Patents Assigned to W. R. Grace & Co. of Canada Ltd.
  • Composition and method for dehalogenation and degradation of halogenated organic contaminants
    Patent number: 6083394
    Abstract: A method of creating an environment which promotes dehalogenation and/or degradation of halogenated organic chemical contaminants in water, sediment, or soil by adding a combination of fibrous organic matter and certain multi-valent metal particles to the water, sediment or soil.
    Type: Grant
    Filed: February 7, 1995
    Date of Patent: July 4, 2000
    Assignee: W.R. Grace & Co. of Canada Ltd.
    Inventors: Alan George Seech, James Ewart Cairns, Igor Jiri Marvan
  • Concrete mixing drum cleaning method and apparatus
    Patent number: 5244498
    Abstract: The present invention relates to a method of retarding the set of residual concrete in a concrete holding vessel comprising uniformly directing an aqueous solution containing an effective amount of a set retarding agent against the residual concrete on the inner surface of said concrete holding vessel with sufficient pressure to retard concrete set with less than about 3 gallons of aqueous solution per every 10 lbs. of residual concrete. The present invention also relates to an apparatus which utilizes a minimal amount of wash water.
    Type: Grant
    Filed: April 9, 1991
    Date of Patent: September 14, 1993
    Assignee: W. R. Grace & Co. of Canada Ltd.
    Inventor: Lloyd E. Steinke