Abstract: Device for treating waste water, especially rainwater by jointly carrying out degritting, degreasing and settling, which includes a degritter fitted with a grit trough, passed through by a descending then ascending flow of the water to be treated, a degreasing surface provided above a part of the degritter and the feed region of the settling tank, and a settling tank which includes a feed or presettling basin, a floor, a laminar settling region and an extraction trough, wherein the partition separating the degritter from the settling tank includes a flap valve making it possible, when it is open, to transfer the untreated water without perturbation towards the settling tank, and therefore allowing correct settling during this filling phase.

Abstract: A system for treating organic emulsions by separating by coalescence the disperse phase from the dispersion phase of the emulsion includes a single enclosed chamber having therein a lower destabilizing area, a central filtering and coalescence area, and an upper flotation and separation area. An emulsion to be treated is continuously introduced and passed upwardly through the destabilizing area, the filtering and coalescence area and the flotation and separation area. The flotation and separation area includes a center portion positioned vertically above the filtering and coalescence area and at least one lateral portion in flow communication with the center portion and extending laterally downwardly along a side of the filtering and coalescence area and the destabilizing area. The lateral portion of the flotation and separation area is laterally separated from the filtering and coalescence area and from the destabilizing area by a partition.

Abstract: A single enclosed chamber includes a lower destabilizing area, a central filtering and coalescence area containing coalescence material, and an upper flotation and separation area. Emulsion is introduced into the lower destabilizing area and is destabilized therein. The emulsion is then passed upwardly into the central filtering and coalescence area. The dispersed phase of the emulsion is attracted to the coalescence material in the form of droplets, and as the emulsion continues to pass upwardly therethrough the droplets grow in size. During passage of the emulsion through the filtering and coalescence material, matter in suspension is filtered from the emulsion. Within the flotation and separation area is located a separation device including a lower convergent portion and an upper divergent portion.