Patents by Inventor Nikola B. Videnov

Nikola B. Videnov 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).

  • Method of obtaining granulated and defluorated phosphogypsum
    Patent number: 4162170
    Abstract: A combined method for granulation and defluoration of phosphogypsum, suitable for subsequent fluidized bed disassociation to lime and sulphur dioxide is described. The new phosphogypsum, obtained from phosphoric acid production, containing residual combined fluorine, is dried to reduce its residual water. It is moistened with sulfuric acid and aqueous solutions of binding agent additives and then granulated. The granules are heat-treated at temperatures between 170.degree. C. and 700.degree. C. During the heat treatment the residual fluorine residue is volatilized and the granules increase in strength sufficient for use in subsequent fluidized bed treatments.
    Type: Grant
    Filed: August 28, 1978
    Date of Patent: July 24, 1979
    Assignee: Vish Chimiko-Technologicheski Institute
    Inventors: Ivan N. Grancharov, Fanka D. Tudjarova, Yovka P. Bakalova, Yoncho G. Pelovski, Nikola B. Videnov, Ivan P. Dombalov