FLOCKNINGSMEDEL OCH FOERFARANDE FOER FRAMSTAELLNING AV DETTA

摘要

A flocculant for water treatment, containing a highly polymerized silicic acid solution having a high concentration of SiO2 and an extremely low concentration of alkali metal material, and a process for producing such a flocculant. The silica solution is produced by treating an aqueous solution of an alkali metal silicate, such as water glass, for the removal of alkali metal and by letting the solution re-liquidize after having once been a gel. The flocculant can further comprise a water- soluble metallic salt, such as ferric chloride or ferric nitrate.