Removal of silicon compounds from underground water by filtration through a modified media

Summary

A brief analysis of water desiliconization technologies is given. The results of experimental studies on the removal of silicic acid compounds from water by filtration through a modified media are presented. It is shown that the use of a filtering media made of activated alumina modified with 0.5% sodium aluminate solution acquires a sorption capacity twice as high as the media regenerated with alkali in relation to orthosilicates, and provides for 95–97% water desiliconization while reducing in-parallel the water hardness. The sorption capacity of the modified activated alumina in relation to silicon is 16kg in terms of SiO₂ per 1 m³ of sorbent, which is twice as much in silicon holding capacity compared with the technology of desiliconization by regeneration of activated alumina with caustic soda. The working exchange capacity of the modified activated alumina in terms of the absorbed total hardness is 300–350 g-eq/m³, which is comparable to sulfonated carbon and KU-1 cation exchanger. A non-waste technology of desiliconization of groundwater with re-using the modifying chemical agent generated in the form of dehydrated crystalline aluminosilicate as a commercial raw material for the production of ceramic products has been developed.

Ключевые слова

potable water , filtration , sodium aluminate , desiliconization , activated aluminum oxide , alumosilicate sludge , media modification