FLOTMAT 1/8 is a physico-chemical flotation system designed for the efficient treatment of wastewater from precast factories and concrete element sites. Developed by GECO, it uses wash water to separate aggregates from hydraulic binders and fine residues so that they can be recycled, the process water can be reintroduced into the process in compliance with concrete standards, and residual waste can be discharged into the network or the natural environment. Based on the counter-current principle, it separates 0.2–32 mm aggregates from grey water (mixture of water + fines << 0.2 mm). Aggregates, which are very dry thanks to a low-maintenance shaker, are 100% reusable; the grey water can be sent to a filter press treatment system, such as CWAS. Available capacities: 1, 2, 4 and 8 m³/h.

Concrete residues from mixers, skips, chutes or washing stations are dumped into a receiving hopper (often equipped with a washing lance and a trough or swing arm). These residues or wash water are transferred to the FLOTMAT washer, which facilitates the settling of aggregates. Aggregates larger than 2 mm are transferred by a screw to the rear of the washer and discharged through a vibrating chute while being rinsed to remove all cement residues. They can be recovered at the end of the vibrating chute for reintroduction. Microelements smaller than 2 mm are discharged by overflow with the water to an agitation tank. Concrete mixer trucks can be washed with grey water, otherwise it is reintroduced into the concrete process.