A flotation line for treating mineral ore particles suspended in slurry, comprising a scavenger part with a scavenger flotation cell for the separation of slurry into underflow and overflow; and a scavenger cleaner part comprising a scavenger cleaner flotation cell for the separation of slurry into overflow and underflow wherein - overflow from a scavenger flotation cell is arranged to flow into a regrinding step and then into the scavenger cleaner flotation part; - underflow from a last scavenger flotation cell of the flotation line and a last scavenger cleaner flotation cell of the flotation line is arranged to be removed from the flotation line as tailings; - at least 30 % of the flotation volume in the flotation line comprises a mechanical agitator comprising a system for introducing flotation gas into the flotation cell; - the flotation cells (120, 130) of the flotation line are connected in series and arranged in fluid communication so that a subsequent flotation cell is arranged to receive underflow from a previous flotation cell as slurry infeed; characterized in that - the scavenger part comprises a flotation cell with blast tubes for introducing slurry infeed into the flotation cell, and the flotation cell with the blast tubes is preceded by a scavenger flotation cell comprising a mechanical agitator, and/or - the scavenger cleaner part comprises a flotation cell with blast tubes for introducing slurry infeed into the flotation cell, and the flotation cell with the blast tubes is preceded by a scavenger cleaner flotation cell comprising a mechanical agitator, - and in that the flotation cell with blast tubes is configured to receive underflow from the preceding flotation cell as slurry infeed; and the blast tube is configured to restrict flow of slurry infeed from an outlet nozzle, and to maintain slurry infeed under pressure in the blast tube. - overflow from a scavenger flotation cell is arranged to flow into a regrinding step and then into the scavenger cleaner flotation part; - underflow from a last scavenger flotation cell of the flotation line and a last scavenger cleaner flotation cell of the flotation line is arranged to be removed from the flotation line as tailings; - at least 30 % of the flotation volume in the flotation line comprises a mechanical agitator comprising a system for introducing flotation gas into the flotation cell; - the flotation cells (120, 130) of the flotation line are connected in series and arranged in fluid communication so that a subsequent flotation cell is arranged to receive underflow from a previous flotation cell as slurry infeed; characterized in that - the scavenger part comprises a flotation cell with blast tubes for introducing slurry infeed into the flotation cell, and the flotation cell with the blast tubes is preceded by a scavenger flotation cell comprising a mechanical agitator, and/or - the scavenger cleaner part comprises a flotation cell with blast tubes for introducing slurry infeed into the flotation cell, and the flotation cell with the blast tubes is preceded by a scavenger cleaner flotation cell comprising a mechanical agitator, - and in that the flotation cell with blast tubes is configured to receive underflow from the preceding flotation cell as slurry infeed; and the blast tube is configured to restrict flow of slurry infeed from an outlet nozzle, and to maintain slurry infeed under pressure in the blast tube.