A continuous product-processing apparatus having a conveyor capable of repositioning product and cleaning itself of debris and a method for its operation. The apparatus includes a conveyor that transports products atop a conveyor belt along a carryway to a processing chamber. Upper and lower diverting rollers guide the belt along an S-shaped product-repositioning path segment of the carryway. The diverting rollers are rotated at a speed normally greater than the speed of the conveyor belt to cause the belt to slip on the roller's periphery, which effects a scraping action against the conveying side of the belt to dislodge debris from the belt and the rollers. One-way ratcheting drives or belt restricters positioned on the product-positioning path segment to limit belt excursion are used to prevent the belt from building up along the carryway and tightening in the lower return.