The invention relates to an improved design of the bottom of a continuous digester reducing the torque load on conventional bottom scrapers with scraper arms arranged at an angle α in relation to the horizontal plane in the range between 5°-30°. A simple digester shell extension VE is installed below the lowermost wash screen WS, ending at a small distance D above the end of the outer end of the scraper arm. The shell extension prevents the descending pulp column from expanding below the wash screen and enables easier shaving action from the scraper, using a dilution and expansion volume established at the outer ends of the scraper arms.