Abstract: A pulper to convert bulky, solid wastes from food service establishments into a uniform, moist pulp. The material is pulverized in a first section and transferred as a slurry to a second section where the slurry is dewatered by an auger. To prevent clogging of the auger, a portion of the liquor extracted from the pulp is introduced as a jet stream into the upstream end of the auger to create turbulence. Additionally, a reverse flow of water through a drain chamber in excess of the amount of water required for make-up in the system is employed to prevent clogging of the screen covering the drain.