Westinghouse Electric Company has announced that it has signed an agreement with Siempelkamp Nukleartechnik GmbH (SNT) subsidiaries Siempelkamp Nuclear Services, Inc (SNS) and NIS Ingenieurgesellschaft mbH (NIS) to jointly market and provide Passive Autocatalytic Recombiner (NIS-PAR) technology and analysis to the nuclear industry in the U.S. and international markets.

The NIS-PAR technology uses hydrogen recombination to prevent the buildup of hydrogen gas, or other flammable gases like carbon monoxide that can collect and create an explosive atmosphere. The function is completely passive and self-starting at low temperatures and in steam environments. It is driven by natural convection generated by the heat from the hydrogen recombination.

Chimney elongation of the NIS-PAR devices boosts the depletion rate. Each NIS-PAR has a hood to protect against containment spray. A great number of international test programs were conducted with the NIS-PAR module which verifies operability under accident conditions.

A great variety of NIS-PAR device options allows the flexible adaption to the plant-specific needs and for the needed depletion rates in the nuclear power plant containment, auxiliary building or spent fuel pool locations. In addition, NIS-PAR allows for the periodic testing and cleaning of cartridges should they be exposed to contaminants.

Westinghouse will perform the design and analysis of the hydrogen control system using codes like MAAP and MELCOR to predict the generation and transport of hydrogen for severe accident scenarios and the number of NIS-PARs needed to preclude hydrogen detonation. Under terms of the agreement, Siempelkamp will provide joint marketing support, the NIS-PAR devices, test and cleaning devices, as well as needed supports for mounting the devices.

"This partnership between Siempelkamp and Westinghouse will provide additional solutions to enhance safety across the global fleet," said Doug Holderbaum, Westinghouse director for Post-Fukushima Safety Products and Services. "It demonstrates yet another example of our commitment to offer products and services that deliver real, differentiating value to the customer."

Westinghouse provides a full complement of safety-enhancing solutions to keep pressurized water reactor (PWR) and boiling water reactor (BWR) nuclear plants operating safely and competitively. The passive autocatalytic hydrogen recombiners are part of the range of products and services Westinghouse provides to the global nuclear fleet to support the implementation of plant safety enhancements following the events at Fukushima.