Nitrogen-containing Patents (Class 71/35)
  • Patent number: 4202683
    Abstract: Langbeinite (2MgSO.sub.4,K.sub.2 SO.sub.4) is reacted with diammonium phosphate (NH.sub.4).sub.2 HPO.sub.4 to yield a dry farm field fertilizer of grade 21-12-7+1.22 Mg.The chemical process is also adjusted for a dry farm field "double cropping" fertilizer.The cost of the basic liquid fertilizer containing Magnesium has been likewise reduced.These fertilizers contain magnesium in the presence of phosphorus.The micronutrients, Zn, Cu, Fe, Mn and B may be added in rates proportional to the deficiency shown by soil tests.
    Type: Grant
    Filed: April 14, 1977
    Date of Patent: May 13, 1980
    Inventor: Edwin K. Schuman
  • Patent number: 4152402
    Abstract: An improved process for the purification of wet-process phosphoric acid (WPPA) with acetone and ammonia. The main product is the purified acid and a byproduct is the impure acid fraction in a liquid form containing most of the impurities including the added ammonia. The WPPA is mixed with acetone and the specified amount of ammonia to form two liquid phases that separate rapidly. The top layer contains about 75 percent of the phosphoric acid, nearly all the acetone, and a small fraction of the impurities. The bottom liquid layer has a viscosity usually in the range of 40 to 2500 centipoises, depending on the acid concentration and the amount of ammonia used. The acetone is distilled from the two liquid phases for recycle to the process.
    Type: Grant
    Filed: February 24, 1978
    Date of Patent: May 1, 1979
    Assignee: Tennessee Valley Authority
    Inventors: Henry K. Walters, Jr., Yong K. Kim, John D. Hatfield
  • Patent number: 4019890
    Abstract: Granular slow-releasing fertilizers completely coated with water-resisting resin are produced in such a manner that the coated granules do not stick together, through one step operation by spraying a solution of the resin which has the property capable of maintaining the solution state while it is hot but turning into jelly-like gel when it is cooled, on granules of fertilizer and drying the said granules with a high speed drying hot air on the spot upon being sprayed with the solution of the resin.
    Type: Grant
    Filed: December 3, 1974
    Date of Patent: April 26, 1977
    Assignee: Chissoasahi Fertilizer Co., Ltd.
    Inventors: Toshio Fujita, Chigo Takahashi, Masanari Ohshima, Tsunezo Ushioda, Hirozo Shimizu
  • Patent number: 4008064
    Abstract: The invention provides an improved pan granulation process for the production of low-water or substantially anhydrous nitrogenous compounds. Hot nitrogenous melt and cooled particulate solids are fed to a rotating pan to form a cresent-shaped bed of rolling or tumbling particles, the thickness or depth of the bed increasing in the direction towards the periphery of the pan and its overflow sector, i.e. position 2 o'clock to position 6 o'clock when the pan surface is regarded as a clock face and the rotation of the pan is counter-clockwise. The cooled solid particles are fed to the pan at a point where the depth of existing material is small, desirably substantially zero, preferably in position 7 to 8 o'clock, if need be by feeding the particles through a tube or the like which extends into the tumbling material on the pan to the proximity of the surface of the pan itself. Subsequently, the cooled particles will then be covered by and with warmer particles tumbling over them.
    Type: Grant
    Filed: February 12, 1975
    Date of Patent: February 15, 1977
    Assignee: Norsk Hydro A.S.
    Inventor: Oyvind Skauli