A positionable gas nozzle assembly having a nozzle tube for injecting and directing pressurized air or other inert gas into a pellet slurry so as to increase the velocity of the slurry from a pelletizer to and through a dryer. The variably positionable nozzle tube can be inserted, retracted and/or intermediately positioned either manually or using an automated control system. The automated control system preferably includes a pneumatic cylinder movably engaged with a carriage that is fixedly coupled to the nozzle tube. The pneumatic cylinder contains a piston that is magnetically coupled with the carriage such that movement of the piston in response to the injection of pressurized air into the cylinder also moves the carriage and the nozzle tube to obtain the variable positions.