Treating Gases [g21f-9/02] Patents (Class 976/DIG378)
  • Patent number: 5492686
    Abstract: A first partial flow of an H.sub.2 -air-steam mixture is passed through a first channel and recombined by contact with a first channel wall having a catalytic coating. In addition to the first partial flow, a second partial flow of the mixture is passed through a second channel having a second channel wall and is ignited by being fed past preferably metallic ignition elements being heated to the H.sub.2 ignition temperature upon reaching or exceeding an ignition limit. Under these circumstances, heat liberated during the catalytic reaction in the first channel is at least partially transmitted to the second channel for the purpose of preheating it. The novel process functions both at the lower and at the upper ignition limit and recombines even at unignitable H.sub.2 concentrations. A device with which the process can be carried out is also described.
    Type: Grant
    Filed: January 28, 1994
    Date of Patent: February 20, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventor: Axel Hill
  • Patent number: 5368633
    Abstract: A system for collecting, transferring and storing radioactive gas released from other radioactive materials. In the described process, gas pump (24) removes gas from a headspace volume within an unvented radioactive material storage vessel (8). The gas is cooled in an aftercooler (28) and discharged into a receiver (32). As pressure in receiver (32) increases, compressed gas is transferred to a selected pressurized decay vessel (44 or 50), in which the radioactive gas remains for a predetermined decay period. After expiration of decay period, decayed gas is either recycled back to the radioactive material storage vessel (8) via recycled gas recirculation line (52) and pressure reducing valve (54), or is discharged to atmosphere through an activated carbon and high-efficiency particulate filters (48), removing remaining undecayed radioactive gas and particulate daughter products.
    Type: Grant
    Filed: August 12, 1993
    Date of Patent: November 29, 1994
    Assignee: Morrison-Knudson (an Idaho corporation)
    Inventors: Joseph T. Foldyna, Donald J. Carpenter, John M. Cron
  • Patent number: 5252258
    Abstract: The invention provides a method of recovering and storing radioactive iodine by a freeze vacuum drying process, in which off-gas generated when spent fuel is subjected to shearing and dissolving treatments is scrubbed and, when necessary, is subjected to a precipitation treatment by addition of additives, after which waste liquid containing radioactive iodine is freeze-dried by a freeze vacuum drying process to recover radioactive iodine as iodine compounds. As a result, since the radioactive iodine does not vaporize, release of the radioactive iodine into the environment can be eliminated. In addition, consumption of a collecting agent such as silver zeolite for collecting vaporized radioactive iodine can be reduced. The iodine compounds containing the recovered radioactive iodine is given the same composition as a stable, naturally occurring mineral and is solidified and mineralized as by a high-pressure press. This makes it possible to store long half-life .sup.
    Type: Grant
    Filed: August 15, 1991
    Date of Patent: October 12, 1993
    Assignee: Doryokuro Kakunenryo Kaihatsu Jigyodan
    Inventors: Katsuyuki Ohtsuka, Jin Ohuchi, Toru Suzuki
  • Patent number: 5078960
    Abstract: A device for relieving the pressure in a containment of a nuclear power station. The device includes a filter unit for filtering compressed air from the containment and discharging the air to the atmosphere. Radioactive substances entrained in the compressed air are removed. The filter unit includes an aerosol-filter subunit located within the containment, and a molecular-sieve subunit for iodine filtering located outside the containment in an auxiliary equipment building. Ducts and fittings connect the subunits of the filter unit. At least one duct extends through the containment wall and can be opened and closed by fittings which can be actuated in the event of a failure.
    Type: Grant
    Filed: October 5, 1989
    Date of Patent: January 7, 1992
    Assignee: RWE Energie Aktiengesellschaft
    Inventors: Diethart Berg, Claus-Gert Reddehase, Manfred Wolf