Overview of R&D at TLK for process and analytical issues on tritium management in breeder blankets of ITER and DEMO

Safe, reliable, and efficient tritium management in the breeder blanket will have to face unprecedented technological challenges. Beside the efficiency for tritium recovery from the breeder blanket (Tritium Extraction (TES) and Coolant Purification Systems (CPS)), the accuracy for tritium tracking between the inner and the outer fuel cycle must also be demonstrated. This paper focuses on the recent R&D carried out at the Tritium Laboratory Karlsruhe to tackle these issues. For ITER, the recently consolidated TES and CPS designs comprise adsorption columns and getter beds operated in semi-continuous mode. Different approaches for the tritium accountancy stage (TAS) have been evaluated. Balancing static (batch-wise gas collection at the TBM outlets and the tritium plant) or dynamic (in/on-line) approaches with respect to the expected analytical performances and integration issues, the first conceptual design of the TAS for EU TBMs is presented. For DEMO, the overall strategy for tritium recovery and tracking has been revisited. The necessity for on-line real-time tritium accountancy and improved process efficiency suggest the use of continuous processes such as permeator and catalytic membrane reactor. The main benefits combining the PERMCAT process with advanced membranes is discussed with respect to process improvements and facilitated accountancy using spectroscopic methods.     

Physico-Chemical Characterizations of Poly(vinylidene fluoride)/Cu3(BTC)2 Composite Membranes Prepared by In Situ Crystal Growth

In this work, we present a simple and fast method for elaborating hybrid membranes by growing metal–organic framework crystals inside a polymer solution. The solution thus obtained was casted then annealed at 90°C for 5 h. This method was tested with poly(vinylidene fluoride) (PVDF) as a piezoelectric polymer and the Cu₃(BTC)₂, BTC = 1,3,5-benzene tricarboxylate, as a filler. The characterization of the obtained membranes by attenuated total reflectance Fourier transform infrared spectroscopy and X-ray diffraction showed the presence of the characteristic signatures of Cu₃(BTC)₂ and the β-phase of PVDF. Moreover, scanning electron microscopy images reveal that the Cu₃(BTC)₂ crystallites have grown along the PVDF membranes. The effect of the filler on both thermal and mechanical properties of the membranes was also studied. POLYM. ENG. SCI., 60:464–473, 2020. © 2019 Society of Plastics Engineers     

Effect of height on the corrosion of steel and galvanized steel in nontropical coastal marine environments

In this study, the behavior of carbon steel and galvanized steel in nontropical coastal marine environments was evaluated. Evaluation was carried out with specimens with dimensions of 10 cm × 10 cm × 0.3 cm. These specimens were exposed to four testing stations (Iquique, Mejillones, Los Vilos, and San Vicente), where racks were installed both at ground level (ground), as well as in the upper zone of electrical transmission towers (tower). In each station, 24 specimens of A36 carbon steel and galvanized steel were placed (12 each). The corrosivity of the environment was measured using the ISO 9223, 9225, and 9226 standards. The specimens were evaluated on-site, monthly, through visual inspection and photographic record. Once withdrawn, the corrosion rate was determined and the corrosion products were analyzed through Raman and Fourier-transform infrared. The results show that, in all cases, the corrosion rate is greater in the tower than on the ground. However, even though the Los Vilos station is located farther from the sea (3,500 vs. ≈500 m), the corrosion rate of steel in the tower is the highest. This is caused by the generation of HCl from the transformation of lepidocrocite into goethite, in the presence of low chloride content, which acidifies the steel/corrosion product interface. In the case of galvanized steel, the corrosion rate is a function of the chloride content in the atmosphere, obtaining an excellent correlation between both parameters.