DESIGN AND CONSTRUCTION OF A NEW LIQUID EFFLUENT TREATMENT PLANT FOR THE UKAEA DOUNREAY PROTOTYPE FAST REACTOR

摘要

The purpose of the project is to provide a facility at the Prototype Fast Reactor (PFR) at Dounreay that can process the radioactive liquid wastes arising from decontamination and decommissioning operations, prior to discharge to the site liquid effluent system and onward for discharge to sea in accordance with agreed discharge authorisations. It is intended to decommission PFR over the next 30 years requiring a number of separate but integrated projects including the buffer store pond and the irradiated fuel cave. The decommissioning activities will generate a variety of effluent streams, many containing sodium hydroxide from steam cleaning of sodium wetted components, each requiring differing levels of treatment to ensure their suitability for discharge. Typically the liquid wastes will require filtration, neutralisation, and the removal of radioactive contaminants, such as caesium and cobalt. The existing Effluent Treatment Plant at PFR was designed to filter and neutralise effluent streams. This plant is no longer able to carry out neutralisation operations and has no capability to remove radioactive contaminants. These factors contribute, along with the physical conditions, to the plant being unable to conform to modern regulatory standards leading to the requirement for a new Effluent Treatment Plant (ETP).