with GOST R 51641-2000

Summary

Possible errors while determining the properties of filtering granular materials are laid down in GOST R 51641-2000 «Granular filtering materials. General specifications» because of the inaccuracies in the test methods. Based on the experience of NII VODGEO in performing tests of various filtering materials, suggestions on improving and adjusting these methods are presented that provide for obtaining reliable and reproducible results for the estimation of the physical and chemical properties of materials. To obtain actual reproducible results according to the main methods defined in GOST R 51641-2000, correcting the processes of sample preparation, determination of chemical resistance indicators and mechanical strength of the filter material is needed in accordance with the proposed recommendations. These proposals, based on the work experience in testing various filter materials (sand, zeolite, activated carbon, etc.), provide for obtaining reliable reproducible results that do not contradict the methods of GOST R 51641-2000.

Key words

physical integrity , filtering granular material , testing method , GOST R 51641-2000 , estimation of physical and chemical properties , chemical resistance

Comparative analysis of the physicomechanical properties
of natural materials used as filter media

Summary

The results of the study of physicomechanical properties of filtering materials – crushed expanded clay with a bulk density of 525 and 555 kg/m³ and Diamix AQUA with a bulk density of 670 kg/m³ are presented. Easy upheaving clays of a certain chemical and mineral composition serve as raw materials for expanded clay production, for Diamix AQUA production raw material based on natural diatomite that includes exoskeletons of diatoms is used. Oxide concentration in Diamix AQUA is: SiO₂ more than 83%, Al₂O₃ less than 6% and Fe₂O₃ less than 3.5%. Diamix AQUA filtering material has a National Registration Certificate. The research results showed that the new filtering material based on Diamix AQUA can be used as media for newly constructed filtration facilities. To regenerate the filter media, an increased backwashing rate is needed, which requires checking the throughput of the filter drainage and distribution system to pass through the increased water flow rate.

Ключевые слова

water treatment , filtering material , bulk density , apparent specific gravity , physical integrity , backwash rate