... area, large pore volume, the ceramic sand filters is of great amount of pollutant entrapment, up to 9-10 kg/m3, about ... 1.2 or 1.5 times that quartz sand filter of 7.8-9 kg/m3;4 ... 3. Technical Indexes of Ceramic Sand Filters ItemIndex Remark Particle size,mm0.5-3.0- Bulk density, g/ml1.1-1.5-Free volume,%40 ... solution for 14 days 4. Product Size(mm):Φ0.5-1,Φ1-2,Φ2-3,Φ5-6,Φ6-8,Φ8-10,Φ10 ...