Facts & Figures Book - KPI-JCI

In general, the finer the sand, the deeper the weight willpenetrate. The wetting agents that dissolve the clay makea seemingly coarse material much finer because the claysare now a separate, very fine product. This extra finematerial acts as a lubricant and the weight will descenddeeper in the sample. Because of this, it is possible thata sample with an acceptable FM is rejected for failure topass the SE test.Washin g/Classifyin gCOARSE MATERIAL WASHINGIn order to produce aggregate at the most economicalcost, it is important to remove, as soon as possible,from the flow of material, any size fraction that can beconsidered ready for use. The basic process consists ofcrushing oversize material, scrubbing or washing coatingsor entrapped materials, sorting and dewatering.Beneficiation of some coarse aggregate fractions maybe necessary. When scrubbing or washing of coarsematerial is required, it is generally a consideration of thematerial size, the type of dirt, clay or foreign material tobe scrubbed and the tons-per-hour rate needed that willdetermine the coarse material washing equipment to use.100