... volume AL2O3%: 18-25% 1. Product Description Ceramic sand filters are doped with rare earth element and ... Compared with traditional sands and coal filter material, ceramic sand filters have great advantages as follows:1. ... or coal filters itself. 2. Chemical Composition of Ceramic Sand Filters Composition Content % Al2O3 18-25% SiO2 ... -3,Φ5-6,Φ6-8,Φ8-10,Φ10-12,Φ13-16,Φ16-20,Φ20-30. Ceramic Sand Filters