Speaker
Description
The IFMIF/EVEDA project is being carried out under the Broader Approach Agreement between the Government of Japan and EURATOM. As part of these activities, beam commissioning of the Linear IFMIF Prototype Accelerator (LIPAc) is underway in Rokkasho, Japan, with the objective of demonstrating the feasibility of continuous-wave (CW) acceleration of a high-intensity deuteron beam.
Since LIPAc generates a high-power deuteron beam of up to 1.125 MW, stable operation of its water-cooling systems is essential for ensuring accelerator reliability. However, the LIPAc team continues to experience water-flow clogging issues in both the primary and secondary cooling circuits. One contributing factor is the limited effectiveness of conventional filtration devices, such as strainers and cloth filters, in capturing particles either remaining from the fabrication of cooling-water piping or generated during operation through corrosion and erosion processes.
In general, stainless steel and copper are widely used in accelerator cooling-water systems. Without proper pickling and passivation treatments after stainless-steel pipe welding, the formation of iron-oxide corrosion products is nearly unavoidable. Likewise, copper-oxide particles can be generated unless advanced water-treatment measures, such as deaeration and pH control, are implemented. Furthermore, the risk of particle generation becomes greater when additional materials, such as brass and aluminum, are incorporated into cooling circuits together with stainless steel and copper, owing to the increased likelihood of galvanic corrosion.
This poster presents countermeasures implemented at LIPAc to mitigate water-flow clogging, including the installation of additional cloth filters and the optimization of strainer mesh sizes. Furthermore, potential improvements for future LIPAc operation are discussed, such as the introduction of bypass lines that would enable strainer and filter replacement without interrupting cooling-water circulation.