Infrastructure > Experimental Devices > MELILOO


MELILOO, which is an abbreviation of “Metal Liquid Loop”, is an experimental device for the examination of the circulation of Pb-17Li liquid eutectic; MELILOO is meant for the study of Pb-7Li eutectic application as the coolant in fusion reactor ITER, TBM section in particular.



The MELILOO loop serves for experimental verification of purification methods for Pb-17Li liquid eutectic, i.e. liquid metal consisting of 83 % lead (Pb) and 17 % lithium (Li). The purification is aimed at corrosion products. The Pb-17Li eutectic is envisioned for use in TBM for the purpose of tritium transport from the breeding section to the Tritium Extraction Unit (TEU), a special device which removes tritium gas from liquid eutectic for further processing.

Nominal Parameters

Temperature in hot part up to 550 °C
Temperature in cold trap 300 °C
Gas pressure max. 2 bar
Eutecticum mass 96 kg

Experimental Possibilities

The dosed impurities, which simulated exposure to corrosion products, consisted of Fe, Cr, Mn and Ni. Their removal efficiency went from 80 % with Mn and 70 % with Ni to 30 % with Fe and almost 0 % with Cr. Such results were used for further development of the cold trap. Dosing of impurities is also connected with their analysis from obtained samples – in the framework of the project aimed at the development of metal liquid coolant technologies, the selection of the most proper chemical analytical method was made: impurities are present in trace amounts, often on the edge of the apparatus sensitivity.

The most suitable method was identified in Inductively Coupled Plasma with Optical Emission Spectrometry technique (ICP-OES). The MELILOO loop is also used for determination of a pump performance chart for the main circulation pump with Pb-17Li eutectic. The loop is capable of measuring pump performance charts in a special piping setting. It is important to mention that MELILOO’s measuring capacity differs from other similar systems: the common systems are measuring pump performance charts with water and the results are later recalculated to Pb-17Li eutectic, but in the case of the MELILOO the Pb-17Li is directly used instead of water. Such an approach provides more accurate results and fits more to ITER requirements.



1 circulation pump;
2 mechanical samples;
3 cooler;
4 cold trap;
5 sampling