Patents by Inventor Patrick V. Cashell

Patrick V. Cashell 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 treating waste containing stainless steel
    Patent number: 5877394
    Abstract: A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe.sub.3 O.sub.4. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe.sub.2 O.sub.3. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: March 2, 1999
    Inventors: Stephan T. Kujawa, Daniel M. Battleson, Edward L. Rademacher, Jr., Patrick V. Cashell, Krag D. Filius, Philip A. Flannery, Clarence G. Whitworth
  • Method of operating a centrifugal plasma arc furnace
    Patent number: 5731564
    Abstract: A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe.sub.3 O.sub.4. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe.sub.2 O.sub.3. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater.
    Type: Grant
    Filed: February 5, 1996
    Date of Patent: March 24, 1998
    Assignee: MSE, Inc.
    Inventors: Stephan T. Kujawa, Daniel M. Battleson, Edward L. Rademacher, Jr., Patrick V. Cashell, Krag D. Filius, Philip A. Flannery, Clarence G. Whitworth