Patents by Inventor Kjell R. Waerstad

Kjell R. Waerstad has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Acid type solid urea-nitric fertilizer
    Patent number: 4507139
    Abstract: The present invention relates to the reaction of phosphate rock with nitric acid and urea to produce nitrogen-phosphorus containing slurries, which slurries, in turn, may be granulated and dried to produce solid N-P fertilizer products with agronomically advantageous low pHs (1.0-4.0). The products have excellent storage characteristics. The improved properties of these products result partially from the formation of a new compound, Ca(H.sub.2 PO.sub.4)(NO.sub.3).CO(NH.sub.2).sub.2, which was discovered during the course of the investigation that led to the instant invention.
    Type: Grant
    Filed: October 26, 1984
    Date of Patent: March 26, 1985
    Assignee: Tennessee Valley Authority
    Inventors: Jack M. Sullivan, Yong K. Kim, Kjell R. Waerstad
  • Process for the production of solid urea-nitric phosphate fertilizer products
    Patent number: T105301
    Abstract: The present invention relates to the reaction of phosphate rock with nitric acid and urea to produce nitrogen-phosphorus containing slurries, which slurries may be granulated and dried to produce solid N-P fertilizer products with agronomically advantageous low pHs (1.1-4.0). Products with optimum physical and chemical properties were discovered by investigating the characteristics of each individual material as a function of the nitric acid acidulation ratio (mole ratio HNO.sub.3 :CaO) and the mole ratio urea:CaO present in each product. Acidulation ratios ranged from 1.2 to 2.1 while ratios urea:CaO ranged from 1.6 to 4.0. Selected products with optimum physicochemical properties are tabulated below:______________________________________ Acidulation Ratio Ratio Melting HNO.sub.3 :CaO, M/M Urea:CaO, M/M Grade Pt, .degree.C. ______________________________________ 1.2 2.2 23.8--11.7--0 137-139 1.4 2.4 25.0--11.0--0 136 1.6 2.8 25.9--9.9--0 133-137 1.8 3.0 26.4--9.2--0 134-135 2.0 3.3 27.2--8.7--0 130 2.1 3.
    Type: Grant
    Filed: May 21, 1984
    Date of Patent: April 2, 1985
    Inventors: Jack M. Sullivan, Yong K. Kim, Kjell R. Waerstad