonia generally boils throughout its travel inside the applicator. Understanding how some of the ammonia changes from a liquid to a gas can help explain application inefficiencies. Because of a tendency for different regions of a manifold to have greater or lessor flows through its outlet ports, we recommend that ports not be connected sequentially around the manifold perimeter to adjacent knives left-to-right across the applicator. That is, adjacent knives on the applicator should not be connected to adjacent outlet ports on the manifold. At application rates of 50 to 75 lbs. N/ac or higher application rates with a properly sized outlet ring, a Vertical Dam manifold has generally shown better distribution than a conventional manifold. Newer, non-conventional manifolds tested at Iowa State University have shown increased uniformity.