The total feed flow to the first cell is pumped through the Multi – Injectors. Within the flotation tank, the stock is pumped strictly in forward direction from cell to cell. To provide the required air, the accept of each cell is pumped through the Injectors of the following cell, thus providing aeration for 100% of the stock. The Multi – Injectors are sucking in the air in one step injector and can achieve An aeration ration up to 0.8 ( air volume is 80% of the volume of the stock, which is flowing through the injectors). The air is taken directly from the inside of the flotation tank at ambient pressure, no compressed air is required. The overflow (foam) from the 1st flotation stage is collected in two foam – collecting pans, which are located along both sides of the flotation tank and flowing into the foam tank. There, it is destroyed mechanically by means of the defoam unit located at the top of the foam tank and fed to the secondary cells. The accept stock from the secondary cells is fed back to the first primary cell. Foam from secondary cells is piped to the sludge tank and pumped to the sludge dewatering unit.