The problems of protection and heat insulation of steel tanks which are used in hydrogen power engineering

The trends in the development of hydrogen power engineering as an alternative environmentally friendly source of energy are given. The problems of hydrogen storage in steel spherical tanks, mainly related to the thermal insulation of the tank, are considered. The structure of steel spherical tanks for storing liquid hydrogen at low temperatures, which, as a rule, is 21 K, the hydrogen condensation temperature, is considered. The characteristics of AISI 316L austenitic stainless steel, developed on the basis of the AISI 304 steel grade, improved by 2.5 % molybdenum addition, which increases its corrosion resistance and allows the use of AISI 316L steel in aggressive environments, and therefore found the widest application in the design of spherical hydrogen tanks, are presented. The chemical composition of AISI 316L austenitic stainless steel is displayed. A number of heat-insulating materials for hydrogen storage in steel spherical tanks are considered. The characteristics of the expanded pearlite currently used for this purpose, which has a number of disadvantages, such as caking of the material, high costs in its production, loss of thermal insulation properties after a certain cycle of thawing -freezing, are shown. The parameters of alternative heat-insulating materials, such as aerogels, polystyrene foam, foam glass, are examined. It has been established that aerogels, despite all their advantages, are not stable in an oxygen environment and are a very expensive as material; expanded polystyrene, being an organic substance, is a subject to flammability, and therefore is not suitable for use in hydrogen energy. Foam glass was identified as the most promising heat-insulating material, which has a number of advantages over other materials. Compositions of charge for obtaining foam glass have been developed, and a series of samples of foam material has been synthesized. The optimal composition of foam glass was chosen, which is most suitable for storing hydrogen in steel spherical tanks.