Patents Assigned to Hawkeye Chemical Company
  • Patent number: 4578105
    Abstract: A method for producing storage stable ureaform dispersion fertilizers by: reaction of urea and monomethylolurea in aqueous solution at a pH between 3.0 and 4.5 with a temperature between 25.degree. and 75.degree. C. until between 15 and 40 percent of the total nitrogen has been converted to form a dispersion of finely divided water insoluble ureaform particles; neutralizing; and admixing a water-insoluble, film-forming oil until the dispersed ureaform particles are coated with sufficient oil to prevent contact between the ureaform particles and the aqueous solution. The water insoluble, film-forming oils found effective include fatty acids, fatty acid esters, castor oil, castor oil esters, alkoxylated castor oils, and alkoxylated alkyl phenols. The amount of film-forming oil required to coat the ureaform particles is between 0.1 and 1.0 percent of the aqueous ureaform dispersion. To prevent settling of the coated ureaform particles a xanthan gum, or iota carrageenan thickener is added.
    Type: Grant
    Filed: January 7, 1985
    Date of Patent: March 25, 1986
    Assignee: Hawkeye Chemical Company
    Inventor: William P. Moore
  • Patent number: 4519831
    Abstract: A method of converting sewage sludge solids into dense controlled release, attrition resistant fertilizer agglomerates is disclosed. The method is carried out by forming a fertilizer premix from dry sewage sludge solids and uncondensed liquid ureaform. Acidic material, preferably phosphoric acid, is distributed throughout the premix to bring the pH to between 4 and 6, and the premix is heated for 5 to 60 minutes to 120.degree. C. The heated premix is compressed between solid surfaces at pressures between 500 and 10,000 pounds per square inch to form agglomerates.The method is preferably carried out on a continuous basis using a heated blender and conveyor for blending and heating the fertilizer premix containing the sewage sludge solids, liquid ureaform, and phosphoric acid. Continuous compacting rollers are used to convert the premix to fertilizer agglomerates which may be readily broken up and screened to any desired fertilizer particle size range.
    Type: Grant
    Filed: October 17, 1983
    Date of Patent: May 28, 1985
    Assignee: Hawkeye Chemical Company
    Inventor: William P. Moore
  • Patent number: 4483877
    Abstract: An improved method of producing silage for use as ruminant feed, whereby green fodders are ensiled with about 1 percent of an additive containing methylolurea and methylenediurea in a weight ratio between 1 and 20 to 1, sufficient free urea to prevent reversion to free formaldehyde, a buffering agent to maintain pH, and water. The method preserves contained natural protein, substantially prevents growth of mold, and increases crude protein content, palatability, and feed efficacy. Operative feature of the method is the discovery that a methylolureamethylenediurea-urea solution may be reacted to a point where it will not sterilize the bacteria needed to ferment contained sugars to carboxylic acids, but will protect the silage against mold formation and natural protein degradation. A process for producing the required silage additive from urea, formaldehyde, ammonia, alkali, and water is provided.
    Type: Grant
    Filed: January 25, 1983
    Date of Patent: November 20, 1984
    Assignee: Hawkeye Chemical Company
    Inventor: William P. Moore
  • Patent number: RE31801
    Abstract: A clear, storable, aqueous solution of partially condensed urea and formaldehyde substantially free of formic acid supplies non-burning and slow-releasing plant food nitrogen when applied directly to the foliage of living grasses, and agricultural and ornamental plants or to soils having neutral or acid surfaces. The substantially ammonia free solution has a pH between 7.5 and 9.8 and contains added buffering agents so that between 0.05 and 0.30 milliequivalents of phosphoric acid are required to reduce pH of one gram to 7.0; and is prepared by the partial condensation of from 1.5 to 2.0 mols urea with 1.0 mol formaldehyde for 20 to 300 minutes at temperatures between 75.degree. and 90.degree. C. with between 0.05 and 0.3 milliequivalents of alkali hydroxide per gram of solution as catalyst.
    Type: Grant
    Filed: November 15, 1982
    Date of Patent: January 15, 1985
    Assignee: Hawkeye Chemical Company
    Inventor: William P. Moore, Jr.