Its mission is to eliminate the solids carried by the water, in order to avoid clogging and mechanical problems in the installations.

This equipment requires little maintenance and operates continuously, without the need for electricity.

In urban waters, they can replace primary decanters in many cases, providing the elimination of coarse sands and up to 30% percentages of grease and effluent leftovers. Spans of 0.50 to 0.15 millimetres are used.