Patents by Inventor Ursula Hollwedel

Ursula Hollwedel 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).

  • Patent number: 7931753
    Abstract: A method to remove deposits containing magnetite and copper from a container, particularly from a steam generator of a nuclear power plant. In a first step, the container is treated using an alkaline cleaning solution containing a complexing agent forming a soluble complex with iron ions, a reducing agent, and an alkalizing agent. In a second step a further complexing agent forming a more stable complex with iron III ions than the complexing agent used in the first step and an oxidant are added to the cleaning solution of the first step present in the container.
    Type: Grant
    Filed: September 8, 2009
    Date of Patent: April 26, 2011
    Assignee: Areva NP GmbH
    Inventors: Konrad Bitter, Ursula Hollwedel, Enkhtsetseg Batchuluun
  • Publication number: 20100313913
    Abstract: A physical-chemical method for cleaning a secondary chamber of a heat exchanger in a nuclear facility, includes drying the secondary chamber and introducing a cleaning solution into the secondary chamber to treat deposits present in the secondary chamber.
    Type: Application
    Filed: June 16, 2010
    Publication date: December 16, 2010
    Applicant: Areva NP GmbH
    Inventors: Ursula Hollwedel, Franz Ammann
  • Publication number: 20100012154
    Abstract: A method to remove deposits containing magnetite and copper from a container, particularly from a steam generator of a nuclear power plant. In a first step, the container is treated using an alkaline cleaning solution containing a complexing agent forming a soluble complex with iron ions, a reducing agent, and an alkalizing agent. In a second step a further complexing agent forming a more stable complex with iron III ions than the complexing agent used in the first step and an oxidant are added to the cleaning solution of the first step present in the container.
    Type: Application
    Filed: September 8, 2009
    Publication date: January 21, 2010
    Applicant: AREVA NP GMBH
    Inventors: Konrad Bitter, Ursula Hollwedel, Enkhtsetseg Batchuluun
  • Publication number: 20050126587
    Abstract: A method for cleaning steam generating devices of a pressurized water reactor treats the devices on their secondary sides at high pressure and high temperature. An aqueous cleaning solution is employed with EDTA, a reducing agent, and an alkalizing agent. Morpholine is used as the alkalization agent. A molar morpholine-concentration, which is at least as great as the molar concentration of EDTA, is selected. Hydrazine and/or formaldehyde are/is used as the reducing agent at a ratio to EDTA between 1:6 and 1:1.
    Type: Application
    Filed: January 27, 2005
    Publication date: June 16, 2005
    Inventors: Konrad Bitter, Ursula Hollwedel, Silvia Schuss
  • Patent number: 6695927
    Abstract: A method and a solution are provided for cleaning a container, in particular a boiler of a conventional power station. The container is degreased and pickled in one method step using an alkaline cleaning solution. A suitable cleaning solution includes, for example, an ammonium EDTA salt, hydrazine and a surfactant.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: February 24, 2004
    Assignee: Siemens Aktiengesellschaft
    Inventors: Ursula Hollwedel, Klaus Kuhnke