In cases where conversion cannot be made within the same set of hot cells, Brownfield conversion may only be possible if there are additional hot cells available in the facility or nearby. Research and development (R&D) could be carried out in hot cells in other facilities as well. Those hot cells could be used initially to carry out the R&D needed to support conversion and would eventually become the new LEU-based processing facility. This facility could be run in parallel with the HEU-based processing facility as long as needed to complete the conversion process. The two production facilities could be run in parallel, for example, to shake out the new process and train personnel. As will be discussed in Chapter 10, at least three of the existing large-scale Mo-99 producers (Mallinckrodt, Institut National des Radioéléments [IRE], and MDS Nordion) could likely convert using this approach.
Greenfield construction is advantageous primarily because it would not interfere with current Mo-99 production activities, and also because the new facilities can be custom-designed to meet current and projected future Mo-99 production needs. However, construction is likely to be substantially more expensive.
There are no recent examples of Greenfield construction for Mo-99 production. The Australian producer (Australian Nuclear Science and Technology Organisation [ANSTO]) is in the process of converting from an inefficient LEU-based process to a more efficient process using technology that was engineered and scaled up by the Argentine company Investigaciones Aplicadas Sociedad del Estado (INVAP) and CNEA from the CNEA-developed LEU-based process (see Chapter 3). ANSTO’s existing hot cell facility was substantially refurbished by INVAP (which also constructed the Open Pool Australian Lightwater [OPAL] reactor) as part of this conversion process. The new LEU-based processing facility designed and being constructed near Cairo, Egypt, by INVAP is an example of a Greenfield facility. However, this country is not an existing Mo-99 producer and plans to produce primarily for its own domestic needs and possibly to supply other countries in the region.
The time required for conversion will depend largely on which approach (Brownfield or Greenfield) is used. Both approaches share some common development steps that would require about the same amount of time, most notably for target design and fabrication and process development and testing (Chapter 7). Once this testing is completed, the setup and testing