RESEARCH PROJECT PROMETEUS
AIM OF THE PROJECT
PROMETEUS is a joint research project, funded by the German Federal Ministry of
Education and Research (BMBF). The focus of the R&D project lies on the development of a disposal concept for radioactive mercury and mercury-containing waste, which will be experimentally validated by the collaboration partners Forschungszentrum Jülich GmbH (Institute of Energy and Climate Research – Nuclear Waste Management) and Aachen
Institute for Nuclear Training GmbH. The aim of the PROMETEUS project is to develop a qualified method for the characterization, quantification, decontamination and disposal of mercury-containing waste in order to allow waste producers to recycle and/or dispose their residues.
PROJECT DURATION: JUNE 1st 2016 - MAY 31st 2019
Generally, mercury-containing residues, which originate from a variety of industrial and commercial applications, pose a risk to the environment in the case of improper handling or storage. In particular, mercury, which e.g. was used as a sealing material in hot cells, is usually classified as radioactive due to contaminants and must be treated as radioactive waste accordingly. This also includes activated mercury, which accrues from spallation targets in research accelerator facilities.
Previous concepts for the disposal of mercury-containing waste consider only waste contingents which are of no radiological concern and whose composition is known on account of their origin. Provided that mercury-containing waste results from the dismantling of nuclear facilities, it cannot be dismissed from the regulation under the German Atomic Energy Act and its related legal ordinances due to possible contamination or activation.
OBJECT OF THE R&D PROJECT
A decontamination process for mercury-containing waste will be developed, in which the radionuclides will be separated and the decontaminated mercury can be recycled or disposed of as conventional hazardous waste. For this purpose, these contaminations have to be characterized chemically and radiologically.
Gamma spectrometric measurements are used to quantify the contained radionuclides for a clearance procedure. Indetectable radionuclides (pure alpha and beta emitters) are quantified by destructive analytical methods and will be used to deduce a nuclide vector. The gamma self-shielding due to the high density of mercury results in elevated requirements concerning the characterization procedures.
As part of the PROMETEUS project, a disposal concept will be developed and experimentally tested. This disposal concept will include a guide for documentation, treatment and packaging of mercury-containing waste. Furthermore, it could partially be used for other water-polluting hazardous wastes. For radioactive residues from decontamination, a conditioning process for final disposal will be developed. This requires the conversion and immobilizing of mercury in a durable matrix according to the requirements of ultimate waste storage.