Molten salt test loops

Several experimental loops have been constructed at SINAP, including the HTS molten salt test loop (Fig. 14.18), the FLiNaK molten high-temperature salt test... 

Figure 14.18 Schematic diagram of the high-temperature salt molten salt test loop. Cover-gas... 

Han, L., Chen, Y., Zhou, D., 2013. Design of the distributed control system for HTS molten salt test loop. Nuclear Techniques 36. 

Require testing and qualification of materials to >1000 C in molten salt flow loops... 

After the preliminary selection of 300 series stainless steel, these alloys were subjected to further tests to study the effect of stress in the presence of chloride, oxygen, and water vapor, the effect of sensitization, and the rate at which the alloying constituents are leached and transported under the influence of a temperature gradient. A molten salt loop has been in operation for nearly a year as a part of these tests. The... 

An electrochemical hydrogen meter based on ternary molten salts with CaCl2 and CaHCl as two components of the electrolyte was constmcted and tested in a bench-top sodium loop. Further tests regarding the long term performance of the meter are in progress. 

These billion dollar programmes developed the technology base for use of liquid salts in nuclear systems. Two experimental reactors were built and successfully operated. The aircraft reactor experiment (ARE) was the first MSR. It was a 2.5 MW(th) reactor that was operated in 1954 at a peak temperature of 860°C and used a sodium-zirconium fluoride salt. This was followed in 1965 by the molten salt breeder reactor (MSBR) Experiment, an 8 MW(th) reactor that used a lithium-beryllium fluoride salt and demonstrated most of the key technologies for a power reactor. In addition, test loops with liquid salts were operated for hundreds of thousands of hours, materials of construction were code qualified to 750°C, and a detailed conceptual design of a 1000 MW(e) MSBR was developed. Over 1000 technical reports were produced. 

ORNL LORD Hastelloy-N Molten-Salt Corrosion Test Loop Will Be Operational March 2003... 

Figure 14.19 Schematic diagram of FLiNaK molten salt high-temperature testing loop.

Zou, X., Dai, Z., Tang, Z., 2013. Numerical simulation of induction heating in FLiNaK molten salt high temperature testing loop. Nuclear Techniques 36. 

Test loop Structural material Molten salt (mol%) Circulation mode (°C) (°C) Exposure (h) Specimen temp. (°C) Corr. Rate (pfft/year)... 

In the thermal convection loop operated with molten Li,Be,Th,U/F salt system the HN80MTY alloy specimens have shown the maximum corrosion rate at 6 pm/year (see Table 5.5), as for the HN80MT alloy it was two times lower [16,58]. The corrosion was accompanied by selective leaching of chromium into the molten salt, which is evidenced by the 10-fold increase in its concentration with reference to the initial one for 500 h of exposure. Similar oxidizing conditions characterized by the same content of Fe and Ni impurities in the salt took place in testing a standard Hastelloy N alloy on... 

In the tests run thus far, no positive indication has been found of carburization of the nickel-alloy containers exposed to molten salts and graphite at the temperatures at present contemplated for power reactors (< 1300°F). The carburization effect. seems to be quite temperature sensi-ti e, however, since tests at 1500°F showed carburization of Hastelloy B to a depth of 0.003 in. in 500 hr of expo.sure to NaF-ZrF4-UF4 containing graphite. A test of Inconel and graphite in a thcrmal-convection loop in which the maximum bulk temperature of the fluoride salt was 1500°F gave a maximum carburization depth of 0.05 in. in 500 hr. In this ease, however, the temperature of the metal-salt interface where the carburization occurred was considerably higher than 1500°F, probably about 1650°F. 

In corrosion studies [59—61] the central focus was placed on the compatibihty of Ni-based alloys with molten Li,Na,Be/F salt system as applied to primary circuit of MOSART design fueled with different compositions of actinide trilluorides from LWR spent fuel without U-Th support. These studies (see Table 5.5) included (1) compatibility test between Ni-Mo alloys and molten 15 LiF-58 NaF-27 BeF2 (mol%) salt in natural convection loop with measurement of redox potential (2) study on PuFs addition effect in molten 15 LiF-58 NaF-27 BeF2 (mol%) salt on compatibility with Ni-Mo alloys and (3) Te corrosion study for molten 15 LiF-58 NaF-27 BeF2 (mol%) salt and Ni-Mo alloys in stressed and unloaded conditions with measurement of the redox potential. Three Hastelloy N type modified alloys, particularly, HN80M-VI with 1.5% of Nb, HN80MTY with 1% of Al, and MONICR [59] with about 2% of Fe, were chosen for our study in corrosion facilities (see Tables 5.3 and 5.6). 

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