Desanders are used to separate sand which is mixed with drilling muds. During drilling process mud is being poured as excavation is getting deeper, this mud also mixes with soil, thus being contaminated with sand and silt, in such a way, that when excavation is finished, it is necessary to recyle mud in order to separate sand from mud and get a clean mud that will be used in next excavations. Each country establishes its own regulations on maximum allowed sand content in drilling mud before concreting operation is carried out, in order to prevent concrete contamination with sand and soil, and Desanders are used for this purpose.