Abstract: A processes producing mechanical pulps utilizing refiners for improving the quality of screen rejects, and most particularly to a mechanical pulp mill integrated with a neutral-alkaline papermaking process producing mechanical printing paper grades is disclosed. The rejects are treated with hydrogen peroxide, an alkali and an organic stabilizing agent just prior to or during refining to provide improved optical and physical properties of the refined rejects and more efficiently utilize electrical energy to reach target fiber quality after bleaching for cost-effectively producing a wide array of coated and uncoated mechanical printing papers.