Patent ID: 8167133

Claim:
An injector of a flotation cell, the injector comprising a feed pipe for feeding a fiber suspension flow into the flotation cell, a mixing apparatus for mixing air into the fiber suspension flow and at least one air feed connection arranged before the mixing apparatus for feeding air into the injector, wherein: the injector further comprises a nozzle section which is arranged before the mixing apparatus and comprises an aperture plate provided with apertures and nozzles fixed to the aperture plate substantially at the apertures after the aperture plate, there being open spaces between the nozzles and the apertures in the aperture plate of the nozzle section being arranged to divide the fiber suspension flow to be fed into the feed pipe into partial flows, and the nozzles of the nozzle section being arranged to guide the partial flows into the mixing apparatus, and the aperture plate of the nozzle section being arranged before the air feed connection so that the air feed connection is arranged in the injector in the area surrounding the nozzles of the nozzle section so that the air to be fed from the air feed connection is arranged to flow into the spaces between the nozzles and further into the mixing apparatus with the partial flows of the fiber suspension flow entering from the nozzles; the mixing apparatus comprises pipe sections where the partial flows of the fiber suspension flow are guided from the nozzles and where the partial flows and the air carried by them are arranged to be mixed into each other; ends of the pipe sections of the mixing apparatus that are to be directed at the nozzles of the nozzle section are fixed to the nozzles of the nozzle section; and there is at least one opening on the side of the pipe sections of the mixing apparatus to enable air flow into the mixing apparatus.