VT Nuclear Services
Gerald Taranto has assisted Babcock International (and its predecessor companies VT Nuclear Services, BNG Project Services and BNFL Environmental Services) by providing expertise in the following areas:
- Acting as Intelligent Customer for the specification for the enhancements to the SIMUL8 discrete event simulation modelling software, which significantly improved the development of throughput modelling for radioactive waste management and decommissioning activities. This included software proving on behalf of the customer.
- Supporting the design of radioactive waste retrieval and processing plants by developing throughput models.
- Carrying out FMECA studies and recommending design changes.
- Developing OR Simulation models.
- Developing ARM strategies
- Producing Life Cycle Cost model which resulted in significant cost savings.
- Supporting optioneering activities through a structured approach to using quantified data.
- Developing spares philosophy for operational plant.
- Production of procedural documentation.
- Providing training in the use of the customised Simul8 software.
- Providing training in ARM philosophy and techniques.
- Providing training in FMECA.
Gerald Taranto has added significant value to Babcock International’s activities in the above areas.
Andy Carr: Consultancy Group Manager – Power Generation, Babcock International Group
VT Nuclear Services: Bugey APD Project
Background
The Bugey APD Project was undertaken by VT Nuclear Services (now Babcock International) in the period 2005-2008 in cooperation with EDF in France. The project objective was to develop the detailed dismantling methodologies, programme and safety justification for the complete dismantling of the 540MWe gas cooled graphite moderated reactor located at the Bugey site some 35km east of Lyon in France. The work included the development of conceptual designs of all dismantling equipment and waste processing plant to prepare the resulting wastes for disposal.
The reactor is housed within a pressure vessel, referred to as the “caisson”, this is a pre-stressed concrete structure some 56m high by 30m diameter, with the wall thickness of approx 5m and the top and bottom caps being 8m thick. The internal cavity occupied by the core assembly is 17m diameter and 40m high. The core assembly comprises approximately 16,000 graphite bricks, a total of approximately 2000Te of graphite, which occupies the upper part of the vessel, supported on a steel skirt and support floor. Within the caisson, and below the core, are 52 heat exchanger modules, each module measuring 1.1×1.1x8m and weighing approximately 50Te. The reactor internals include a further 500Te of graphite shielding rods and 2600Te of supporting steelwork, all of which has to be cut up in-situ and removed.
The dismantling of the reactor is an extremely complex task involving the use of extensive concrete coring and cutting operations to gain access into the caisson, followed by the installation of a massive (1200Te rotating platform) from which will be deployed a range of tools (grabs, shears and hot cutting devices) to remove the reactor internals and the inner skin of activated concrete from the caisson itself.
Services
Taranto Consultancy was responsible for the development of the OR model of all processes including concrete cutting works, reactor internals dismantling and waste processing operations. In addition training of project team members was undertaken by Taranto Consultancy to enable the project team to undertake further studies to evaluate design variations, and to understand the interdependencies between dismantling works and waste processing operations. The model has also been used to assess durations for each phase of the reactor dismantling work, and to underpin the project programme.
The work was undertaken largely in the UK, with several visits to the project team offices in Lyon, France for review meetings and training of project team members in the use of the model. Developed using Simul8 software, the model is by far the largest project simulation undertaken by VTNS, and its value has been recognised by the client, EDF’s CIDEN (Centre d’Ingenierie Deconstruction et Environnement), in evaluating alternative operating scenarios and designs.
Arthur Willis: VTNS Engineering Manager, Bugey APD Project Team