A distribution conveyor having a proximal and a distal ends, a first and a second sides and one or more adjustable side-discharging flow control valves between the proximal and distal ends, and a recirculation conveyor having a proximal end, proximal to the distal end of the distribution conveyor, and a distal end proximal a redeposit section of the distribution conveyor, wherein the valves can discharge a portion of a source stream of product from the distribution conveyor to a receiving structure underneath each valve, wherein the distal end of the recirculation conveyor is positioned to recirculate a tail stream from the distal end of the distribution conveyor to a redeposit section of the recirculating conveyor, and wherein the distal end of the recirculation conveyor is positioned to return the tail stream to the distribution conveyor laterally offset to a centerline of the distribution conveyor for preferential discharge in the valve(s).

An automated warehouse unit includes two rows of fixed conveyors conveying the storage target object in a first direction, a receiving-side transfer unit provided on one end portion side of the two rows and extending in a second direction, and a shipping-side transfer unit provided on the other end portion side of the two rows and extending in the second direction. Each transfer unit includes a moving device configured to reciprocally move a moving body in the second direction between a position facing one fixed conveyor in the fixed conveyors and a position facing the other fixed conveyor in the fixed conveyors, and a transportation conveyor supported by the moving body and configured to transfer the storage target object to the two rows in the first direction.