Patents Assigned to Erwin Wessling
  • Patent number: 5507953
    Abstract: The method of cleaning soil contaminated with contaminants includes comminuting contaminated soil to form a comminuted contaminated soil; filling the comminuted contaminated soil into a countercurrent extractor from above under an inert gas atmosphere so that the comminuted contaminated soil moves as a travelling bed downward through the countercurrent extractor; feeding a solvent, advantageously acetone, into a lower portion of the countercurrent extractor so that the solvent flows upward through the travelling bed to form a decontaminated soil at the bottom of the extractor and a contaminant-charged solvent portion taken from a middle portion; supplying a conveying liquid to the lower portion of the countercurrent extractor so as to transfer the decontaminated soil from the countercurrent extractor to a filter device having a belt filter; and separating the decontaminated soil in the filter device into a cleaned soil and a reusable conveying liquid.
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: April 16, 1996
    Assignees: Peter Flakus, Horst Muehr, Erwin Wessling
    Inventors: Rainer Machlitt, Frank Meyer