A settling basin of a wastewater treatment system, the settling basin comprises a collector chain for driving a plurality of flights through the settling basin, the collector chain including chain links comprising a plurality of side bars including a plurality of inner pairs of side bars and a plurality of outer pairs of side bars, and connecting pins configured to join the plurality of side bars, each connecting pin including a first end and a second end on an opposite end of the connecting pin from the first end, and flanged rollers disposed on the connecting pins between the first ends and second ends.

A conveyor system for transporting items from a receiving section to an outlet section includes a plurality of assemblies for carrying and transporting the items and a driving system. The driving system is configured to move the plurality of support assemblies from the receiving section to the outlet section. The driving system includes an endless chain of concatenated riving rods that are mutually hingedly connected, and an actuator for moving the endless chain of driving rods. Each support assembly is connected to a respective rod to be moved thereby in the transport direction. The actuator has a frame with two wheels that engage with the endless chain of concatenated rods. One of the wheels is a driving wheel driven by a motor. The actuator with the frame and wheels is mounted to the conveyor system such that it is movable substantially transversely to the transport direction.