Developed by the scientists from Armenia, super-thin basalt fiber-based filter systems with cleaning efficiency about 99% have become a major step towards solving radiation safety problems at nuclear-powered industrial enterprises.
The full cycle of fundamental and applied research was carried out under the guidance of Professor Vachagan Harutyunyan, who heads the Department of Applied Physical Research at A.I. Alikhanian National scientific laboratory (Yerevan).
The issue of neutralization and purification of gas emissions and aerosols is considered a major task in different industries. For this purpose, various sorbents that fulfil high criteria are used.
The main criteria are radiation, thermal and chemical resistance, durability, recyclability required for repeated application etc. Basalt fibers meet almost all these requirements.
The scientists started with physical and chemical studies to find a suitable deposit in Armenia with raw materials that meet the required chemical composition. These raw materials were used to manufacture super-thin basalt fiber (BSTF), characterized by high strength, radiation, chemical and thermal resistance.
Fibers sized 1-3 microns in diameter were further modified by a chemical method (leaching) to enhance filter material characteristics.
There were several pilot lots modified differently. Super-thin basalt fiber-based filter materials were tested at the experimental facility installed at the Armenian NPP. Then, they were used as a basis to manufacture and test industrial filtration units that are similar to those installed in ventilation systems of nuclear power plants.
The system monitored with participation of colleagues from Canada and Armenian NPP proved that the efficiency meets the IAEA standards. Moreover, BSTF-based filtration system demonstrated efficiency of 98.4 – 99.6%, which is comparable to efficiency of expensive and difficult-to-replace Petryanov filters.
The scientists have also developed a production and technological cycle for manufacturing these filtering systems, and what is more, they developed a technology of used filters regeneration after their decommissioning.