Resources Contact Us Home
Method for producing fertilizer grade DAP having an increased nitrogen concentration from recycle

Image Number 8 for United States Patent #6241796.

A process for the preparation of granular fertilizer grade DAP (a product composed of ammonium phosphates, principally diammonium phosphate, resulting from the ammoniation of phosphoric acid, as defined in Official Publication No. 52 of the Association of American Plant Food Officials, dated 1999) comprising partially preneutralizing orthophosphoric acid with ammonia, completing the ammoniation of the orthophosphoric acid with ammonia in a rotary ammoniator-granulator to provide granular DAP, sizing the granular DAP to provide the granular DAP product, reducing the particle size of the oversized granular DAP, and recycling the undersized granular DAP and the sized-reduced oversized granular DAP to the ammoniator-granulator. The ammoniacal nitrogen concentration of the granular DAP recycle, hence the granular DAP product, is enhanced by subjecting the finely-divided recycled granular DAP to anhydrous gaseous ammonia which is at a super atmospheric pressure and which is at a temperature sufficient to maintain said anhydrous ammonia in the gaseous state. The increase in the ammoniacal nitrogen concentration is a function of the absolute ammonia pressure, the initial moisture content of the granular DAP recycle, and the contact time of the ammonium with the granular DAP recycle.

  Recently Added Patents
Device chip carriers, modules, and methods of forming thereof
Plants and seeds of corn variety CV092363
System and method to obtain signal acquisition assistance data
Electromagnetic sensor cable and electrical configuration therefor
Rose plant named `ESM R057`
Emulsions containing arylboronic acids and medical articles made therefrom
Polarized film apparatus with bands of alternating orientation
  Randomly Featured Patents
Method and apparatus for modified baud rate sampling
Relationship maintenance in an image process
Method and system for finding structures in multi-dimensional spaces using image-guided clustering
Limited slip differential
XYZ isotropic radiator antenna
Voltage-controlled oscillator preventing irregular oscillation
Method of growth of a digital switchblock
Wall-mounted countertop support bracket
Color cathode ray tube having improved arrangement of electron beams
Method to print photoresist lines with negative sidewalls