A screw conveyor or auger conveyor is a mechanism that uses a rotating helical screw blade, called a “flighting”, usually within a tube, to move liquid or granular materials. They are used in many bulk-handling industries. Screw conveyors in modern industry are often used horizontally or at a slight incline as an efficient way to move semi-solid materials, including food waste, wood chips, aggregates, cereal grains, animal feed, boiler ash, meat, and bone meal, municipal solid waste, and many others.