Authors & Affiliations
Martynov P.N., Askhadullin R.Sh., Papovyants A.K., Voronin I.A.,
Yagodkin I.V., Melnikov V.P.
A.I. Leypunsky Institute for Physics and Power, Obninsk, Russia
Abstract
Lead and lead-bismuth eutectic alloy as coolants of promising nuclear power plants present the low concentration fine suspensions containing different suspended solid particles (oxides of lead, bismuth, iron, chromium, manganese, oil pyrolysis products, etc.). Properties and behavior of these impurities influence on the coolant heat exchange and hydrodynamics in different parts of the circuit resulting in even critical situations connected with slag blockade and suspension separation on heat exchanging surface.
To prevent these situations the coolant and circuit complete purification is proposed by the application of filtration to remove “non-regenerated” impurities in addition to hydrogen regeneration (removal of “regenerated” impurities).
It has been shown that suspended particles of micron and submicron dimensions contribute decisively to slag-making. Volume type filtering materials are the most suitable for capturing of these impurities.
In connection with this a wide range of filtering materials was analyzed and tested – fiberglass and carbon fiber, basalt fabric, needled fabric made of metal fiber, Al2O3 aluminum oxide grains, Ti, etc. Multi-layer silica texture fiberglass MKTT-2.2A (4-5 mm thickness, 6 mm fiber diameter) and needled fabric made of metal fiber (2-6 mm thickness, 40 µm fiber diameter) are appeared to have the best set of parameters including adhesive behavior, impurity removal efficiency, hydraulic resistance, thermal stability, chemical resistance. Filter models for promising nuclear power plants have been developed on the basis of filtering materials chosen.
Key words
filter, cleaning coolant, lead-bismuth, polonium, heavy liquid metal coolant
UDC 621.039.58
Problems of Atomic Science and Technology. Series: Nuclear Constants, issue 2:8, 2015