4/21/2010

 Fertilizer use exploded after WWII  Plants built during the war to supply nitrogen for bombs; after war supplied ammonia for fertilizer  Most of ammonia applied in 1940’s was ammonium nitrate pellets, but this was highly explosive  Research on anhydrous ammonia started in mid 1940’s  1943 researchers at Mississippi Agricultural Experiment Station developed a way of injecting anhydrous into soil

 At local coop in Grant county  UAN - $280/ton   $0.50/lb of N  Anhydrous Ammonia $390/ton   $0.23/lb of N

 Do a good job of applying consistent amounts over a field, but not to each knife.  Poor distribution of ammonia is more evident in strip-till

 Anhydrous ammonia is a liquid under pressure  A small percentage of ammonia vaporizes when pressure drops  Majority of mass in ammonia is in liquid while gaseous ammonia is a large part of the volume  Up to 90% of space inside metering valve can be gas, making uniform distribution difficult

 Traditional systems  Over-apply to compensate for rows with less ammonia  Application at an angle to planting rows  Equal hose lengths between the manifold and knife  Unused manifold ports should be plugged equally  Upgrade to newer metering systems

 aNH3 Equaply System  Maintains constant pressure of ammonia distributed to knives  Allows for anhydrous ammonia to be distributed over a wide variation in tank pressure  Flow control system is used to assure rate of application and to allow for variable rate application  Liquimatic System  No need for heat exchanger  Works almost like a steam trap  Can handle higher rates

 Nurse Tank  Requires a high flow globe valve at the nurse tank  For high rates, dual tanks are recommended  Heat Exchanger  Cools anhydrous ammonia below its boiling point and condenses vapor into liquid  Pump increases pressure of liquid and lowers the boiling point

 Pump  Uses a Hypro centrifugal pump with a hydraulic motor  Avoids surges like in a piston pump  Pump keeps anhydrous ammonia at a liquid until it is split evenly at the manifold

 Flow and Measurement Control  Signals from flow sensor go to a cab console which operates the servo valve  Can interface with AgLeader, Raven, and John Deere Greenstar II  Also uses a gauge tree to monitor flow to individual rows

 Monitor and Gauge tree

 Manifolds and Orifices  From servo valve, anhydrous ammonia goes to one or more manifolds that are controlled by an electronic on/off valve  From these manifolds, EVA ammonia tubing runs to individual knives  Connecting lines also go to gauge tree

 Accurate control of anhydrous ammonia application  Ability to achieve variable rates  Decrease of streaking in fields  Can be used in no-till situations

 Anhydrous Ammonia flows from tank to a Liquimatic tower  Tower has a metal dam in it making incoming vapor and liquid move upward  When pressure from vapor reaches a certain point, a solenoid opens a valve and lets off liquid  This also keeps a head pressure on liquid ammonia, ensuring it remains a liquid

 Flow meter after the tower is metering only liquid which makes it much more accurate

 Eliminates the need for a heat exchanger  Allows for higher rates  Can apply up to 80 gallons/minute  60 ft applicator can apply 250 lb/ac anhydrous at 12 mph