| 摘要 |
PROBLEM TO BE SOLVED: To enlarge particles of dregs and improve the filtration efficiency by using sodium alginate together with silica gel. SOLUTION: Silica gel and sodium alginate are added to an impurity- containing liquid material to remove produced dregs. Sodium alginate to be used is not specifically limited and an aqueous solution in 1 wt.% concentration has the viscosity (measured at 20 deg.C) preferably not less than 10 cp, more preferably 30-150 cp, most preferably not less than 70 cp, and particularly preferably 70-800 cp. It is preferable to use sodium alginate having the viscosity within above viscosity ranges since flocs of the dregs become firm and particles are hardly broken and the particles of the dregs easily become large. Silica gel to be used is not specifically limited and common silica gel can be used. Generally, silica sol containing 15-45 wt.% of silica is preferable. |
