Patents Assigned to Hoffmann-Stafford Tanning Co.
  • Continuous method for reclaiming chromium hydroxide from spent chrome tanning liquors and re-use thereof in subsequent tanning
    Patent number: 3950131
    Abstract: A continuous method is provided for reclaiming chromium compounds which heretofore were discharged as industrial waste from chrome liquor tanneries. The method includes continuous agitation of chrome sludge along with continuous filtration and movement through successive filtering zones. This method is both economically attractive and vital from an ecological standpoint. The reclaimed chromium values are in condition for reconstitution into fresh chrome-tanning liquors.
    Type: Grant
    Filed: June 20, 1973
    Date of Patent: April 13, 1976
    Assignee: Hoffmann-Stafford Tanning Co.
    Inventor: Harland H. Young