Patents by Inventor Lawrence H. Allen

Lawrence H. Allen 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 for producing calcium fulvate from humus material
    Patent number: 6204396
    Abstract: A method produces calcium fulvate from naturally-occurring humus material, such as leonardite, or humic shales. The humus material containing solid fulvic acid and solid humic acid is mixed with water and sodium hydroxide for a first selected period of time to form a solution having a pH of approximately 10.0 thereby solubilizing the fulvic acid and the humic acid. The pH of the solution is reduced to approximately 4.5 and is maintained at the approximately pH 4.5 for second selected period of time thereby precipitating the humic acid as a solid while the fulvic acid remains in solution. The fulvic acid solution is separated from the solid humic acid. The pH of the fulvic acid solution is increased to approximately 13 with calcium hydroxide thereby precipitating the solubilized fulvic acid as calcium fulvate.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: March 20, 2001
    Assignee: Electrolytes, Inc.
    Inventors: Hans W. Rasmussen, Lawrence H. Allen
  • Method for producing magnesium fulvate from humus material
    Patent number: 6147229
    Abstract: A method produces magnesium fulvate from naturally-occurring humus material, such as leonardite, or humic shales. The humus material containing solid fulvic acid and solid humic acid is mixed with water and sodium hydroxide for a first selected period of time to form a solution having a pH of approximately 10.0 thereby solubilizing the fulvic acid and the humic acid. The pH of the solution is reduced to approximately 4.5 and is maintained at the approximately pH 4.5 for second selected period of time thereby precipitating the humic acid as a solid while the fulvic acid remains in solution. The fulvic acid solution is separated from the solid humic acid. The pH of the fulvic acid solution is increased to approximately 13 with magnesium hydroxide thereby precipitating the solubilized fulvic acid as magnesium fulvate.
    Type: Grant
    Filed: December 27, 1999
    Date of Patent: November 14, 2000
    Assignee: Electrolytes, Inc.
    Inventors: Hans W. Rasmussen, Lawrence H. Allen
  • Centrifugal cleaning of pulp and paper process liquids
    Patent number: 5468396
    Abstract: A process for the removal of dispersed contaminants less dense than water from pulp and paper mill process liquids, comprises passing the liquid through a centrifuge and collecting the contaminants as a less dense fraction. The application of this invention to paper industry process liquids provides a means of removing a significant fraction of the wood resin and wood resin soaps from the process stream, thus enabling (1) a greater extent of reuse of filtrates and, hence, less effluents from mills, and (2) fewer problems from wood resin, such as deposit formation, loss of strength of product, and contamination of product with dirt particles.
    Type: Grant
    Filed: March 16, 1994
    Date of Patent: November 21, 1995
    Assignee: Pulp and Paper Research Institute of Canada
    Inventors: Lawrence H. Allen, Christine L. Lapointe
  • Additives for increased retention and pitch control in paper manufacture
    Patent number: 4313790
    Abstract: A process is disclosed for the production of paper and paper-like products which consists of the addition to the papermaking furnish of kraft lignin or modified kraft lignin and poly(oxyethylene).
    Type: Grant
    Filed: March 31, 1980
    Date of Patent: February 2, 1982
    Assignee: Pulp and Paper Research Institute of Canada
    Inventors: Robert H. Pelton, Lawrence H. Allen, Henry M. Nugent